Energy storage and discharge system and hydrogen energy bullet train

Abstract

The utility model discloses an energy storage and discharge system and a hydrogen energy bullet train, and relates to the technical field of hydrogen energy bullet trains. The energy storage and discharge system comprises a hydrogen fuel cell, a traction converter, a plurality of power batteries connected in parallel and a traction motor; the traction converter comprises a charging circuit, a discharging circuit and a traction inverter; the hydrogen fuel cell is electrically connected with the traction inverter through a first circuit, one ends of the charging circuit and the discharging circuit are electrically connected with the first circuit, and the other ends are electrically connected with the power cell. According to the energy storage and discharge system provided by the utility model, one-to-one charging or convenience of the batteries connected in parallel can be realized under different working conditions, and the problems that charging and discharging cannot be controlled and mutual charging among the batteries cannot be controlled when the power batteries are used under the condition that the power batteries are connected in parallel are effectively solved.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen-powered motor vehicles, and more specifically, to an energy storage and discharge system. Furthermore, the present invention also relates to a hydrogen-powered motor vehicle comprising the energy storage and discharge system. Background Art

[0002] With rapid economic development, green transportation is becoming increasingly important in urban public transportation systems. Compared to current ground-based catenary-based rail transit, hydrogen-powered rail transit, equipped with its own onboard hydrogen fuel cell system, eliminates its reliance on external traction power supply catenary systems and has promising development and application prospects.

[0003] Currently, the system logic used in hydrogen fuel cell applications is as follows: during traction, the hydrogen fuel cell and power battery jointly drive the train; during braking, regenerative braking reversely charges the power battery. Typically, the hydrogen fuel cell is combined with the power lithium battery via a DC / DC module, and then converted into AC power by a traction inverter to drive the traction motor. However, this method fails to effectively control the charging of the power battery, which can easily lead to overcharging and shorten battery life. Furthermore, when the power batteries are connected in parallel, the problem of mutual charging and discharging between the batteries cannot be resolved.

[0004] In addition, some technical solutions use hybrid power of the power grid and hydrogen fuel cells. The hydrogen fuel cell is connected to the DC bus of the traction inverter through a boost circuit, and the power battery is connected to the bus. However, this method is suitable for a single set of power batteries, and a braking resistor must be set up separately to consume the energy of regenerative braking.

[0005] In summary, how to provide an energy storage and discharge system that can realize one-to-one charging and discharging of parallel batteries is a problem that urgently needs to be solved by those skilled in the art. Utility Model Content

[0006] In view of this, the purpose of the present invention is to provide an energy storage and discharge system, which can realize one-to-one charging and discharging of power batteries connected in parallel by setting a charging circuit and a discharging circuit.

[0007] Another object of the present invention is to provide a hydrogen-powered electric vehicle comprising the above-mentioned energy storage and discharge system.

[0008] In order to achieve the above purpose, the present invention provides the following technical solutions:

[0009] An energy storage and discharge system includes a hydrogen fuel cell, a traction converter, a plurality of power batteries connected in parallel, and a traction motor;

[0010] The traction converter includes a charging circuit, a discharging circuit and a traction inverter; the hydrogen fuel cell and the traction inverter are electrically connected through a first circuit, and one end of the charging circuit and the discharging circuit are electrically connected to the first circuit and the other end are electrically connected to the power battery.

[0011] Optionally, the charging circuit is provided with charging branches corresponding one-to-one to the power batteries, and any of the charging branches is provided with a first control switch.

[0012] Optionally, the discharge circuit is provided with discharge branches corresponding one-to-one to the power batteries, and any of the discharge branches is provided with a second control switch.

[0013] Optionally, any of the charging branches is provided with a first status indicator light for displaying the charging status, and when the charging branch is in the charging state, the first status indicator light is on.

[0014] Optionally, any of the discharge branches is provided with a second status indicator light for displaying a discharge status, and when the discharge branch is in a discharge status, the second status indicator light is on.

[0015] Optionally, the traction converter further includes an auxiliary inverter;

[0016] In the discharge state, one end of the auxiliary inverter is connected to the first circuit, and the other end is used to connect to the electrical equipment;

[0017] In the charging state, one end of the auxiliary inverter is connected to the first circuit, and the other end is used to connect to the power supply device.

[0018] Optionally, a third control switch for controlling whether the auxiliary inverter is connected to the first circuit is provided on the connection circuit between the auxiliary inverter and the first circuit.

