Disclosure of Invention
Aiming at the defects in the prior art, the feedback system for the regenerative braking energy of the urban rail transit train is provided, wherein the feedback system can monitor the monomer voltage in the energy storage module in real time and balance the monomer voltage in the energy storage module.
The technical scheme adopted by the invention for solving the technical problems is as follows:
a regenerative braking energy feedback system for an urban rail transit train comprises:
the energy storage module is used for storing electric energy generated by braking of the urban rail transit train; the energy storage module comprises a plurality of energy storage modules which are connected in series; the energy storage module comprises a plurality of monomer groups, the monomer groups are connected in series, and each monomer group comprises a plurality of monomers connected in parallel;
the ventilation cooling module is used for air-cooling the energy storage module;
the balance plates are used for acquiring temperature data and voltage data of each energy storage module; the voltage data is the real-time voltage of each monomer in the energy storage module; each balancing plate balances the voltage of each monomer in the energy storage module according to the real-time voltage of each monomer in the energy storage module corresponding to the balancing plate;
the contactor is used for cutting off a circuit in the energy storage module when the temperature of the energy storage module reaches a first temperature preset value or the voltage reaches a first voltage preset value;
the control management module is used for controlling the starting and stopping of the ventilation cooling module and the on-off of the contactor according to the collected temperature data, and is also used for controlling the balance of the monomer voltage in each energy storage module and the on-off of the contactor according to the collected voltage data;
and the self-powered module is used for converting the voltage in each energy storage module and respectively providing a working power supply for each equalizing plate.
Preferably, each parallel node of the single bodies in the energy storage module in parallel is provided with a voltage detection point, and the balancing board collects the voltage of each parallel node to obtain the voltage of each single body group in the energy storage module.
Preferably, the control management module obtains a maximum voltage difference between each single group in the energy storage module according to the voltage on each parallel node collected by the balancing board, and if the maximum voltage difference is higher than a first preset threshold, the control management module starts a balancing circuit in the balancing board to transfer the electric quantity in the single group with the highest voltage value in the energy storage module to the single group with the lowest voltage value in the energy storage module until the maximum voltage difference is lower than the first preset threshold.
Preferably, a balancing resistor is arranged in the cell group, and the balancing resistor is used for discharging to consume energy of the cell group with a higher voltage in the module until a voltage difference between the cell group with the highest voltage and the cell group with the lowest voltage in the energy storage module is smaller than a second preset threshold.
Preferably, said self-powered module comprises:
a first switch (S1), one end of the first switch is connected with the positive output end of the super capacitor bank, and the other end of the first switch is connected with a first thermistor (RTA 1); the other end of the first thermistor is simultaneously connected with a twentieth resistor (R20), a first transient suppression diode (D1) and a twenty-first capacitor (C21), and the other ends of the twentieth resistor, the first transient suppression diode and the twenty-first capacitor are connected with the negative electrode output end of the super capacitor group in parallel;
the first inductor (L1) comprises first to fourth pins, and the first pin of the first inductor is connected with the negative output end of the super capacitor bank; the second pin of the first inductor is connected with the first fuse through the first thermistor; the third pin of the first inductor is simultaneously connected with one ends of twenty-second to twenty-fourth capacitors (C22-C24), and the other ends of the twenty-second to twenty-fourth capacitors are connected with the fourth pin of the first inductor in parallel; a fourth pin of the first inductor is grounded;
a ninth power chip (U9) including first to third pins, the first pin of the ninth power chip being connected to the third pin of the first inductor; the second pin of the ninth power supply chip is simultaneously connected with the fourth pin of the first inductor and one end of a twenty-second resistor (R22); a third pin of the ninth power supply chip is connected with one end of a twenty-first resistor (R21);
the other ends of the twenty-first resistor and the twenty-second resistor are connected with the anode of a second diode (D2) in parallel, and the cathode of the second diode is simultaneously connected with one end of a twenty-third resistor (R23) and the base electrode of the first triode; the other end of the twenty-third resistor and the emitting electrode of the first triode are connected in parallel with a fourth pin of the first inductor; the collector of the first triode is simultaneously connected with a third pin of a ninth power supply chip and the source of a second transistor (K2) through a twenty-fifth resistor (R25), and the source of the second transistor is also sequentially connected with the drain of the second transistor through a twenty-seventh resistor (R27) and a twenty-sixth capacitor (C26); the grid electrode of the second transistor is simultaneously connected with the cathode of a fourth diode (D4) and one end of a twenty-eighth resistor (R28), and the other ends of the fourth diode and the twenty-eighth resistor are connected with the source electrode of the second transistor in parallel; the drain electrode of the second transistor is used as the output end of the direct-current working power supply of the self-powered module;
the second triode (Q2), the one end of twenty-sixth resistance (R26) and the negative pole of third diode are connected simultaneously to the base of second triode, the collecting electrode of first diode is connected to the positive pole of third diode, the fourth pin of the first inductance of emitter parallel connection of the other end of twenty-sixth resistance and second third pipe, the grid of second transistor is connected to the collecting electrode of second triode.
