A permanent magnet traction system and communication method controlled by CAN bus

Abstract

The present invention discloses a track permanent magnet traction system and a communication method controlled by a CAN bus, and belongs to the technical field of current conversion controllers. The system includes a controller and a current conversion power module; the controller includes a power module, a vehicle control module, a communication module and a current conversion control module, the communication module and the current conversion control module are both connected to the vehicle control module via an Ethernet bus, the vehicle control module, the communication module and the current conversion control module are connected to each other via an internal CAN bus, and the current conversion power module is connected to the current conversion control module. The present invention provides a track permanent magnet traction system and a communication method controlled by a CAN bus, which can not only save energy consumption, but also ensure the real-time and reliability of communication data transmitted between various modules.

Description

Technical Field

[0001] The invention relates to a track permanent magnet traction system and a communication method controlled by a CAN bus, belonging to the technical field of current converter controllers. Background Art

[0002] At present, in rail transit vehicles, in order to respond to the energy-saving and green trend of rail transit, the rail traction system has also developed from the original vehicle-controlled traction using asynchronous motors to the more energy-efficient permanent magnet motor axle-controlled traction. Compared with the vehicle-controlled traction, which uses one inverter to drive four asynchronous traction motors, the axle-controlled traction is changed to four inverters driving four permanent magnet traction motors respectively. The corresponding original inverter controller controls one inverter power module, and the permanent magnet traction controller controls four inverter power modules. However, the problem with the above structure is that the energy consumption is too high, which cannot meet the requirements of green energy saving, and the real-time and reliability of the communication data transmitted between the modules cannot be guaranteed. Summary of the invention

[0003] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a track permanent magnet traction system and a communication method controlled by a CAN bus, which can not only save energy consumption but also ensure the real-time and reliability of communication data transmitted between modules.

[0004] In order to solve the above technical problems, the technical solution of the present invention is:

[0005] On one hand, the present invention provides a track permanent magnet traction system controlled by a CAN bus, which includes a controller and a current conversion power module;

[0006] The controller includes a power module, a vehicle control module, a communication module and a current conversion control module. The communication module and the current conversion control module are connected to the vehicle control module via an Ethernet bus. The vehicle control module, the communication module and the current conversion control module are connected to each other via an internal CAN bus. The current conversion power module is connected to the current conversion control module.

[0007] The power supply module is used to supply power to each module in the controller;

[0008] The vehicle control module is used to run the vehicle control main program to control the vehicle and the related electrical equipment of the traction system;

[0009] The inverter control module is used to run the inverter main program and control the inverter power module according to the instructions of the vehicle control module;

[0010] The communication module is used to provide communication connections between multiple traction systems.

[0011] Furthermore, one vehicle control module is provided, one communication module is provided, four current conversion control modules are provided, and four current conversion power modules are provided, and each current conversion control module controls one current conversion power module.

[0012] Furthermore, when used for axle-controlled traction, one vehicle control module is used to control four current conversion control modules, and then the four current conversion control modules respectively drive four permanent magnet motors through four current conversion power modules.

[0013] Furthermore, when used for frame-controlled traction, one vehicle control module is used to control two current conversion control modules, and then each current conversion control module drives two parallel asynchronous induction motors through two parallel current conversion power modules.

[0014] Furthermore, when used for vehicle control traction, one vehicle control module is used to control one current conversion control module, and then one current conversion control module drives four parallel asynchronous induction motors through one current conversion power module.

[0015] Furthermore, when used for auxiliary inverter, one vehicle control module is used to control one current conversion control module, and then one current conversion control module drives one current conversion power module to invert and output the vehicle auxiliary power supply.

[0016] Another aspect of the present invention provides an internal CAN network communication method of a track permanent magnet traction system controlled by a CAN bus, which comprises the following steps:

[0017] Real-time control of the internal CAN bus, using CAN standard frames to send and receive data;

[0018] The CAN data frame ID is used to identify the data transmission cycle, device number, and data definition;

[0019] According to the priority of the transmitted data, the data is allocated to four cycles for transmission, and the four cycles are cycle T1, cycle T2, cycle T3, and cycle T4;

[0020] Set up an independent heartbeat data frame for each cycle.

[0021] Furthermore, the priority of data transmitted in period T1 is higher than that of data transmitted in period T2, the priority of data transmitted in period T2 is higher than that of data transmitted in period T3, and the priority of data transmitted in period T3 is higher than that of data transmitted in period T4.