[0019] Optionally, the traction converter further includes a transformer, and the transformer is detachably connected to the auxiliary inverter.

[0020] Optionally, there are multiple traction motors, and the multiple traction motors are arranged in parallel. A fourth control switch is provided between any traction motor and the traction inverter.

[0021] A hydrogen-powered electric vehicle comprises the energy storage and discharge system described in any one of the above.

[0022] The utility model provides an energy storage and discharge system, comprising a hydrogen fuel cell, a traction converter, a plurality of power batteries connected in parallel, and a traction motor; the traction converter comprises a charging circuit, a discharging circuit, and a traction inverter; the hydrogen fuel cell and the traction inverter are electrically connected via a first circuit, and one end of each of the charging circuit and the discharging circuit is electrically connected to the first circuit, and the other end is electrically connected to the power battery.

[0023] During actual use, during traction operation, the power battery is connected to the first circuit through the discharge circuit, and the power battery and the hydrogen fuel cell simultaneously supply power to the traction inverter to drive the traction motor; during constant speed operation, the hydrogen fuel cell supplies power to the traction inverter to drive the traction motor; at the same time, the hydrogen fuel cell charges the power battery through the charging circuit; during regenerative braking operation, the traction motor switches to power generation state, the AC power is reverse-rectified into DC power by the traction inverter, and the power battery is charged through the charging circuit. Multiple groups of parallel power batteries control the charging current separately in the charging circuit.

[0024] The beneficial effects of the energy storage and discharge system provided by the utility model include:

[0025] 1. In actual use, under different working conditions, the batteries connected in parallel can be charged one-to-one or conveniently, which effectively solves the problem of uncontrollable charging and discharging and mutual charging between batteries when the power batteries are used in parallel.

[0026] 2. The traction converter provided by the present invention includes a charging circuit, a discharging circuit and a traction inverter. The charging circuit and the discharging circuit are independently arranged, which facilitates the maintenance of the charging circuit and the discharging circuit.

[0027] In addition, the present invention also provides a hydrogen-powered electric vehicle including the above-mentioned energy storage and discharge system. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0029] Figure 1 This is a schematic diagram of the principle of a specific embodiment of the energy storage and discharge system provided by the present invention in a constant speed working condition;

[0030] Figure 2 A schematic diagram of the principle of a specific embodiment of the energy storage and discharge system provided by the present utility model in a traction working condition;

[0031] Figure 3 A schematic diagram of the principle of a specific embodiment of the energy storage and discharge system provided by the present invention in a braking condition;

[0032] Figure 4 This is a schematic diagram of the principle of a specific embodiment of charging the external power supply equipment in the workshop of the energy storage and discharge system provided by the utility model;

[0033] Figure 5 It is a partial structural diagram of the discharge circuit;

[0034] Figure 6 This is a partial structural diagram of the charging circuit.

[0035] Figures 1-6 middle:

[0036] 1 is a hydrogen fuel cell;

[0037] 2 is the traction converter;

[0038] 21 is a charging circuit, 211 is a charging branch circuit;

[0039] 22 is a discharge circuit, 221 is a discharge branch;

[0040] 23 is a traction inverter;

[0041] 24 is an auxiliary inverter;

[0042] 3 is the power battery;

[0043] 4 is the traction motor;

[0044] 5 is a power supply device. DETAILED DESCRIPTION

[0045] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0046] The core of the utility model is to provide an energy storage and discharge system, which can realize one-to-one charging and discharging of power batteries connected in parallel by setting a charging circuit and a discharging circuit.

[0047] Another core of the present invention is to provide a hydrogen-powered electric vehicle including the above-mentioned energy storage and discharge system.

[0048] Please refer to Figures 1 to 6 .

[0049] This specific embodiment provides an energy storage and discharge system, including a hydrogen fuel cell 1, a traction converter 2, several power batteries 3 connected in parallel, and a traction motor 4; the traction converter 2 includes a charging circuit 21, a discharging circuit 22, and a traction inverter 23; the hydrogen fuel cell 1 and the traction inverter 23 are electrically connected through a first circuit, and one end of the charging circuit 21 and the discharging circuit 22 are electrically connected to the first circuit and the other end is electrically connected to the power battery 3.

[0050] It should be noted that the energy storage and discharge system in this specific embodiment can be applied to hydrogen fuel cell 1 vehicles, hydrogen fuel cell 1 ships, hydrogen fuel cell 1 motor vehicles, etc., which is determined according to actual conditions and will not be elaborated here.

