CA1138347A - Electric vehicle propulsion system powered by continuously-running heat engine - Google Patents

Abstract

A B S T R A C T

A constant-speed continuously-running low-powered diesel engine or turbine drives a two-phase alternator, the output from which, for direct drive, flows to the stator pole piece windings of four independently-rotating stepping motors operating syn-chronously with the alternator. Each stepping motor is connected to a traction wheel of a motor vehicle, thereby propelling at limited maximum speed sufficiently to overcome normal wind resis-tance over a level road. In starting, during acceleration, and for propulsion at lower speeds, direct current from a storage battery is caused to pulsate and is added to the current from the alternator to the stepping motors. A control circuit selec-tively controls the frequency of a variable frequency generator electrically connected to the pulse-responsive electrical power system to vary the frequency of the current supplied to the step-ping motors and thus vary the vehicle speed. During idling, the alternating current from the alternator is rectified and recharges the battery. During braking, the consequent driving of the step-ping motors causes them to generate alternating current which is rectified and returned to the battery. By varying the frequencies of the current delivered to the right side motors as compared with those delivered to the left side motors and vice versa, in response to the turning of the steering wheel in rounding a curve in the road, a differential action is obtained.
In a modification, combustion of fragmented slow-burning solid fuel, such as wood fragments, in the combustion chamber of a portable combustion receptacle or pressure vessel mounted on the rear of the vehicle, is initiated by igniting in the combus-tion chamber combustible starting fluid gas, such as propane gas from an external source and ignited by a spark plug. Air is sup-plied by an air compressor driven by a prime mover such as a turbine or electric motor. As soon as combustion of the solid fuel has become self-sustaining, the supplying of this starting gas is terminated. Meanwhile, the pressurized gas emitted from the burning solid fuel in the combustion receptacle is discharged into the power turbine by way of a throttle valve. The output shaft of the turbine drives a speed-reducing transmission which in turn drives the alternator.

Description

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A constant-speed conti.nuously-running low~powered diesel engine or turbine drives a two*~hase alternator, the output from which, Eor direct drive, flows to the stator pole piece windings of four independently-rotating stepping motors operating syn-chronously with the alternator. Each stepping rnotor is connected to a traction wheel o~ a motor vehicle, thereby propelle~ at a limited maximum speed sufficiently to overcome normal wind resis-tance over a level road. In starting, during acceleration, and for propulsion at lower speeds, direct current from a storage lo battery is caused to pulsate and is added to the current ~rom the alternator to the stepping motors. ~ control circuit selec-tively controls the fre~uency of a variable frequency generator electrically connected to the pulse-responsive electrical power system to vary the frequency of the current supplied to the step-ping motors and thus vary the vehicle speed. During idling, the alternating current from the alternator is rectified and recharges the battery. During braking, the conse~uent driving of the step-ping motors causes them to generate a]ternating current which is rectified and returned to the bat~eryO ~y varying the frequencies of the current delivered to the right side motors as compared with those delivered to the left side motors and vice versa, in response to the tur~ing of the steering wheel in rounding a curve in the road, a differential action is obtained.
In a modification, combustion of fragmented slow-burning solid fuel, such as wood ~ragmen-ts, in the combustion cham~er of a portable combustion receptacle or pressure vessel mounted on --lt`

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the rear of the vehicle, is initiated by igniting in the combus-tion chamber combustible starting :Eluid gas, such as propane gas from an external source and .ignited by a spark plug. Air is sup-plied by an air compressor driven by a prime mover such as a tur-bine or electric motor. As soon as combustion of the solid fuel has become self-susta~ning, the supplying of this starting gas is terminated. Meanwhile, the pressurized gas emitted from the bur-ning solid fuel in the combustion receptacle is discharged into the power turbine by way of a throttle valve. The output shaft of ].0 the turbine drives a speed-reducing transmission which in turn drives the alternator.

BACKGROU~ OF THE I~V~IO~

Research on fuel consumption oE conventional motor vehicles driven by internal combustion engines has shown that approximately one-half of the fuel consumed by such an engine is expended and atmospheric pollution increased during starting and idling, es-pecially during urban driving with frequent halts ~or stoplights and traffic. Fuel has also been wasted in such vehicles through the differential mechanism and through momentum losses by braking, not only in traffic halts but also in downhill running. In view of the increasing scarcity of li~uid Euels, there is a likelihood of their being in the near fu~ure obtainable, if at all, only at prohibitively high costs. The modified portable electri.c power plant of my present;~imY~ntion drives the alternator o~ my prin~
cipal system :Erom a gas turbine receiv~img power gas from a por-table combustion receptacle or pressure vessel in the combustion chamber o~ which suitable subdivided slow-burning solid fuel, such as wood, is burned to produce such hot and expanded power gas.

SUMM~RY OF TEIE INVENTIOM

The invention principally rssides in the provision of independent stepping motors individually driving the vehicle's traction wheels, as these motors are operating synchronously with a two-phase engine-driven alternator while receivirl~ al-ternatiny current from that alternator driven by a continuously-running constant-speed internal combustion engine of considerably less power and fuel consumption than would be required ~or all-around propulsion o the vehicle by an internal combustion en-gine alone but increased, when neededI; by direct current supplied from a st.orage battery and caused to pulsate at the proper frequency. ~he invention also resides in the provision of means which converts inerti.al energy otherwise lost in braking or free-wheeling into alternating current electricity which is rec-tified and returned to recharge the storage battery. It ~urther resides in electrical means responsive to the ~Gurning of the vehicle's steering wheel for reducing the frequencies o~ the current supplied to the stepping motors on the inside of a road curve from those on the outside thereof, thereby providing an electxical differential.
The modification of the invention resides primarily in the provision of -tha portable combustion receptacle or pressure vessel wherein combustible s]ow-burning so:Lid fuel particles, fragments or bloc]cs, preferably of wood, are ignitsd by being initially supplied with a combustible start;ing ~luid, such as fuel gas ignited by a spark plug or glow p:Lug and subse~uently terminated when the combus-tion of the solid fuel particles becomes self-sustaining. The modification further resides in the provision of the turbine-powered alternatDr driven by the pressurized hot output power gas from the combustion chamber of the combustion receptacle, the electricity thus genexated being supplied to the place of util.izat.ion, such as the h~rein dis-closed electric vehicle propulsion system. The modification still further resides in the provision of duplex combustion recep-tacles utili~ed alternately for enabling continuous operation to be effected by havi.ng one such solid-fuel-filled combustion receptacle always held in reserve for use when the other com-bustion receptacl.e has exhausted its fuel supply.

