Railway engineering vehicle power battery energy feedback charging control system and method

Abstract

The application discloses a kind of railway engineering car power battery energy feedback charging control system and method, control method includes the following steps: S101) when being in electric brake operating condition and running normally, the energy P consumed on auxiliary load is calculated 负载 ; S102) according to P 负载 , wheel circumference brake energy P 轮周 And the discharge current of charge-discharge unit judge whether the residual energy of intermediate DC circuit is positive, if yes, then execute step S103), if not, then jump to step S101) and execute;S103) calculate the electric brake energy allowed charging current value I1;S104) according to I1, and in combination with the allowed charging current value I 允 of power battery, calculate the charging current target value I 目标 = min (I1, I 允 );S105) according to I 目标 Control charge-discharge unit charges power battery.The application can solve the technical problems that the energy utilization rate of existing power battery charging control mode is not high, the system structure is complex, and the cost is higher.

Description

Technical Field

[0001] This invention relates to the field of railway engineering vehicle charging technology, and in particular to a power battery recharge control system and method for railway engineering vehicles in a power battery-assisted working mode. Background Technology

[0002] Currently, in the operation mode where the power battery is used as the locomotive's power source, the power battery provides energy to the vehicle under traction conditions. When in traction conditions, the power battery discharges through the reactor. When in resistance braking conditions, because the current flow direction of the reactor cannot change abruptly, the braking energy is generally dissipated through the heat energy of the braking resistor.

[0003] In the prior art, the following technical solutions are mainly related to this invention:

[0004] Prior art 1 is a Chinese invention application filed by Shenyang Microcontroller New Energy Technology Co., Ltd. on August 29, 2018, and published on January 4, 2019, with publication number CN109149634A. This invention discloses a regenerative energy recovery system based on flywheel energy storage and inverter feedback, comprising: at least one inverter feedback module, at least one flywheel energy storage feedback module, a detection module, and a voltage sensor. In this system, the inverter feedback module and the flywheel energy storage feedback module work in coordination, with regenerative energy primarily generated through inverter feedback, fully utilizing regenerative energy and solving the problem of backfeeding. Furthermore, the flywheel energy storage feedback module does not need to be configured according to the maximum power absorption requirement, resulting in better overall economic efficiency and energy-saving effect compared to single inverter feedback and flywheel energy storage feedback. The control method provided by this invention decouples the inverter feedback module and the flywheel energy storage feedback module in terms of control, eliminating the need for mutual communication, reducing the complexity of system control, and providing scalability, ease of construction, and convenient operation and maintenance. However, the invention mainly relates to a flywheel energy storage and feedback device for converting the regenerative energy generated during train braking into kinetic energy for storage or converting the stored kinetic energy into electrical energy for release by the train.

[0005] Prior art 2 is a Chinese invention application filed by the National University of Defense Technology of the Chinese People's Liberation Army on April 29, 2020, and published on July 24, 2020, with publication number CN111446889A. This invention discloses a controllable regenerative braking system and its control method based on a supercapacitor-energy-consuming resistor. The system includes a composite control unit, a supercapacitor, an energy-consuming resistor, a lithium battery power supply circuit, a supercapacitor power supply / braking circuit, an energy-consuming resistor braking circuit, and a motor drive bridge. The DC side of the motor drive bridge is connected to the positive and negative buses. The lithium battery power supply circuit, the supercapacitor power supply / braking circuit, and the energy-consuming resistor braking circuit are all connected to the positive and negative buses. The supercapacitor power supply / braking circuit includes a capacitor step-down bridge and a capacitor step-up bridge, and the energy-consuming resistor braking circuit includes an energy-consuming step-down bridge. This invention enables controllable motor speed and constant braking torque during supercapacitor-based regenerative braking, allowing for better application of supercapacitors in motor drive systems. The kinetic energy of the motor during braking can be stored in the supercapacitor as much as possible, and the switching of motor braking modes is seamless. However, this invention mainly focuses on describing the smooth control of the entire motor, where braking energy is recovered by a supercapacitor. Summary of the Invention

[0006] In view of this, the purpose of this invention is to provide a power battery charging control system and method for railway engineering vehicles, so as to solve the technical problems of low energy utilization, complex system structure and high cost of existing power battery charging control methods.