[0022] Furthermore, in period T1, the vehicle control module transmits instructions and data with the highest real-time requirements and security protection;

[0023] In period T2, the vehicle control module and the power conversion control module transmit power conversion control instructions and data with high real-time requirements;

[0024] In period T3, the vehicle control module and the power conversion control module transmit electrical control commands and data with lower real-time requirements;

[0025] In period T4, the vehicle control module and the power conversion control module transmit commands and data of the operating environment with the lowest real-time requirement.

[0026] By adopting the above technical scheme, the present invention divides the main functions into two parts: vehicle control and current conversion. The vehicle control module of the controller controls the operation of the current conversion control module through the CAN bus. The operation of one current conversion control module can be controlled by one vehicle control module for vehicle control traction; the operation of two current conversion control modules can be controlled by one vehicle control module for frame control traction; the operation of four current conversion control modules can be controlled by one vehicle control module for axle control traction. In addition to driving the traction motor, the current conversion control module can also be used for other current conversion applications in rail transit to perform auxiliary inverter, DC step-down, rectification and other current conversion functions, which is beneficial to saving energy. In addition, the controller provided by the present invention communicates between modules through the internal CAN bus, ensuring the real-time and reliability of the control network. The module with the main control is connected via Ethernet to provide debugging and non-real-time data data transmission between modules. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a principle block diagram of a track permanent magnet traction system controlled by a CAN bus of the present invention;

[0028] Figure 2 A schematic diagram of a board of the controller of the present invention;

[0029] Figure 3 It is a schematic diagram of the controller for integrating train control, assistance and traction of a vehicle according to the present invention. DETAILED DESCRIPTION

[0030] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments in conjunction with the accompanying drawings.

[0031] Embodiment 1

[0032] like Figure 1 As shown, this embodiment provides a rail permanent magnet traction system controlled by a CAN bus, which includes a controller and a converter power module.

[0033] like Figure 2As shown, the controller includes a power module, a vehicle control module, a communication module and a current conversion control module. The communication module and the current conversion control module are connected to the vehicle control module through an Ethernet bus. The vehicle control module, the communication module and the current conversion control module are connected to each other through an internal CAN bus. The current conversion power module is connected to the current conversion control module. In particular, there is one vehicle control module, one communication module, four current conversion control modules, and four current conversion power modules, and each current conversion control module controls one current conversion power module.

[0034] Hall sensors are installed on the inverter power module to measure input and output current, voltage, etc.

[0035] The power module is used to supply power to various modules in the controller and the Hall sensors on the inverter power module.

[0036] The vehicle control module is used to run the vehicle control main program to control the vehicle and related electrical equipment of the traction system.

[0037] The inverter control module is used to run the inverter main program. According to the instructions of the vehicle control module, it controls the inverter power module to realize functions such as traction, inversion, rectification, and charging.

[0038] The communication module is used to provide communication connections between multiple traction systems.

[0039] The vehicle control module connects multiple converter control modules through the CAN bus to achieve overall converter communication control, high-voltage power on and off, DC bus voltage control and monitoring protection, temperature monitoring and cooling control, traction command control, etc. It manages the internal CAN network, traction local MVB / CAN network, vehicle MVB / TRDP network, controls and monitors parts related to the converter as a whole, and forwards vehicle network and converter command signals.

[0040] The inverter control module software uses a time-triggered task scheduling method based on the underlying embedded real-time operating system to implement input and output control, state timing, fault diagnosis, protection monitoring, communication management, system logic and other functions. After the underlying hardware initialization and self-test are completed, the application layer initialization task is executed. After the initialization is completed, the tasks required to be executed are executed in different thread cycles, and the inverter control is executed according to the CAN communication instructions sent by the vehicle control module.

[0041] This embodiment decomposes the original 1MW converter of the vehicle into four independently controllable 250KW converters. The four independent converters can perform different conversion tasks to meet the different conversion function requirements of the vehicle circuit:

[0042] 1. Used as a traction inverter

[0043] When used for axle-controlled traction, one vehicle control module is used to control four power conversion control modules, and then the four power conversion control modules drive four permanent magnet motors through four power conversion modules respectively.