In the drawings, Figure 1 is a block diagram of the stepping-motor-driven vehicle propulsion system supplied with alternating current from a continually-running constant-speed engine-driven alternator aided by pulsating direct current from a storage battery;
Figure 2 is a diagrammatic top plan view of the chassis of the vehicle of Figure l;
Figure 3 is a diagrammatic central vertical section along the line 3--3 through the vehicle of Figure 2;

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Figure 4 is a vertical cross-section taken along the line 4- 4 in Figu.re 2;
Figure 5 is a circuit diagram of the two-phase elec trical system involved in ~he propulsion of t:~e st~pping motor of Figure l;
Figure 6 is a logic circuit diagram employed in direct drlve or free-wheeling of the vehicle of this invention;
Figure 7 is a clrcuit diagram of the variable frequency differential action obtained in rounding a curve in the present vehlcle;
E'igure 8 ls a logic circuit dia~ram for the two-phase alternatlng curren~ emitted from the alternator and rectified by silicon-controlled recti.fiers;
Figure 9 shows the regenerative braking circuitry for recovering and rectifying alternating current from the vehicle wheel stepping mot.ors acting as wheel~driven generators;
Figure 10 on the same sheet as Figure 1 is a block dlagram constituting Fiyure 9 of Fengler Canadian ~atent No.
873,514 o~ June 15, 1971 but receiviny power current from a direct current power source in the present vehicle propulsion system, and with its output to additional stator windings designated by different reference numerals;
Figure ll on the same sheet as Figure 2 is a cross-section like Figure 7 of my said prior patent but showing said addltional stator windings of my present stepping motors;
Figure 12 is a diagrammatic side eleva-tion, partly in central vertical section, of a portable solid Euel electric power plant for electrical powered vehi.cles according -to a modification of the invention; and Figure 13 is a diagra~matic top plan view of the power plant shown in Figure 12.

General Arranqement -The block diagram shown in Figure 1 illustrates the general arrangement of the assembled components of the stepping mo-tor vehicle propulsion system, generally desiynated 10, ac~
cording to the invention, the details of which are shown in detailed circuits of FigureS 5 to 9 inclusive. The vehicle propulsion system 10 (Figure 1), assumed to be a foux-wheel driving system with independent motor dri~ing to the individual vehicle wheels, originates with a power source 12 consisting of a continuously-runniny c~nstant-speed internal combustion engine such as a Diesel engine or a gas turbine having a drive coupling 14 connecting it to a two-phase 400-cyc].e approxi.mately 22 kilowatt alternator 16. From the alterna-tor 16 the main al-ternating current output connection 18 proceeds through a junc-tion 2Q and an alternating current output connection 22 with branches 24, 26, 28 and 30 -to the right-hand front driving step ping motor 32, the left-hand front driving stepping motor 34, the right-hand rear driving stepping motor 36 and the left-hand rear driving stepping motor 38 respectively. The driving step-ping motors 32, ~4, 36 and 38 are separately designatad becausq the motors on opposite sides o~ the vehicle receive a].ternating ~, current of di:Eferent frequencies at di~ferent times to provide an electrical differential action for the ~ehicle when rounding curves or turning corners in the roadway. In this respect, as described more fully below, the different re~olutions imparted to the right-hand motors 32 and 36 from those imparted to the left-hand motors 34 and 38 provide a corresponding action to the mechanical differential mechanism of a conventional automobile.
It will be seen later that the output connection 22 and branches 24, 26, 28 and 30 carry alternating current from the a:Lternator 16 in direct drive but also carry pulsating direct current regulated by -two pulsating current frequency generators 76 and 86 described below.
From the junction 20 a two-phase full-wave rectlfier 42 receives alternating current through the alternating current con-nection 44 and transmits it through the two-phase full-wave rec-tifier 42 and connection 47 to a storage battery 48, to charge the latter under the regulation of a battery-charged monitor 50 connected thereto through the connection 52 and connection 54.
sraking is accomplished primarily by the motors 32, 34, 36 and 38 acting as alternators through their mechanic~ connections to the vehicle ground wheels and consequently alternating current through the current connections 56, 58, 60, 62 is transmitted to the accelerating and decelerating current controller 64 from ~hich it proceeds through the alternating current connections 66, rec-tifier 68 and direct current connect1on 70 to the storage battery 48. A bypass connection 46 diractly connects the storage battery 48 to the accelerating and decelerating current controller 64 ~ ~L 3 ~

around the rectifier 6~ during acceleration of the vehicle to supply additional pulsating direct current to t;he stepping motors 32, 34, 36 and 38.
The above-mentioned electrical differential action is controlled through a steering-wheel connected differential con-troller 72 which transmits signal Erequency differential control regulated by turning the steering wheel through a connection 74, variable frequency generator 76, connection 78 and right-hand side stepping frequency regulator ~0 through the connect:ion 82 to the regenerative braking current receiver 64 and through the connection 84, left-hand variable frequency generator 86, con-nection 88, left-hand side stepping frequency regulator 90 and ~nnection 92 to the accelerating and decelerating current con-troller 64. From the latter signals proceed by way of the con-nections 56, 58, 60, ~2 to the right-hand stepping motors 32 and 36 and left-hand stepping motors 34 and 38 at different frequencies, depending upon the direction and amount of tu.rn as governed by the differential controller 72 operated by -the vehicle steering wheel.
The term "a~n~ectiDrl!'erllay consist of a single line or a plurality of lines, as explained in connection with Figures 5 to 9 inclusive.