The equalizing circuit in each equalizing plate comprises a plurality of equalizing units and a collecting unit, the equalizing units correspond to the number of the monomer groups respectively, and the collecting unit equalizes the voltage of each monomer in the energy storage module through the equalizing units;
the acquisition unit includes:
eighth to fourteenth inductors (L8-L14) and forty-eighth to fifty-fourth resistors (R48-R54) connected in series in this order two by two to form first to seventh RL series circuits; the resistance end of the first RL series circuit is connected with a fourteenth pin of the control chip, the resistance end of the second RL series circuit is connected with a sixteenth pin of the control chip, the resistance end of the third RL series circuit is connected with an eighteenth pin of the control chip, the resistance end of the fourth RL series circuit is connected with a twentieth pin of the control chip, the resistance end of the fifth RL series circuit is connected with a twenty-second pin of the control chip, the resistance end of the sixth RL series circuit is connected with a twenty-fourth pin of the control chip, and the resistance end of the seventh RL series circuit is connected with a twenty-sixth pin of the control chip; the inductance end of the first RL series circuit is respectively connected with a second pin, a fourth pin, a sixth pin, an eighth pin, a tenth pin and a twelfth pin of the control chip through a seventy-nine resistor (R79); the inductance end of the seventh RL series circuit is respectively grounded and one end of a seventy-third capacitor (C73) through a fifteenth resistor (R55), and the other end of the seventy-third capacitor is connected with a twenty-sixth pin of the control chip;
a fourteenth pin of the control chip is simultaneously connected with the anode of a seventh diode (D7) and one end of a forty-seventh capacitor, and the cathode of the seventh diode and the other end of the forty-seventh capacitor are connected with a sixteenth pin in parallel; the sixteenth pin is simultaneously connected with the anode of an eighth diode (D8) and one end of a forty-eighth capacitor, and the cathode of the eighth diode and the other end of the forty-eighth capacitor are connected with the eighteenth pin in parallel; the eighteenth pin is simultaneously connected with the anode of a ninth diode (D9) and one end of a forty-ninth capacitor, and the cathode of the ninth diode and the other end of the forty-ninth capacitor are connected with the twentieth pin in parallel; the twentieth pin is simultaneously connected with the anode of a twelfth polar tube (D10) and one end of a fifty-th capacitor, and the cathode of the twelfth polar tube and the other end of the fifty-th capacitor are connected with the twenty-second pin in parallel; the twenty-second pin is simultaneously connected with the anode of an eleventh diode (D11) and one end of a fifty-first capacitor, and the cathode of the eleventh capacitor and the other end of the fifty-first capacitor are connected with a twenty-fourth pin in parallel; the twenty-fourth pin is simultaneously connected with the anode of a twelfth diode (D12) and one end of a fifty-second capacitor, and the cathode of the twelfth diode and the other end of the fifty-second capacitor are connected with a twenty-sixth pin in parallel;
the equalization unit includes:
a first field effect transistor (Q1A), the grid of which is used as a second control signal input end through a ninety-four resistor (R94), and simultaneously connects one end of a ninety-fifth resistor (R95) and the cathode of a first voltage-stabilizing diode (ZA1), and the other end of the ninety-fifth resistor and the anode of the first voltage-stabilizing diode are connected in parallel with the source electrode of the first field effect transistor; the source electrode of the first field effect transistor is used as a second port; the drain of the field effect transistor is sequentially connected with a first equalizing resistor (R1A) and a second equalizing resistor (R2A) as a first port.
Preferably, the energy storage module further comprises a remote monitoring terminal, the remote monitoring terminal monitors the temperature and the voltage of the energy storage module during operation, and when the control management module receives the temperature data and the voltage data collected by the equalizing board, the control management module further sends the temperature data and the voltage data to the remote monitoring terminal.