[0044] When used for frame-controlled traction, one vehicle control module controls two current conversion control modules, and then each current conversion control module drives two parallel asynchronous induction motors through two parallel current conversion power modules. During frame-controlled traction, two parallel asynchronous induction motors are installed on each of the two bogies, and the two parallel asynchronous induction motors on each bogie are controlled by one current conversion control module.

[0045] When used for vehicle control traction, one vehicle control module is used to control one current conversion control module, and then one current conversion control module drives four parallel asynchronous induction motors through one current conversion power module.

[0046] 2. Used as an auxiliary inverter

[0047] When used for auxiliary inverter, the converter control module can drive the inverter to output AC380V vehicle auxiliary power, and drive the inverter to perform rectification, voltage reduction and other operations to provide various power supplies for on-board equipment.

[0048] The controller of this embodiment can also meet the needs of various applications by replacing functional modules.

[0049] For example: when used as an auxiliary inverter of a rail transit vehicle, one converter control module is used to complete auxiliary inversion, and another converter control module can be used to complete the control of the step-down converter to charge the on-board emergency traction battery.

[0050] like Figure 3 As shown, three controllers are used to integrate the vehicle's train control, auxiliary, and traction controllers, reducing the number of devices and lowering costs.

[0051] Embodiment 2

[0052] This embodiment provides an internal CAN network communication method of a track permanent magnet traction system controlled by a CAN bus as in Embodiment 1, which comprises the following steps:

[0053] Real-time control of the internal CAN bus, using a 1Mbps communication speed. Using CAN standard frames to send and receive data, each frame can transmit 1 to 8 bytes of data.

[0054] The CAN data frame ID is used to identify the data transmission cycle, device number, and data definition; as shown in Table 1:

[0055] Table 1

[0056]

[0057] Among them, ID0-2 is 4 cycles T1, cycle T2, cycle T3 and cycle T4;

[0058] ID3-5 is the device number, the vehicle control module is defined as 0, and the four inverter control modules are defined as 1, 2, 3, and 4 respectively.

[0059] ID6-10 has a total of 64 frames of data, and each data is defined separately in the software.

[0060] According to the priority of the transmitted data, the data is allocated to four cycles for transmission, and the four cycles are cycle T1 (4mS), cycle T2 (16mS), cycle T3 (64mS), and cycle T4 (512mS).

[0061] An independent heartbeat data frame is set for each cycle to ensure the real-time and reliability of the communication data. For example, the traction and braking signals with higher real-time requirements are transmitted in the T2 cycle, and the temperature signals with lower real-time requirements are transmitted in the T4 cycle.

[0062] In particular, the priority of data transmitted in period T1 is higher than that of data transmitted in period T2, the priority of data transmitted in period T2 is higher than that of data transmitted in period T3, and the priority of data transmitted in period T3 is higher than that of data transmitted in period T4.

[0063] As shown in Table 2, data is allocated to four cycles for transmission.

[0064] Table 2

[0065]

[0066] In cycle T1, the vehicle control module transmits instructions and data with the highest real-time requirements and security protection;

[0067] In period T2, the vehicle control module and the power conversion control module transmit power conversion control instructions and data with high real-time requirements;

[0068] In period T3, the vehicle control module and the inverter control module transmit electrical control commands and data with lower real-time requirements;

[0069] In period T4, the vehicle control module and the inverter control module transmit commands and data of the operating environment with the lowest real-time requirement.

[0070] 1. Data transmission of vehicle control module

[0071] In cycle T1, the vehicle control module sends the start command of the converter control module, the OVP test command, the blocking request command, the soft shutdown request command, the isolation request command, and other commands, and sends the DC pre-charge contactor closing feedback status information, the DC separation contactor closing feedback status information, the DC circuit breaker closing feedback status information, the DC bus voltage detection status information, etc.;

[0072] The vehicle control module sends traction commands, braking commands, forward commands, and backward commands within cycle T2, and sends train line forward status information, train line backward status information, train line zero speed status information, vehicle speed and other status information;

[0073] The vehicle control module sends the blocking brake command, stop command, removal command, converter test command and other commands within the cycle T3, and sends the three-phase voltage bus activation status information, high voltage enable status information, time status information, train weight correction coefficient status information, wheel diameter and other status information;

[0074] The vehicle control module sends line reactor temperature information, three-phase transformer temperature information, radiator temperature information, board temperature information, motor temperature and other information within cycle T4.

