A hybrid electric system and control method for rail transit engineering vehicles

Abstract

This invention relates to the field of rail transit engineering vehicle technology, specifically to a hybrid electric power system and control method for rail transit engineering vehicles. The system includes an internal combustion engine unit, a power generation unit, a battery storage unit, a catenary power supply unit, a traction drive unit, a work load unit, and a power management control unit. The power management control unit is used for unified scheduling and coordinated control of multiple energy sources. During the operation of the engineering vehicle, based on the power supply status of the catenary line, the internal combustion engine power generation status, the environment of the engineering vehicle, the current power demand of the engineering vehicle, and the state of charge of the battery pack, it automatically selects the current power supply mode of the engineering vehicle to achieve stable power supply for traction operation and work load. This invention, through multi-energy coupling of oil and electricity and power management control methods, improves the adaptability of rail transit engineering vehicles under complex working conditions, reduces fuel consumption and noise emissions, and enhances the operational stability and economy of the engineering vehicle.

Description

Technical Field

[0001] This invention belongs to the field of rail transit engineering equipment technology, specifically relating to a hybrid electric power system and its control method for use in rail engineering vehicles. Background Technology

[0002] Urban rail transit engineering vehicles are widely used in scenarios such as line maintenance, emergency rescue, and engineering construction. Existing urban rail transit engineering vehicles mainly use hydraulic transmission internal combustion engines as their power source, which has the advantages of stable power and high reliability. However, they also have problems such as high noise, high exhaust emissions, and harsh operating environment when operating in tunnel sections.

[0003] In recent years, some rail transit equipment manufacturers have begun to develop battery-powered engineering vehicles that use batteries as a power source. However, these vehicles are limited by battery capacity, resulting in limited range and insufficient reliability in long-term construction or emergency rescue scenarios.

[0004] In extreme rain and snow, icing of the overhead contact line, power outages for overhead contact line maintenance, or nighttime maintenance without power, the power supply to the overhead contact line may be limited. Engineering vehicles relying solely on overhead contact line power or battery power alone cannot meet the demands of long-term continuous operation. In current urban rail transit operations, after passenger service on the main line ends, the operating company's maintenance department needs to conduct maintenance work on tunnels and the overhead contact line under power-deprived conditions. Under overhead contact line power outages, the range of battery-powered engineering vehicles is limited. Currently, there is a lack of a power solution for rail engineering vehicles that can balance the stability of internal combustion engines with low fuel consumption, low fuel costs, low emissions, and low noise operation, especially a hybrid electric system designed specifically for the operating conditions of rail transit engineering vehicles.

[0005] The purpose of this invention is to provide a hybrid electric power system and control method for rail transit engineering vehicles. By coordinating the operation of an internal combustion engine, a generator, and a battery, the system enables the engineering vehicle to operate efficiently, stably, and with low emissions under different working conditions, reducing fuel consumption and operating costs for urban rail transit operating companies, and improving the reliability and overall performance of the engineering vehicle. Furthermore, based on the power supply status of the overhead contact line, the internal combustion engine power generation status, the environment in which the engineering vehicle is located, the current power demand of the engineering vehicle, and the state of charge of the battery pack, the system automatically selects the current power supply mode for the engineering vehicle, thereby reducing fuel consumption and operating costs under the internal combustion engine power generation mode. Summary of the Invention

[0006] To overcome the shortcomings of existing technologies, the purpose of this invention is to provide a hybrid electric power system and control method suitable for urban rail transit engineering vehicles. By coordinating the operation of an internal combustion engine, a generator, and a battery pack, the system enables the engineering vehicle to operate efficiently, stably, and with low emissions under different working conditions, thereby improving the overall performance and reliability of the engineering vehicle. Furthermore, based on the power supply status of the overhead contact line, the internal combustion engine power generation status, the environment in which the engineering vehicle is located, the current power demand of the engineering vehicle, and the state of charge of the battery pack, the system automatically selects the current power supply mode for the engineering vehicle, reducing fuel consumption and operating costs under the internal combustion engine power generation mode.

[0007] This invention provides a hybrid electric power system for rail transit engineering vehicles, comprising: Internal combustion power unit: used to provide stable power output for engineering vehicles under heavy load conditions, long-term operation and emergency rescue scenarios; the internal combustion engine does not directly drive the bogie wheels, but supplies power to the electric drive system or charges the battery pack through the power generation unit, providing stability for system operation.

[0008] Power generation unit: Connected to the internal combustion power unit, used to convert internal combustion power into electrical energy.

[0009] Battery storage unit: Used to store electrical energy generated by the power generation unit or the overhead contact line power supply unit, and to supply power to the traction system during pure electric operation or auxiliary power output. The battery storage unit is used for at least: pure electric operation in tunnels and low-noise working areas; providing instantaneous high-power output for the traction motor; and balancing power fluctuations between different energy sources.

[0010] Traction drive unit: includes traction motor and its controller, used to convert electrical energy into mechanical energy to drive the operation of the engineering vehicle.

[0011] Work load unit: Used to consume electrical energy and perform maintenance, lighting and other work functions of engineering vehicles.

[0012] The overhead contact line power collection unit includes a pantograph device and a power conversion module. It is used to directly collect external power in line sections where an overhead contact line is available, to charge the battery banks in the battery storage unit, or to power the traction system. Depending on the operating status, it can: directly power the traction motor; replenish the battery banks in the battery storage unit; or power the working load of engineering vehicles.

[0013] Power management control unit: used to automatically select the current power supply mode of the engineering vehicle based on the power supply status of the overhead contact line, the internal combustion generator status, the environment in which the engineering vehicle is located, the current power demand of the engineering vehicle, and the state of charge of the battery pack.

