WO2018166106A1

WO2018166106A1 - Power system of extended-range pure electric vehicle and control method

Info

Publication number: WO2018166106A1
Application number: PCT/CN2017/090753
Authority: WO
Inventors: 李璟瑜; 孟明华
Original assignee: 江苏卡威汽车工业集团股份有限公司
Priority date: 2017-03-17
Filing date: 2017-06-29
Publication date: 2018-09-20
Also published as: CN107097656B; CN107097656A

Abstract

A power system of an extended-range pure electric vehicle, comprising: a power battery pack (1), an engine (4), a fuel tank (2) for supplying fuel to the engine (4), a generator (5) for converting kinetic energy of the engine into electric energy, a power distribution controller (8) and a drive motor (6) for driving the vehicle to run. The power battery pack (1), the generator (5) and the drive motor (6) are all electrically connected to the power distribution controller (8). Power supplied by the power battery pack (1) and the generator (5) is supplied to the drive motor (6) by means of the power distribution controller (8). When the power of the power battery pack (1) is insufficient, the engine (4) starts so as to drive the generator (5) to generate electricity, and supply the electric power generated by the motor (5) to the drive motor (6) and charge the power battery pack (1). The described system may charge a battery pack, distribute energy intelligently and carry out maintenance of the battery pack according to the driving situation of a vehicle, and may prolong the mileage of an electric vehicle and the service life of the battery pack. Also provided by the present invention is a control method for the power system of the extended-range pure electric vehicle.

Description

Power system and control method for extended-program pure electric vehicle

Technical field

The invention belongs to the technical field of electric vehicles, and particularly relates to a power system and a control method for an extended-program electric vehicle.

Background technique

In the future, when national and local subsidies for new energy are reduced, pure electric vehicles have the following obvious advantages. 1. 80% of household passenger cars are used for commuting, picking up children to go to school, and outings in the city. This process can all use pure electric drive to achieve zero emissions. 2. In the case of perfect charging facilities in the future, 80% of the journey can use power batteries and external power supplies. 3, urban logistics vehicles, logistics distance generally does not exceed 100km, in the future after the completion of the charging facilities, almost 80% of the exercise process using external power supply charging. 4, light passenger car, the company's commuter car, the mileage is usually no more than 100km, there is enough time to charge. 5. Medium and large passenger cars, if used for commuter shuttles, can meet commuting in the city. At present, electric vehicles are limited by the battery capacity, which is basically limited to short-distance, and it is difficult to improve the cruising range. Therefore, it is urgent to develop an electric vehicle that can compensate for the short driving range due to battery capacity limitation.

Summary of the invention

The present invention is directed to the above problem, and proposes a power system and a control method for an extended-range pure electric vehicle that has a long battery life, a fast charging speed, and can adapt to long-distance operation.

specific plan:

A power system for an extended-range electric vehicle, the system comprising: a power battery pack (1), an engine (4), a fuel tank (2) for supplying fuel to the engine (4), converting kinetic energy of the engine into Electric energy generator (5), power distribution a controller (8), and a drive motor (6) driving the vehicle, the power battery pack (1), the generator (5), and the drive motor (6) are both connected to a power distribution controller (8) Electrically connected, the power provided by the power battery pack (1) and the generator (5) is supplied to the drive motor (6) through the power distribution controller (8); when the power of the power battery pack (1) is insufficient, The engine (4) is started to drive the generator (5) to generate electricity, and the electric energy generated by the generator (5) is supplied to the driving motor, and the power battery pack (1) is charged.

Further, the system further includes a vehicle controller (8) and an engine controller (3), the power battery pack (1), a drive motor (6), an engine controller (3), and a power distribution controller ( 8) is connected to the vehicle controller (8) through a CAN bus, and when the vehicle controller (8) detects that the power of the power battery pack (1) is insufficient, the engine (4) is turned on, The driving motor (6) supplies power and monitors power consumption of the driving motor (6), and when the power consumption is greater than a predetermined value, charging the power battery pack (1) by using a first charging mode; When not greater than the predetermined value, the power battery pack (1) is charged in a second charging mode; the first charging mode is current limiting pulse charging, and the second charging mode is constant voltage charging.

Further, the vehicle controller (8) is preset with m voltage thresholds, which are sequentially increased from the first voltage threshold to the mth voltage threshold, and the vehicle controller (8) is The accumulated number of times of charging of the power battery pack (1) sequentially selects one of the threshold values from 1 to m from the preset voltage threshold as a voltage threshold for determining whether the battery pack is insufficient, when the battery pack (1) When the average battery voltage is lower than the voltage threshold, it is judged that the power of the power battery pack (1) is insufficient.

