Urban rail vehicle storage battery emergency starting circuit and starting method

Abstract

The invention provides an emergency starting circuit and method for a storage battery of an urban rail vehicle. The starting circuit comprises a storage battery; the storage battery is connected with a bus, a first output end of the bus is connected with a contactor K1, a second output end of the bus is connected with a contactor K2, a third output end of the bus is connected with a starting switch, and an output end of the starting switch is connected with an emergency voltage-stabilized power supply DC / DC; an emergency voltage-stabilized power supply DC / DC; the output end of the emergency voltage-stabilized source DC / DC is connected with the auxiliary inverter and the charger control circuit, the output end of the auxiliary inverter is connected with the charger, and the output end of the charger is connected with the storage battery and the load. According to the invention, through the specially designed emergency starting circuit, even if the storage battery triggers low-voltage protection, the auxiliary control unit and the charger unit can be started by using the residual electric quantity of the storage battery, and then the charger is started, so that normal operation of the urban rail vehicle can be quickly recovered.

Description

Technical Field

[0001] This invention relates to the field of urban rail transit technology, and more particularly to an emergency starting circuit and starting method for urban rail vehicle batteries. Background Technology

[0002] With the acceleration of urbanization, urban rail transit systems (such as subways and light rail) have become an important part of public transportation in large and medium-sized cities. Urban rail vehicles are usually equipped with battery packs as backup power to provide power support for critical equipment in the event of a main power failure. However, when the battery voltage drops below a preset low-voltage protection threshold, in order to protect the battery from deep discharge damage, the system will automatically disconnect the load and stop supplying power to the DC 110V load, including the auxiliary control unit and charger unit. This can cause the vehicle to fail to start or continue operating normally, resulting in operational interruption.

[0003] Traditionally, solutions to this problem include using an emergency voltage regulator (converting a DC 1500V power supply directly to DC 110V) or an external charger to charge the battery that has reached its low-voltage protection state. The first method requires an emergency voltage regulator with an isolated design to minimize the impact on the battery in case of a fault; it is expensive and has a high failure rate. The second method often involves an external charger not being on-site, making operation cumbersome and inefficient. Designing an additional independent emergency energy storage system is also an option, but this increases cost and system complexity. Therefore, there is an urgent need to develop a technical solution that can quickly restore power and restart urban rail vehicles in emergency situations without adding excessive hardware burden and utilizing existing resources. Summary of the Invention

[0004] To address the aforementioned technical problems of high failure rate and low efficiency in existing low-voltage battery starting methods, this invention provides an emergency starting circuit and method for urban rail vehicle batteries. Through a specially designed emergency starting circuit, this invention enables the use of the battery's remaining charge to start the auxiliary control unit and charger unit, and subsequently the charger, even when the battery has triggered low-voltage protection, thus ensuring that the urban rail vehicle can quickly resume normal operation.

[0005] The technical means employed in this invention are as follows: An emergency starting circuit for a city rail vehicle battery includes: Storage battery; the storage battery is connected to the busbar, the first output terminal of the busbar is connected to contactor K1, the second output terminal of the busbar is connected to contactor K2, the third output terminal of the busbar is connected to the start switch, and the output terminal of the start switch is connected to the emergency voltage regulator DC / DC. An emergency voltage regulator DC / DC converter; the output terminals of the emergency voltage regulator DC / DC converter are respectively connected to the auxiliary inverter and the charger control circuit, the output terminal of the auxiliary inverter is connected to the charger, and the output terminal of the charger is respectively connected to the battery and the load. An isolation diode D1 is installed between the bus and the charger control circuit of the charger and the auxiliary inverter control circuit of the auxiliary inverter.

[0006] Furthermore, when the urban rail vehicle needs to be activated, the contactor K1 is activated and closed, and the battery discharges to provide power to the load; when the vehicle stops operating, the contactor K1 is opened, and the contactor K1 automatically opens when the battery voltage is low.

[0007] Furthermore, the contactor K2 is an emergency charging contactor for the battery; when the battery voltage is low and the contactor K1 is open, the start switch is closed, and the charger enters the emergency start mode. When the charger output voltage reaches the rated DC110V, the charger closes the contactor K2 to charge the battery. After the charger starts, the contactor K1 closes, and the start switch is opened. After the charger detects that the start switch is open, it opens the contactor K2.

[0008] Furthermore, when the battery voltage is below 80V, it is determined to be a low battery voltage.