[0014] Current energy supply modes include overhead contact line energy supply mode, independent battery energy supply mode, internal combustion engine power generation energy supply mode, multi-energy combined energy supply mode, reduced power operation mode, or safe shutdown mode. Among them, the contact network power supply mode refers to the power supply unit of the contact network to the traction drive unit and the engineering load when the contact network is available and the pantograph is allowed to draw power; the battery independent power supply mode refers to the power supply unit of the battery pack energy storage unit to the engineering vehicle at night, in tunnels, or in low-noise or low-emission restricted areas; the internal combustion engine power generation mode refers to the power generation unit driven by the internal combustion power unit to output electrical energy to power the traction drive unit and the engineering load of the engineering vehicle; the multi-energy combined power supply mode refers to the power supply branch of the internal combustion power unit and the power generation unit, or the contact network power supply branch composed of the contact network power draw unit, providing basic power, and the battery pack energy storage unit providing compensation power; the power reduction operation mode or safe parking mode refers to the power management control unit limiting the output power of the traction drive unit when the available power supply capacity is insufficient or the key power supply unit is abnormal, so that the engineering vehicle runs to a safe area in a low-speed, low-power state; when the remaining power supply capacity is insufficient to maintain low-speed operation, the traction drive unit is controlled to cut off the traction output, and the braking system is used to stop the engineering vehicle safely.

[0015] During nighttime maintenance or tunnel operations, when the overhead contact line is unavailable or pantograph power extraction is not permitted, and the state of charge (SOC) of the battery pack is not lower than a preset low charge threshold, the power management control unit controls the engineering vehicle to operate in an independent battery power supply mode. During emergency repairs and long-distance traction operations, the power management control unit determines the basic power supply branch based on the availability of the overhead contact line power supply branch and the internal combustion engine power supply branch, and the battery pack energy storage unit provides compensation power.

[0016] This invention provides a control method for a hybrid electric system for rail transit engineering vehicles, comprising: S1: Collect engineering vehicle operating status information: Collect operational status information of engineering vehicles. This information includes the overhead contact line power supply status, pantograph status, battery pack charge status, internal combustion engine unit operation status, generator unit operation status, engineering vehicle speed, traction power requirements, engineering work load power, track gradient, work area type, and noise restrictions.

[0017] S2: Calculate the current total power demand of the engineering vehicle: The method for determining the current total power demand of engineering vehicles is as follows: (1) in, This represents the current total power requirement of the engineering vehicle. Power required for traction operation, This refers to the power requirements of the engineering work load. The engineering work load power includes the power requirements of lighting, air compressors, hydraulic equipment, maintenance equipment, and other vehicle-mounted work equipment. S3: Determine the current status of the engineering vehicle The power management and control unit determines the overhead contact line status value based on the operating status information of the engineering vehicle. Battery status values Internal combustion power generation available state value Environmental limitation status values and high power demand state value .

[0018] Among them, the contact wire status value Used to characterize whether the overhead contact line is available and whether power can be drawn from the pantograph, its value is: (2) Battery status values Used to characterize the charge of a battery pack Whether it is not lower than the preset low battery threshold, the value of which is: (3) Internal combustion power generation available state value This value is used to characterize whether both the internal combustion power unit and the power generation unit are in a usable state. (4) Environmental Limitation Status Values This value is used to characterize whether the engineering vehicle is currently in a nighttime, tunnel, low-noise, or low-emission restricted area, and its values ​​are: (5) High power demand state value This value is used to characterize whether the engineering vehicle is currently in a high-power demand state, such as starting, climbing, heavy-load traction, sudden load change, or emergency traction. (6) S4: Select the current power supply mode based on the state variables. The power management control unit determines the current power supply mode based on the current status of the engineering vehicle: (7) in, For the currently selected energy supply mode, For overhead contact line power supply mode, This is a battery-independent power supply mode. The power generation mode is based on internal combustion engines. It is a multi-energy combined power supply mode. This is either a reduced power operation mode or a safe shutdown mode.

[0019] The specific control logic is as follows: when the power demand is high, the multi-energy combined power supply mode is selected first; when the overhead contact line is available and there is no sudden high power change, the overhead contact line power supply mode is selected first; when the overhead contact line is unavailable, the environment is restricted, and the battery power meets the requirements, the battery independent power supply mode is selected; when the overhead contact line is unavailable and the battery power is insufficient or not in a restricted environment, the internal combustion engine power generation mode is selected; when the available power supply capacity is insufficient or the key power supply unit is abnormal, the power reduction operation mode or the safety shutdown mode is entered.

[0020] When the engineering vehicle is in the state of starting, climbing, heavy-load traction, sudden load change or emergency traction, the battery pack charge SOC is not lower than the preset low charge threshold, and at least one of the overhead contact line power supply branch or internal combustion power generation power supply branch is available, the power management control unit selects the multi-energy combined power supply mode. When the engineering vehicle is not in the state of starting, climbing, heavy-load traction, sudden load change or emergency traction, and the contact network is available and allows the pantograph to be raised to draw power, the power management control unit prioritizes the contact network power supply mode, and charges the battery pack in the battery pack energy storage unit when the battery pack's SOC is lower than the preset low charge threshold. When the overhead contact line is unavailable or pantograph raising is not permitted, and the engineering vehicle is in a nighttime, tunnel, low-noise or low-emission restricted area, and the battery pack SOC is not lower than the low charge threshold, the power management control unit selects the battery independent power supply mode. When the engineering vehicle is not in the starting, climbing, heavy-load towing, load change, or emergency towing state; and the overhead contact line is unavailable or pantograph raising is not allowed; and both the internal combustion power unit and the generator unit are available; and at least one of the following conditions is met, the power management control unit selects the internal combustion engine generator power supply mode: (1) The state of charge (SOC) of the battery pack is less than the low charge threshold; (2) The engineering vehicle was not in a nighttime, tunnel, or low-noise or low-emission restricted area; When none of the above power supply conditions are met, the power management control unit selects either the reduced power operation mode or the safe shutdown mode.

[0021] Preferably, when none of the above-mentioned power supply conditions are met, it may further include: when the engineering vehicle is in a starting, climbing, heavy-load traction, load change, or emergency traction state (high power demand state value). The battery pack's state of charge (SOC) is lower than the preset low charge threshold (battery availability value). When the power management control unit is activated, it does not directly select the power reduction operation mode or the safe shutdown mode. Instead, it first determines whether the output power of the overhead contact line power supply branch or the internal combustion power generation power supply branch can meet the current total power demand. If it can, it selects the corresponding single power supply mode; if it cannot, it enters the power reduction operation mode or the safe shutdown mode.

[0022] S5: Execute the corresponding power supply control When the power supply mode is determined to be catenary power supply mode, the catenary power take-off unit supplies power to the traction drive unit and engineering operation load, and charges the battery pack energy storage unit when the battery pack charge state (SOC) is lower than the preset low charge threshold.