Preferably, the energy storage module further comprises a human-computer interaction module, the human-computer interaction module is used for displaying temperature data and voltage data of the energy storage module, and when the control management module receives the temperature data and the voltage data collected by the balance board, the control management module further sends the temperature data and the voltage data to the human-computer interaction module.
Preferably, the energy storage device further comprises a fuse connected with the energy storage module.
Preferably, the monomer group is formed by connecting three/four monomers in parallel, and the energy storage module is formed by connecting eight/six monomer groups in series.
The invention discloses a regenerative braking energy feedback system for an urban rail transit train, which at least has the following beneficial effects compared with the prior art:
1. the voltage states of the single bodies, the energy storage modules and the feedback system in the regenerative braking energy feedback system of the urban rail transit train can be monitored in real time and can also be monitored remotely.
2. The energy storage module can balance the voltage of each monomer in the energy storage module in energy storage and non-energy storage states, and the maximum voltage difference between the monomers in the energy storage module is ensured to be within a preset range.
3. The disconnection of a single monomer in the regenerative braking energy feedback system of the urban rail transit train does not influence the operation of the whole feedback system.
4. The voltage among the single bodies in the energy storage module can be actively or passively balanced, so that the maximum voltage difference in the energy storage module is within a preset range, and the operation stability of the feedback system is ensured.
5. The energy storage module can be air-cooled through the ventilation cooling fan, and the service life of the feedback system is prolonged.
Detailed Description
The following are specific embodiments of the present invention and are further described with reference to the drawings, but the present invention is not limited to these embodiments.
Referring to fig. 1-6, the present invention discloses a regenerative braking energy feedback system for an urban rail transit train, which includes an energy storage module 1, a ventilation and cooling module 2, a plurality of equalization plates, a contactor, a self-powered module 3, and a control and management module 4. The feedback system can recover energy generated by braking of the urban rail transit train; but running state among the real time monitoring energy storage module 1 specifically can real time monitoring energy storage module 1's real-time condition, like the real-time voltage and the real-time temperature of monitoring energy storage module 8, steerable start-stop of ventilation cooling module 2 controls the real-time temperature of energy storage module 1, is provided with the contactor simultaneously, and when the temperature among the energy storage module 8 is too high or the voltage is too high, the steerable contactor of control management module 4 cuts off the circuit of energy storage module 8 in order to protect whole feedback system, self-power module is arranged in converting the voltage among the energy storage module, for a plurality of the equalizer plate provides working power.
In this embodiment, the energy storage module 1 is configured to store electric energy generated by braking of the urban rail transit train, and convert braking energy of the urban rail transit train into electric energy to be stored in the energy storage module 1.
In order to ensure that the energy storage module 1 can stably operate, the control management module 4 controls the start and stop of the ventilation cooling module 2 and the on-off of the contactor according to the acquired temperature data, and the temperature in the energy storage module 1 is ensured to be within the safe operation range.
The control management module 4 can control the balance of the voltage in the energy storage module 1 according to the acquired voltage data, so that the energy storage module 8 is in a stable running state when storing electric energy.
The self-powered module 3 is specifically connected in a manner that includes:
a first switch (S1), one end of the first switch is connected with the positive output end of the super capacitor bank, the other end of the first switch is connected with a first fuse (FA1), and the other end of the first fuse is connected with a first thermistor (RTA 1); the other end of the first thermistor is simultaneously connected with a twentieth resistor (R20), a first transient suppression diode (D1) and a twenty-first capacitor (C21), and the other ends of the twentieth resistor, the first transient suppression diode and the twenty-first capacitor are connected with the negative electrode output end of the super capacitor group in parallel;
the first inductor (L1) comprises first to fourth pins, and the first pin of the first inductor is connected with the negative output end of the super capacitor bank; the second pin of the middle first inductor is connected with the first fuse through the first thermistor; the third pin of the first inductor is simultaneously connected with one ends of twenty-second to twenty-fourth capacitors (C22-C24), and the other ends of the twenty-second to twenty-fourth capacitors are connected with the fourth pin of the first inductor in parallel; a fourth pin of the first inductor is grounded;
a ninth power chip (U9) including first to third pins, the first pin of the ninth power chip being connected to the third pin of the first inductor; the second pin of the ninth power supply chip is simultaneously connected with the fourth pin of the first inductor and one end of a twenty-second resistor (R22); a third pin of the ninth power supply chip is connected with one end of a twenty-first resistor (R21);
the other ends of the twenty-first resistor and the twenty-second resistor are connected with the anode of a second diode (D2) in parallel, and the cathode of the second diode is simultaneously connected with one end of a twenty-third resistor (R23) and the base electrode of the first triode; the other end of the twenty-third resistor and the emitting electrode of the first triode are connected in parallel with a fourth pin of the first inductor; the collector of the first triode is simultaneously connected with a third pin of a ninth power supply chip and the source of a second transistor (K2) through a twenty-fifth resistor (R25), and the source of the second transistor is also sequentially connected with the drain of the second transistor through a twenty-seventh resistor (R27) and a twenty-sixth capacitor (C26); the grid electrode of the second transistor is simultaneously connected with the cathode of a fourth diode (D4) and one end of a twenty-eighth resistor (R28), and the other ends of the fourth diode and the twenty-eighth resistor are connected with the source electrode of the second transistor in parallel; the drain electrode of the second transistor is used as the output end of the direct-current working power supply of the self-powered module 3;
a second triode (Q2), the one end of twenty-sixth resistance (R26) and the negative pole of third diode are connected simultaneously to the base of second triode, the collecting electrode of first diode is connected to the positive pole of third diode, the fourth pin of the first inductance of emitter parallel connection of the other end of twenty-sixth resistance and second third pipe, the grid of second transistor is connected to the collecting electrode of second triode.