[0051] The hydrogen fuel cell 1 in this embodiment is a device that directly converts the chemical energy of hydrogen and oxygen into electrical energy. Its operating principle is based on an electrochemical redox reaction. In a fuel cell, hydrogen undergoes an oxidation reaction at the anode (negative electrode). The hydrogen molecules, under the action of a catalyst (typically a precious metal such as platinum), decompose into hydrogen ions (protons) and electrons.

[0052] Combine Figures 1 to 4 As shown, since the hydrogen fuel cell 1 generates direct current (DC), while the traction motor 4 typically requires AC to drive, the traction inverter 23 primarily functions to convert the DC output of the hydrogen fuel cell 1 into the AC required by the traction motor 4. Therefore, the first circuit between the hydrogen fuel cell 1 and the traction inverter 23 is primarily used to transmit DC power, ensuring a stable power supply to the traction inverter 23, enabling it to perform normal DC-AC conversion.

[0053] The traction inverter 23 and the traction motor 4 may be connected via a second circuit.

[0054] It should be noted that the charging circuit 21 mentioned in this specific embodiment may include a rectifier, a filter, and a transformer. The rectifier's primary function is to convert AC power into DC power, as the power battery 3 typically requires DC power for charging. For example, a common diode bridge rectifier can convert input AC voltage (such as 220V AC for household use) into a pulsating DC voltage. Some high-performance charging circuits 21 utilize more complex controlled rectifiers, such as thyristor rectifiers, which can adjust the output DC voltage as needed to better meet the charging requirements of different types of power batteries 3. The filter's function is to remove or reduce this ripple, as the rectified DC power may contain ripple components. This ripple can adversely affect the charging of the power battery 3, such as causing battery heating and shortening battery life. The filter is used to remove or reduce this ripple, resulting in a smoother output DC voltage. The transformer is primarily used to adjust the input voltage to meet the charging voltage requirements of the power battery 3.

[0055] In addition to the aforementioned structure, the charging circuit 21 provided in this embodiment may also include a power management chip capable of monitoring and controlling the entire charging process. This chip can determine the appropriate charging strategy based on the type of power battery 3 (e.g., lithium-ion battery, nickel-metal hydride battery, etc.), the current battery status (e.g., remaining charge, temperature, etc.), and the performance of the charging device. The charging circuit 21 may also be equipped with a first voltage sensor and a first current sensor for real-time monitoring of the charging voltage and current. The first voltage sensor and the first current sensor feed back the detected signals to the charge management chip. The first voltage sensor accurately measures the voltage across the power battery 3, ensuring that the charging voltage does not exceed the rated voltage of the battery, thereby preventing overcharging and damage to the power battery 3. The first current sensor monitors the charging current, ensuring that the charging current is within the battery's allowable range and calculating the charging progress of the power battery 3 based on the actual current.

[0056] Of course, the charging circuit 21 in this specific embodiment may also include other structural components, which are determined according to actual conditions and will not be described in detail here.

[0057] The discharge circuit 22 provided in this embodiment may include a controller, power electronics, a second current sensor, and a second voltage sensor. The controller's primary function is to control the discharge process based on load demand and battery status. For example, in an electric vehicle, when the driver presses the accelerator pedal, the controller receives a signal and then adjusts the battery's discharge current based on factors such as the remaining battery charge, temperature, and the motor's power requirements. Power electronics may include MOSFETs (metal-oxide-semiconductor field-effect transistors) or IGBTs (insulated-gate bipolar transistors), along with freewheeling diodes. The second current sensor and the second voltage sensor are used to monitor the discharge current and voltage of the power battery 3 in real time. The second current sensor is generally based on the Hall effect principle and can accurately measure the current flowing through it. For example, in an energy storage system using lithium-ion batteries, the second current sensor can provide feedback to the controller regarding the actual discharge current of the battery. The controller uses this information to determine whether the discharge status of the power battery 3 is normal. The second voltage sensor is used to monitor the voltage across the battery to prevent over-discharge of the power battery 3. When the voltage of the power battery 3 drops to a certain level, the controller can take measures, such as reducing the load power or stopping discharge, to protect the power battery 3.

[0058] Of course, the discharge circuit 22 in this specific embodiment may also include other structural components, which are determined according to actual conditions and will not be described in detail here.