[0023] When the battery is set to independent power supply mode, the battery pack energy storage unit supplies power to the traction drive unit and engineering work load, and controls the internal combustion power unit to stop running or remain in standby mode.

[0024] When the internal combustion engine is selected as the power supply mode, the internal combustion power unit drives the power generation unit to output electrical energy, which serves as the power supply branch for the internal combustion power generation to supply power to the traction drive unit and engineering work load, and charges the battery pack energy storage unit according to the state of charge of the battery pack.

[0025] When the multi-energy combined power supply mode is determined, the basic power is provided by the internal combustion power generation branch consisting of the internal combustion power unit and the power generation unit, or by the contact network power supply branch consisting of the contact network power taking unit, and the compensation power is provided by the battery pack energy storage unit.

[0026] When the power reduction operation mode or safe parking mode is determined, the power management control unit limits the output power of the traction drive unit, so that the engineering vehicle runs to a safe area at low speed and low power. When the remaining power supply capacity is insufficient to maintain low speed operation, the traction drive unit is controlled to cut off the traction output and cooperate with the braking system to stop the engineering vehicle safely.

[0027] S6: Determining battery compensation power under multi-energy combined power supply mode When entering the multi-energy combined power supply mode, the output compensation power of the battery pack is determined according to the following formula: (8) in, Provides compensation power to the battery pack. The maximum allowable discharge power of the battery pack. This represents the current total power requirement of the engineering vehicle. This refers to the base output power currently available from the basic power supply branch. The basic power supply branch includes internal combustion power generation power supply branches, which include internal combustion power units and power generation units, or overhead contact line power supply branches, which include overhead contact line power collection units.

[0028] When a multi-energy combined power supply mode is selected, the basic power supply branch provides the base power, and the battery storage unit provides the compensation power. The base power supply branch currently provides the base output power... Not less than the current total power requirement of the engineering vehicle At that time, the battery pack energy storage unit does not perform power compensation; when the basic power supply branch can currently provide basic output power... Below the current total power demand of engineering vehicles When the battery pack energy storage unit compensates for the difference, the compensation power shall not exceed the maximum allowable discharge power of the battery pack.

[0029] S7: Abnormal Power Supply Handling When an abnormality is detected in the overhead contact line power supply unit, internal combustion power unit, power generation unit, or battery energy storage unit, the power management control unit redetermines the power supply mode based on the remaining available power supply units; when the remaining power supply capacity cannot meet the current total power demand of the engineering vehicle, the control unit controls the engineering vehicle to enter a power reduction operation mode or a safe parking mode.

[0030] Compared with the prior art, the beneficial effects of the present invention are: 1. By working in concert with the internal combustion power unit, power generation unit, battery energy storage unit, and overhead contact line power extraction unit, the engineering vehicle can achieve efficient, stable, and low-emission operation under different working conditions, thereby improving the overall performance and reliability of the engineering vehicle. 2. By setting the contact network status value, battery availability status value, internal combustion generator availability status value, environmental restriction status value, and high power demand status value, a mode selection rule is formed, enabling the engineering vehicle to automatically select the current power supply mode according to the actual working conditions, ensuring the flexibility and adaptability of the engineering vehicle's power supply mode selection; 3. During nighttime tunnel maintenance and in areas with low noise or low emission restrictions, the independent battery power supply mode should be given priority to reduce noise and exhaust emissions. 4. During startup, hill climbing, heavy-load traction, sudden load changes, or emergency traction, the peak power response capability of the engineering vehicle is improved through multi-energy combined power supply mode and battery compensation power calculation. 5. When a single power supply unit malfunctions, the power management control unit can redetermine the power supply mode based on the remaining available energy, and enter a reduced power operation mode or a safe shutdown mode when the power supply is insufficient, thereby improving the safety and reliability of the engineering vehicle operation. Attached Figure Description

[0031] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute an undue limitation of this application.

[0032] Figure 1 This is a schematic diagram of the overall structure of a hybrid electric power system for rail transit engineering vehicles according to the present invention; Figure 2 A schematic diagram of the power supply mode selection and control process for the power management control unit; Figure 3 This is a schematic flowchart of a hybrid power control method for rail transit engineering vehicles according to the present invention. Figure 4 A schematic diagram illustrating the process of selecting the energy supply mode under nighttime tunnel maintenance conditions; Figure 5 This is a schematic diagram of the power distribution process under a multi-energy combined power supply mode. Detailed Implementation

[0033] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0034] 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 exemplary embodiments according to this application. 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.

[0035] As described in the background section, there are shortcomings in the existing technology. In order to solve the above-mentioned technical problems, this solution is proposed.

[0036] like Figure 1 As shown, Figure 1 The present invention illustrates the overall structure of a hybrid electric power system for rail transit engineering vehicles, comprising: Internal combustion power unit: used to provide stable power output for engineering vehicles under heavy load conditions, long-term operation and emergency rescue scenarios; the internal combustion engine does not directly drive the bogie wheels, but supplies power to the electric drive system or charges the battery pack through the power generation unit, providing stability for system operation.

[0037] Power generation unit: Connected to the internal combustion power unit, used to convert internal combustion power into electrical energy.

[0038] Battery storage unit: Used to store electrical energy generated by the power generation unit or the overhead contact line power supply unit, and to supply power to the traction system during pure electric operation or auxiliary power output. The battery storage unit is used for at least: pure electric operation in tunnels and low-noise working areas; providing instantaneous high-power output for the traction motor; and balancing power fluctuations between different energy sources.

[0039] Traction drive unit: includes traction motor and its controller, used to convert electrical energy into mechanical energy to drive the operation of the engineering vehicle.

[0040] Work load unit: Used to consume electrical energy and perform maintenance, lighting and other work functions of engineering vehicles.

[0041] The overhead contact line power collection unit includes a pantograph and a power conversion module. It is used to directly collect external power in line sections where an overhead contact line is available, to charge the battery storage unit or supply power to the traction system. Depending on the operating status, it can: directly supply power to the traction motor; replenish the battery storage unit; or supply power to the working load of engineering vehicles.