[0007] To achieve the aforementioned objectives, this invention specifically provides a technical implementation scheme for a power battery recharge control system for railway engineering vehicles. The power battery recharge control system for railway engineering vehicles includes: a central control unit, a power battery management system, a transmission control unit, an intermediate DC circuit, a three-phase controllable unit, a charging and discharging unit, a traction inverter unit, an auxiliary inverter unit, a power battery, a traction motor, auxiliary loads, and a discharge current sensor. The three-phase controllable unit, the charging and discharging unit, the traction inverter unit, and the auxiliary inverter unit are all connected to the intermediate DC circuit. When in electric braking mode, the traction motor acts as a generator to transfer the wheel braking energy P... 轮周 The wheel circumference braking energy P is input to the intermediate DC circuit through the traction inverter unit. 轮周 The energy consumed by the intermediate DC circuit and then by the auxiliary inverter unit on the auxiliary load is P. 负载 The central control unit is based on P 轮周 *η1、P 负载 The magnitude of / η2 and the value collected by the discharge current sensor determine whether the charging state has been entered. η1 is the rectification efficiency of the traction inverter unit, and η2 is the inverter efficiency of the auxiliary inverter unit. When P 轮周 *η1 is greater than P负载 When the discharge current of the charging and discharging unit collected by the discharge current sensor is ≤0, it is determined that there is remaining braking energy to prioritize charging the power battery, which is converted into an electric braking energy allowable charging current value I1. This is then combined with the power battery allowable charging current value I output by the power battery management system. 允 Calculate the target value of the charging current I. 目标 =min(I1,I 允 The remaining braking energy is transmitted from the intermediate DC circuit through the charging and discharging unit, and then through the transmission control unit according to the target charging current value I. 目标 The charging and discharging unit controls the charging of the power battery.

[0008] Furthermore, the energy P consumed on the auxiliary load 负载 Calculate using the following formula:

[0009]

[0010] Among them, U 有效 I represents the effective value of the output phase voltage of the auxiliary inverter unit acquired by the voltage sensor. 有效 This is the effective value of the output phase current of the auxiliary inverter unit, collected by the current sensor.

[0011] Furthermore, the allowable charging current I1 for the electric braking energy is calculated according to the following formula:

[0012] I1=(P 轮周 *η1-P 负载 / η2) / U0

[0013] Wherein, U0 is the intermediate DC voltage of the intermediate DC circuit.

[0014] Furthermore, the system also includes a traction generator set control unit and a traction generator set, wherein the traction generator set, the three-phase controllable unit, and the intermediate DC circuit are connected in sequence. The traction generator set control unit is connected to the traction generator set, and the electrical energy generated by the traction generator set is rectified by the three-phase controllable unit and output to the intermediate DC circuit. The traction generator set control unit controls the traction generator set.

[0015] Furthermore, the system also includes a chopper unit and a braking resistor, with the intermediate DC circuit, including the chopper unit and the braking resistor, connected in sequence. When the remaining energy of the electric braking exceeds the charging capacity of the power battery, the transmission control unit controls the chopper unit to dissipate the excess energy onto the braking resistor.

[0016] The present invention also provides a technical implementation scheme for a power battery recharge control method for railway engineering vehicles, which includes the following steps:

[0017] S101) In traction generator, power battery, or hybrid power mode, when in electric braking condition and operating normally, calculate the energy P consumed on the auxiliary load. 负载 ;

[0018] S102) Based on the energy P consumed on the auxiliary load 负载 Wheel circumferential braking energy P 轮周 The remaining energy in the intermediate DC circuit is determined by the discharge current of the charging and discharging unit. If it is positive, the process continues to step S103; otherwise, the process jumps to step S101.

[0019] S103) Calculate the allowable charging current value I1 for electric braking energy;

[0020] S104) Based on the allowable charging current value I1 of the electric braking energy, and in conjunction with the allowable charging current value I of the power battery 允 Calculate the target value of the charging current I. 目标 =min(I1,I 允 );

[0021] S105) According to the target charging current value I 目标 The charging and discharging unit controls the charging of the power battery.