Power ~o~rce The power source 12 for driving the alterna-tor 16 thxough a ~echanical connection 14 may consist of a conventional internal combustion engine, such as a Diesel engine or gas turbine, either of which is smaller than i5 ordinarily necessary in a conventional motor vehicle which requires such a power source to propel the vehicle from a s-tandstill through acceleration to a high speed, as well as in idling. The power delivered by the power source 12 needs only to be suf~icient to drive the alternator 16 to produce an output therefrom adequate to enable the stepping motors 32, 34, 36 and 38 to overcome the w:Lnd resistance and road friction encountered by the vehicle in level road operation.
The advantage of this constant speed of the Diesel or gasoline engine or gas turbine is that it operates at a much higher efficiency than an engine which is required to ac:celerate and decelerate, as in vehicles propelled directly by conven~
tional internal combustion engines or turbines. Moreover, the emissions produced by such constant-speed engines are very low in contrast to the high emissions produced by variable speed engines. In addition, the constant speed engine gives a better fuel economy than an engine which is called upon to accelerate and decelera~e repeatedly during operation. It is well-known matter of fact, for example, that the efficiency of internal com~- -t bustion engines running continuously at ~onstan-t speed to drive electrical generators in generating plants is nearly twice that of t the best internal combustion engines used in the present-day automobile.
The alternator 16 driven by the power source 12 is a two-phese alternator with an output preferably of 120 amperes in each phase operating continuously at a maximum frequency of 450 cycles per second at a voltage of 60 to 84 volts with the two phases 90 degrees apart. This gives enough electrical output to overcome _g _ the wind resistance and rolling resistance of the vehicle in direct drive, with the output of alternating current delivered directly to the stepping motors 32, 34, 36 and 38 direct-con-nected to each of '~he individual vehiOEle w'heels. The alternator 16 employed in the vehicle propulsion system 10 of this inven-tion must operate at a sufficiently low speed :in revolutions per minute in order to fit the torque curve of a Diesel engine, if so powered. The frequency should be variable between 300 and 450 cycles per second depending upon the revolutions per minute of the power source 12 to which the alternator 1.6 is coupled.
It will be understood, however, that if this re~uired f.requency can be more economically .r efficiently produced through an alternator 16 having a hi'~er speed in revolutions of its rotor, a small turbine may be used as the power source 12 in place of the Diesel engine.
The minimum current output of the alternator 16 would preferably be 20 kilowatts with each of the two phases thereof pxoducing an output of 120 to 170 amperes. While the desired vol-tage produced by the alternator 16 i9 between 6~ and 8~ volts, under special circumstances 120 volts would be preferable inas-much as 120 volts is the voltage used by the aircraft in~ustry in aircraft electrical systems.
The output of the alternator 16 provides alternating cur-rent to be used in driving each wheel by its individual stepping motor 32, 34, 36 or 38 independently through a special solid state control circuit described below. Operation of i.-ts two-phase alternator at approximately 400 cycles per second is required because the special stepping motor 3~, 3~, 36 or 38 described below has a stator with only tw~ rotating but separate magnetic ~ields. One such field attrac-ts the nearby magnet o the rotor, if this magnet is of the opposite polarity, while the second field rcpels that nearby magnet of the rotor if that magnet is of the same polarity.
~ s will be seen in connection with the operation of the invention, in the "direct drive" operation of the in~ention, the stepping motors 32, 34, 36 and 38 are locked into synchronization with the alternator 16, without slippage, hence the alternator 16 must produce a two-phase alternating current to drive this par-ticular type of motor. The vehicle propulsion system 10 (E~igure 1) can therefore be considered as propelled by electronically-commutated stepping motors 32, 34, 36 or 38 which are also capable of operating from an alternating current power supply 16 wherein the frequency and phase of the stator currents are regulrtcd through the variable frequency generators 76 and 86 and silicon-controlled rectifi~rs (Figure 5) to maintain the magnetic fields ~`
at their maximum torque conditions, independent o rotor speed or current frequency supplied. In this manner, -the stepping motors 32, 34, 36 and 38 of the vehicle can operate over a wide range of speeds while supplied with alternating current from the fixed-frequency two-phase alternator 16 or the stepping frequency xegulator 80 or g0.
The storage battery 48 employed in the vehicle propulsion system 10 (Figure 1) needs only to be sufficiently large to as-3~'~

sist the output of the alternating 16 driven by the small con-tinuously~runnlng constant--speed engine 12 during starting and acceleration, the direct current from the st.orage battery 48 bein~ electronieally commutated by the variable Erequency generators 76 and 86 -to deliver direct curxent pulses at the desired frequencies to the stepping motors 32, 34, 36 and 38.
While the vehicle is standing still, the engine or turbine 12 does not slow down and idle but continues to run at constant speed so that the rectified output of the alternator 16 is then used to charge the battery 48. It will also be seen below (Figure 9) that a regenerative braking system 64 has been provided which, during braking operations, employs the s-tepping motors 32, 34, 36 and 38 as generators supplying current which when rectified rechar-ges the battery 48.