[0042] Power management control unit: used to automatically select the current power supply mode of the engineering vehicle based on the power supply status of the overhead contact line, the internal combustion generator status, the environment in which the engineering vehicle is located, the current power demand of the engineering vehicle, and the state of charge of the battery pack.

[0043] Current energy supply modes include overhead contact line energy supply mode, independent battery energy supply mode, internal combustion engine power generation energy supply mode, multi-energy combined energy supply mode, reduced power operation mode, or safe shutdown mode. Among them, the contact network power supply mode refers to the power supply unit of the contact network to the traction drive unit and the engineering load when the contact network is available and the pantograph is allowed to draw power; the battery independent power supply mode refers to the power supply unit of the battery pack energy storage unit to the engineering vehicle at night, in tunnels, or in low-noise or low-emission restricted areas; the internal combustion engine power generation mode refers to the power generation unit driven by the internal combustion power unit to output electrical energy to power the traction drive unit and the engineering load of the engineering vehicle; the multi-energy combined power supply mode refers to the power supply branch of the internal combustion power unit and the power generation unit, or the contact network power supply branch composed of the contact network power draw unit, providing basic power, and the battery pack energy storage unit providing compensation power; the power reduction operation mode or safe parking mode refers to the power management control unit limiting the output power of the traction drive unit when the available power supply capacity is insufficient or the key power supply unit is abnormal, so that the engineering vehicle runs to a safe area in a low-speed, low-power state; when the remaining power supply capacity is insufficient to maintain low-speed operation, the traction drive unit is controlled to cut off the traction output, and the braking system is used to stop the engineering vehicle safely.

[0044] The key energy supply unit can be one or more of the following: overhead contact line power supply unit, internal combustion power unit, power generation unit, or battery storage unit.

[0045] During nighttime maintenance or tunnel operations, when the overhead contact line is unavailable or pantograph power extraction is not permitted, and the state of charge (SOC) of the battery pack is not lower than a preset low charge threshold, the power management control unit controls the engineering vehicle to operate in an independent battery power supply mode. During emergency repairs and long-distance traction operations, the power management control unit determines the basic power supply branch based on the availability of the overhead contact line power supply branch and the internal combustion engine power supply branch, and the battery pack energy storage unit provides compensation power.

[0046] like Figures 2-3 As shown, Figure 2 This paper illustrates a schematic diagram of the selection process of the main energy supply mode of the power management control unit under normal operating conditions in a control method for a hybrid electric vehicle for rail transit engineering vehicles. First, the current operating condition type and operating status information (energy availability) of the engineering vehicle are obtained. Based on the current status of the engineering vehicle, the energy supply mode is determined. In case of abnormality, the power reduction operation mode or the safe stop mode can be entered. Traction and working power are allocated based on the energy supply mode, and the operating status is continuously monitored and adjusted. Figure 3 A flowchart illustrating a control method for a hybrid electric system used in rail transit engineering vehicles is shown. After executing the corresponding power supply control, the power management control unit continuously monitors the operating status of the engineering vehicle and the status of each power supply unit. When an abnormality in a power supply unit or insufficient power supply capacity is detected, the current power supply mode is redefined. If the remaining power supply capacity is insufficient, the engineering vehicle is controlled to enter a reduced-power operation mode or a safe stop mode. If the work is not yet completed, the system returns to the operating status information acquisition step. When the work is completed, the system exits the current operation mode. Specifically, this includes: S1: Collect engineering vehicle operating status information: Collect operational status information of engineering vehicles. This information includes the overhead contact line power supply status, pantograph status, battery pack charge status, internal combustion engine unit operation status, generator unit operation status, engineering vehicle speed, traction power requirements, engineering work load power, track gradient, work area type, and noise restrictions.

[0047] S2: Calculate the current total power demand of the engineering vehicle: The method for determining the total power demand of the engineering vehicle is shown in formula (1):

[0048] Among them, according to the power required for traction operation Engineering operation load power Determine the current total power requirement of the engineering vehicles. The power requirements for engineering work loads include those for lighting, air compressors, hydraulic equipment, maintenance equipment, and other vehicle-mounted work equipment.

[0049] S3: Determine the current status of the engineering vehicle The power management and control unit determines the overhead contact line status value based on the operating status information of the engineering vehicle. Battery status values Internal combustion power generation available state value Environmental limitation status values and high power demand state value .

[0050] Among them, the contact wire status value The value used to characterize whether the overhead contact line is available and whether it is permissible to draw power from the pantograph is as shown in formula (2):

[0051] Battery status values Used to characterize the charge of a battery pack Whether it is not lower than the preset low battery threshold, the value of which is shown in formula (3):

[0052] Internal combustion power generation available state value The value used to characterize whether both the internal combustion power unit and the power generation unit are in a usable state is shown in formula (4):

[0053] Environmental Limitation Status Values The value used to characterize whether the engineering vehicle is currently in a nighttime, tunnel, low-noise, or low-emission restricted area is shown in formula (5):

[0054] High power demand state value The value used to characterize whether the engineering vehicle is currently in a high-power demand state such as starting, climbing, heavy-load traction, sudden load change, or emergency traction is shown in formula (6):

[0055] The values ​​of each state variable are shown in Table 1 below: Table 1: Illustrated Table of Meanings of State Variable Values

[0056] Among them, the preset thresholds for low power consumption, low noise, low emissions, heavy traction, and sudden load changes can be flexibly set or determined according to the actual operating conditions.

[0057] S4: Select the current power supply mode based on the state variables. The power management control unit determines the current power supply mode based on the current state of the engineering vehicle, as shown in formula (7):

[0058] in, For the currently selected energy supply mode, For overhead contact line power supply mode, This is a battery-independent power supply mode. The power generation mode is based on internal combustion engines. It is a multi-energy combined power supply mode. This is either a reduced power operation mode or a safe shutdown mode.

[0059] The corresponding relationships of the power supply mode selection rules are shown in Table 2 below, where number 5 is a supplementary selection rule for formula (7): Table 2: Correspondence Table of Mode Selection Functions

[0060] The specific control logic is as follows: when the power demand is high, the multi-energy combined power supply mode is selected first; when the overhead contact line is available and there is no sudden high power change, the overhead contact line power supply mode is selected first; when the overhead contact line is unavailable, the environment is restricted, and the battery power meets the requirements, the battery independent power supply mode is selected; when the overhead contact line is unavailable, the battery power is insufficient, or the environment is not restricted, the internal combustion engine power generation mode is selected; when the power supply capacity is insufficient or the key power supply unit is abnormal, the power reduction operation mode or the safety shutdown mode is entered.