[0059] During actual use, the specific conditions of different working conditions are as follows: in traction working condition, the power battery 3 is connected to the first circuit through the discharge circuit 22, and the power battery 3 and the hydrogen fuel cell 1 simultaneously supply power to the traction inverter 23 to drive the traction motor 4 to operate; in constant speed working condition, the hydrogen fuel cell 1 supplies power to the traction inverter 23 to drive the traction motor 4 to operate; at the same time, the hydrogen fuel cell 1 charges the power battery 3 through the charging circuit 21; in regenerative braking working condition, the traction motor 4 switches to the power generation state, the AC power is reverse rectified into DC power through the traction inverter 23, and the power battery 3 is charged through the charging circuit 21, and multiple groups of parallel power batteries 3 control the charging current separately in the charging circuit 21.

[0060] The beneficial effects of the energy storage and discharge system provided by this specific embodiment include:

[0061] 1. In actual use, under different working conditions, the batteries connected in parallel can be charged one-to-one or conveniently, which effectively solves the problem of being unable to control charging and discharging and mutual charging between batteries when the power batteries are used in parallel.

[0062] 2. The traction converter 2 provided by the present invention includes a charging circuit 21 , a discharging circuit 22 and a traction inverter 23 . The charging circuit 21 and the discharging circuit 22 are independently arranged, which facilitates maintenance of the charging circuit 21 and the discharging circuit 22 .

[0063] In a specific embodiment, the charging circuit 21 is provided with charging branches 211 corresponding one to one with the power batteries 3 , and each charging branch 211 is provided with a first control switch.

[0064] During actual use, when the power battery 3 needs to be charged, the first control switch in the charging branch 211 is turned on. When part of the power battery 3 needs to be charged, the corresponding first control switch can be selectively controlled to be turned on to charge the power battery 3 in a targeted manner; when charging is completed, the corresponding first control switch can be controlled to be turned off to avoid overcharging.

[0065] Specifically, to prevent overcharging of the power battery 3 during charging, a first voltage comparator and a reference voltage source can be provided in the charging branch 211, and the charging branch 211 can be connected to the control circuit. In actual use, the first voltage comparator is used to compare the actual charging voltage of the power battery 3 with a preset reference voltage. The reference voltage source provides a stable reference voltage that corresponds to the battery's safe charging limit voltage. When the battery charging voltage exceeds the reference voltage, the first voltage comparator outputs a signal that triggers the control circuit to stop charging. For example, in a simple battery charging protection circuit, the first voltage comparator compares the voltage across the battery with a 4.2V reference voltage. Once the power battery 3 voltage exceeds 4.2V, the comparator outputs a high-level signal, which can be used to shut down the charging circuit 21. The first voltage comparator has high speed and high sensitivity, enabling it to react quickly when the battery voltage reaches the overcharge threshold. The reference voltage source must be highly stable to ensure the accuracy of the reference voltage and to be unaffected by factors such as temperature and power supply fluctuations.

[0066] An overcharge protection circuit can also be provided in the charging branch 211. Within the charging circuit 21, a power device such as a MOSFET (metal-oxide-semiconductor field-effect transistor) is used to implement the overcharge protection circuit. Under normal charging conditions, the MOSFET is on, allowing the charging current to flow. When the voltage of the power battery 3 reaches the overcharge protection voltage, a control signal turns off the MOSFET, thereby cutting off the charging current. For example, if the power battery 3 is detected to be overcharged, the MOSFET in the overcharge protection circuit immediately turns off, preventing further charging of the power battery 3. MOSFETs have the advantages of low on-resistance and high switching speed, enabling rapid shutdown of the charging current when overcharging occurs, minimizing damage to the battery. Furthermore, this protection circuit can be easily integrated with other circuits, enabling precise control of the charging process through simple control signals.

[0067] In the energy storage and discharge system of this specific embodiment, since the charging branch 211 corresponds one-to-one with the power battery 3, during the charging process, the charging of the corresponding power battery 3 can be controlled by the corresponding charging branch 211, and targeted control can be performed on the specific power battery 3, and the control process is convenient.

[0068] On the basis of the above embodiment, a discharge branch 221 corresponding to each power battery 3 may be provided in the discharge circuit 22 , and each discharge branch 221 is provided with a second control switch.

[0069] During actual use, when the power battery 3 needs to be discharged, the second control switch in the discharge branch 221 is turned on. When part of the power battery 3 needs to be discharged, the corresponding second control switch can be selectively controlled to be turned on to discharge the power battery 3 in a targeted manner; when the discharge is completed, the corresponding second control switch can be controlled to be closed to avoid over-discharge.

