Detailed Description
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.
A control method of a bidirectional DC-DC converter, a control device of a bidirectional DC-DC converter, and a train according to an embodiment of the present invention will be described below with reference to the drawings.
As shown in fig. 1, a bidirectional DC-DC converter according to an embodiment of the present invention includes a first converting branch, a second converting branch and a third converting branch, the first converting branch, the second converting branch and the third converting branch are connected in parallel with each other, each of the first converting branch, the second converting branch and the third converting branch includes an upper bridge switching tube and a lower bridge switching tube, namely, the first conversion branch comprises a first upper bridge switching tube Q11 and a first lower bridge switching tube Q12, a first node J1 is arranged between the first upper bridge switching tube Q11 and the first lower bridge switching tube Q1, the second conversion branch comprises a second upper bridge switching tube Q21 and a second lower bridge switching tube Q22, a second node J2 is arranged between the second upper bridge switching tube Q21 and the second lower bridge switching tube Q22, the third conversion branch comprises a third upper bridge switching tube Q31 and a third lower bridge switching tube Q32, and a third node J3 is arranged between the third upper bridge switching tube Q31 and the third lower bridge switching tube Q32.
As shown in fig. 1, the bidirectional DC-DC converter further includes a first inductor L1, a second inductor L2, a third inductor L3, and a first capacitor C1, wherein one end of the first inductor L1 is connected to the first node J1, one end of the second inductor L2 is connected to the second node J2, one end of the third inductor L3 is connected to the third node J3, the other end of the third inductor L3 is connected to both the other end of the first inductor L1 and the other end of the second inductor L2, and the first capacitor C1 is connected to the output terminal of the bidirectional DC-DC converter.
When the bidirectional DC-DC converter works in a forward direction, the first upper bridge switching tube Q11, the second upper bridge switching tube Q21 and the third upper bridge switching tube Q31 are controlled to be switched on and off, when the first upper bridge switching tube Q11, the second upper bridge switching tube Q21 and the third upper bridge switching tube Q31 are controlled to be switched on, the first upper bridge switching tube Q11, the second upper bridge switching tube Q21 and the third upper bridge switching tube Q31 respectively charge the first inductor L1, the second inductor L2 and the third inductor L3, and when the first upper bridge switching tube Q11, the second upper bridge switching tube Q21 and the third upper bridge switching tube Q31 are controlled to be switched off, the first inductor L1, the second inductor L2 and the third inductor L3 respectively pass through the first lower bridge switching tube Q12, the second lower bridge switching tube Q22 and the third lower bridge switching tube Q32 to reduce voltage. On the contrary, when the bidirectional DC-DC converter works reversely, the first lower bridge switching tube Q12, the second lower bridge switching tube Q22 and the third lower bridge switching tube Q32 are controlled to be turned on and off, when the first lower bridge switching tube Q12, the second lower bridge switching tube Q22 and the third lower bridge switching tube Q32 are controlled to be turned on, the first lower bridge switching tube Q12, the second lower bridge switching tube Q22 and the third lower bridge switching tube Q32 are controlled to be turned on to respectively charge the first inductor L1, the second inductor L2 and the third inductor L3, and the first lower bridge switching tube Q12, the second lower bridge switching tube Q22 and the third lower bridge switching tube Q32 are controlled to be turned on, and the first inductor L1, the second inductor L2 and the third inductor L3 are respectively controlled to be turned on through the first upper bridge switching tube Q11, the second upper bridge switching tube Q21 and the third upper bridge switching tube Q31.
In an embodiment of the present invention, as shown in fig. 2, the control method of the bidirectional DC-DC converter includes the following steps:
s1: and acquiring the power to be output of the bidirectional DC-DC converter.
S2: and judging a power interval in which the power to be output is positioned, wherein the output power of the bidirectional DC-DC converter is divided into a plurality of power intervals.
It should be noted that the output power of the bidirectional DC-DC converter may be divided into a plurality of power intervals, for example, two power intervals, i.e., a first power interval and a second power interval; as another example, three power intervals, namely a first power interval, a second power interval, and a third power interval.
S3: and controlling the upper bridge switching tube and the lower bridge switching tube according to the power interval of the power to be output so as to control the first conversion branch, the second conversion branch and the third conversion branch to work in turn when the power to be output is smaller than the preset power.