[0022] Furthermore, in step S101), the energy P consumed on the auxiliary load... 负载 Calculate using the following formula:

[0023]

[0024] Among them, U 有效 I represents the effective value of the output phase voltage of the auxiliary inverter unit acquired by the voltage sensor. 有效 This is the effective value of the output phase current of the auxiliary inverter unit, collected by the current sensor.

[0025] Further, in step S103), the allowable charging current value I1 for electric braking energy is calculated according to the following formula:

[0026] I1=(P 轮周 *η1-P 负载 / η2) / U0

[0027] Among them, P 轮周 P represents the wheel circumferential braking energy, η1 represents the rectification efficiency of the traction inverter unit, and P represents the rectifier efficiency of the traction inverter unit. 负载The energy consumed by the auxiliary load is η2, which is the inverter efficiency of the auxiliary inverter unit, and U0 is the intermediate DC voltage of the intermediate DC circuit.

[0028] Further, step S102) includes:

[0029] According to P 轮周 *η1、P 负载 The magnitude of / η2 and the collected values ​​of the discharge current sensor are used to determine whether the remaining energy in the intermediate DC circuit is positive. When P 轮周 *η1 is greater than P 负载 When the discharge current of the charging and discharging unit collected by the discharge current sensor is ≤0, it is determined that there is remaining braking energy in the intermediate DC circuit at this time, which is preferentially used to charge the power battery and converted into electric braking energy. The allowable charging current is I1.

[0030] Furthermore, the method further includes the following steps:

[0031] S106) When the intermediate DC voltage U0 of the intermediate DC circuit > U 开通 At this time, the remaining energy of the electric braking exceeds the charging capacity of the power battery, activating the discharge function of the chopper unit. The transmission control unit then controls the chopper unit to dissipate the excess energy onto the braking resistor. 开通 This is the turn-on voltage of the intermediate DC circuit. When the intermediate DC voltage U0 ≤ U... 关断 At that time, the discharge function of the chopper unit is turned off, U 关断 This is the turn-off voltage for the intermediate DC circuit.

[0032] By implementing the technical solution of the power battery charging control system and method for railway engineering vehicles provided by the present invention, the following beneficial effects are achieved:

[0033] (1) The power battery energy feeding and charging control system and method of the railway engineering vehicle of the present invention, when the rail vehicle with power battery is working in electric braking mode, the electric braking energy is given priority to charge the power battery, which can improve the energy utilization rate, and the system structure is simple and the cost is low.

[0034] (2) The power battery energy feeding and charging control system and method of the railway engineering vehicle of the present invention can determine the energy and current flow of the system by data calculation and sensor sampling, which can recover braking energy to the maximum extent and does not require additional energy storage device.

[0035] (3) The power battery energy feeding and charging control system and method for railway engineering vehicles of the present invention adopts braking energy recovery discrimination calculation and power battery charging control. The power battery is both a provider of traction energy and a receiver of braking energy. It does not require the installation of supercapacitors, flywheels and other energy storage components, thus saving system costs to the maximum extent.

[0036] (4) The power battery energy feeding and charging control system and method of the railway engineering vehicle of the present invention can adaptively adjust the charging current of the power battery by calculating and comparing the energy of the intermediate DC circuit, and can maximize the recovery of wheel braking energy. Attached Figure Description

[0037] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other embodiments can be obtained based on these drawings without creative effort.

[0038] Figure 1 This is a system control structure block diagram of a specific embodiment of the power battery recharge control system for railway engineering vehicles of the present invention;

[0039] Figure 2 This is a schematic block diagram of the power flow structure in hybrid mode of a specific embodiment of the power battery charging control system for railway engineering vehicles of the present invention.