When the energy storage module inputs a direct-current power supply to the self-powered module 3 and the first switch (S1) is switched on, the current firstly passes through the fuse (FA1) to judge the current flowing through the fuse, when the current exceeding the preset current (the model of the fuse can be selected according to actual requirements) passes through the fuse, the fuse is timely fused to protect the circuit, the damage to components and parts caused by the large current is avoided, and noise waves in the direct current are filtered by utilizing the characteristics of the transient secondary suppression tube and the inductor L1; then, the voltage is reduced by a ninth power chip (U9, the model is K7805-1000R3), 5V output voltage is output, meanwhile, the input voltage is judged by a second transistor (K2, an MOS tube), the output voltage is guaranteed not to exceed a preset safety threshold (5.5V), and the overall safety and reliability of the circuit are guaranteed.
The equalizing circuit in each equalizing plate comprises a plurality of equalizing units and a collecting unit, the equalizing units correspond to the number of the monomer groups respectively, and the collecting unit equalizes the voltage of each monomer in the energy storage module through the equalizing units;
the acquisition unit includes:
the control chip comprises first to forty-eight pins;
eighth to fourteenth inductors (L8-L14) and forty-eighth to fifty-fourth resistors (R48-R54) connected in series in this order two by two to form first to seventh RL series circuits; the resistance end of the first RL series circuit is connected with a fourteenth pin of the control chip, the resistance end of the second RL series circuit is connected with a sixteenth pin of the control chip, the resistance end of the third RL series circuit is connected with an eighteenth pin of the control chip, the resistance end of the fourth RL series circuit is connected with a twentieth pin of the control chip, the resistance end of the fifth RL series circuit is connected with a twenty-second pin of the control chip, the resistance end of the sixth RL series circuit is connected with a twenty-fourth pin of the control chip, and the resistance end of the seventh RL series circuit is connected with a twenty-sixth pin of the control chip; the inductance end of the first RL series circuit is respectively connected with a second pin, a fourth pin, a sixth pin, an eighth pin, a tenth pin and a twelfth pin of the control chip through a seventy-nine resistor (R79); the inductance end of the seventh RL series circuit is respectively grounded and one end of a seventy-third capacitor (C73) through a fifteenth resistor (R55), and the other end of the seventy-third capacitor is connected with a twenty-sixth pin of the control chip;
a fourteenth pin of the control chip is simultaneously connected with the anode of a seventh diode (D7) and one end of a forty-seventh capacitor, and the cathode of the seventh diode and the other end of the forty-seventh capacitor are connected with a sixteenth pin in parallel; the sixteenth pin is simultaneously connected with the anode of an eighth diode (D8) and one end of a forty-eighth capacitor, and the cathode of the eighth diode and the other end of the forty-eighth capacitor are connected with the eighteenth pin in parallel; the eighteenth pin is simultaneously connected with the anode of a ninth diode (D9) and one end of a forty-ninth capacitor, and the cathode of the ninth diode and the other end of the forty-ninth capacitor are connected with the twentieth pin in parallel; the twentieth pin is simultaneously connected with the anode of a twelfth polar tube (D10) and one end of a fifty-th capacitor, and the cathode of the twelfth polar tube and the other end of the fifty-th capacitor are connected with the twenty-second pin in parallel; the twenty-second pin is simultaneously connected with the anode of an eleventh diode (D11) and one end of a fifty-first capacitor, and the cathode of the eleventh capacitor and the other end of the fifty-first capacitor are connected with a twenty-fourth pin in parallel; the twenty-fourth pin is simultaneously connected with the anode of a twelfth diode (D12) and one end of a fifty-second capacitor, and the cathode of the twelfth diode and the other end of the fifty-second capacitor are connected with a twenty-sixth pin in parallel;
the equalization unit includes:
a first field effect transistor (Q1A), the grid of which is used as a second control signal input end through a ninety-four resistor (R94), and simultaneously connects one end of a ninety-fifth resistor (R95) and the cathode of a first voltage-stabilizing diode (ZA1), and the other end of the ninety-fifth resistor and the anode of the first voltage-stabilizing diode are connected in parallel with the source electrode of the first field effect transistor; the source electrode of the first field effect transistor is used as a second port; the drain of the field effect transistor is sequentially connected with a first equalizing resistor (R1A) and a second equalizing resistor (R2A) as a first port.