The control of the upper bridge switching tube and the lower bridge switching tube can be the on-off control of the upper bridge switching tube and the lower bridge switching tube.
That is to say, when the bidirectional DC-DC converter works, the power to be output of the bidirectional DC-DC converter is obtained, the power interval where the power to be output is located is judged, whether the power to be output is smaller than the preset power is judged, and if the power to be output is smaller than the preset power, the upper bridge switching tube and the lower bridge switching tube of the first conversion branch, the second conversion branch and the third conversion branch are controlled according to the power interval where the power to be output is located, so that the first conversion branch, the second conversion branch and the third conversion branch work in turn.
Therefore, the control method of the bidirectional DC-DC converter provided by the embodiment of the invention can realize that the first conversion branch, the second conversion branch and the third conversion branch are controlled to work in turn when the output power is smaller than the preset power, thereby effectively reducing the working time of the switching tube, prolonging the working life of the switching tube in the conversion branch and further prolonging the life cycle of the bidirectional DC-DC converter.
According to an embodiment of the present invention, the plurality of power intervals are a first power interval, a second power interval and a third power interval, the power corresponding to the second power interval is greater than the power corresponding to the first power interval, the power corresponding to the third power interval is greater than the power corresponding to the second power interval, and an upper limit value of the second power interval is a preset power.
That is to say, the power to be output is obtained and the power interval in which the power to be output is located is judged, and if the power interval in which the power to be output is located is the first power interval or the second power interval, the first conversion branch, the second conversion branch and the third conversion branch are controlled to work in turn. The preset power may be 200kw, specifically, the first power interval may be 0kw-100kw, the second power interval may be 100kw-200kw, and the third power interval may be 200kw-300 kw.
According to one embodiment of the invention, when the power to be output is in the first power interval, the upper bridge switching tube and the lower bridge switching tube are controlled, so that the first conversion branch, the second conversion branch and the third conversion branch work in turn.
That is to say, when the power to be output is in the first power interval, the first conversion branch, the second conversion branch and the third conversion branch can work in turn by controlling the upper bridge switching tube and the lower bridge switching tube. For example, when the first conversion branch circuit works, the first upper bridge switching tube and the first lower bridge switching tube of the first conversion branch circuit can be controlled to be switched on or switched off, to control the first conversion branch to work, and at the same time, to control the upper bridge switch tube and the lower bridge switch tube of the second conversion branch and the third conversion branch to be both switched off, when the second conversion branch circuit is controlled to work, the second upper bridge switching tube and the second lower bridge switching tube of the second conversion branch circuit can be controlled to be switched on or switched off, to control the second conversion branch to work, and at the moment, to control the upper bridge switch tube and the lower bridge switch tube of the first conversion branch and the third conversion branch to be both switched off, and when controlling the third conversion branch circuit to work, controlling the third upper bridge switch tube and the third lower bridge switch tube of the third conversion branch circuit to be switched on or switched off, and controlling the third control branch to work, and controlling the upper bridge switching tube and the lower bridge switching tube of the first conversion branch and the second conversion branch to be switched off at the moment. When the upper bridge switching tube and the lower bridge switching tube are controlled to be switched on or switched off, the upper bridge switching tube can be controlled to be switched on or switched off during forward work, and the lower bridge switching tube can be controlled to be switched on or switched off during reverse work.
According to an embodiment of the present invention, the flag bits of the first, second, and third conversion branches are different when operating, wherein when the bidirectional DC-DC converter operates in a manner that the first, second, and third conversion branches sequentially operate in turn each time, the bidirectional DC-DC converter needs to determine the conversion branch that operates first in a cyclic manner of the first conversion branch → the second conversion branch → the third conversion branch → the first conversion branch according to the flag bit of the conversion branch that has finished operating last time when the bidirectional DC-DC converter starts operating currently.
That is, when the bidirectional DC-DC converter operates, the power interval in which the power to be output is determined after the power to be output is obtained, when the power interval in which the power to be output is located is the first power interval, the flag bit of the last conversion branch of the bidirectional DC-DC converter when the operation is ended is obtained, and the conversion branch of the last operation is determined according to the flag bit of the conversion branch when the operation is ended, for example, the conversion flag of the first power interval may be set to flag1, where the flag bit of the first conversion branch is a, the flag bit of the second conversion branch is b, and the flag bit of the third conversion branch is c, that is, when the flag bit of the conversion branch when the operation is ended is obtained, the conversion branch when the operation is ended is determined to be the first conversion branch, and when the flag bit of the conversion branch when the operation is ended is obtained to be b, determining that the conversion branch when the last work is finished is a second conversion branch, and when the flag bit of the conversion branch when the last work is finished is obtained to be c, determining that the conversion branch when the last work is finished is a third conversion branch.