Solid-State Control System for Output of Fixed-Fre~uency_ wo-Phase Alternator In Figure 5 there is shown the solid-state control system, generally designated 600, which supplies full-wave direct current from the two-phase alternator 16 to energize and control the step-ping motors 32, 34, 36 and 38 of Figure 1 for ~idirectional rotation of the vehicle wheels. Figure 5 thus represents the change in the full-wave circuit 220 in Figure 26 of my above-mentioned previous patent ~o. 873,514 to adapt it to the recep-tion of the two-phase output from the two-phase alternator 16 herein. Use is made in Figure 5 herein of the same reference numerals from 147 to 382 or corresponding parts as :in Figure 26 of my previous patent No. 873,514 of June 15, 1971 for the con-venience of those skilled in the art, and who are hereby xe ferred thereto in order to avoid apparently needl~ss repetltion and duplication oE description. Furthermore, since the reference numerals in my said previous pa-tent 873,51~ end at 568, to avoid any possible confusion the reference numerals used in the remainder of the present specification and drawings start at 600 and remain thereabove.
From Figure 5 is will be seen that -the present circuit 600 is generally si.milar to the circuit 220 of my said prior patent 873,514 but divided into different portions because of the two-phase alternator 16 rather than the single-phase alter-nating current input or current supply source in my s~id prior patent 873,514. For a detailed description of the elements of the circuit 600 shown in the present Fiyure 5, and the generally similar circuit 220 in Figure 26 of my said patent 373,514, reference is made to my latter prior specification.
In my improved circuit 600 ~Figure ~) a subcircuit makes use of the left-hand upper half, renu~ered 602 of my patent circuit 220 for receiving the output 606 of the first phase of the alternator 16, whereas an additional subcircuit corresponding to the right-hand upper half, renumbered 604, receives the out-put 608 of the second phase thereof. The entire circuit 600 provides for a separate transmission of electrical energy to the stepping motors 32, 34, 36 and 38 by the provision of pulses of direct currerlt to th0 two stator circuits for each wheel, each circuit creating alternate north and south poles. In par-ticular, the output of the first phase 606 of the alternator 16 is connected -to the first group 602 o~ silicon-controlled rectifiers 276, 278, 280, 282, 376, 378, 380 and 382, which 9upply current to the stator windings 147 of the s-tepping motors 32, 34, 36 and 38, whereas the second group 604 of silicon-con-trolled rec-tifiers 28~, 290, 292, 29~, 388, 390, 392, 394 receive the OUtpllt of the second phase 608 of the alternator 16 from the connections 604 thereof and supply di.rect current pulses to the second stator windiny 151 of~each such stepping motor. The proper timing of these pulses to stator winc~ings 147 and 151 requires an adjustment oE the times the "delay lines"
retard the shut-off impulses over the reed switches 306 and 308 to the 'IN0R'' logic modules 272, 274, 284, 286.
As stated above, in order to achieve the desired great savings in petroleum fuel, the power plant 12 of the present in-vention is undersized and insufficient to enable the vehicle to accelerate at a needed rate, for instance, to enter high speed traffic lanes safely on expressways or to ascend steep grades.
It is therefore necessary to boost the output of the stepping motors 32, 34, 36 and 38 during acceleration and on grades to more than double their output in 'IDirect drive". To accomplish this (Figures 10 and 11) third and fourth windings 647 and 651, in addition to the windings 147 and 151 are provided on alternate stator pole pieces 14~ and 146 of stepping motors 32, 34, 36 and 38. These additional third and fourth windings 647 and 651 are fed p~l~a~i~g direct current impulses from the storage battery 48 by using, in Figure 10, a slight modification of the wiring diagram Cc~c~
shown in Figure 9 of my above-mentioned patent~ where-in the block 20 labelled "A.C. Power Source" is replaced by "D.C.
Power Source", namely the storage battery 48. To this circuit is added the '~commutating capacitors" necessary to temporarily shut off the silicon-controlled rectifiers and their network. In this manner, a square wave output is supplied to the stepping motors 32, 34, 36 and 38, aided in starting and accelerating by direct current from the storage battery 48 caused to pulsate at the proper fre~uency as controlled by the variable frequency generators 76 and 86. For forward motion o~ the vehicle, the positive half of the square wave is used to travel in a revexse direction, such as in backing, the positive half of the square wave is suppxessed and only the negative half is supplied -to the line 248.
When the vehicle attains a speed of 44 to 45 miles per hour, the circuitry shifts over to direct drive of the stepping motors 32, 34, 36 and 38 by the alternator 16, as shown in Figures 6 and 8, which locks each of the sta-tor windings 147 and 151 directly in synchronism with the alternating current output of the alternator 16. In Figure 8, the designation 147 designates the first set of pole piece windings of each s-t~p-ping motor in series, whereas 151 designates the second set of pole piece windings in series. The four additional "~OR" modules 610, 612, 614, 616 when energized through the line 635 (Figure 6) will shut off the silicon-controlled rectifiers 276, 278, 380, 382 in the first phase 606, but the remaining sil.icon-controlled rectifiers 280, 282, 376 and 378 will ~onnect the motors 32, 34, ~:~3~

36 and 38 directly to the first phase of the alternator 16 when in "direct drive". The remainlng four additional "NOR" modules 618, 620, 622 and 624 will shut off the silicon-controlled rec-tiEiers 292, 29~, 388 and 390 in the second phase 608, but the remaining silicon-controlled rectifiers 288, 290, 392 and 394 will connect the motors 32, 34, 36 and 38 directly to the second phase of the alternator 16 when in "direct drive". ~ow the step-ping motors 32, 34, 36 and 38 are operating as synchronous motors, but this can only happen when -the speed of the vehicle has reached the minimum constant speed of the alternator 16 and the phase of the motors is in step with the alternator. Otherwise, the refer-ence numerals in the Figures 6 and 8 correspond to those in Figure 26 of my said prior patent 873,514.

Lo~ic Circuitr for Placin All Wheels in Direct Drive or Y _ _ q . _. .
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In order to extend the logic circuitry of Figure 5 to cause the logic circuits thereo:E to enable the placing of all iour traction wheels of the vehicle either in a direct-drive condition or in a free-wheeling condi.tion, the logic circuit shown in ~he lower half of Figure 5 has been modiied in ~igure 6 by adding six reed switches 626, 628, 630, 632, 634 and 636.
Four of th~se additional reed switches, namely the reed switches 626, 628, 630 and 632 are normally closed and when not energized let current run from the reed switches 306 and 308 of the l'NOR"
modules 272, 274, 284 and 286 which normally remain in the step-ping condition.

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When, however, the vehicle is in a "direct drive" con-dition, and when electric power is directecl to the four reed ..
switches 626, 628, 630 and 632, they interrupt the Eour lines so that any current which would otherwi.se come through the reed swi-tches 306 and 308 is now interrupted. The effect of this oc-curence is that the "NOR" modules 272, 274, 284, 286 stay in a conducting condition regardless of which side of the flipflops 262 and 264 i9 conducting. Because these "NOR" modules are not interconnected through two additional].y normally-open reed switahes 634 and 636, all "NOR" modules will conduct without interruption and all steppiny motors 32, 34, 36 and 38 will become directly connected to the two-phase alternator 16 (Fig-ure 1)~
On the other hand, when free-wheeling is desired (Figure 5), the power to the four additional reed switches 626, 628, 630 and 632 connects the two ~ides of the reed switches 306 and 308 so that wherever output of the flipflop 262 and 264 happens to be "on", that output is also conducted through to the "~O~"
modules, thereby interrupting the conducting condition of all four of the ''N~R" modules 272, 274, 284 and 286. With the cir~
cuitry in this condition, the gates of all silicon-controlled relays are without current, so that no current can flow through to the stators of the stepping motors 32, 34, 36 and 38.

~eqenerative Brakin~ Actlon In the circuit shown in ~igure 26 o~ my above-mentioned prior Canadian patent 873,514, two "NOR" modules are in a con-ducting condition in their stepping arrangement, namely "NOR"

modules 272, 284, 274 and 286, such conduct;ing being in sequence when stepping is occuring in a :Eorward direction but in a reverse order when stepping is Occur~ng in a reverse direction. When a step is completed, however, the power from the flip-1Ops 262 and 264 is also conducted through the ~wo reed switches 306 and 308 and through the delay lines between these reed switches, the prior activated "NOR" module which is in stepping condition.
This occurrence produces a holding orce in the halE circuit of the stator of the motor 32, 34, 36 or 38, without starting the ~10 next step.
Should the next step be slower than the previous sequence of steps, the rotor of the particular stepping motor 32, 34, 36 or 38 will be subjected to a stronger retardation through the holding force. Should the vehicle go faster than the impulses ar riving on line 248 (Figure 5), that holding force will be over-come and the particular motor 32, 34, 36 or 38 will then act as an alternator as well as a brake. Either of the stators with windings 147 or 151 will now pxoduce a braking Eorce upon the traction wheel of the vehicle. Should -this braking force st~ll not be sufficient and the impulses arriving in line 24~ (Figure 5) go down to zero speed, then the stator windings 147 and 151 of either front wheel 32 or 34 will be first connected in paral-lel and then in series, as shown in Figure 9. By -this series ar-rangement the output of the stepping motors is increased and the maximum braking force consequently created.
The stator windings 147, 151, 647 and 651 o the rear ~L3~