In the embodiment, each energy storage module is provided with six groups of monomer groups connected in series, each monomer group is connected with four monomers in parallel, and the energy storage module is provided with six groups of monomer groups of forty-seventh to fifty-second capacitors (C47-C52); the control chip (U13, chip type LTC6804-2) comprises first to forty-eighth pins.
In order to carry out potential balance on the monomers in the energy storage module, real-time voltage data of the monomers in the energy storage module are collected through the balance board, the maximum voltage difference among the monomers in the energy storage module is compared, if the maximum voltage difference is larger than a preset value, the balance circuit is started, the electric quantity of the monomer with the highest voltage value in the energy storage module is transferred to the monomer with the highest voltage value in the energy storage module, or the monomer with the highest voltage value is discharged, and the electric energy of the monomer is consumed through the balance resistor.
The feedback system further comprises a remote monitoring terminal 6, the remote monitoring terminal 6 monitors the temperature and the voltage of the energy storage module 1 during operation, and when the control management module 4 receives temperature data and voltage data collected by the plurality of equalizing plates 3, the control management module 4 further sends the temperature data and the voltage data to the remote monitoring terminal 6.
Specifically, the remote monitoring terminal 6 is a display device with a communication function, and may be a mobile phone or a computer.
The feedback system further comprises a human-computer interaction module 5, the human-computer interaction module 5 is used for displaying temperature data and voltage data of the energy storage module 1, and when the control management module 4 receives the temperature data and the voltage data collected by the balance board, the control management module 4 further sends the temperature data and the voltage data to the human-computer interaction module 5.
The human-computer interaction module 5 can specifically display operation parameters in the whole feedback system, the operation parameters comprise temperature data and voltage data of the energy storage module 1, the human-computer interaction module 5 can serve as an input end, and parameters for controlling the specific operation of the feedback system can be input through the human-computer interaction module 5.
The feedback system further comprises a fuse connected with the energy storage module 8, and the fuse can be automatically fused when the feedback system is short-circuited, so that the circuit safety of the feedback system is protected.
In this embodiment, the energy storage module 1 includes a plurality of energy storage modules 8, and the plurality of energy storage modules 8 are connected in series; the energy storage module 8 comprises a plurality of monomer groups 9, the monomer groups 9 are connected in series, and the monomer groups 9 comprise a plurality of monomers connected in parallel.
The monomer group 9 is formed by connecting three monomers in parallel, and the energy storage module 8 is formed by connecting eight monomer groups 9 in series.
The energy storage module 8 adopts a connection mode of first parallel connection and second serial connection, and the working state of the whole energy storage module 8 and even the whole feedback system cannot be influenced by the fact that a single monomer is electrically disconnected in a short time by the energy storage module 8; for example, if a single cell is electrically disconnected, the other two single cells in the single cell group 9 can still work normally.