Then, the bidirectional DC-DC converter determines the conversion branch which operates first in a cyclic manner of the first conversion branch → the second conversion branch → the third conversion branch → the first conversion branch based on the flag bit of the conversion branch at the time of last completion of operation, for example, when the conversion branch at the time of last completion of operation is determined to be the first conversion branch, the conversion branch which operates first is determined to be the second conversion branch, when the conversion branch at the time of last completion of operation is determined to be the second conversion branch, the conversion branch which operates first is determined to be the third conversion branch, and when the conversion branch at the time of last completion of operation is determined to be the third conversion branch, the conversion branch which operates first is determined to be the first conversion branch.
When the bidirectional DC-DC converter works in the first power interval for the first time, the conversion branch which works for the first time is the first conversion branch, and then when the bidirectional DC-DC converter works in the first power interval for each time, the bidirectional DC-DC converter works in a circulating mode of the first conversion branch → the second conversion branch → the third conversion branch → the first conversion branch.
According to an embodiment of the invention, when the power to be output is in the second power interval, the upper bridge switching tube and the lower bridge switching tube are controlled, so that two of the first conversion branch, the second conversion branch and the third conversion branch are sequentially in group to work in turn.
It should be noted that the first conversion branch and the second conversion branch may form a first conversion branch group, the first conversion branch and the third conversion branch may form a second conversion branch group, and the second conversion branch and the third conversion branch may form a third conversion branch group. When the power to be output is in the second power interval, the upper bridge switching tube and the lower bridge switching tube of the conversion branch group are controlled, two of the first conversion branch, the second conversion branch and the third conversion branch can be sequentially in a group to work in turn, for example, when the first conversion branch group works, the first upper bridge switching tube and the lower bridge switching tube of the first conversion branch and the second upper bridge switching tube and the second lower bridge switching tube of the second conversion branch can be controlled to be switched on or off, so that the first conversion branch and the second conversion branch are controlled to work, and the upper bridge switching tube and the lower bridge switching tube of the third conversion branch are controlled to be switched off at the moment; when the second conversion branch group works, the first upper bridge switching tube and the first lower bridge switching tube of the first conversion branch and the third upper bridge switching tube and the third lower bridge switching tube of the third conversion branch can be controlled to be switched on or switched off to control the first conversion branch and the third conversion branch to work, and at the moment, the upper bridge switching tube and the lower bridge switching tube of the second conversion branch are controlled to be switched off; when the third conversion branch group works, the second upper bridge switching tube and the second lower bridge switching tube of the second conversion branch and the third upper bridge switching tube and the third lower bridge switching tube of the third conversion branch can be controlled to be switched on or switched off to control the second conversion branch and the third conversion branch to work, and at the moment, the upper bridge switching tube and the lower bridge switching tube of the first conversion branch are controlled to be switched off. When the upper bridge switching tube and the lower bridge switching tube are controlled to be switched on or switched off, the upper bridge switching tube can be controlled to be switched on or switched off during forward work, and the lower bridge switching tube can be controlled to be switched on or switched off during reverse work.
According to an embodiment of the present invention, when the bidirectional DC-DC converter works in a manner that two of the first, second, and third transformation branches are sequentially turned into one group each time, the first transformation branch, the second transformation branch, and the third transformation branch are sequentially turned into one group each time, the first transformation branch, the second transformation branch, the third transformation branch, and the third transformation branch are sequentially turned into one group each time, and the first transformation branch group, which works first, needs to be determined according to the cycle manner of the first transformation branch, the second transformation branch, the first transformation branch, the third transformation branch, the second transformation branch, the third transformation branch, the first transformation branch, and the second transformation branch when the bidirectional DC-DC converter starts to work at present.