[0061] When the engineering vehicle is in the state of starting, climbing, heavy-load traction, sudden load change or emergency traction, the battery pack charge SOC is not lower than the preset low charge threshold, and at least one of the overhead contact line power supply branch or internal combustion power generation power supply branch is available, the power management control unit selects the multi-energy combined power supply mode. When the engineering vehicle is not in the state of starting, climbing, heavy-load traction, sudden load change or emergency traction, and the contact network is available and allows the pantograph to be raised to draw power, the power management control unit prioritizes the contact network power supply mode, and charges the battery pack in the battery pack energy storage unit when the battery pack's SOC is lower than the preset low charge threshold. When the overhead contact line is unavailable or pantograph raising is not permitted, and the engineering vehicle is in a nighttime, tunnel, low-noise or low-emission restricted area, and the battery pack SOC is not lower than the low charge threshold, the power management control unit selects the battery independent power supply mode. When the engineering vehicle is not in the starting, climbing, heavy-load towing, load change, or emergency towing state; and the overhead contact line is unavailable or pantograph raising is not allowed; and both the internal combustion power unit and the generator unit are available; and at least one of the following conditions is met, the power management control unit selects the internal combustion engine generator power supply mode: (1) The state of charge (SOC) of the battery pack is less than the low charge threshold; (2) The engineering vehicle was not in a nighttime, tunnel, or low-noise or low-emission restricted area; When none of the above power supply conditions are met, the power management control unit selects either the reduced power operation mode or the safe shutdown mode.

[0062] Preferably, when none of the above-mentioned power supply conditions are met, it may further include: when the engineering vehicle is in a starting, climbing, heavy-load traction, load change, or emergency traction state (high power demand state value). The battery pack's state of charge (SOC) is lower than the preset low charge threshold (battery availability value). When the power management control unit is activated, it does not directly select the power reduction operation mode or the safe shutdown mode. Instead, it first determines whether the output power of the overhead contact line power supply branch or the internal combustion power generation power supply branch can meet the current total power demand. If it can, it selects the corresponding single power supply mode; if it cannot, it enters the power reduction operation mode or the safe shutdown mode.

[0063] S5: Execute the corresponding power supply control When the power supply mode is determined to be catenary power supply mode, the catenary power take-off unit supplies power to the traction drive unit and engineering operation load, and charges the battery pack energy storage unit when the battery pack charge state (SOC) is lower than the preset low charge threshold.

[0064] When the battery is set to independent power supply mode, the battery pack energy storage unit supplies power to the traction drive unit and engineering work load, and controls the internal combustion power unit to stop running or remain in standby mode.

[0065] When the internal combustion engine is selected as the power generation mode, the internal combustion power unit drives the power generation unit to output electrical energy to power the traction drive unit and engineering work load, and charges the battery pack energy storage unit according to the battery pack charge.

[0066] When the multi-energy combined power supply mode is determined, the basic power is provided by the internal combustion power generation branch consisting of the internal combustion power unit and the power generation unit, or by the contact network power supply branch consisting of the contact network power taking unit, and the compensation power is provided by the battery pack energy storage unit.

[0067] When the power reduction operation mode or safe parking mode is determined, the power management control unit limits the output power of the traction drive unit, so that the engineering vehicle runs to a safe area at low speed and low power. When the remaining power supply capacity is insufficient to maintain low speed operation, the traction drive unit is controlled to cut off the traction output and cooperate with the braking system to stop the engineering vehicle safely.

[0068] The operating conditions and control logic corresponding to different power supply modes are shown in Table 3 below: Table 3: Mode Selection Rules Table

[0069] S6: Determining battery compensation power under multi-energy combined power supply mode When entering the multi-energy combined power supply mode, the battery pack output compensation power is as shown in formula (8):

[0070] When a multi-energy combined power supply mode is selected, the basic power supply branch provides the base power, and the battery storage unit provides the compensation power. The base power supply branch currently provides the base output power... Not less than the current total power requirement of the engineering vehicle At that time, the battery pack energy storage unit does not perform power compensation; when the basic power supply branch can currently provide basic output power... Below the current total power demand of engineering vehicles When the battery pack energy storage unit compensates for the difference, the compensation power shall not exceed the maximum allowable discharge power of the battery pack.

[0071] S7: Abnormal Power Supply Handling When an abnormality is detected in the overhead contact line power supply unit, internal combustion power unit, power generation unit, or battery energy storage unit, the power management control unit redetermines the power supply mode based on the remaining available power supply units; when the remaining power supply capacity cannot meet the current total power demand of the engineering vehicle, the control unit controls the engineering vehicle to enter a reduced power operation state or a safe parking state.

[0072] This invention provides a hybrid electric power system and method for rail transit engineering vehicles. By coordinating the operation of an internal combustion engine power unit, a power generation unit, a battery energy storage unit, and a catenary power extraction unit, the system enables the engineering vehicle to operate efficiently, stably, and with low emissions under different working conditions, thereby improving the overall performance and reliability of the engineering vehicle. By setting catenary status values, battery availability values, internal combustion engine power generation availability values, environmental limitation values, and high power demand values, a mode selection rule is formed, enabling the engineering vehicle to automatically select the current power supply mode according to the actual working conditions, ensuring the flexibility and adaptability of the engineering vehicle's power supply mode selection.

[0073] To more clearly illustrate the technical solution of the present invention, the following different embodiments are provided for detailed explanation: Example 1: Nighttime Tunnel Maintenance Operations In this embodiment, the hybrid electric power system of the rail transit engineering vehicle can be applied to nighttime tunnel maintenance operations in urban rail transit.

[0074] Nighttime tunnel maintenance is usually carried out after trains have stopped running. The work time is concentrated and the work environment is closed. It places high demands on the noise, exhaust emissions and operational safety of the engineering vehicles, while also requiring a continuous and stable power supply for various maintenance equipment.