[0009] Furthermore, the auxiliary inverter includes an auxiliary inverter control circuit and an auxiliary inverter main circuit connected together. The auxiliary inverter main circuit is connected to a DC1500V high-voltage circuit, and the auxiliary inverter main circuit converts the DC1500V voltage into a three-phase AC380V voltage and transmits it to the charger main circuit. The charger includes a connected charger control circuit and a charger main circuit. The charger main circuit converts the three-phase AC380V voltage into DC110V voltage and transmits it to the load and the battery.

[0010] Furthermore, the input voltage of the emergency voltage regulator DC / DC is DC60V~110V, the output voltage of the emergency voltage regulator DC / DC is DC110V, and the voltage of the load is DC110V.

[0011] The present invention also provides an emergency starting method for urban rail vehicle batteries, implemented based on any of the above-mentioned urban rail vehicle battery emergency starting circuits, comprising the following steps: S1. When the battery voltage is below 80V or the contactor K1 is under-voltage disconnected and the battery voltage is above 60V, perform emergency battery start-up. S2. Press the start switch to start the emergency voltage regulator DC / DC, which will stably output the battery power to DC110V. The output of the emergency voltage regulator DC / DC will provide power to the auxiliary inverter and charger control circuit. S3, the auxiliary inverter works to provide three-phase AC380V power to the charger; S4. When the charger detects that the start switch is closed and contactor K1 is open, the charger starts to work, providing DC 110V output, and at the same time closes contactor K2 to charge the battery. S5. After observing that the battery voltage reaches DC110V, close contactor K1 and then open the start switch. When the charger detects that contactor K2 is closed and the start switch is open, it will disconnect contactor K2, and the emergency start of the battery will be completed.

[0012] Compared with the prior art, the present invention has the following advantages: This invention, through a specially designed emergency start circuit, enables the auxiliary control unit and charger unit to be started even when the battery has triggered low-voltage protection, thereby starting the charger and ensuring that urban rail vehicles can quickly resume normal operation, reducing service interruption time caused by power failure.

[0013] The entire emergency battery start-up process is based on the initial stage of battery depletion, where the system has implemented undervoltage protection but cannot support full system startup. It fully utilizes the remaining battery power, employing an emergency DC / DC power supply to stabilize the battery voltage at DC 110V, ensuring startup only for necessary loads such as auxiliary inverters and chargers. Due to the short operating time and very low battery discharge rate, there is almost no damage to the system, resulting in a very high startup success rate. The system cost can be significantly reduced compared to existing high-voltage start-up power supply solutions. Because the emergency DC / DC power supply operates for a very short time, the product's failure rate is also significantly lower than existing high-voltage start-up power supply solutions. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a circuit diagram for the emergency starting circuit of the urban rail vehicle battery of the present invention.

[0016] Figure 2 This is a timing diagram for the emergency start-up of the battery according to the present invention.

[0017] In the diagram: 1. Emergency regulated DC / DC power supply; 2. Start switch; 3. Contactor K1; 4. Contactor K2; 5. Isolation diode D1; 6. Auxiliary inverter; 7. Charger; 8. Battery. Detailed Implementation

[0018] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0019] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0021] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0022] like Figure 1 As shown, the present invention provides an emergency starting circuit for urban rail vehicle batteries, comprising: Battery 8; the battery 8 is connected to the busbar, the first output terminal of the busbar is connected to contactor K1 3, the second output terminal of the busbar is connected to contactor K2 4, the third output terminal of the busbar is connected to start switch 2, and the output terminal of start switch 2 is connected to emergency voltage regulator DC / DC 1. Emergency voltage regulator DC / DC 1; the output terminals of the emergency voltage regulator DC / DC 1 are respectively connected to the control circuits of the auxiliary inverter 6 and the charger 7, the output terminal of the auxiliary inverter 6 is connected to the charger 7, and the output terminal of the charger 7 is respectively connected to the battery 8 and the load. An isolation diode D15 is provided between the bus and the charger control circuit of the charger 7 and the auxiliary inverter control circuit of the auxiliary inverter 6.

[0023] The emergency voltage regulator DC / DC is an emergency voltage regulator that can stabilize the DC60V~110V voltage at DC110V. Especially in the early stage of battery depletion, it can provide power to the auxiliary inverter and charger control circuit, enabling the charger to start and replenish the battery.

[0024] The start switch can be installed in a convenient location such as the driver's cab. When the battery is low on power (generally when the battery voltage is below 80V or when the contactor K1 is disconnected due to undervoltage), the start switch can be manually operated to provide power to the emergency start DC / DC converter, thereby providing power to the auxiliary inverter and charger control circuit, starting the charger and replenishing the battery.