That is, when the bidirectional DC-DC converter operates, the power interval in which the power to be output is determined after the power to be output is obtained, when the power interval in which the power to be output is located is the second power interval, the flag bits of the group of conversion branches of the bidirectional DC-DC converter when the operation is last ended are obtained, and the group of conversion branches of the last operation is determined according to the flag bits of the group of conversion branches when the operation is last ended, for example, the conversion flag of the second power interval may be set to flag2, where the flag bit of the first conversion branch group is a ', the flag bit of the second conversion branch group is b', the flag bit of the third conversion branch group is c ', that is, when the flag bit of the group of conversion branches when the operation is last ended is obtained as a', the group of conversion branches when the operation is last ended are determined to be the first conversion branch group, that is, the first conversion branch and the second conversion branch, when the flag bit of the group of conversion branches obtained when the last work is finished is b ', the group of conversion branches obtained when the last work is finished is determined to be a second conversion branch group, namely a first conversion branch and a third conversion branch, and when the flag bit of the group of conversion branches obtained when the last work is finished is c', the group of conversion branches obtained when the last work is finished is determined to be a third conversion branch group, namely a second conversion branch and a third conversion branch.
Then, the bidirectional DC-DC converter determines the conversion branch group which operates first in a cyclic manner of the first conversion branch and the second conversion branch → the first conversion branch and the third conversion branch → the second conversion branch and the third conversion branch → the first conversion branch and the second conversion branch according to the flag bits of the conversion branch group at the time of last completion of operation, for example, when the conversion branch group at the time of last completion of operation is determined to be the first conversion branch group (i.e., the first conversion branch and the second conversion branch), the conversion branch which operates first is determined to be the second conversion branch group (i.e., the first conversion branch and the third conversion branch), when the conversion branch group at the time of last completion of operation is determined to be the second conversion branch group (i.e., the first conversion branch and the third conversion branch), the conversion branch which operates first is determined to be the third conversion branch group (the second conversion branch and the third conversion branch), when the group of conversion branches at the last time of finishing work is determined to be the third conversion branch group (namely, the second conversion branch and the third conversion branch), the conversion branch which is currently started to work is determined to be the first conversion branch group (namely, the first conversion branch and the second conversion branch).
When the bidirectional DC-DC converter works in the second power interval for the first time, the conversion branch which works for the first time is a first conversion branch and a second conversion branch, and then the bidirectional DC-DC converter works in a circulating mode of the first conversion branch and the second conversion branch → the first conversion branch and the third conversion branch → the second conversion branch and the third conversion branch → the first conversion branch and the second conversion branch each time. Specifically, each set of conversion branches equally divides the power to be output when in operation.
According to one embodiment of the invention, when the power to be output is in the third power interval, the upper bridge switching tube and the lower bridge switching tube are controlled, so that the first conversion branch, the second conversion branch and the third conversion branch work simultaneously.
That is to say, when the power to be output is greater than the preset power, the first conversion branch, the second conversion branch and the third conversion branch of the bidirectional DC-DC conversion branch work simultaneously, wherein the first conversion branch, the second conversion branch and the third conversion branch equally divide the power to be output.
Specifically, when the power to be output is in a third power interval, the upper bridge switching tube and the lower bridge switching tube of the first conversion branch, the second conversion branch and the third conversion branch can be controlled to be switched on or switched off simultaneously, so that the first conversion branch, the second conversion branch and the third conversion branch work simultaneously. For example, the first upper bridge switching tube of the first conversion branch, the second upper bridge switching tube of the second conversion branch and the third upper bridge switching tube of the third conversion branch can be controlled to be switched on or switched off when the DC-DC converter works in the forward direction, and the first lower bridge switching tube of the first conversion branch, the second lower bridge switching tube of the second conversion branch and the lower bridge switching tube of the third conversion branch can be controlled to be switched on or switched off when the DC-DC converter works in the reverse direction.
According to an embodiment of the present invention, as shown in fig. 3, the control method of the bidirectional DC-DC converter includes the following steps:
s101: when the bidirectional DC-DC converter is started to work.
S102: and acquiring the power to be output of the bidirectional DC-DC converter.
S103: and judging the power interval where the power to be output is located.
If the power interval in which the power to be output is located is the first power interval, executing step S104;
if the power interval in which the power to be output is located is the second power interval, executing step S106;
if the power interval in which the power to be output is located is the third power interval, step S108 is executed.
S104: and acquiring the zone bit of the conversion branch when the last work is finished.
S105: the conversion leg which is currently working first is determined and step S109 is performed.
S106: and acquiring the zone bits of the group of conversion branches when the work is finished last time.