[0070] Specifically, to prevent over-discharge of the power battery 3 during charging, an undervoltage protection circuit can be provided in the discharge branch 221. This undervoltage protection circuit is primarily implemented using a second voltage comparator, which is connected to the relevant control circuit. In the circuit, the second voltage comparator compares the real-time voltage of the power battery 3 with a preset undervoltage threshold. When the voltage of the power battery 3 drops below this threshold, the second voltage comparator outputs a signal, triggering the control circuit to disconnect the power battery 3 from the load, thereby preventing over-discharge of the power battery 3. In this specific embodiment, in addition to the second voltage comparator, a stable reference voltage source is required to provide a reference voltage for the undervoltage threshold. The stability of this reference voltage source is crucial to the accuracy of the undervoltage protection, and it is typically implemented using a high-precision voltage stabilization chip. Furthermore, to enhance the anti-interference capability of the discharge circuit 22, filter capacitors are added to the input and output terminals of the second voltage comparator to filter out false triggering caused by power supply fluctuations or other interference signals.

[0071] Of course, a battery management system can be set up in the discharge branch 221. The battery management system is a complex system that includes multiple sensors for real-time monitoring of the status of the power battery 3, including voltage monitoring. During the discharge process of the power battery 3, the battery management system continuously obtains voltage information of the power battery 3 and takes action when the voltage approaches the over-discharge threshold.

[0072] In the energy storage and discharge system of this specific embodiment, since the discharge branch 221 corresponds one-to-one to the power battery 3, during the discharge process, the discharge of the corresponding power battery 3 can be controlled by the corresponding discharge branch 221, and targeted control can be performed on the specific power battery 3, and the control process is convenient.

[0073] In a specific embodiment, each charging branch 211 may be provided with a first status indicator light for displaying the charging status. When the charging branch 211 is in the charging state, the first status indicator light is on; in other states, the first status indicator light is off.

[0074] It should be noted that the first status indicator light in this specific embodiment can be set to a position that is convenient for observation, or the status information of the first status indicator light can be displayed through an external display screen. The specific determination depends on the actual situation and will not be elaborated here.

[0075] In order to prevent the judgment of the charging status of the charging branch 211 from being affected by the failure of the first status indicator light itself, multiple first status indicator lights can be set in the same charging branch 211 to avoid the situation where individual first status indicator lights fail.

[0076] On the other hand, different signal information can also be transmitted by controlling the different flashing forms of the first status indicator light; specifically, when charging is completed, the first status indicator light can be controlled to indicate frequently and continuously; or other control methods can be determined according to actual conditions and will not be elaborated here.

[0077] During actual use, when the charging branch 211 is in the charging state, the first status indicator light is on. By observing the state of the first status indicator light, the staff can quickly determine the operating status of the charging branch 211. When charging is completed, the first status indicator light is off, and the staff can promptly obtain the information that charging has ended so that they can perform the relevant operations to end charging. If a fault occurs in the charging circuit 21 and the first status indicator light unexpectedly goes off, the staff can promptly obtain the fault information, facilitating timely maintenance. In addition, in this specific embodiment, each charging branch 211 is provided with a first status indicator light. During actual use, it is convenient to determine which charging branch 211 has a fault, thereby shortening maintenance time.

[0078] On the basis of the above embodiment, any discharge branch 221 may be provided with a second status indicator light for displaying the discharge status. When the discharge branch 221 is in the discharge status, the second status indicator light is on, and in other statuses, the second status indicator light is off.

[0079] It should be noted that the second status indicator light in this specific embodiment can be set to a position that is convenient for observation, or the status information of the second status indicator light can be displayed through an external display screen. The specific determination depends on the actual situation and will not be elaborated here.

[0080] In order to prevent the failure of the second status indicator light in the discharge branch 221 from affecting the judgment of the discharge state of the discharge branch 221, multiple second status indicator lights can be set in the same discharge branch 221 to avoid the situation where individual second status indicator lights fail.

[0081] On the other hand, different signal information can be transmitted by controlling the different flashing forms of the second status indicator light; specifically, when the discharge is completed, the second status indicator light can be controlled to indicate frequently and continuously; or other control methods can be determined according to actual conditions and will not be elaborated here.