wheel stepping ~otors 36 and 38 are connected in parallel, how-ever, because the braking efort at the rear of the vehicle must be less than that occl~ing at the front of -the vehicle. As shown in E'igure 9, all of the four groups of stat;or windings 147 and 151 are connected individually to four adjustable step-up trans-formers 638, ~40, 6~2 and 644 to raise the generated output vol-tage to be always higher than the voltage of the storage battery48. This generated and transformed alternating current voltage then passes through four ull-wave rectifiers 646, 648, 650 and 652 of the rectifier assembly 68 (F'igures l and 9). The output of these rectifiers is preferably returned to the storage battery 48 through the connection 70 by way of an adjustable rheostat (not shown), thereby controlling the maximum braking force o~
each motor 32, 34, 36 and 3~. This arrangement not only prevents skidding;and the pulling to one side of the street or road but also (Figure g) results in the addition of four levels of braking force available, not counting the ree-wheeling condition. In a truck or tractor-trailer combination vehicle, more motors and controls are thereby available for the possible preven-ting of "jack-knifing". However, in this latter arrangement, sensors for the slipping and conse~uent stalling of the traction wheels during braking must be provided~

~lectronic Differentia~ tem .. .. _ . ~ _ In Figures 1 and 7 are shown the arrangemen-t for providing electronically a differential p~.rformance of the vehicle wheels on opposite sides of -the vehicle corresponding to-the action of a mechanical differential mechanism in a conventional vehic]e.
Figure 7 al90 uses -the same reference numerals as Figure 5 and as Figure 26 in my paten-t 873,514. In order to perform a turn, such as in roundlng a turn in the roadway or turning a corner, the wheels on the opposite sides of -the vehicle must necessarily be travelling at slightly different speeds. According to the present invention, this electronic differential is governed by the steering gear 92 of the vehicle. Depending on the rolling radius of the tires and the an~le of the steering arm to the lo right or left, the variable frequency generator 76 or 86 for the right-hand or left-hand side respecti.vely causes the frequency of the square wave signal being fed into the line 248 (Figure 5) to be slowed down if on the inside of the curve or corner while at the same time the wheels on the outer side of the curves are -turning more rapidly as governed by the higher frequency of their respective stepping motors. When the vehicle is travelling in a straight-forward ~irection, however, khe frequencies from the variable frequency generators 76 and 86 are of ~urse equal.

Chassis Suspension for Stepping Motors of the Vehicle ~he preferred front and rear suspensions 654 and 656 of the stepping motors 32, 34, 36 and 38 in a typical vehicle chas-sis 657 are shown diagrammatically in Figures 2, 3 and 4. ~he suspension 654 or 656 consists of two spot-welded front and rear suspension arm assemblias 658 and 660 which are hinged at front and rear at 662 or 664 on the center line 655 of -the vehicle.

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The pi~ot axis 662 or 664 of this hinge is preferably higher in front than i.n the rear, so that if and when the wheels hit an o~-struction or pothole, they can move somewhat backward on the up-stroke thereof. Such action softens the impact~ because the cen-ter line drops below -the centers of the wheels and consequently prevents scuffing and uneven wear on the tires. The stepping motors 32, 34, 36 and 38 for the traction wheels 666, 668, 670 and 672 respectively (Figure 2) are fastened to the extension arm assemblies 658 or 660 and pivot around the ~ame p~vot axis 662 or 664 on the center line 665 of the vehicle 657~ The distance at the -top between the housings of the two adjacent motors 32 and 34 or 36 and 38 is so dimensioned that t'ne axle will encounter the chas-sis frame (not shown) ahead of the housing, thereby ta~ing up the play allowed. In the downward stroke, however, the axles are limited in -their travel by shock absorbers (not shown). A heavy duty compression spring 674 (E'igure 4) connected between upstan-ding arms 676 and 678 on the housings of -the mo-tors 32 and 34 or 36 and 38 eliminates the need for front and rear sway bars because the compression spring 674 acts in the same manner. The pivot axes 662 and 664 of the hinges 663 and 665 are eccentric and thereby allow adjustme~t for tha toa-in of the front and rear axles of the front and rear suspensions 654 and 656 respectively.
Dapending on the chosen tor~ue output of the motors, the center line of khe motor can lie higher than khe centar :Line of the wheels and the spur gear on each wheel would achieve a mec--hanical advantage. The motors 32 and 34 for the front axle are ~l3~3~

fastened to the suspension arm assembly 654 but would each have a conven-tional constant velocity universal joint 675 so as -to permit the kingpin to have the re~uired inclination for camber and caster.
By being anchored at the top of the apron, the kingpin would swing practically vertically and not in a circular arc like the rear wheel. Each such hinye 663 or 665 (Figures 2 and 4) is anchored at front and rear to the chassis frame and all of the wheels swing around the correspondingly low hinge axis 662 or 664 on a swinging arm assembly 658 or 660 that is much longer than those in presen-t production practice. As a result of the above-mentioned construction, the ride of -the vehicle 657 is improved and any side sway is eliminated.
Summarizing the present invention, the block diagrams of Figure 1 and Figures 2, 3 and 4 show an electrical train 10 for independently driving each wheel 666, 668, 670 and 672 of the ` vehicle 657 and for braking each such wheel sepajrately~ ~irect drive supplies alternating current from the alternator 16 either directly to the stepping motors 32, 34, 36 and 38 or through the two-phase full wave rectifier 46 to the storage battery 48. The charge monitar 50 shuts off the internal combustion engine 12 when the battery 48 is fully charged or when it begins to develop gassing, which indicates that the battery 48 is almost fully charge~ and would be damaged if overcharged.