S107: the set of conversion legs currently working first is determined and step S109 is performed.
S108: and determining that the first transformation branch, the second transformation branch and the third transformation branch work simultaneously.
S109: and controlling the upper bridge switching tube and the lower bridge switching tube according to the determined conversion branch so as to enable the bidirectional DC-DC converter to work.
In summary, the power to be output of the bidirectional DC-DC converter is obtained, the power interval in which the power to be output is located is determined, and the upper switching tube and the lower switching tube are controlled according to the power interval in which the power to be output is located, so that the first conversion branch, the second conversion branch and the third conversion branch are controlled to work in turn when the power to be output is smaller than the preset power, thereby effectively reducing the working time of the switching tubes, prolonging the working life of the switching tubes in the conversion branches, and further prolonging the life cycle of the bidirectional DC-DC converter.
Embodiments of the present invention also provide a non-transitory computer-readable storage medium on which a computer program is stored, the program, when executed by a processor, implementing a method of controlling a bidirectional DC-DC converter.
According to the non-transitory computer readable storage medium of the embodiment of the invention, by implementing the control method of the bidirectional DC-DC converter, the first conversion branch, the second conversion branch and the third conversion branch can be controlled to work in turn when the output power is smaller than the preset power, so that the working time of the switching tube is effectively reduced, the working life of the switching tube in the conversion branch is prolonged, and the life cycle of the bidirectional DC-DC converter can be further prolonged.
The embodiment of the invention also provides a bidirectional DC-DC converter, which comprises a first conversion branch, a second conversion branch and a third conversion branch, wherein the first conversion branch, the second conversion branch and the third conversion branch are connected in parallel, each of the first conversion branch, the second conversion branch and the third conversion branch comprises an upper bridge switching tube and a lower bridge switching tube, the bidirectional DC-DC converter further comprises a memory, a processor and a control program of the bidirectional DC-DC converter, the control program of the bidirectional DC-DC converter is stored on the memory and can be operated on the processor, and when being executed by the processor, the control program of the bidirectional DC-DC converter realizes the control method of the bidirectional DC-DC converter.
According to the bidirectional DC-DC converter provided by the embodiment of the invention, the first conversion branch, the second conversion branch and the third conversion branch can be controlled to work in turn when the power to be output is smaller than the preset power by realizing the control method of the bidirectional DC-DC converter, so that the working time of a switching tube is effectively reduced, the working life of the switching tube in the conversion branch is prolonged, and the life cycle of the bidirectional DC-DC converter can be further prolonged.
Fig. 4 is a block schematic diagram of a control apparatus of a bidirectional DC-DC converter according to an embodiment of the present invention. The bidirectional DC-DC converter comprises a first conversion branch, a second conversion branch and a third conversion branch, wherein the first conversion branch, the second conversion branch and the third conversion branch are connected in parallel, and each conversion branch comprises an upper bridge switching tube and a lower bridge switching tube.
As shown in fig. 4, the control device of the bidirectional DC-DC converter according to the embodiment of the present invention includes: the device comprises an acquisition module 10, a judgment module 20 and a control module 30.
The obtaining module 10 is configured to obtain power to be output of the bidirectional DC-DC converter; the judging module 20 is configured to judge a power interval in which power to be output is located, where the output power of the bidirectional DC-DC converter is divided into a plurality of power intervals; the control module 30 is configured to control the upper bridge switching tube and the lower bridge switching tube according to a power interval where the power to be output is located, so as to control the first conversion branch, the second conversion branch and the third conversion branch to work in turn when the power to be output is smaller than a preset power.
The Control module 30 may be an MCU (Micro Control Unit).
Therefore, the control device of the bidirectional DC-DC converter provided by the embodiment of the invention can control the first conversion branch, the second conversion branch and the third conversion branch to work in turn when the output power is smaller than the preset power, thereby effectively reducing the working time of the switching tube, prolonging the working life of the switching tube in the conversion branch and further prolonging the life cycle of the bidirectional DC-DC converter.
According to an embodiment of the present invention, the plurality of power intervals are a first power interval, a second power interval and a third power interval, the power corresponding to the second power interval is greater than the power corresponding to the first power interval, the power corresponding to the third power interval is greater than the power corresponding to the second power interval, and an upper limit value of the second power interval is a preset power.