[0075] Before the engineering vehicle enters the tunnel section, the power management control unit automatically identifies the upcoming tunnel maintenance conditions based on line information and the operation plan, and first determines whether the overhead contact line is available and allows for pantograph power extraction. If the overhead contact line is available and pantograph power extraction is allowed, the overhead contact line power supply mode is selected, and the battery pack's state of charge (SOC) is used to determine whether to replenish the battery pack's energy storage unit. If the overhead contact line is unavailable or pantograph power extraction is not allowed, the system further assesses the battery pack's SOC and the availability of the internal combustion engine power unit and generator unit, and accordingly selects the battery independent power supply mode, internal combustion engine generator power supply mode, reduced power operation mode, or safe shutdown mode.

[0076] Environmental limiting conditions when engineering vehicles are operating at low speeds and performing maintenance work in tunnels at night. If the overhead contact line is unavailable, that is Furthermore, the state of charge of the battery pack is not lower than the preset low charge threshold, i.e. Meanwhile, the engineering vehicle is not in a state of starting, climbing, heavy-load traction, or sudden load change, i.e. According to the mode selection function, the current power supply mode is the battery independent power supply mode. At this time, the internal combustion power unit stops running or remains in standby (off state), and the battery pack energy storage unit supplies power to the traction drive unit and engineering work load. The traction drive of the engineering vehicle is mainly powered by the battery pack energy storage unit, thereby achieving low noise and zero exhaust emission operation.

[0077] That is, Figure 4 As shown, Figure 4 The process of selecting the power supply mode during nighttime tunnel maintenance is illustrated: First, it is determined whether the tunnel section has the conditions for contact network power supply, i.e., the contact network is available and pantograph raising is permitted. In this case, the contact network power supply mode is adopted, and the system determines whether to replenish the battery pack through the contact network power extraction unit based on the battery pack's state of charge (SOC). If the tunnel section does not have the conditions for contact network power supply, i.e., the contact network is unavailable or pantograph raising is not permitted, it is determined whether the battery pack's SOC is not lower than a preset low charge threshold. If the battery pack's SOC is not lower than the preset low charge threshold, the battery pack's energy storage unit supplies power to the traction motor of the engineering vehicle and the engineering load for low-noise operation. If the battery pack's SOC is lower than the preset low charge threshold, the internal combustion power unit and the generator unit are activated to provide power to the battery-powered engineering vehicle, while simultaneously charging the battery pack's energy storage unit to store charge. Finally, after the operation is completed, the system exits the operation mode.

[0078] Generally, when the maintenance department of a city subway operating company performs tunnel maintenance work, it will shut off the power to the overhead contact line. At this time, the power management control unit monitors the state of charge of the battery pack in real time. When the charge drops to a preset low charge threshold, the internal combustion engine is automatically started. The internal combustion power unit and the generator unit are connected together to perform the power generation task and charge the battery pack. In this way, concerns about the range of the engineering vehicle are reduced, and it can operate for a longer period of time.

[0079] Through the above control methods, the engineering vehicles can operate with low noise and zero or low emissions during nighttime tunnel maintenance, while ensuring the continuity of maintenance operations and the stability of power supply.

[0080] Example 2: Emergency Repair Long-Distance Traction Condition In this embodiment, the hybrid electric power system of the rail transit engineering vehicle can be applied to emergency repairs and long-distance traction operations in the event of sudden failures in urban rail transit.

[0081] When a sudden equipment failure occurs on the line or when engineering vehicles need to undertake emergency repair tasks, the engineering vehicles may need to run long distances in sections without overhead contact lines or with unstable power supply from the overhead contact lines, and undertake heavy-load traction or continuous operation tasks.

[0082] After receiving an emergency task, the power management control unit automatically enters emergency operation mode according to the task type: that is, when the engineering vehicle is in emergency repair, long-distance towing, heavy-load towing, or slope operation, the power demand value is high. The state of charge of the battery pack is not lower than the preset low charge threshold, i.e., the battery's usable state value. If at least one of the overhead contact line power supply branch or the internal combustion power generation power supply branch (internal combustion power unit + power generation unit) is available, that is... According to the mode selection function, the current energy supply mode is a multi-energy combined energy supply mode. .

[0083] Start the internal combustion power unit and the power generation unit to operate them under reliable conditions; simultaneously charge the battery pack energy storage unit to maintain the battery pack's state of charge within the preset target range, and determine the output power within the allowable power range of the traction drive unit according to the traction load requirements.

[0084] During emergency repairs and long-distance towing, the internal combustion engine power unit and generator unit serve as the primary energy sources, continuously supplying power to the traction drive unit of the engineering vehicle. The battery pack energy storage unit is used to compensate for instantaneous high power demands, such as starting, climbing hills, or towing heavy-load equipment. The power management control unit dynamically adjusts the output power of the internal combustion engine and the discharge ratio of the battery to avoid long-term operation under load from a single energy source. When the engineering vehicle reaches a section with overhead contact line power supply, the system automatically switches to the overhead contact line priority power supply mode to reduce fuel consumption and quickly replenish the battery pack. During operation, if an abnormality is detected in the internal combustion engine generator unit or insufficient fuel, the power management control unit can switch to the battery power supply mode within a short time to ensure that the engineering vehicle has the ability to safely stop or continue short-distance operation.

[0085] Among them, such as Figure 5 As shown, Figure 5 This demonstrates that during the multi-energy combined power supply allocation process, the power management control unit continuously monitors the battery pack's state of charge, the operating status of the basic power supply branch, and the current total power demand of the engineering vehicle. When the conditions for multi-energy combined power supply are still met, the basic output power and battery compensation power are recalculated. When the conditions for multi-energy combined power supply are no longer met, the multi-energy combined power supply allocation process is exited, and the power supply mode is re-determined based on the current state.

[0086] Specifically, when entering the multi-energy joint power supply power allocation, the current total power demand is first obtained. The basic power supply branch can currently provide basic output power. Then, based on the current total power demand... The basic power supply branch can currently provide basic output power. The magnitude relationship between the values ​​determines whether the battery pack needs power compensation; when power compensation is performed, the output compensation power of the battery pack is as shown in formula (8):

[0087] When a multi-energy combined power supply mode is selected, the basic power supply branch provides the base power, and the battery storage unit provides the compensation power. The base power supply branch currently provides the base output power... Not less than the current total power requirement of the engineering vehicle At that time, the battery pack energy storage unit does not perform power compensation; when the basic power supply branch can currently provide basic output power... Below the current total power demand of engineering vehicles When the battery pack energy storage unit compensates for the difference, the compensation power shall not exceed the maximum allowable discharge power of the battery pack.