[0040] Figure 3 This is an electrical structure topology diagram of a specific embodiment of the power battery charging control system for railway engineering vehicles of the present invention;

[0041] Figure 4 This is a flowchart of a specific embodiment of the power battery recharge control method for railway engineering vehicles of the present invention;

[0042] In the diagram: 1-Central control unit, 2-Traction generator set control unit, 3-Power battery management system, 4-Transmission control unit, 5-Intermediate DC circuit, 6-Three-phase controllable unit, 7-Charging and discharging unit, 8-Traction inverter unit, 9-Auxiliary inverter unit, 10-Traction generator set, 11-Power battery, 12-Traction motor, 13-Auxiliary load, 14-Chopper unit, 15-Braking resistor. Detailed Implementation

[0043] For the sake of clarity and reference, the technical terms, abbreviations, or acronyms used below will be recorded as follows:

[0044] DC / DC: Short for direct current / direct current converter;

[0045] AC / DC: Short for alternating current / direct current conversion;

[0046] DC / AC: Short for DC / AC converter;

[0047] CCU: Central Control Unit;

[0048] BMS: Battery Management System, short for power battery management system;

[0049] DCU: Drive Control Unit;

[0050] ECU: Engine Control Unit.

[0051] 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 a part of the embodiments of the present invention, and not all of them. 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.

[0052] As attached Figure 1 To be continued Figure 4 As shown, a specific embodiment of the power battery charging control system and method for railway engineering vehicles of the present invention is given. The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0053] Example 1

[0054] like Figure 1 As shown, the hardware control unit involved in Embodiment 1 of the present invention includes functional modules such as a central control unit 1, a traction generator set control unit 2, a power battery management system 3, and a transmission control unit 4. The central control unit 1 (CCU) communicates with the transmission control unit 4 (DCU) via MVB (Multifunction Vehicle Bus), and the central control unit 1 (CCU) communicates with the power battery management system (BMS) 3 and the traction generator set control unit (ECU) 2 via CAN (Controller Area Network).

[0055] As attached Figure 2As shown, the main hardware circuit unit involved in Embodiment 1 of the present invention includes a three-phase controllable (AC / DC rectifier) ​​unit 6, a (DC / DC) charging and discharging unit 7 (including reactor L1), an intermediate DC circuit 5, a traction inverter (DC / AC) unit 8, an auxiliary inverter (DC / AC) unit 9, a traction generator set 10, a power battery 11, a traction motor 12, an auxiliary load 13, a (DC / DC) chopper unit 14, and a braking resistor 15, etc. The three-phase AC power output from the traction generator set 10 (which can specifically be a diesel generator set) powers the intermediate DC circuit 5 after passing through the three-phase controllable (AC / DC rectifier) ​​unit 6. The power battery 11 powers the intermediate DC circuit 5 after passing through the (DC / DC) charging and discharging unit 7 (boost voltage), together serving as the power source for the railway engineering vehicle. The two power supplies are connected in parallel in the intermediate DC circuit 5. After passing through the traction inverter (DC / AC) unit 8 and the auxiliary inverter (DC / AC) unit 9, they are output to the traction motor 12 (which can be an asynchronous traction motor or a permanent magnet synchronous motor) and the auxiliary load 13, respectively.