That is to say, the determining module 20 obtains the power to be output and determines the power interval in which the power to be output is located, and if the power interval in which the power to be output is located is the first power interval or the second power interval, the control module 30 controls the first converting branch, the second converting branch and the third converting branch to work in turn. The preset power may be 200kw, specifically, the first power interval may be 0kw-100kw, the second power interval may be 100kw-200kw, and the third power interval may be 200kw-300 kw.
According to an embodiment of the present invention, the control module 30 is further configured to control the upper bridge switching tube and the lower bridge switching tube when the power to be output is in the first power interval, so that the first conversion branch, the second conversion branch, and the third conversion branch sequentially work in turn.
That is to say, when waiting output power and being in first power interval, the accessible is controlled upper bridge switch tube and lower bridge switch tube, can make first transform branch road, second transform branch road and third transform the branch road and carry out work in turn in proper order. For example, when the first conversion branch circuit works, the first upper bridge switching tube and the first lower bridge switching tube of the first conversion branch circuit can be controlled to be switched on or switched off, to control the first conversion branch to work, and at the same time, to control the upper bridge switch tube and the lower bridge switch tube of the second conversion branch and the third conversion branch to be both switched off, when the second conversion branch circuit is controlled to work, the second upper bridge switching tube and the second lower bridge switching tube of the second conversion branch circuit can be controlled to be switched on or switched off, to control the second conversion branch to work, and at the moment, to control the upper bridge switch tube and the lower bridge switch tube of the first conversion branch and the third conversion branch to be both switched off, and when controlling the third conversion branch circuit to work, controlling the third upper bridge switch tube and the third lower bridge switch tube of the third conversion branch circuit to be switched on or switched off, and controlling the third control branch to work, and controlling the upper bridge switching tube and the lower bridge switching tube of the first conversion branch and the second conversion branch to be switched off at the moment. When the upper bridge switching tube and the lower bridge switching tube are controlled to be switched on or switched off, the upper bridge switching tube can be controlled to be switched on or switched off during forward work, and the lower bridge switching tube can be controlled to be switched on or switched off during reverse work.
According to an embodiment of the present invention, the flag bits of the first, second, and third conversion branches are different when operating, wherein when the bidirectional DC-DC converter operates in a manner that the first, second, and third conversion branches sequentially operate in turn each time, the control module 30 is further configured to determine, when the bidirectional DC-DC converter currently starts operating, a conversion branch that operates first in a cyclic manner of the first conversion branch → the second conversion branch → the third conversion branch → the first conversion branch according to the flag bit of the conversion branch that has finished operating last time.
That is, when the bidirectional DC-DC converter operates, and the obtaining module 10 obtains the power to be output, the determining module 20 determines the power interval in which the power to be output is located, and when the power interval in which the power to be output is located is the first power interval, the control module 30 obtains the flag bit of the last conversion branch of the bidirectional DC-DC converter when the operation is ended, and determines the last conversion branch according to the flag bit of the last conversion branch when the operation is ended, for example, the conversion flag of the first power interval may be set to flag1, where the flag bit of the first conversion branch is a, the flag bit of the second conversion branch is b, and the flag bit of the third conversion branch is c, that is, when the flag bit of the last conversion branch when the operation is ended is a, the conversion branch when the last operation is determined to be the first conversion branch, and when the flag bit of the last conversion branch when the operation is ended is b, determining that the conversion branch when the last work is finished is a second conversion branch, and when the flag bit of the conversion branch when the last work is finished is obtained to be c, determining that the conversion branch when the last work is finished is a third conversion branch.
Then, the control module 30 determines the conversion branch which operates first in a cyclic manner of the first conversion branch → the second conversion branch → the third conversion branch → the first conversion branch according to the flag bit of the conversion branch which has finished operating last time, for example, when the conversion branch which has finished operating last time is determined to be the first conversion branch, the conversion branch which has started operating currently is determined to be the second conversion branch, when the conversion branch which has finished operating last time is determined to be the second conversion branch, the conversion branch which has started operating currently is determined to be the third conversion branch, and when the conversion branch which has finished operating last time is determined to be the third conversion branch, the conversion branch which has started operating currently is determined to be the first conversion branch.
When the bidirectional DC-DC converter works in the first power interval for the first time, the conversion branch which works for the first time is the first conversion branch, and then when the bidirectional DC-DC converter works in the first power interval for each time, the bidirectional DC-DC converter works in a circulating mode of the first conversion branch → the second conversion branch → the third conversion branch → the first conversion branch.