[0088] Through multi-energy coordinated control, the engineering vehicle can operate with high reliability in emergency repair and long-distance traction conditions, avoiding mission interruption due to single energy failure and improving the emergency support capability of rail transit.

[0089] Example 3: Selection of Normal Operating Mode When the engineering vehicle is not currently engaged in nighttime tunnel maintenance or emergency long-distance traction, the power management control unit determines the power supply mode based on the contact network status, battery pack charge status, environmental constraints, and high power demand status.

[0090] If the overhead contact line is available and power can be drawn from the pantograph, i.e., the overhead contact line status value... Furthermore, the engineering vehicle is not in a high-power demand state, that is... Then select the overhead contact line power supply mode. .

[0091] If the overhead contact line is unavailable or power cannot be drawn from the pantograph, i.e., the overhead contact line status value Furthermore, if the engineering vehicle is located in a low-noise or low-emission restricted area, then the environmental limit state value... Furthermore, the state of charge (SOC) of the battery pack is not lower than the preset low charge threshold, i.e., the battery's usable state value. Then select the independent battery power supply mode. .

[0092] If the engineering vehicle is not in a high power demand state, such as starting, climbing, heavy-load traction, sudden load change, or emergency traction state. Furthermore, the overhead contact line is unavailable or pantograph raising is not permitted, i.e., the overhead contact line status value is... Furthermore, both the internal combustion power unit and the power generation unit are available, meaning the internal combustion power generation is in a usable state. The internal combustion engine power generation mode shall be selected if at least one of the following conditions is met. : (1) The state of charge (SOC) of the battery pack is less than the low charge threshold, i.e., the battery is in a usable state. ; (2) The engineering vehicle was not in nighttime, in tunnels, or in low-noise or low-emission restricted areas, i.e., environmental limit status values. .

[0093] If the engineering vehicle experiences starting acceleration, climbing, sudden load changes, or heavy traction during normal operation, the high power demand state value will be... When the battery storage unit is available and at least one of the overhead contact line power supply branch or the internal combustion power generation power supply branch is available, the multi-energy combined power supply mode should be selected. If the battery pack energy storage unit is unavailable, or if both the overhead contact line power supply branch and the internal combustion power generation power supply branch are unavailable, select the reduced power operation mode (or safe shutdown mode). .

[0094] By setting contact network status values, battery availability status values, internal combustion generator availability status values, environmental restriction status values, and high power demand status values, a mode selection rule is formed, enabling engineering vehicles to automatically select the current power supply mode according to actual working conditions, ensuring the flexibility and adaptability of the engineering vehicle's power supply mode selection; when a single power supply unit malfunctions, the power management control unit can redetermine the power supply mode based on the remaining available energy, and enter a power reduction operation mode or a safe shutdown mode when the power supply is insufficient, improving the safety and reliability of engineering vehicle operation.

[0095] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A hybrid electric power system for rail transit engineering vehicles, characterized in that, include: Internal combustion power unit, power generation unit, battery energy storage unit, overhead contact line power supply unit, traction drive unit, work load unit, and power management control unit; The internal combustion power unit provides power output to the engineering vehicle. The power generation unit is connected to the internal combustion power unit and converts the internal combustion power into electrical energy, providing electrical energy to the traction drive unit under conditions of no overhead contact line or high load. The battery pack energy storage unit stores electrical energy and provides compensating electrical energy to the traction drive unit under conditions of traction start-up, sudden load changes, or low-noise operation. The overhead contact line power extraction unit obtains electrical energy from the overhead contact line when the engineering vehicle is in the pantograph-raised state and charges the battery pack in the battery pack energy storage unit or supplies power to the traction drive unit. The traction drive unit converts electrical energy into mechanical energy to drive the operation of the engineering vehicle. The work load unit consumes electrical energy and performs maintenance, lighting, and other work functions for the engineering vehicle. The power management control unit is communicatively connected to the internal combustion power unit, power generation unit, battery pack energy storage unit, overhead contact line power extraction unit, traction drive unit, and work load unit, and selects the power supply mode and controls the operation of the traction drive unit according to the operating conditions of the engineering vehicle.

2. The hybrid electric power system for rail transit engineering vehicles according to claim 1, characterized in that, The power supply modes include overhead contact line power supply mode, battery independent power supply mode, internal combustion engine power generation mode, multi-energy combined power supply mode, reduced power operation mode, or safe parking mode. In the overhead contact line power supply mode, when the overhead contact line is available and pantograph power is permitted, the overhead contact line power unit supplies power to the traction drive unit and the engineering load. In the battery independent power supply mode, the engineering vehicle is independently powered by the battery storage unit at night, in tunnels, or in low-noise or low-emission restricted areas. In the internal combustion engine power generation mode, the internal combustion engine power unit drives the power generation unit to output electrical energy to power the engineering vehicle's traction drive unit and the engineering load. Power supply; the multi-energy combined power supply mode provides basic power through an internal combustion power generation branch consisting of an internal combustion power unit and a power generation unit, or through a contact network power supply branch consisting of a contact network power take-off unit, with compensation power provided by a battery energy storage unit; the power reduction operation mode or safe stop mode refers to the power management control unit limiting the output power of the traction drive unit when the available power supply capacity is insufficient or the key power supply unit is abnormal, so that the engineering vehicle runs to a safe area at low speed and low power; when the remaining power supply capacity is insufficient to maintain low-speed operation, the traction drive unit is controlled to cut off the traction output, and the braking system is used to stop the engineering vehicle safely.

3. A hybrid electric power system for rail transit engineering vehicles according to claim 1, characterized in that, The battery pack energy storage unit is used for at least: pure electric operation in tunnels and low-noise work areas, providing instantaneous power output for the traction drive unit, and balancing power fluctuations between different energy sources.