[0056] As attached Figure 1 , 2 As shown in Figure 3, an embodiment of the power battery charging control system for railway engineering vehicles of the present invention specifically includes: a central control unit 1, a power battery management system 3, a transmission control unit 4, an intermediate DC circuit 5, a three-phase controllable unit 6, a charging and discharging unit 7, a traction inverter unit 8, an auxiliary inverter unit 9, a power battery 11, a traction motor 12, an auxiliary load 13, and a discharge current sensor A3. The three-phase controllable unit 6, the charging and discharging unit 7, the traction inverter unit 8, and the auxiliary inverter unit 9 are all connected to the intermediate DC circuit 5. The discharge current sensor A3 is connected between the charging and discharging unit 7 and the power battery 11. When the railway engineering vehicle operates in traction generator set (diesel engine set) mode, power battery mode, or hybrid mode (diesel engine set and power battery 11 operate simultaneously), under electric braking conditions, the traction inverter unit 8 operates in rectification mode, and the traction motor 12 acts as a generator to convert the wheel braking energy P... 轮周 The input is fed to the intermediate DC circuit 5 via the traction inverter unit 8, P 轮周 The electric braking power at the wheel circumference generated by the given traction motor 12. Wheel circumference braking energy P. 轮周 The energy consumed by the intermediate DC circuit 5 and the auxiliary inverter unit 9 in the auxiliary load 13 is P. 负载 Central control unit 1 according to P 轮周 *η1、P 负载 The value of / η2 and the value collected by the discharge current sensor A3 determine whether the charging state has been entered. η1 is the rectification efficiency of the traction inverter unit 8, and η2 is the inverter efficiency of the auxiliary inverter unit 9. When P 轮周 *η1 is greater than P 负载When the discharge current of the charging and discharging unit 7 collected by the discharge current sensor A3 is ≤0, it is determined that there is remaining braking energy to charge the power battery 11 first, which is converted into an electric braking energy allowable charging current value I1. This is then combined with the power battery allowable charging current value I output by the power battery management system 3. 允 Calculate the target value of the charging current I. 目标 =min(I1,I 允 ), that is, the target value of the charging current I. 目标 The allowable charging current value I1 for electric braking energy and the allowable charging current value I of the power battery 允 The smaller value in the middle. The remaining braking energy is transmitted from the intermediate DC circuit 5 through the charging and discharging unit 7, and then through the transmission control unit 4 according to the target charging current value I. 目标 The charging and discharging unit 7 (step-down) controls the charging of the power battery 11.

[0057] As attached Figure 2 and attached Figure 3 The diagram shows the energy flow direction of the power battery charging control system for railway engineering vehicles in hybrid mode according to the present invention.

[0058] The central control unit 1 calculates the energy P consumed on the auxiliary load 13 by using the output phase voltage of the auxiliary inverter unit 9 collected by voltage sensor V3 and the output phase current of the auxiliary inverter unit 9 collected by current sensor A4. 负载 The energy P consumed on auxiliary load 13 负载 Further calculations are performed using the following formula:

[0059]

[0060] Among them, U 有效 I represents the effective value of the output phase voltage of the auxiliary inverter unit 9, acquired by voltage sensor V3. 有效 The effective value of the output phase current of the auxiliary inverter unit 9 is collected by the current sensor A4.

[0061] The allowable charging current value I1 for electric braking energy is further calculated according to the following formula:

[0062] I1=(P 轮周 *η1-P 负载 / η2) / U0

[0063] Wherein, U0 is the intermediate DC voltage of the intermediate DC circuit 5.

[0064] The power battery charging control system for railway engineering vehicles also includes a traction generator set control unit 2 and a traction generator set 10. The traction generator set 10, the three-phase controllable unit 6, and the intermediate DC circuit 5 are connected in sequence. The traction generator set control unit 2 is connected to the traction generator set 10. The electrical energy generated by the traction generator set 10 is rectified by the three-phase controllable unit 6 and output to the intermediate DC circuit 5. The traction generator set control unit 2 controls the traction generator set 10.

[0065] The power battery charging control system for railway engineering vehicles also includes a chopper unit 14 and a braking resistor 15. The intermediate DC circuit 5, including the chopper unit 14 and the braking resistor 15, is connected in sequence. When the remaining energy of the electric braking exceeds the charging capacity of the power battery 11, the transmission control unit 4 controls the chopper unit 14 to dissipate the excess energy on the braking resistor 15.

[0066] The railway engineering vehicle power battery regenerative braking energy recovery and battery charging technology described in Embodiment 1 of this invention relates to the field of urban rail transit regenerative braking energy recovery and battery charging technology. It is a railway engineering vehicle power battery regenerative braking energy recovery and charging control system and method in a power battery-in-operation mode. The hardware units involved include a central control unit 1, a traction generator set (engine) control unit 2, a power battery management system (power battery control unit) 3, a transmission control unit 4, and main circuit modules. Embodiment 1 uses sensor sampling and data calculation to determine the system's energy and current flow direction, achieving maximum recovery of braking energy without requiring additional energy storage devices. The railway engineering vehicle power battery regenerative braking control system uses braking energy recovery discrimination calculation and power battery charging control. The power battery 11 is both a provider of traction energy and a receiver of braking energy. When the railway engineering vehicle with battery power 11 operates in electric braking mode, the electric braking energy prioritizes charging the power battery 11, improving energy utilization. Simultaneously, the power battery 11 serves as both a provider of traction energy and a receiver of braking energy, eliminating the need for supercapacitors or other energy storage components, significantly reducing system costs.