According to an embodiment of the present invention, the control module 30 is further configured to control the upper bridge switching tube and the lower bridge switching tube when the power to be output is in the second power interval, so that two of the first conversion branch, the second conversion branch and the third conversion branch are a group and work in turn.
It should be noted that the first conversion branch and the second conversion branch may form a first conversion branch group, the first conversion branch and the third conversion branch may form a second conversion branch group, and the second conversion branch and the third conversion branch may form a third conversion branch group. When the power to be output is in the second power interval, the upper bridge switching tube and the lower bridge switching tube of the conversion branch group are controlled, two of the first conversion branch, the second conversion branch and the third conversion branch can be sequentially in a group to work in turn, for example, when the first conversion branch group works, the first upper bridge switching tube and the lower bridge switching tube of the first conversion branch and the second upper bridge switching tube and the second lower bridge switching tube of the second conversion branch can be controlled to be switched on or off, so that the first conversion branch and the second conversion branch are controlled to work, and the upper bridge switching tube and the lower bridge switching tube of the third conversion branch are controlled to be switched off at the moment; when the second conversion branch group works, the first upper bridge switching tube and the first lower bridge switching tube of the first conversion branch and the third upper bridge switching tube and the third lower bridge switching tube of the third conversion branch can be controlled to be switched on or switched off to control the first conversion branch and the third conversion branch to work, and at the moment, the upper bridge switching tube and the lower bridge switching tube of the second conversion branch are controlled to be switched off; when the third conversion branch group works, the second upper bridge switching tube and the second lower bridge switching tube of the second conversion branch and the third upper bridge switching tube and the third lower bridge switching tube of the third conversion branch can be controlled to be switched on or switched off to control the second conversion branch and the third conversion branch to work, and at the moment, the upper bridge switching tube and the lower bridge switching tube of the first conversion branch are controlled to be switched off. When the upper bridge switching tube and the lower bridge switching tube are controlled to be switched on or switched off, the upper bridge switching tube can be controlled to be switched on or switched off during forward work, and the lower bridge switching tube can be controlled to be switched on or switched off during reverse work.
According to an embodiment of the present invention, the flag bits of the first, second, and third transformation branches in pairs are different when the first, second, and third transformation branches sequentially operate in turns, wherein, when the bidirectional DC-DC converter operates in a manner that the first, second, and third transformation branches in pairs sequentially operate in turns each time, the control module 30 is further configured to determine the transformation branch group which operates first in a cyclic manner of the first, second, and third transformation branches → the second and third transformation branches → the first and second transformation branches, according to the flag bits of the last transformation branch when the bidirectional DC-DC converter finishes operating currently.
That is, when the bidirectional DC-DC converter operates, after the obtaining module 10 obtains the power to be output, the determining module 20 determines the power interval in which the power to be output is located, and when the power interval in which the power to be output is located is the second power interval, obtains the flag bits of the group of converting branches of the bidirectional DC-DC converter that has finished operating last time, and determines the group of converting branches of the bidirectional DC-DC converter that has finished operating last time according to the flag bits of the group of converting branches that have finished operating last time, for example, the converting flag of the second power interval may be set to flag2, where the flag bit of the first converting branch group is a ', the flag bit of the second converting branch group is b', the flag bit of the third converting branch group is c ', that is, when the flag bit of the group of converting branches that has finished operating last time is a', the group of converting branches that has finished operating last time is determined to be the first converting branch group, that is the first converting branch and the second converting branch, when the flag bit of the group of conversion branches obtained when the last work is finished is b ', the group of conversion branches obtained when the last work is finished is determined to be a second conversion branch group, namely a first conversion branch and a third conversion branch, and when the flag bit of the group of conversion branches obtained when the last work is finished is c', the group of conversion branches obtained when the last work is finished is determined to be a third conversion branch group, namely a second conversion branch and a third conversion branch.