O~eration To s-tart the vehicle from a standstill, the operator by means of the accelerator pedal (not shown) orders the diferential controller 72 (Figure 7) to start sending positive stepping sig-nals or pulses from the right-hand or left-hand variable frequency generators 76 and 86 through the stepping controls ~0 and 90, thereby energizing these controls so as to send electric current to the sta-tors oi all four motors 32, 34, 36 and 38. This dif-ferential controller 72 is connected to the conventional steering control arm (not shown) of the front wheels of the v~hicle by means of a position sensor (not shown) which indicates if a dif-ferential speed should exist between the right-hand and left-hand set of wheels.
The speed of outgoing stepping signals or pulses is con-trolled through a conventional accelerator pedal which, when depressed, sends a lower or a higher voltage to the variabla frequency generators 76 and 86.
When the vehicle has reached the speed o~ approximately 45 miles per hour, the "direct drive"control" (Figures 5, 6 and 8) connects all motors 32, 3~, 36 and 38 to the two-phase alter-nator 16 so that all these motors run at the same speed as the alternator 16 in a synchronous relationship. In this "direct drive" condition of operation, no current is drawn from the bat-tery ~8, hence the vehicle upon long trips is independent of -the size of the battery. When -the position of the accelerator pedal signals a slowing down of the speed to the stepping motors 32, 3~, 36 and 38, the revolving magnetic field in each stator there-o~ also slows down, with the result that the rotor thereof also at-tempts to slow down, consequently slowing down the vehicle 657. Should the position o~ the accelerator pedal indicate zero speed, namely a halt of the vehicle, and thereby loc~ the magnetic fields of the stators of the steppiny motors 32, 34, 36 and 3~, the permanent ma~nets in the rotor of each of said motors will generate an alternating current in each stator. This alternating current is rectified in the regenerative brakiny rectifier 64, 68 as described above, an~ returned to the storage battery 48 to recharge the latter.
Conventional hydraulic four-wheel disc brakes are pre-ferably retained in this vehicle 657 to serve as additional safety brakes. Furthermore, in a tractor trailer combination, if a stepping motor of the type herein described is provided for ~ach wheel of the tractor and ~or all. wheels of the trailer, it is possible to drive such a tractor-trailer combination in the same manner as an electric interurban train where each axle group has its own electric motor, and a single controller con-trols all motors. Finally, as there is unused space beneath such a trailer chassis, a large storage battery can be convenien-tly installed in that space. As a consequence, a smaller trac-tor is thereby able to haul a larger load and, at the same ~ime, a similar saving o~ petroleum fuel is achieved by charying the battery from an electric public utility energy outlet at each terminal station.
Figures 12 and 13 show a portable solid fuel electric power plant, generally designated 710, consisting yenerally of :~3~

a duplex combustlon unit 712 adapted to contain and burn the combustible solid Euel F, such as wood blocks or fragments, and to deliver the hot power gas thereo~ to a power turbine 714 which drives, through a reduction gear set 716, an altexnator 718 which produces the electric current desired. Compressed air for aiding and accelerating the combustion of the solid fuel F is pro-vided by a power-driven air compressor, generally designated 720, connected to the combustion unit 712. Combustible starting fluid, such as propane, for initiating combustion of the solid fuel E' is supplied by a combustible yas supply unit 722, also connected to the combustion unit 712.
The duplex combustion unit 712 consists of two identical single combustion units 724 and 726, only one of which is placed in operation at a given time, the other such unit being filled with solid fuel F and held in reserve until combustion has used up substantially all of the solid fuelFF in the other single com-bustion unit, whereupon the secand combustion unit is placed in operation and the first combustion unit is filled with solid fuel F at the next opportunity. Each combustion unit 724 or 726 con-sists of a vertically-elongated combustion receptacle or combus-tion pressure vessel 728 of heat-resistant ma-terial, such as steel, with cylindrical lower and upper walls 730 and 732 o~
different diameters joined to one another by a frusto-conical intermediate wall 734 and enclosing a combustion chamber 735.
circular grate 736 is mounted between the walls 730 and 732 at their junction, the lower wall 730 thus providing an ash receiver L3~

738 closed by a bottom wall 740. The lower wall 730 is flanged at its lower end for thc attachment of the bottom wall 740. To simpli:Ey the showing the combustion receptacle 728 is shown as . single-walled whereas in actual practice it would be lined with a suitable refractory material such as fire clay for heat resis--tance and also surrounded by fire-resistant insulating material (not shown) for insulation.
The upper end of the upper wall 732 is flanged for the reception of a top plate or cover plate 742. Lika the walls 734 o and 732, the top wall 7~2 :Ls also pre~erably double-wall.ed and preferabl(y lined with refractory material, such as fire clay for heat resistance and insulation. The top wall 742 is centrally apertured for the reception of a pressure relief valve 744. The bottom wall 740 is clamped to the lower wall 730 by any suitable clamping means and is preferabl~ hinged or otherwise pivoted or slidably mounted by conventional means, to enable the ashes to be dumped from the ash receiver 738 into a suitable ash pit at the location of ~he fuel replenishment station. The solid fuel F is preferably wood fragments which are ordinarily waste products of saw mills or other lumber producing or working establishments, saw dust being a common example of such subdivided or particulate wood. Such subdi.vided or fragmented wood contains a great amount of latent energy which is released slowly rather than explosively during combustion i.n a stead flow of hot power gas. Combustion is initiated by a combustible starting fluid, such as propane, con-tained in a tank 746 and supplied through a conduit 748 and a con~Jentional control and check valve 750 and thence by two con-duits 752 (Figure 13) -to duplex burners 75~ below each of which is a spark plug 756 connected by a conventional conductor cable (not sh~wn) to a conventional source of high terlsion electricity (not shown) or a platinum wire glow pl~g similar to ones used in gas appliances.
Also connected to the control and check valve 750 is the outlet or discharge duct 758 of the frusto-conical casing 760 of the compressor 762 at the lower end o:E the power-driven air com-L0 pressor '720. The upper end of the casing 762 is joined to the in-take duct 764 thereof and receives air through an intake filter 766 by way of:.an air throttle valve 768. Mounted on the upper end of the air compressor casing 760 and air intake duct 764 is the air compressor drive motor 770 which may consist, for example, of an electric motor or turbine.
~ncircling the lower end of the intermediate wall 734 o~
each combustion unit 724 or 726 is a power gas discharge conduit or manifold 772, each of which opens into an outlet conduit 774 which in turn discharge the power gas into a joint discharge con-duit 776 containing a power gas throttle valve 778. The joint dis-charge conduit 776 is connected to the intake portion 780 at one end of the conventional power gas turbine 714. The power gas, af-ter passing through the power turbine 714 and imparting rotation to its successive rotors and between i-ts intervenang stators (not shown) emerges at its e~haust portion 782 at the opposite ends of the turbine 714. This action imparts rotation to the shaft 784 extending between the power turbine 714 and the reduction ;~3~