[0067] Example 2

[0068] As attached Figure 4 As shown, an embodiment of the power battery charging control method for railway engineering vehicles of the present invention, based on the system described in Embodiment 1, specifically includes the following steps:

[0069] S101) In traction generator, power battery, or hybrid power mode, when in electric braking condition and operating normally, calculate the energy P consumed on auxiliary load 13. 负载 ;

[0070] S102) Based on the energy P consumed on the auxiliary load 13 负载 Wheel circumferential braking energy P轮周 The discharge current of the charging and discharging unit 7 is used to determine whether the remaining energy of the intermediate DC circuit 5 is positive. If it is, continue to execute step S103); otherwise, jump to step S101.

[0071] S103) Calculate the allowable charging current value I1 for electric braking energy;

[0072] S104) Based on the allowable charging current value I1 of the electric braking energy, and in conjunction with the allowable charging current value I of the power battery 允 Calculate the target value of the charging current I. 目标 =min(I1,I 允 );

[0073] S105) According to the target charging current value I 目标 The charging and discharging unit 7 controls the charging of the power battery 11 until the electric braking condition is discontinued.

[0074] In step S101), the energy P consumed on the auxiliary load 13 负载 Further calculations are performed using the following formula:

[0075]

[0076] Among them, U 有效 I represents the effective value of the output phase voltage of the auxiliary inverter unit 9, acquired by voltage sensor V3. 有效 The effective value of the output phase current of the auxiliary inverter unit 9 is collected by the current sensor A4.

[0077] In step S103), the allowable charging current value I1 for electric braking energy is further calculated according to the following formula:

[0078] I1=(P 轮周 *η1-P 负载 / η2) / U0

[0079] Among them, P 轮周 P represents the wheel circumferential braking energy, η1 represents the rectification efficiency of the traction inverter unit 8, and P represents the rectifier efficiency of the traction inverter unit 8. 负载 To dissipate the energy on the auxiliary load 13, η2 is the inverter efficiency of the auxiliary inverter unit 9, and U0 is the intermediate DC voltage of the intermediate DC circuit 5.

[0080] Step S102) further includes:

[0081] According to P 轮周 *η1、P 负载 The magnitude of / η2 and the value collected by the discharge current sensor A3 determine whether the remaining energy in the intermediate DC circuit 5 is positive. When P 轮周 *η1 is greater than P 负载When the discharge current of the charging and discharging unit 7 collected by the discharge current sensor A3 is ≤0, it is determined that the intermediate DC circuit 5 has remaining braking energy to charge the power battery 11 first, and the allowable charging current value is I1 when it is converted into electric braking energy.

[0082] The power battery recharge control method for railway engineering vehicles also includes the following steps:

[0083] S106) When the intermediate DC voltage U0 of the intermediate DC circuit 5 exceeds U 开通 When the remaining energy of the electric braking exceeds the charging capacity of the power battery 11, the discharge function of the (DC / DC) chopper unit 14 is activated. The transmission control unit 4 controls the chopper unit 14 to dissipate the excess energy onto the braking resistor 15. 开通 This is the turn-on voltage of the intermediate DC circuit 5. When the intermediate DC voltage U0 of the intermediate DC circuit 5 ≤ U 关断 At that time, the discharge function of chopper unit 14 is turned off, U 关断 This is the turn-off voltage for the intermediate DC circuit 5.

[0084] In the description of this application, it should be noted that when an element is referred to as being "fixed to" or "set on" another element, it may be directly or indirectly set on another element; when an element is referred to as being "connected to" another element, it may be directly or indirectly connected to another element.

[0085] It should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0086] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" or "several" means two or more, unless otherwise explicitly specified.

[0087] It should be noted that the structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only used to complement the content disclosed in the specification for those skilled in the art to understand and read, and are not intended to limit the conditions under which this application can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and purposes that this application can produce, should still fall within the scope of the technical content disclosed in this application.