[0025] The contactor K1 is activated and closed by external operation when the urban rail vehicle needs to be activated, allowing the battery to discharge and provide power to the DC110V load. When the vehicle stops operating, it can be manually activated and closed. At the same time, to prevent the battery voltage from being undervoltage, it can be automatically disconnected when the battery voltage is low (below 80V) to prevent the battery from being over-discharged.

[0026] The contactor K2 is an emergency charging contactor for the battery. When the battery voltage is low and the contactor K1 is open, pressing the start switch will cause the charger to detect that the start switch is closed and enter the emergency start mode. When the charger output voltage reaches the rated DC110V, the charger will close the contactor K2 to charge the battery. After the charger starts, the contactor K1 will close, and the start switch will be opened. After the charger detects that the start switch is open, it will disconnect the contactor K2.

[0027] The isolation diode D1 isolates the DC110V bus from the charger control circuit and the auxiliary inverter control circuit. The purpose is to prevent the emergency regulated power supply DC / DC from providing DC110V control power to the charger and auxiliary inverter, thereby supplying additional power to other loads on the DC110V bus and reducing the load power.

[0028] The auxiliary inverter typically uses DC 1500V power supply to convert DC 1500V into three-phase AC 380V to provide power to the charger.

[0029] The charger converts the three-phase AC380V provided by the auxiliary inverter into DC110V to power the DC110V load and simultaneously charges the battery. The charger monitors the start switch status in real time. When the start switch is closed, due to the isolation diode D1, the emergency regulated DC / DC power supply only powers the necessary starting equipment, the auxiliary inverter, and the charger, preventing over-discharge when the battery voltage is low. After the charger starts, it closes the contactor K2 to power the battery, achieving a balanced power supply state.

[0030] The battery provides backup control power for the urban rail vehicle. When the charger is not started, the battery provides power to the control system. When the charger is started, the battery mainly provides output filtering and backup power for the charger.

[0031] This invention fully utilizes the remaining energy stored in the battery after the voltage drops below 80V or the main contactor K1 is disconnected due to undervoltage. An emergency DC / DC power supply provides 110V DC power to the necessary control circuits of the system, ensuring system startup. By fully utilizing the low-voltage region of the battery, critical loads are started with low power before the battery is completely discharged, achieving emergency charging of the battery and preventing further battery depletion.

[0032] This invention also proposes an emergency start method for urban rail vehicle batteries, wherein the emergency start sequence of the battery is as follows: Figure 2 The method includes the following steps: S1. When the battery voltage is below 80V or the contactor K1 is under-voltage disconnected and the battery voltage is above 60V, emergency battery start-up can be used. S2. Press the start switch to start the emergency voltage regulator DC / DC, which will stably output the battery power to DC110V and provide power to the auxiliary inverter and charger control circuit through the output terminal. S3, the auxiliary inverter works to provide three-phase AC380V power to the charger; S4. When the charger detects that the start switch is closed and contactor K1 is open, the charger starts to work, providing DC 110V output, and at the same time closes contactor K2 to charge the battery. S5. After observing that the battery voltage reaches DC110V, manually close contactor K1, and then open the start switch. When the charger detects that contactor K2 is closed and the start switch is open, it will disconnect contactor K2, and the emergency start of the battery is completed.

[0033] The entire emergency battery startup process is designed for situations where the battery is initially depleted, the system has undervoltage protection but cannot support full system startup, and the remaining battery power is fully utilized. An emergency DC / DC power supply stabilizes the battery voltage at DC 110V, ensuring startup only for necessary loads such as auxiliary inverters and chargers. Due to the short operating time and very low battery discharge rate, there is almost no damage to the system, resulting in a very high startup success rate. The system cost can be significantly reduced compared to existing high-voltage starting power supply solutions. Because the DC / DC power supply operates for a very short time, the product's failure rate is also significantly lower than existing high-voltage starting power supply solutions.

[0034] Example like Figure 1 As shown, this invention provides an emergency starting circuit for urban rail vehicle batteries. This circuit can be started manually, with the start switch located in a convenient position, such as the driver's cab. When the start switch is pressed, the emergency regulated voltage stabilizes the input voltage (DC60V~DC110V) at DC110V. This regulated power supply boosts the low voltage of the battery to provide power to the control circuits of the auxiliary inverter and charger in emergencies. If contactor K1 is open at this time, contactor K2 automatically closes when the charger output reaches DC110V to charge the battery. When the battery voltage reaches DC110V, contactor K1 can be manually closed. Upon detecting the open contactor K1, the charger automatically opens contactor K2, completing the emergency battery start-up.