4. A hybrid electric power system for rail transit engineering vehicles according to claim 1, characterized in that, During nighttime maintenance or tunnel operations, when the overhead contact line is unavailable or pantograph power extraction is not permitted, and the state of charge (SOC) of the battery pack is not lower than a preset low charge threshold, the power management control unit controls the engineering vehicle to operate in an independent battery power supply mode. During emergency repairs and long-distance traction operations, the power management control unit determines the basic power supply branch based on the availability of the overhead contact line power supply branch and the internal combustion engine power supply branch, and the battery pack energy storage unit provides compensation power.

5. A control method for a hybrid electric system used in urban rail transit engineering vehicles, characterized in that, Includes the following steps: S1. Collect the operating status information of the engineering vehicle; the operating status information includes the power supply status of the overhead contact line, the status of the pantograph, the charging status of the battery pack, the operating status of the internal combustion power unit, the operating status of the power generation unit, the operating speed of the engineering vehicle, the traction power requirement, the load power of the engineering operation, the gradient of the line, the type of the work area, and the noise restriction information. S2. Based on the traction power requirement and the power of the engineering operation load, calculate the current total power requirement of the engineering vehicle; S3. Determine the current status of the engineering vehicle based on its operating status information. The operating status includes the overhead contact line status value, the battery availability status value, the internal combustion generator availability status value, the environmental restriction status value, and the high power demand status value. S4. Determine the current power supply mode based on the current status of the engineering vehicle; the power supply mode includes overhead contact line power supply mode, battery independent power supply mode, internal combustion engine power generation power supply mode, multi-energy combined power supply mode, power reduction operation mode or safe shutdown mode.

6. The control method for a hybrid electric system for urban rail transit engineering vehicles according to claim 5, characterized in that, The contact wire status value is used to characterize whether the contact wire is available and whether it is permissible to raise the pantograph to draw power; the battery availability status value is used to characterize whether the battery pack charge is not lower than the preset low charge threshold; the internal combustion power generation availability status value is used to characterize whether both the internal combustion power unit and the power generation unit are in an available state. The environmental limitation status value is used to characterize whether the engineering vehicle is currently in a nighttime, tunnel, low-noise, or low-emission restricted area; the high power demand status value is used to characterize whether the engineering vehicle is currently in a starting, climbing, heavy-load traction, load change, or emergency traction state.

7. The control method for a hybrid electric system for urban rail transit engineering vehicles according to claim 6, characterized in that, The current energy supply mode is determined based on the current status of the engineering vehicle as follows: When the engineering vehicle is in the state of starting, climbing, heavy-load traction, sudden load change or emergency traction, the battery pack charge SOC is not lower than the preset low charge threshold, and at least one of the overhead contact line power supply branch or internal combustion power generation power supply branch is available, the power management control unit selects the multi-energy combined power supply mode. When the engineering vehicle is not in the state of starting, climbing, heavy-load traction, sudden load change, or emergency traction, and the overhead contact line is available and allows for pantograph power extraction, the power management control unit prioritizes the overhead contact line power supply mode and charges the battery pack in the battery pack energy storage unit when the battery pack's state of charge (SOC) is lower than the preset low charge threshold. When the overhead contact line is unavailable or pantograph raising is not permitted, and the engineering vehicle is in a nighttime, tunnel, low-noise or low-emission restricted area, and the battery pack SOC is not lower than the low charge threshold, the power management control unit selects the battery independent power supply mode. When the engineering vehicle is not in the starting, climbing, heavy-load towing, load change, or emergency towing state; and the overhead contact line is unavailable or pantograph raising is not allowed; and both the internal combustion power unit and the generator unit are available; and at least one of the following conditions is met, the power management control unit selects the internal combustion engine generator power supply mode: (1) The state of charge (SOC) of the battery pack is less than the low charge threshold; (2) The engineering vehicle was not in a nighttime, tunnel, or low-noise or low-emission restricted area; When the engineering vehicle is in the state of starting, climbing, heavy-load traction, sudden load change or emergency traction, and the battery pack charge SOC is lower than the preset low charge threshold, the power management control unit determines whether the output power of the overhead contact line power supply branch or the internal combustion generator power supply branch can meet the current total power demand. If it can meet the demand, the corresponding single power supply mode is selected; if it cannot meet the demand, the power reduction operation mode or safe stop mode is entered. When none of the above power supply conditions are met, the power management control unit selects either the reduced power operation mode or the safe shutdown mode.

8. The control method for a hybrid electric system for urban rail transit engineering vehicles according to claim 5, characterized in that, Also includes: S5: Execute the corresponding energy supply control according to the current energy supply mode.

9. A control method for a hybrid electric system for urban rail transit engineering vehicles according to claim 8, characterized in that, The corresponding energy supply control is executed according to the current energy supply mode as follows: When the contact network power supply mode is determined, the contact network power take-off unit supplies power to the traction drive unit and the engineering operation load, and charges the battery pack energy storage unit when the battery pack charge SOC is lower than the preset low charge threshold. When the battery independent power supply mode is determined, the battery pack energy storage unit supplies power to the traction drive unit and engineering work load, and controls the internal combustion power unit to stop running or remain in standby mode. When the internal combustion engine is selected as the power generation mode, the internal combustion power unit drives the power generation unit to output electrical energy to power the traction drive unit and the engineering work load, and charges the battery energy storage unit according to the state of charge of the battery pack. When the multi-energy combined power supply mode is determined, the internal combustion power generation power supply branch consisting of the internal combustion power unit and the power generation unit, or the contact network power supply branch consisting of the contact network power taking unit, provides the basic power, and the battery pack energy storage unit provides the compensation power. When the power reduction operation mode or safe parking mode is determined, the power management control unit limits the output power of the traction drive unit, so that the engineering vehicle runs to a safe area at low speed and low power. When the remaining power supply capacity is insufficient to maintain low speed operation, the traction drive unit is controlled to cut off the traction output and cooperate with the braking system to stop the engineering vehicle safely.

10. The method according to claim 5, characterized in that, When the multi-energy combined power supply mode is determined, the basic power is provided by the internal combustion power generation power supply branch consisting of the internal combustion power unit and the power generation unit, or by the contact network power supply branch consisting of the contact network power collection unit. The compensation power is determined according to the current total power demand of the engineering vehicle and the basic output power that the basic power supply branch can currently provide, and the compensation power is provided by the battery pack energy storage unit.

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