gear set 716. This gear set 716 may consist, for example, of that gearset di.sclosed and claimed in my Uni-ted States Patent ~o. 4,155,276 issued May 22, 1979 for High--Ratio Sp0ed-Reduc-tion Transmission. The output shaft 786 of -the reduction gear box 716 extends therefrom to the two-phased alternator 718 which generates 400-cycle alternating current in response to the rotation of the shaft 786. The alternating current generated as a result of this action is delivered from output terminals 788 and 790 through suitable conductor cables to the place of utilizat.ion such as, Eor example, to the distribution ci.rcuit of the principal form of my present invention described above with reference to Figures 1 to 11 inclusive herein.
The operation of the portable solid fuel electric power plant of the modification of the present invention shown in Figures 12 and 13 of the drawings hereof is believed to be self-evident from the foregoing description of its construction and arrangement. ~n one of its intended uses, the components of this power plant are mounted on the vehicle to be propelled, with the duplex combustion unit 712 mounted on the rearward and thereof where the surplus heat will be dissipated most efficiently. Each oE the combustion receptacles 728 is filled with solid fuel F, preferably a mainly cellulose material in the form of subdivided wood fragments, wood blocks or wood sawdust. The tank 746 of the combustible starting gas supply unit 722 is filled with the com-bustible starting gas such as propane or other suitable combus-tion-initiating substance, and the elec-tric drlving motor 770 of the air compxessor 720, having been connected to the vehicle storage batteries is set in operation or, ln the alternative, the turbine substituted for it is placed in operation. In either event, compressed air is discharged by the air compressor 60 through the outlet duct 758 and control and check valve 750 to the conduit 752 of the combustion unit 724 or 726 to be initial-ly used, with the other combustion unit 726 or 724 temporarily ~, shut off and held in reserve. The spark plug 756 is then ener-gized to ignite the star-ting gas flowing through the particular conduit 752 which is intended to be used at the momen-t, causing the burner 754 thereof to emit ~lames from the thus-ignited starting gas. These flames, in turn ignite the solid fuel F
which, when sufficiently ignited to be self-sustainlng,in com-bustion, no longer require the supplying of the starting gas from the tank746, whereupon the supply thereof to the conduit 748 i9 terminaked.
Meanwhile, the hot co~ustion power gas emitted by the burning solid fuel F is discharged through the power gas dis-charge conduit 772 and thence through the outlet conduit 774 into the joint discharge conduit 776 past the power gas throttle valve 778 into the intake portion 780 of the power gas turbine.
This action by the thrust of the hot combustion power gas bet ween the blades or vanes of the successive rotors and the stators imparts rotakion at high speed to the shaft 784 connecting the power gas turbine 714 to the reduction gear set 716. The latter reduces the speed of rotation to that re~uired to operate the ~3~

alternator 718, which thereupon delivers 400-cycle alternating current to its output terminals 788 and 790 for further trans-mission to the place of utilization mentioned above.
More particularly, in the propulsion of an elec-tric vehicle, the operation is as follows. When the driver ge:ts in-to the car, he turns the ignition key, whereupon the valve 750 opens to let propane gas flow from the tank 746 into the corn-hustion chamber 735. This is now ignited by a spar]~ plug and burns the wood chips. After the woo~ chips have well caught fire, a heat sensitive switch (not shown) shuts off the gas and the spark plug. This also happens if the gas fails to ignite. Af-ter reaching a pressure above atmospheric pressure, the throttle 768 opens to the compressor drive turbine 770, or optionally the electric motor 770 starts the compressor 762, which now blows enough air into the combustion tecsptacle 728 to admit sufficient oxygen in order to continue the burning process of the wood. Even if this starting procedure introduces a kime lag of 10 to 15 minutes, the driver meanwhile can start the car and propel it temporarily with battery power, hence will not be required to wait. ;~
~ soon as the pressure through the threefold expanding hot air has reached the re~uired level, and the opening of the main or power throttle 778 allows the full power output of the power turbine 714, the alternator 718 is cut in and thereupon regenerates its 300-400 cycle two-phase alternating current to help accelerate the car to full speed, as explained above in connection with the principal form of this invention. As soon as ~ull speed :Ls reached, the battery current for temporary propulsion is shut o~. The alternator 718 and the ~our stap-ping motors 32, 3~, 36 and 38 are so sized that they can over-come the rolling and wind resistance o~ the car. As also ex-plained above, when the vehicle is decelerating, the energy of deceleration will be recuperated and will flow into the battery.
When the vehicle is stopping or waiting at a traffic light, the full output of the alternator 718 will ~uickly recharge the vehi.cle propulsion battery so that the battery power thereoE
can be subse~uently used ~or accelerating the vehicle.
The air compressor 762 and its turbine or motor 770 are completely detached ~rom the power turbine 714. Their duty is solely to mai.ntain a certain predetermined prassure in the com-bustion chamber 735 and in the adjacent combustion receptacle or pressure ve$sel 728, for example 80 to 100 p.s.i. When this pres-sure is reached, a pressure switch (not shown) closes the valve 768 in the air intake 766 o~ the compressor, as well as the throttle or switch 768 ~or the compressor or motor 770 respec-tively so that at this time no air is pumped into the combustion chamber 735. When the pressure in the combustion chamber 735 has decreased to the permissible minimum p.s.i., the throttle or switch 768 at the compressor turbine or motor 770 opens again, as well as at the throttle at the air i.ntake of the air compres-sor. Air is thereupon pumped into the combustion chamher 735, thus adding oxygen thereto, and through the concurrent burning of the wood particles, pieces or blocks, the pressure is again rai.sed to the designed 80 p.s.i. For example, let it be assumed that while driving at 50 m.p.h. the compressor unit 720 pumps air into the combustion chamber 735 for about five seconds, and :
then closes for about 15 seconds. Under -these circumstances, the fuel wood F in the combus~ion chamber 735 remains hot but it does not burn.
Even the water content of wood is not a drawback to this power plant because such water is evaporated at 100 p.s.i. to produce steam, which assists the hot power gas in turning the rotor of the power turbine 71~. ~oreover, the ~uality oE the wood used as the fuel F is not important. A11 kinds of wood can be used, e~en branches, tree stumps, dead wood, in fact any burnable part of the tree, soft and hard wood. For convenience of han~ling, the wood fuel may be cut into small blocks of about four inches s~uare. Such wood may also be bagged, like charcoal for backyard grills.
When the retail price of scrap wood is converted i~nto British thermal units and compared with the retail price of gasoline, the cost of such wood fuel F turns out to be equivalent to about 20 cents a gallon. Furthermore, there is no sales tax nor highway tax added, as with gasoline, so that the cost of such wood fuel is still much ].ess than the dollar a gallon we are now paying for gasoline fuel~ As a conse~uence, wood is not only an alternate and renewable fuel but it is also economical and much safer to handle than flammable a~d explosive gasoline.