[0082] During actual use, when the discharge branch 221 is in the discharge state, the second status indicator light is on. By observing the state of the second status indicator light, the staff can quickly determine the operating status of the discharge branch 221. When the discharge is completed, the second status indicator light is off. The staff can promptly obtain the information that the discharge has ended so that they can perform the relevant operations to end the discharge. When the discharge circuit 22 fails and the second status indicator light unexpectedly goes off, the staff can promptly obtain the fault information, facilitating timely maintenance. In addition, in this specific embodiment, each discharge branch 221 is provided with a second status indicator. During actual use, it is convenient to determine which discharge branch 221 has failed, thereby shortening maintenance time.

[0083] In a specific embodiment, the traction converter 2 may further include an auxiliary inverter 24; in the discharging state, one end of the auxiliary inverter 24 is connected to the first circuit, and the other end is used to connect to the electrical equipment; in the charging state, one end of the auxiliary inverter 24 is connected to the first circuit, and the other end is used to connect to the power supply equipment 5.

[0084] Furthermore, a third control switch for controlling whether the auxiliary inverter 24 is connected to the first circuit may be provided on the connection circuit between the auxiliary inverter 24 and the first circuit.

[0085] It should be noted that the auxiliary inverter 24 in this specific embodiment is a power electronic device that converts direct current (DC) into alternating current (AC). In systems that include a power battery 3, such as electric vehicles and electric trains, the auxiliary inverter 24 is primarily used to provide the AC power required by auxiliary equipment on the vehicle (such as air conditioning systems, air compressors, and lighting systems). Because these auxiliary equipment typically requires AC power of varying frequencies and voltage levels to operate, the auxiliary inverter 24 converts the DC power from the power battery 3 into AC power that meets the equipment's requirements.

[0086] In actual use, by controlling the opening and closing of the third control switch, the auxiliary inverter 24 can be connected to the first circuit or disconnected from the first circuit, so that the auxiliary inverter 24 can be selectively used.

[0087] Under normal operating conditions, the auxiliary inverter 24 can be connected to the DC bus to invert the output AC380V to power the train. Specifically, in addition to powering the train, it can also power other electrical devices that require power. In the event of a hydrogen fuel cell 1 failure, the auxiliary inverter 24 can be connected to the power supply device 5, drawing power from the workshop power supply. The current from the power supply device 5 is reverse-rectified and boosted through the auxiliary inverter 24 and auxiliary transformer. The auxiliary inverter 24 is then connected to the first circuit to charge the power battery 3 through the charging circuit 21.

[0088] On the basis of the above embodiment, the traction converter 2 further includes a transformer, which is detachably connected to the auxiliary inverter 24 .

[0089] The combination of a transformer and auxiliary inverter 24 can provide voltage adaptation and stable power supply. The transformer itself can change the AC voltage. When combined with the auxiliary inverter 24, if the hydrogen fuel cell 1 in this embodiment fails and requires an external power supply device 5, the transformer can first adjust the AC voltage input from the power supply device 5 to an appropriate input voltage range for the auxiliary inverter 24 on the input side. For example, in some industrial applications, the grid voltage may be as high as 10kV or 35kV, which is reduced by a step-down transformer to a voltage level of several hundred volts acceptable to the auxiliary inverter 24, such as 380V or 480V. In addition, during operation, the auxiliary inverter 24 may be affected by factors such as input voltage fluctuations and load changes, resulting in unstable output voltage. The transformer can provide a certain degree of buffering and voltage stabilization. For example, when a sudden increase in load causes the output voltage of the auxiliary inverter 24 to decrease, the electromagnetic induction characteristics of the transformer can counteract this voltage change through changes in its own magnetic flux, keeping the output voltage relatively stable and providing a reliable power supply for the load equipment.

[0090] In this specific embodiment, the combination of a transformer and auxiliary inverter 24 also provides electrical isolation and safety protection. Specifically, the transformer provides electrical isolation between the input and output. In the combined system, this means that the input and output sides of the auxiliary inverter 24 are electrically independent. For example, in the power system, when an electrical fault (such as a short circuit or lightning strike) occurs on the grid side, the transformer can prevent the fault current from directly transmitting to the auxiliary inverter 24 and the load equipment, thereby protecting the auxiliary inverter 24 and the load. This isolation also reduces the propagation of electromagnetic interference (EMI) between the input and output. For example, high-frequency EMI from the grid side is not easily transmitted to the load equipment through the transformer, thereby improving the electromagnetic compatibility of the entire system. Furthermore, electrical isolation provides a safer working environment for operators and equipment maintenance personnel. Because the transformer isolates the high and low voltage sides, the risk of electric shock when human contact with the load equipment is reduced. For example, in safety-critical environments such as hospitals and laboratories, the isolation provided by the transformer can ensure user safety even if the auxiliary inverter 24 fails.