Then, the bidirectional DC-DC converter determines the conversion branch group which operates first in a cyclic manner of the first conversion branch and the second conversion branch → the first conversion branch and the third conversion branch → the second conversion branch and the third conversion branch → the first conversion branch and the second conversion branch according to the flag bits of the conversion branch group at the time of last completion of operation, for example, when the conversion branch group at the time of last completion of operation is determined to be the first conversion branch group (i.e., the first conversion branch and the second conversion branch), the conversion branch which operates first is determined to be the second conversion branch group (i.e., the first conversion branch and the third conversion branch), when the conversion branch group at the time of last completion of operation is determined to be the second conversion branch group (i.e., the first conversion branch and the third conversion branch), the conversion branch which operates first is determined to be the third conversion branch group (the second conversion branch and the third conversion branch), when the group of conversion branches at the last time of finishing work is determined to be the third conversion branch group (namely, the second conversion branch and the third conversion branch), the conversion branch which is currently started to work is determined to be the first conversion branch group (namely, the first conversion branch and the second conversion branch).
When the bidirectional DC-DC converter works in the second power interval for the first time, the conversion branch which works for the first time is a first conversion branch and a second conversion branch, and then the bidirectional DC-DC converter works in a circulating mode of the first conversion branch and the second conversion branch → the first conversion branch and the third conversion branch → the second conversion branch and the third conversion branch → the first conversion branch and the second conversion branch each time. Specifically, each set of conversion branches equally divides the power to be output when in operation.
According to an embodiment of the present invention, the control module 30 is further configured to control the upper bridge switching tube and the lower bridge switching tube when the power to be output is in the third power interval, so that the first conversion branch, the second conversion branch, and the third conversion branch operate simultaneously.
That is, when the output power is greater than the preset power, the control module 30 controls the first converting branch, the second converting branch and the third converting branch of the bidirectional DC-DC converting branch to operate simultaneously.
Specifically, when the power to be output is in a third power interval, the upper bridge switching tube and the lower bridge switching tube of the first conversion branch, the second conversion branch and the third conversion branch can be controlled to be switched on or switched off simultaneously, so that the first conversion branch, the second conversion branch and the third conversion branch work simultaneously. For example, the first upper bridge switching tube of the first conversion branch, the second upper bridge switching tube of the second conversion branch and the third upper bridge switching tube of the third conversion branch can be controlled to be switched on or switched off when the DC-DC converter works in the forward direction, and the first lower bridge switching tube of the first conversion branch, the second lower bridge switching tube of the second conversion branch and the lower bridge switching tube of the third conversion branch can be controlled to be switched on or switched off when the DC-DC converter works in the reverse direction.
In summary, according to the control device of the bidirectional DC-DC converter in the embodiment of the present invention, the to-be-output power of the bidirectional DC-DC converter is obtained by the obtaining module, and then the power interval where the to-be-output power is located is judged by the judging module, and the control module controls the upper bridge switching tube and the lower bridge switching tube according to the power interval where the to-be-output power is located, so as to control the first converting branch, the second converting branch, and the third converting branch to work in turn when the to-be-output power is smaller than the preset power, thereby effectively reducing the working time of the switching tubes, improving the working life of the switching tubes in the converting branches, and further prolonging the life cycle of the bidirectional DC-DC converter.
The embodiment of the invention also provides a bidirectional DC-DC converter.
Fig. 5 is a block schematic diagram of a bidirectional DC-DC converter according to an embodiment of the invention. As shown in fig. 5, the bidirectional DC-DC converter 200 according to the embodiment of the present invention includes the control device 100 of the bidirectional DC-DC converter.
According to the bidirectional DC-DC converter provided by the embodiment of the invention, the first conversion branch, the second conversion branch and the third conversion branch can be controlled to work in turn when the output power is smaller than the preset power through the control device of the bidirectional DC-DC converter, so that the working time of a switching tube is effectively reduced, the working life of the switching tube in the conversion branch is prolonged, and the life cycle of the bidirectional DC-DC converter can be further prolonged.
The embodiment of the invention also provides a train.
Fig. 6 is a block schematic diagram of a train according to an embodiment of the invention. As shown in fig. 6, the train 300 of the embodiment of the present invention includes a bidirectional DC-DC converter 200.
According to the train provided by the embodiment of the invention, the bidirectional DC-DC converter is utilized, and the first conversion branch, the second conversion branch and the third conversion branch can be controlled to work in turn when the output power is smaller than the preset power, so that the working time of a switching tube is effectively reduced, the working life of the switching tube in the conversion branch is prolonged, and the life cycle of the bidirectional DC-DC converter can be further prolonged.
In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the invention.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.
In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.
In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.
Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.