Further, when the vehicle controller (8) selects the mth voltage threshold, Initiating an activation procedure for the battery pack, the activation procedure comprising the steps of:

(1) limiting the power consumption of the drive motor (6) such that it is not greater than a predetermined value;

(2) discharging a single cell in the battery pack, discharging to an overdischarge cutoff voltage, the overdischarge cutoff voltage being lower than a first voltage threshold;

(3) discharging the battery to the over-discharge cut-off voltage, performing positive and negative alternating pulse current circulation 3-10 times in the vicinity of the over-discharge cut-off voltage, the pulse current is 0.1-0.2C, and the pulse action time is 10- 60s, interval 0-20s;

(4) Constant current charging to the charging cut-off voltage, performing positive and negative alternating pulse current circulation 3-10 times in the vicinity of the charging cut-off voltage, the pulse current is 0.1-0.2C, the pulse action time is 10-60s, and the interval is 0. -20s.

Further, the fuel in the fuel tank (2) may be gasoline, diesel, natural gas, alcohol ether or a combination thereof.

Further, the power battery pack (1) is provided with two external charging ports, and the two external charging ports are respectively used for connecting a 380V fast charging pile or charging with a 220V ordinary power source by using a vehicle charger.

Further, the system has a solar panel (11) electrically connected to the power distribution controller (8); when the vehicle is in operation, the solar panel (11) is The drive motor (6) provides auxiliary power; the solar panel (11) charges the power battery pack (1) when the vehicle is stopped or idling.

A method for controlling a power system of an extended-range electric vehicle, comprising:

When the power of the power battery pack (1) is sufficient, the engine (4) does not work, and the power battery pack (1) is used to power the vehicle;

When the power of the power battery pack (1) is insufficient, the vehicle controller (8) sends Commanding to the engine controller (3), causing the engine (4) to operate to drive the generator (5) to generate electricity, the power generated by the generator (5) to generate power to the power battery pack (1), to power the drive motor, and to be the power battery pack (1) Charging.

Compared with the prior art, the present invention has the following beneficial effects:

1. Avoid excessively large battery weight and total vehicle weight caused by increasing battery capacity in order to increase driving range.

2. An electric hybrid vehicle or an electric oil hybrid vehicle requires two sets of drive systems, and the pure electric vehicle of the present invention only needs one set of drive system, which saves the production cost of the automobile and reduces the overall weight of the electric vehicle;

3. Use the engine to drive the generator to generate electricity, power the car through the power distribution controller and charge the power battery pack, and control the engine to always operate at constant power to improve the fuel utilization efficiency.

4. Monitor the vehicle power demand, determine the charging mode of the battery according to the power demand; the current-limiting pulse charging mode preferentially guarantees the driving mileage in the case of preventing the battery pack from being over-released; the constant-voltage charging mode has a higher battery level when the battery pack is low. The high charging speed quickly restores the power of the battery pack, and the charging speed decreases as the battery pack voltage increases, so that the energy is properly distributed while ensuring constant power operation of the engine.

5. Set a number of different values for the threshold voltage at which the battery starts to charge, to prevent the battery from starting to charge at the same threshold voltage to prevent the battery from generating a memory effect.

6. After a predetermined number of cycles, the activation mode of the battery is activated to eliminate the polarization and prolong the service life of the battery.

7. In the activation mode, lithium is irreversibly embedded in the negative electrode (lithium in part of the SEI film) by pulse circulation at an overdischarge potential, and the lithium salt in part of the SEI film is dissolved to enable it to re-enter the battery charge. During the discharge cycle, the battery capacity is restored; and the pulse is cycled near the charge cut-off voltage, thereby re-forming a stable SEI film, improving the cycle life of the battery;

8. Use solar panels, make full use of natural energy, and intelligently distribute electricity according to the driving situation of the vehicle; preferentially use solar panels to charge the power battery pack, reduce the time for the engine to generate electricity by burning fuel to reduce the emission of polluting gases.

9. Solar panels are installed in the ceiling of the car. In the summer, the solar panels absorb the heat absorbed to generate electricity while reducing the temperature rise caused by the sun inside the car.

DRAWINGS

The present invention will be further described in detail below in conjunction with the drawings and specific embodiments.