[0091] In a specific embodiment, there are multiple traction motors 4 , which are arranged in parallel, and a fourth control switch is provided between any traction motor 4 and the traction inverter 23 .

[0092] When the energy storage and discharge system in this specific embodiment is applied to a hydrogen-powered train, the traction motor 4 primarily converts electrical energy into mechanical energy to propel the train forward. In a hydrogen-powered train, the direct current generated by the hydrogen fuel cell 1 is converted to alternating current by the traction inverter 23 and then supplied to the traction motor 4. The traction motor 4 operates based on the principle of electromagnetic induction. When alternating current is passed through the motor's stator windings, a rotating magnetic field is generated within the stator. This rotating magnetic field cuts through the conductors on the motor's rotor (e.g., the squirrel-cage windings in the case of an asynchronous traction motor 4), generating an induced electromotive force and an induced current in the rotor conductors according to the law of electromagnetic induction. The rotor current in the rotating magnetic field is acted upon by the Ampere force, which causes the rotor to rotate with the rotating magnetic field, thereby converting electrical energy into mechanical energy.

[0093] In hydrogen-fueled electric trains, the synchronized operation of multiple traction motors 4 is crucial. Train operation requires stable and coordinated traction. If the traction motors 4 are out of sync, uneven forces will be applied to the train's axles. For example, during train startup and acceleration, if some motors have high output power and others have low output power, the train may veer off course or experience wheel spin, impacting normal operation and even damaging the track and wheels. In this specific embodiment, a fourth control switch is provided between each traction motor 4 and the traction inverter 23. By controlling the synchronized start and stop of the fourth control switch, synchronized operation of the multiple traction motors 4 can be achieved.

[0094] In actual use, by controlling the opening and closing of the fourth control switch, the synchronous start and stop of multiple traction motors 4 can be accurately controlled, or by controlling the corresponding fourth control switch, the operation of the corresponding traction motor 4 can be controlled.

[0095] In addition to the above-mentioned energy storage and discharge system, the present invention also provides a hydrogen-powered motor vehicle including the energy storage and discharge system disclosed in the above-mentioned embodiment. For the structures of other parts of the hydrogen-powered motor vehicle, please refer to the prior art and will not be described in detail herein.

[0096] The hydrogen-powered electric vehicle provided in this specific embodiment includes a hydrogen fuel cell system 1, a power system, an energy storage system, a body and running system, and an electrical control system, wherein the hydrogen fuel cell system 1 includes a fuel cell stack, a hydrogen supply system, an oxygen supply system, and a cooling system; the power system includes a traction motor 4, a traction inverter 23, and a transmission device; the energy storage system includes a battery pack or a supercapacitor, and an energy management system (EMS); the body and running system includes a body structure, a steering gear, and a braking system; the electrical control system includes a train control unit (TCU), a sensor system, and a communication system.

[0097] Under traction conditions, when the hydrogen-powered train needs to accelerate, the traction motor 4 requires more power. At this time, the hydrogen fuel cell 1 system will adjust the hydrogen supply and reaction rate according to the train's power requirements. For example, by increasing the hydrogen intake, more hydrogen is allowed to participate in the chemical reaction, thereby generating more electrical energy. At the same time, the air supply system will also increase the intake accordingly, because the hydrogen fuel cell 1 reaction requires oxygen as a reactant to ensure that hydrogen and oxygen can react in an appropriate ratio. The energy management system of the hydrogen-powered train will coordinate the relationship between the hydrogen fuel cell 1, the energy storage system, and the traction motor 4. During acceleration, the power battery 3 of the energy storage system discharges simultaneously, and together with the hydrogen fuel cell 1, provides additional electrical energy to the traction motor 4 to meet the train's rapid acceleration requirements. Under this operating condition, the power battery 3 in this specific embodiment is connected to the first circuit via the discharge circuit 22. The power battery 3 and the hydrogen fuel cell 1 simultaneously supply power to the traction inverter 23, driving the traction motor 4 to operate and meet the power requirements of the traction motor 4.