[0035] The main function of the start switch is to control the start and stop of the emergency voltage regulator and provide an emergency start status signal to the charger. The main function of the auxiliary inverter is to convert DC 1500V to three-phase AC 380V to power the charger. The charger's function is to charge the battery and power the DC 110V load. Since this solution only powers the necessary load during emergency start-up, the power of the emergency voltage regulator (DC / DC converter) is significantly reduced. Calculations show that the power of the emergency voltage regulator (DC / DC converter) is only about 2kW. Furthermore, since the emergency voltage regulator does not operate when the battery is working normally, its lifespan is greatly extended. Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An emergency starting circuit for a city rail vehicle battery, characterized in that, include: Storage battery; the storage battery is connected to the busbar, the first output terminal of the busbar is connected to contactor K1, the second output terminal of the busbar is connected to contactor K2, the third output terminal of the busbar is connected to the start switch, and the output terminal of the start switch is connected to the emergency voltage regulator DC / DC. An emergency voltage regulator DC / DC converter; the output terminals of the emergency voltage regulator DC / DC converter are respectively connected to the auxiliary inverter and the charger control circuit, the output terminal of the auxiliary inverter is connected to the charger, and the output terminal of the charger is respectively connected to the battery and the load. An isolation diode D1 is installed between the bus and the charger control circuit of the charger and the auxiliary inverter control circuit of the auxiliary inverter.

2. The emergency starting circuit for urban rail vehicle batteries according to claim 1, characterized in that, When the urban rail vehicle needs to be activated, the contactor K1 is activated and closed, and the battery discharges to provide power to the load. When the vehicle is not in operation, the contactor K1 is disconnected, and the contactor K1 is automatically disconnected when the battery voltage is low.

3. The emergency starting circuit for urban rail vehicle batteries according to claim 1, characterized in that, The contactor K2 is an emergency charging contactor for the battery. When the battery voltage is low and the contactor K1 is open, the start switch is closed, and the charger enters the emergency start mode. When the charger output voltage reaches the rated DC110V, the charger closes the contactor K2 to charge the battery. After the charger starts, the contactor K1 closes, and the start switch is opened. After the charger detects that the start switch is open, it opens the contactor K2.

4. The emergency starting circuit for urban rail vehicle batteries according to claim 2 or 3, characterized in that, When the battery voltage is below 80V, it is determined to be a low battery voltage.

5. The emergency starting circuit for urban rail vehicle batteries according to claim 1, characterized in that, The auxiliary inverter includes an auxiliary inverter control circuit and an auxiliary inverter main circuit connected together. The auxiliary inverter main circuit is connected to a DC 1500V high voltage circuit. The auxiliary inverter main circuit converts the DC 1500V voltage into a three-phase AC 380V voltage and transmits it to the charger main circuit. The charger includes a connected charger control circuit and a charger main circuit. The charger main circuit converts the three-phase AC380V voltage into DC110V voltage and transmits it to the load and the battery.

6. The emergency starting circuit for urban rail vehicle batteries according to claim 1, characterized in that, The input voltage of the emergency voltage regulator DC / DC is DC60V~110V, and the output voltage of the emergency voltage regulator DC / DC is DC110V; the voltage of the load is DC110V.

7. A method for emergency starting a battery in an urban rail vehicle, implemented based on the emergency starting circuit for an urban rail vehicle battery as described in any one of claims 1-6, characterized in that, Includes the following steps: S1. When the battery voltage is below 80V or the contactor K1 is under-voltage disconnected and the battery voltage is above 60V, perform emergency battery start-up. S2. Press the start switch to start the emergency voltage regulator DC / DC, which will stably output the battery power to DC110V. The output of the emergency voltage regulator DC / DC will provide power to the auxiliary inverter and charger control circuit. S3, the auxiliary inverter works to provide three-phase AC380V power to the charger; S4. When the charger detects that the start switch is closed and contactor K1 is open, the charger starts to work, providing DC 110V output, and at the same time closes contactor K2 to charge the battery. S5. After observing that the battery voltage reaches DC110V, close contactor K1 and then open the start switch. When the charger detects that contactor K2 is closed and the start switch is open, it will disconnect contactor K2, and the emergency start of the battery will be completed.

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