1 is a schematic diagram of a power system of an extended-range electric vehicle according to Embodiment 1 of the present invention;

2 is a schematic diagram of a power system of an extended-range electric vehicle according to Embodiment 2 of the present invention.

Among them: 1, power battery pack, 2, fuel tank, 3, engine controller, 4, engine, 5, generator, 6, drive motor, 7, power distribution controller, 8, vehicle controller, 9, charging Device, 10, solar battery controller, 11, solar panels.

detailed description

The invention will now be described in further detail with reference to the drawings. The drawings are simplified schematic diagrams, and only the basic structure of the present invention is illustrated in a schematic manner, and thus only the configurations related to the present invention are shown.

Example 1

A power system of an extended-range electric vehicle as shown in FIG. 1, the system comprising: a power battery pack (1), an engine (4), a fuel tank (2) for supplying fuel to the engine (4), and an engine a generator (5) that converts kinetic energy into electrical energy, a power distribution controller (8), a drive motor (6) that drives the vehicle, a vehicle controller (8), and an engine controller (3); the fuel tank ( 2) The fuel inside is gasoline. The power battery pack (1) is provided with two external charging ports for connecting a 380V fast charging station and a 220V ordinary power source. The single battery used in the power battery pack is a lithium titanate battery.

The power battery pack (1), the generator (5) and the drive motor (6) are all electrically connected to a power distribution controller (8), the power battery pack (1) and the generator (5) The supplied power is supplied to the drive motor (6) through the power distribution controller (8); the power battery pack (1), the drive motor (6), the engine controller (3), and the power distribution control The controllers (8) are all connected to the vehicle controller (8) via a CAN bus.

The vehicle controller (8) is preset with five voltage thresholds, which are sequentially increased from the first voltage threshold to the fifth voltage threshold, and the vehicle controller (8) is based on the power battery pack (1) The cumulative number of times of charging is sequentially cycled from 1 to 5 from the preset voltage threshold to select one of the thresholds as a voltage threshold for determining whether the battery pack is insufficient, when the average battery voltage of the battery pack (1) is lower than When the voltage threshold is described, it is determined that the power of the power battery pack (1) is insufficient.

When the vehicle controller (8) detects that the power of the power battery pack (1) is insufficient, the engine (4) is turned on to supply power to the drive motor (6), and the power consumption of the drive motor (6) is monitored. When the power consumption is greater than a predetermined value, the power battery pack (1) is charged by using a first charging mode; when the power consumption is not greater than a predetermined value, the second charging mode is used as the power battery pack ( 1) charging; the first charging mode is current limiting pulse charging, and the second charging mode is constant voltage charging; the predetermined value is determined according to actual power of the engine and efficiency of the generator.

When the vehicle controller (8) selects the fifth voltage threshold, an activation procedure for the battery pack is initiated, and the activation procedure includes the following steps:

(1) controlling the power consumption of the drive motor (6) such that it is not greater than a predetermined value;

(3) discharging the battery to the over-discharge cut-off voltage, performing positive and negative alternating pulse current circulation three times in the vicinity of the over-discharge cut-off voltage, the pulse current is 0.1 C, the pulse action time is 10 s, and the interval is 0 s;

(4) Constant current charging to the charging cut-off voltage, and performing positive and negative alternating pulse current circulation three times in the vicinity of the charging cut-off voltage, the pulse current is 0.1 C, the pulse action time is 10 s, and the interval is 0 s.

Example 2

Embodiment 2 further adds a solar panel (12) to the ceiling of the pure electric vehicle on the basis of the embodiment 1;

Steps 3) and 4) in the activation process are:

(3) discharging the battery to the over-discharge cut-off voltage, performing positive and negative alternating pulse current circulation 10 times near the over-discharge cut-off voltage, the pulse current is 0.2 C, the pulse action time is 60 s, and the interval is 20 s;

(4) Constant current charging to the charging cut-off voltage, and performing positive and negative alternating pulse current circulation 10 times in the vicinity of the charging cut-off voltage, the pulse current is 0.2 C, and the pulse action time is 60 s, and the interval is 20 s.

It is understood that the specific embodiments described above are merely illustrative of the invention and are not intended to limit the invention. Obvious changes or variations that come within the spirit of the invention are still within the scope of the invention.