[0088] By implementing the technical solution of the power battery charging control system and method for railway engineering vehicles described in the specific embodiments of the present invention, the following technical effects can be achieved:

[0089] (1) The power battery energy feeding and charging control system and method for railway engineering vehicles described in the specific embodiments of the present invention, when the rail vehicle with power battery is working in electric braking mode, the electric braking energy is given priority to charge the power battery, which can improve the energy utilization rate, and the system structure is simple and the cost is low.

[0090] (2) The power battery energy feeding and charging control system and method for railway engineering vehicles described in the specific embodiments of the present invention can determine the energy and current flow direction of the system through data calculation and sensor sampling, which can recover braking energy to the maximum extent and does not require additional energy storage devices.

[0091] (3) The power battery energy feeding and charging control system and method for railway engineering vehicles described in the specific embodiments of the present invention adopts braking energy recovery discrimination calculation and power battery charging control. The power battery is both a provider of traction energy and a receiver of braking energy. It does not require the installation of supercapacitors, flywheels and other energy storage components, thus saving system costs to the maximum extent.

[0092] (4) The power battery energy feeding and charging control system and method for railway engineering vehicles described in the specific embodiments of the present invention can adaptively adjust the charging current of the power battery by calculating and comparing the energy of the intermediate DC circuit, and can maximize the recovery of wheel braking energy.

[0093] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0094] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make many possible variations and modifications to the technical solutions of the present invention using the methods and techniques disclosed above, or modify them into equivalent embodiments with equivalent changes, without departing from the spirit and technical essence of the present invention. Therefore, any simple modifications, equivalent substitutions, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall still fall within the protection scope of the technical solutions of the present invention.

Claims

1. A power battery recharge control system for railway engineering vehicles, characterized in that, include: The system includes a central control unit (1), a power battery management system (3), a transmission control unit (4), an intermediate DC circuit (5), a three-phase controllable unit (6), a charging and discharging unit (7), a traction inverter unit (8), an auxiliary inverter unit (9), a power battery (11), a traction motor (12), an auxiliary load (13), and a discharge current sensor (A3). The three-phase controllable unit (6), the charging and discharging unit (7), the traction inverter unit (8), and the auxiliary inverter unit (9) are all connected to the intermediate DC circuit (5). When in electric braking mode, the traction motor (12) acts as a generator to transfer the wheel braking energy. The wheel circumference braking energy is input to the intermediate DC circuit (5) through the traction inverter unit (8). The energy consumed by the intermediate DC circuit (5) and the auxiliary inverter unit (9) on the auxiliary load (13) is The central control unit (1) according to , The size and discharge current sensor (A3) are used to determine whether the device has entered the charging state. To improve the rectification efficiency of the traction inverter unit (8), To improve the inverter efficiency of the auxiliary inverter unit (9); when Greater than And the discharge current of the charging and discharging unit (7) collected by the discharge current sensor (A3) When it is determined that there is remaining braking energy, it is prioritized to charge the power battery (11), and the allowable charging current value is converted into electric braking energy. Combined with the allowable charging current value of the power battery output by the power battery management system (3), Calculate the target value of the charging current. The remaining braking energy is transmitted from the intermediate DC circuit (5) through the charging and discharging unit (7), and then through the transmission control unit (4) according to the target charging current value. The charging and discharging unit (7) controls the charging and discharging of the power battery (11); The allowable charging current value of the electric braking energy Calculate using the following formula: ； in, The intermediate DC voltage of the intermediate DC circuit (5); according to , The size and discharge current sensor (A3) are used to determine whether the remaining energy in the intermediate DC circuit (5) is positive; when Greater than And the discharge current of the charging and discharging unit (7) collected by the discharge current sensor (A3) When it is determined that there is remaining braking energy in the intermediate DC circuit (5), it is prioritized to charge the power battery (11), and the allowable charging current value is converted into electric braking energy. ; When the intermediate DC voltage of the intermediate DC circuit (5) When the remaining energy of electric braking exceeds the charging capacity of the power battery (11), the discharge function of the chopper unit (14) is activated, and the transmission control unit (4) controls the chopper unit (14) to dissipate the excess energy on the braking resistor (15). The turn-on voltage of the intermediate DC circuit (5); when the intermediate DC voltage of the intermediate DC circuit (5) is... At this time, the discharge function of the chopper unit (14) is turned off. The turn-off voltage of the intermediate DC circuit (5) is .