The single bodies in the energy storage module 8 are connected in a parallel-series connection mode, so that the voltage of each single body in the whole energy storage module 8 is more stable; the three monomers are connected in parallel to form the monomer group 9, the voltages of the monomers in the monomer group 9 are equal, so that the voltage difference between the monomer groups 9 connected in series in the energy storage module 8 is smaller, in order to more clearly express the characteristic that the energy storage module 8 in this embodiment adopts three parallel eight series, compared with the common energy storage module 8 formed by connecting monomers in series, in the actually produced monomers, even if the single bodies with the same model number have different performances, the common energy storage module 8 is formed by connecting the single bodies in series, the differences among the single bodies can be completely displayed during charging and discharging, the performance of the common energy storage module 8 is unstable, in the energy storage module 8, three monomers are connected in parallel to form a monomer group 9, the voltage of the monomer group 9 is the voltage of the monomer, in this way, the voltage difference between the cell groups 9, i.e. between the cells, is weakened.
The energy storage module 8 can discharge electricity and meets the condition that the residual voltage is lower than 36V; the monomer adopted in the embodiment can be discharged to 0V when being discharged.
Each parallel node of the energy storage module 8, in which the monomers are connected in parallel, is provided with a voltage detection point, and the balancing board collects the voltage of each parallel node to obtain the voltage of each monomer group 9 in the energy storage module 8.
The equalizing plates 7 collect real-time voltages of the monomers in the energy storage modules 8 and real-time temperatures of the energy storage modules 8; the balancing plates 7 are also used for balancing the voltage of the single body in each energy storage module 8; in this embodiment, for accurate measurement, more than two paths are generally provided to measure the temperature of each energy storage module 8.
In this embodiment, set up nine check points in the energy storage module 8, detect the voltage of eight monomer groups 9 in the energy storage module 8 through nine check points, the voltage of monomer group 9 also is monomeric voltage, this application sets up nine check points in energy storage module 8, equalizer plate 7 detects the voltage of each monomer group 9 and the voltage of energy storage module 8 through nine in the energy storage module 8, wherein, the voltage of monomer group 9 equals with the monomeric voltage in this monomer group 9, consequently, equalizer plate 7 can detect each monomeric voltage in energy storage module 8 and the energy storage module 8 in real time.
The equalizing board 7 sends the acquired temperature data and voltage data of the energy storage module 8 to the control management module 4, and the control management module 4 sends the temperature data and the voltage data to the human-computer interaction module 5 and the remote monitoring terminal 6.
The contactor is connected with the energy storage module 1, and when the temperature of the single body in the energy storage module 1 is too high and is higher than the first temperature for presetting, the control management module 4 controls the contactor to be disconnected, so that the fault is prevented from being enlarged.
When the equalizing board 7 detects that the voltage of the single body in the energy storage module 8 is too high and is higher than the preset voltage, the control management system controls the contactor to be disconnected; the invention protects the operation of the feedback device by arranging the contactor.
The ventilation cooling module 2 is controlled by the control management module 4 to be started when the temperature in the energy storage module 1 is higher than a second preset temperature, the ventilation cooling module 2 cools the energy storage module 1 through air cooling, so that the operating temperature of the energy storage module 1 is within a preset range, and the first preset temperature value is larger than the second preset temperature value.
In this embodiment, there are two balancing manners of the cell voltage in the energy storage module 8, specifically including an active balancing manner and a passive balancing manner.
Active equalization of cell voltage in the energy storage module 8: the control management module 4 is further configured to control the balancing board 7 to balance voltages of the monomer groups 9 in the energy storage module 8 corresponding to the balancing board 7, the control management module 4 obtains a maximum voltage difference between the monomer groups 9 in the energy storage module 8 according to the voltages at the parallel nodes collected by the balancing board 7, and if the maximum voltage difference is higher than a first preset threshold, the control management module 4 starts a balancing circuit in the balancing board 7 to transfer electric quantity in the monomer group 9 with a higher voltage value in the energy storage module 8 to the monomer group 9 with a lower voltage value in the energy storage module 8 until the maximum voltage difference is lower than the first preset threshold.
Passive equalization of cell voltages in the energy storage module 8: the cell groups 9 are provided with equalizing resistors, the equalizing plate 7 collects voltages of all parallel nodes in the energy storage module 8, maximum voltage differences among the cell groups 9 in the energy storage module 8 are obtained, if the maximum voltage differences are higher than a second preset threshold value, the equalizing resistors are used for discharging to consume energy of the cell groups 9 with higher voltages in the module until the voltage differences between the cell groups 9 with the highest voltages and the cell groups 9 with the lowest voltages in the energy storage module 8 are smaller than the second preset threshold value.
The specific embodiments described herein are merely illustrative of the spirit of the invention. Various modifications or additions may be made to the described embodiments or alternatives may be employed by those skilled in the art without departing from the spirit or ambit of the invention as defined in the appended claims.