[0098] In constant speed operation, after the train reaches the constant speed operation, the hydrogen-powered train enters a relatively stable operating state. At this time, the hydrogen fuel cell 1 outputs electrical energy at a relatively stable power, the hydrogen supply and reaction process remain stable, and the air supply also matches it. For example, hydrogen is stably supplied to the anode of the hydrogen fuel cell 1 at a certain speed, while ensuring that there is sufficient oxygen supply to the cathode, so that the chemical reaction continues to proceed stably, providing stable power for the train and maintaining the train's cruising speed. In the hydrogen-powered train in this specific embodiment, the hydrogen fuel cell 1 supplies power to the traction inverter 23 to drive the traction motor 4 to operate; at the same time, the hydrogen fuel cell 1 charges the power battery 3 through the charging circuit 21.

[0099] When a hydrogen-powered train needs to brake, a combination of mechanical braking and regenerative braking is generally used. In the initial stage of braking, regenerative braking is used first, and the traction motor 4 is transformed into a generator, converting the kinetic energy of the train into electrical energy. This part of the electrical energy can be stored in the energy storage system or consumed in the form of heat energy through the braking resistor; when the hydrogen-powered train in this specific embodiment is in the regenerative braking condition, the traction motor 4 is converted to the power generation state, and the AC power is reverse-rectified into DC power by the traction inverter 23, and the power battery 3 is charged through the charging circuit 21. Multiple groups of parallel power batteries 3 control the charging current separately in the charging circuit 21.

[0100] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other. Any combination of all the embodiments provided by this utility model is within the scope of protection of this utility model and will not be described in detail here.

[0101] The above is a detailed introduction to the energy storage and discharge system and hydrogen-powered electric vehicle provided by the present invention. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only intended to help understand the method and core concept of the present invention. It should be noted that for ordinary technicians in this technical field, without departing from the principles of the present invention, the present invention can also be improved and modified, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. An energy storage and discharge system, characterized in that: It includes a hydrogen fuel cell (1), a traction converter (2), a plurality of power batteries (3) connected in parallel, and a traction motor (4); The traction converter (2) comprises a charging circuit (21), a discharging circuit (22) and a traction inverter (23); the hydrogen fuel cell (1) and the traction inverter (23) are electrically connected via a first circuit, and one end of each of the charging circuit (21) and the discharging circuit (22) is electrically connected to the first circuit and the other end is electrically connected to the power battery (3).

2. The energy storage and discharge system according to claim 1, characterized in that: The charging circuit (21) is provided with charging branches (211) corresponding one to one with the power batteries (3), and any of the charging branches (211) is provided with a first control switch.

3. The energy storage and discharge system according to claim 2, characterized in that: The discharge circuit (22) is provided with discharge branches (221) for corresponding one-to-one with the power batteries (3), and any of the discharge branches (221) is provided with a second control switch.

4. The energy storage and discharge system according to claim 3, characterized in that: Any of the charging branches (211) is provided with a first status indicator light for displaying the charging status; when the charging branch (211) is in the charging state, the first status indicator light is on.

5. The energy storage and discharge system according to claim 4, characterized in that: Any of the discharge branches (221) is provided with a second status indicator light for displaying a discharge status; when the discharge branch (221) is in a discharge status, the second status indicator light is on.

6. The energy storage and discharge system according to claim 1, characterized in that: The traction converter (2) further includes an auxiliary inverter (24); In the discharge state, one end of the auxiliary inverter (24) is connected to the first circuit, and the other end is used to connect to the electrical equipment; In the charging state, one end of the auxiliary inverter (24) is connected to the first circuit, and the other end is used to connect to the power supply device (5).

7. The energy storage and discharge system according to claim 6, characterized in that: A third control switch for controlling whether the auxiliary inverter (24) is connected to the first circuit is provided on the connection circuit between the auxiliary inverter (24) and the first circuit.

8. The energy storage and discharge system according to claim 6, characterized in that: The traction converter (2) further comprises a transformer, which is detachably connected to the auxiliary inverter (24).

9. The energy storage and discharge system according to any one of claims 1 to 7, characterized in that: There are multiple traction motors (4), and the multiple traction motors (4) are arranged in parallel. A fourth control switch is provided between any of the traction motors (4) and the traction inverter (23).

10. A hydrogen-powered electric vehicle, characterized in that: An energy storage and discharge system comprising the energy storage and discharge system according to any one of claims 1 to 9.

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