[0075] 2. Data transmission of the inverter control module

[0076] The converter control module sends commands such as closing the traction load circuit breaker, prohibiting the DC bus pre-charging, and prohibiting the line circuit breaker within the period T2; sends DC bus voltage status information, DC bus current status information, MCM status information, actual traction braking force status information, shaft speed status information, wheel speed status information, traction safety status information, idling and sliding status information, soft shutdown status information, protective shutdown status information, etc.

[0077] The current conversion control module sends motor phase current status information, available dynamic braking force status information based on speed, forward state information, backward driving state information, driving mode and other status information within period T3;

[0078] The inverter control module will send software version information, brake resistor energy information, consumed energy information, regenerated energy information, running distance information, internal air temperature information, brake resistor temperature information, fault event group and other information within cycle T4.

[0079] In summary, the vehicle control module and the power conversion control module send instructions and data of different priorities through different communication cycles to meet the real-time requirements of vehicle control. The vehicle control module will send power conversion control instructions in time according to the status of the vehicle and the power conversion control module. The power conversion control module also assists the vehicle control module in making decisions by feeding back status information.

[0080] The vehicle control module and the converter control module are powered on, self-checked, and communicated. The vehicle control module, as the master device, identifies the converter control module and the communication module on the internal CAN bus and controls each module through the application program.

[0081] The vehicle control module reads the data of each module through the real-time network CAN bus and sends instructions and data to each module.

[0082] The specific embodiments described above further illustrate the technical problems, technical solutions and beneficial effects solved by the present invention. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A permanent magnet track traction system controlled by a CAN bus, characterized in that: It includes a controller and a converter power module; The controller includes a power module, a vehicle control module, a communication module and a current conversion control module. The communication module and the current conversion control module are connected to the vehicle control module via an Ethernet bus. The vehicle control module, the communication module and the current conversion control module are connected to each other via an internal CAN bus. The current conversion power module is connected to the current conversion control module. The power supply module is used to supply power to each module in the controller; The vehicle control module is used to run the vehicle control main program to control the vehicle and the related electrical equipment of the traction system; The inverter control module is used to run the inverter main program and control the inverter power module according to the instructions of the vehicle control module; The communication module is used to provide communication connection between multiple traction systems; The vehicle control module is provided with one, the communication module is provided with one, the current conversion control modules are provided with four, the current conversion power modules are provided with four, and each of the current conversion control modules controls one current conversion power module; When used for axle-controlled traction, one vehicle control module controls four current conversion control modules, which then drive four permanent magnet motors through four current conversion power modules. When used for frame control traction, one vehicle control module controls two current conversion control modules, and then each current conversion control module drives two parallel asynchronous induction motors through two parallel current conversion power modules; When used for vehicle control traction, one vehicle control module is used to control one current conversion control module, and then one current conversion control module drives four parallel asynchronous induction motors through one current conversion power module.

2. The track permanent magnet traction system controlled by CAN bus according to claim 1, characterized in that: When used for auxiliary inverter, one vehicle control module is used to control one current conversion control module, and then one current conversion control module drives one current conversion power module to invert and output the vehicle auxiliary power supply.

3. An internal CAN network communication method of a track permanent magnet traction system controlled by a CAN bus as claimed in any one of claims 1 to 2, characterized in that: It includes the following steps: Real-time control of the internal CAN bus, using CAN standard frames to send and receive data; The CAN data frame ID is used to identify the data transmission cycle, device number, and data definition; According to the priority of the transmitted data, the data is allocated to four cycles for transmission; Set up an independent heartbeat data frame for each cycle.

4. The internal CAN network communication method according to claim 3, characterized in that: The four periods are period T1, period T2, period T3 and period T4 respectively.

5. The internal CAN network communication method according to claim 3, characterized in that: The priority of data transmitted in period T1 is higher than that of data transmitted in period T2, the priority of data transmitted in period T2 is higher than that of data transmitted in period T3, and the priority of data transmitted in period T3 is higher than that of data transmitted in period T4.

6. The internal CAN network communication method according to claim 3, characterized in that: In period T1, the vehicle control module transmits safety protection instructions and data; In period T2, the vehicle control module and the power conversion control module transmit power conversion control instructions and data; In period T3, the vehicle control module and the inverter control module transmit electrical control commands and data; In period T4, the vehicle control module and the power conversion control module transmit commands and data of the operating environment.

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