Claims

A power system for an extended-range electric vehicle, characterized in that the system comprises: a power battery pack (1), an engine (4), a fuel tank (2) for supplying fuel to the engine (4), and an engine a generator (5) that converts kinetic energy into electrical energy, a power distribution controller (8), and a drive motor (6) that drives the vehicle, the power battery pack (1), the generator (5), and the The drive motor (6) is electrically connected to the power distribution controller (8), and the power provided by the power battery pack (1) and the generator (5) is supplied to the drive motor (6) through the power distribution controller (8); When the power of the power battery pack (1) is insufficient, the engine (4) is started to drive the generator (5) to generate electricity, and the electric energy generated by the generator (5) is supplied to the driving motor, and the power battery pack is provided (1) ) Charging.
The power system of an extended-range electric vehicle according to claim 1, further comprising a vehicle controller (8) and an engine controller (3), the power battery pack (1), and a drive motor (6) The engine controller (3) and the power distribution controller (8) are both connected to the vehicle controller (8) via a CAN bus, and when the vehicle controller (8) detects the power battery pack (1) When the power is insufficient, the engine (4) is turned on to supply power to the driving motor (6), and the power consumption of the driving motor (6) is monitored. When the power consumption is greater than a predetermined value, the first charging mode is used. The power battery pack (1) is charged; when the power consumption is not greater than a predetermined value, the power battery pack (1) is charged in a second charging mode; the first charging mode is a current limiting pulse charging, the first The second charging mode is constant voltage charging.
The power system of the extended-range electric vehicle according to claim 2, wherein the vehicle controller (8) is preset with m voltage thresholds, and sequentially increases from the first voltage threshold to the m-th voltage threshold. The vehicle controller (8) according to the cumulative number of times of charging of the power battery pack (1) from a preset voltage threshold from 1 to m sequentially cyclically selects one of the thresholds as a voltage threshold for determining whether the battery pack is insufficient, and determines the amount of power of the power battery pack (1) when the average battery voltage of the battery pack (1) is lower than the voltage threshold. insufficient.
The power system of an extended-range electric vehicle according to claim 3, wherein when the vehicle controller (8) selects the mth voltage threshold, an activation procedure for the battery pack is initiated, the activation procedure including the following step:

(1) limiting the power consumption of the drive motor (6) such that it is not greater than a predetermined value;

(2) discharging a single cell in the battery pack, discharging to an overdischarge cutoff voltage, the overdischarge cutoff voltage being lower than a first voltage threshold;

(3) discharging the battery to the over-discharge cut-off voltage, performing positive and negative alternating pulse current circulation in the vicinity of the over-discharge cut-off voltage; preferably, circulating 3-10 times, the pulse current is 0.1-0.2 C, pulse The action time is 10-60s, with an interval of 0-20s;

(4) constant current charging to the charging cut-off voltage, performing positive and negative alternating pulse current circulation in the vicinity of the charging cut-off voltage; preferably, circulating 3-10 times, the pulse current is 0.1-0.2 C, and the pulse action time is 10 -60s, interval 0-20s.
The power system of an extended-range electric vehicle according to claim 1, wherein the fuel in the fuel tank (2) may be gasoline, diesel, natural gas, alcohol ether or a combination thereof.
The power system of the extended-range electric vehicle according to claim 1, wherein the power battery pack (1) is provided with two external charging ports, and the two external charging ports are respectively connected to the 380V fast charging pile or utilized. The car charger is charged at 220V normal power.
A power system for an extended-range electric vehicle according to claim 1, said system having a solar panel (11) electrically connected to said power distribution controller (8); The solar energy when the car is running A battery panel (11) provides auxiliary power to the drive motor (6); the solar panel (11) charges the power battery pack (1) when the vehicle is stopped or idling.
A control method for a power system of an extended-range electric vehicle according to any one of claims 1 to 7, characterized in that

When the power of the power battery pack (1) is sufficient, the engine (4) does not work, and the power battery pack (1) is used to power the vehicle;

When the power of the power battery pack (1) is insufficient, the vehicle controller (8) sends a command to the engine controller (3) to cause the engine (4) to operate to drive the generator (5) to generate electricity, and the generator (5) generates The electric energy generates electricity to the power battery pack (1), supplies power to the drive motor, and charges the power battery pack (1).
The control method according to claim 8, said system having a solar panel (11) electrically connected to said power distribution controller (8); when said vehicle is in operation, said A solar panel (11) provides auxiliary power to the drive motor (6); the solar panel (11) charges the power battery pack (1) when the vehicle is stopped or idling.