2. The power battery charging control system for railway engineering vehicles according to claim 1, characterized in that, The energy consumed on the auxiliary load (13) Calculate using the following formula: ； in, The effective value of the output phase voltage of the auxiliary inverter unit (9) is collected by the voltage sensor (V3). The effective value of the output phase current of the auxiliary inverter unit (9) is collected by the current sensor (A4).

3. The power battery charging control system for railway engineering vehicles according to claim 1 or 2, characterized in that: The system also includes a traction generator set control unit (2) and a traction generator set (10). The traction generator set (10), the three-phase controllable unit (6), and the intermediate DC circuit (5) are connected in sequence. The traction generator set control unit (2) is connected to the traction generator set (10). The electrical energy generated by the traction generator set (10) is rectified by the three-phase controllable unit (6) and output to the intermediate DC circuit (5). The traction generator set control unit (2) controls the traction generator set (10).

4. The power battery charging control system for railway engineering vehicles according to claim 3, characterized in that: The system also includes a chopper unit (14) and a braking resistor (15). The intermediate DC circuit (5), including the chopper unit (14) and the braking resistor (15), are connected in sequence. When the remaining energy of the electric braking exceeds the charging capacity of the power battery (11), the transmission control unit (4) controls the chopper unit (14) to consume the excess energy on the braking resistor (15).

5. A method for controlling the recharge of a power battery in a railway engineering vehicle, characterized in that, Includes the following steps: S101) In traction generator, power battery, or hybrid power mode, when in electric braking condition and operating normally, calculate the energy consumed on the auxiliary load (13). ; S102) Based on the energy consumed on the auxiliary load (13) Wheel circumferential braking energy The discharge current of the charging and discharging unit (7) is used to determine whether the remaining energy of the intermediate DC circuit (5) is positive. If it is, continue to execute step S103; otherwise, jump to step S101. S103) Calculate the allowable charging current value for electric braking energy. ; S104) Based on the allowable charging current value of electric braking energy And in combination with the allowable charging current value of the power battery Calculate the target value of the charging current. ; S105) According to the target value of charging current The charging and discharging unit (7) controls the charging and discharging of the power battery (11); In step S103), the allowable charging current value of the electric braking energy is... Calculate using the following formula: ； in, For wheel braking energy, To improve the rectification efficiency of the traction inverter unit (8), To dissipate the energy on the auxiliary load (13), To improve the inverter efficiency of the inverter unit (9), The intermediate DC voltage of the intermediate DC circuit (5); Step S102) further includes: according to , The size and discharge current sensor (A3) are used to determine whether the remaining energy in the intermediate DC circuit (5) is positive; when Greater than And the discharge current of the charging and discharging unit (7) collected by the discharge current sensor (A3) When it is determined that there is remaining braking energy in the intermediate DC circuit (5), it is prioritized to charge the power battery (11), and the allowable charging current value is converted into electric braking energy. ; The method further includes the following steps: S106) When the intermediate DC voltage of the intermediate DC circuit (5) When the remaining energy of electric braking exceeds the charging capacity of the power battery (11), the discharge function of the chopper unit (14) is activated, and the transmission control unit (4) controls the chopper unit (14) to dissipate the excess energy on the braking resistor (15). The turn-on voltage of the intermediate DC circuit (5); when the intermediate DC voltage of the intermediate DC circuit (5) is... At this time, the discharge function of the chopper unit (14) is turned off. The turn-off voltage of the intermediate DC circuit (5) is .

6. The power battery recharge control method for railway engineering vehicles according to claim 5, characterized in that: In step S101), the energy consumed on the auxiliary load (13) Calculate using the following formula: ； in, The effective value of the output phase voltage of the auxiliary inverter unit (9) is collected by the voltage sensor (V3). The effective value of the output phase current of the auxiliary inverter unit (9) is collected by the current sensor (A4).

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