-~t,g ,~ q ~y~

Conventional gas turbines require a certain time to build up adequate pressure, and this is detriment;al to stop-and-go traf-fic. As explained above in connection with the principal form of ~he inven-tion, battery power is used to overcome this problem.
The wood chips or blocXs used to heat the compressed air and to produca the power gas in each combustion chamber 728 can be the waste of the timber industry which, a-t the present time, is completely los-t. The U.S. logging industry estimates this waste at 120 million dry tons annually. This waste could produce the ~0 equivalent energy in the present power plant of ~00,000 barrels o~ oil daily.
It is ordinarily assumed that a pound of dynamite possesses more energy than a pound of wood, whereas the reverse is actually the case. A pound of dynamite holds only half the energy of a pound of wood. A11 that dynamite does is ~elèase its energy in,a split second, whereas slow-burning wood takes a much longer time to do so. Moreover, 2.5 pounds of wood contains exactly the same amount of energy as one pound of gasoline.
The fuel F may also consist of the processed cellulose, w~s~e material known as "Biomass" fuel which includes not only wood scraps and sawdust but also sugar cane, bamboo, chaparrall, corn cobs and eucalyptus preferably made into highly-compressed fuel briquettes. One such continuous-extrusion machine for pre-paring fuel briquet-tes from such waste materials is described in an article in the journal Industrial Research Development of page 37 of the December 1978 issue entitled "Machine Cuts Biomass Fuel Cost." Thls machine is said to convert wood waste and "every known kind of biomass residue" into such brique-ttes which hurn with very little ash and wh:ich make use of waste ma-terial which .is otherwise almost always thrown away, as by being buried or burned.

Claims (10)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. An engine-driven-alternator individual-wheel motorized electric propulsion system for a four-wheel motor vehicle provided with a steering mechanism, said system comprising an engine-driven two-phase alternator having a two-phase alternator output, a plur-ality of electric stepping motors adapted to be drivingly con-nected one to each vehicle wheel and having motor inputs, each stepping motor having a rotor and also having a stator with a multiplicity of pole pieces arranged in first and second sets dis-posed in alternate sequence with the pole pieces of each set having alternate opposite windings imparting alternate opposite polarities to the stator pole pieces of each set upon energization thereof, each stator pole piece having a first winding adapted to be energized by pulses of rectified alternating current and a second winding thereon adapted to be energized by pulses of direct current, a storage battery, a pulse-responsive electric power system including a plurality of gate-controlled rectifiers having power current input means and also having power current output means, a stepping motor control circuit interposed between and connecting said alternator output to said motor inputs and in-cluding switching means connected to the gates of said gate-con-trolled rectifiers and responsible to the reception of positive or negative pulses for selectively energizing said first and second windings of said stator pole pieces separately and simultaneously and thereby effecting step-by-step rotation of said rotors, variable frequency generating means electrically connected to said pulse-responsive electric power system including said plurality of gate-controlled rectifiers, and a frequency con-trol circuit for selectively controlling the frequency output of said variable frequency generator means.

2. An engine-driven-alternator individual-wheel-motorized electric propulsion system, according to claim 1, wherein said variable frequency generating means includes a right-turn variable frequency generator and a left-turn variable frequency generator connected in frequency-regulating relationship to the right side and left side stepping motors respectively, and wherein there is provided a variable frequency generator control device connected to the vehicle steering mechanism and responsive to the operation thereof to effect differential variation of the frequency of elec-tric current supplied to and proportioned between said right side and left side stepping motors.

3. An engine-driven-alternator individual-wheel-motorized electric propulsion system, according to claim 1, wherein engine control means is provided regulating the speed of said engine and alternator to rotate at a substantially constant speed and con-stant alternating current frequency output respectively.

4. An engine-driven-alternator individual-wheel-motorized electric propulsion system, according to claim 3, wherein the vehicle is provided with an operator-actuated vehicle speed regulator, wherein the output of said alternator, after chan-ging its frequency through switching, is connected to said first windings of said motor stators, and wherein said swit-ching means connects alternator-synchronized pulsating direct current from said storage battery to said second stator windings in response to a power demand from the attainment of a predeter-mined vehicle speed or acceleration.

5. An engine-driven-alternator individual-wheel-motorized electric propulsion system, according to claim 1, wherein said gate-controlled rectifiers include a first set of full wave first-phase rectifiers connected to receive the first-phase output of said two-phase alternator and also include a second set of full-wave second phase rectifiers connected to receive the second phase output of said two-phase alternator.

6. An engine-driven-alternator individual-wheel-motorized electric propulsion system, according to claim 1, wherein means is provided for dividing the alternating current output of the vehicle frequency generators into positive and negative polarity half waves, and wherein means is provided for suppressing the half waves of one polarity corresponding to forward motor driving operation and retaining the half waves of the opposite polarity corresponding to rearward motor driving operation whereby to effect selective backing of the vehicle.

7. An engine-driven-alternator individual-wheel-motorized electric propulsion system, according to claim 1, wherein there is provided a second set of full wave rectifiers with one such second set rectifier having an input connected electronically to each stepping motor to receive alternating current therefrom during vehicle speed braking retardation with said stepping motors driven as alternators by their respective vehicle wheels, and with said second set rectifier having an output connected to said storage battery in recharging relationship therewith, and wherein said braking retardation means is provided for diverting the output of said engine-driven alternator to said gate control rectifiers and thence to said storage battery.

8. An engine-driven-alternator individual-wheel-motorized electric propulsion system, according to claim 1, wherein there is provided a storage battery changing monitor electrically connected in engine speed regulating relationship between the engine and said storage battery for reducing the speed of said engine and consequently reducing the correspond-ing output of said alternator in response to the indication by said monitor of said storage battery having attained a fully charged condition.

9. An engine-driven-alternator individual-wheel-motorized electric propulsion system, according to claim 1, wherein said engine is an internal combustion engine.

10. An engine-driven-alternator individual-wheel-motorized electric propulsion system, according to claim 1, wherein said engine is an expansive fluid turbine.