Electronic assembly for energy supply of a railway vehicle

Abstract

Electronic components (12), including power supplies (14, 24) and power receiving units (18, 20, 22), are connected via a DC link (26). A line converter module (28) is arranged between the current collector (14) and the DC link (26). A line converter control device (LCCD) controls the line converter module (28). The power supply includes a rechargeable battery (24) and a battery management system (BMS), which is directly connected to the DC link (26). The power receiving unit includes at least one motor (18) with a motor converter module (30) arranged between the DC link (26) and the motor (18). A motor converter control device (MCCD) controls the motor converter module (30). The battery (24) is controlled and monitored by the line converter control device (LCCD) and / or by the motor converter control device (MCCD).

Description

Technical Field

[0001] This invention relates to an electronic component for supplying energy to railway vehicles. Background Technology

[0002] In the prior art, a railway vehicle is known that includes a power supply and a power receiving unit connected together via a DC link, wherein: - The power supply includes a current collector designed to collect AC power from an external AC power source, and a line converter arranged between the current collector and the DC link. The vehicle includes a line converter control device (LCCD) that controls the line converter. - The power source includes a rechargeable battery that is connected to a DC link. - The power receiving unit includes at least one motor and a motor converter, and the vehicle includes a motor converter control device (MCCD) that controls the motor converter.

[0003] Typically, a rechargeable battery is connected to a DC link via a DC / DC chopper, which is designed to convert DC input into a variable DC output. This chopper allows control of DC voltage from current collectors and / or from the motor to the battery, and control of DC voltage from the battery to the motor. Summary of the Invention

[0004] The present invention aims to modify the electronic component to save costs, weight and space, and reduce energy consumption.

[0005] Therefore, the present invention relates to an electronic component for railway vehicles, comprising a power supply and a power receiving unit connected via a DC link, wherein: - The power supply includes a current collector designed to collect AC power from an external AC power source, and a line converter module disposed between the current collector and the DC link. This electronic component includes a line converter control device (LCCD) that controls the line converter module. - The power source includes a rechargeable battery and a battery management system (BMS), which is directly connected to the DC link. - The power receiving unit includes at least one motor and has a motor converter module disposed between the DC link and the motor. This component includes a motor converter control device (MCCD) that controls the motor converter module. The battery is characterized in that it is controlled and monitored by a line converter control device (LCCD) and / or a motor converter control device (MCCD).

[0006] This invention allows batteries to be directly connected to a DC link without a DC / DC chopper. Removing the chopper allows for savings in cost, weight, and space.

[0007] This is achieved by handling the charging and discharging of the battery through the line converter control device (LCCD) and the motor converter control device (MCCD).

[0008] It should be noted that LCCD and MCCD are devices already implemented in the prior art. In this invention, their software is modified to control the battery. Therefore, no additional control computer is required in this invention, thus eliminating additional cost, weight, or size.

[0009] The electronic components according to the present invention may include any one of the following features, individually or in any possible combination: - The electronic component includes at least one internal communication network through which communication between the battery management system (BMS), the line converter control device (LCCD), and the motor converter control device (MCCD) takes place.

[0010] - The line converter control device (LCCD) is configured to control the input power to the DC link to balance the power consumption of the motor converter module and the battery, and to keep the DC link voltage at the level that generates the desired battery current.

[0011] - The motor converter control device (MCCD) is configured to adjust its power when the operation of the line converter control device (LCCD) is limited, in order to balance battery power and keep the DC link voltage at a level that produces the desired battery current.

[0012] The battery management system (BMS) provides parameters to the line converter control device (LCCD) and the motor converter control device (MCCD), including reference battery voltage and current, as well as the measured battery current.

[0013] - The line converter control device (LCCD) is configured to meet the desired battery current under unrestricted contact line operation, and the motor converter control device (MCCD) is configured to control the battery current under restricted contact line operation.

[0014] - The line converter control device (LCCD) is configured to communicate the status of the line converter module to the motor converter control device (MCCD).

[0015] The present invention also relates to a railway vehicle, characterized in that it includes electronic components as previously disclosed. Attached Figure Description

[0016] Several aspects and advantages of the present invention will be set forth in the following disclosure, which are given by way of non-limiting example only, and with reference to the accompanying drawings, wherein: - Figure 1This is a schematic diagram of an example of a railway vehicle motor electronic assembly according to an embodiment of the present invention. Detailed Implementation

[0017] Figure 1 A railway vehicle 10 with electronic components 12 is shown schematically.

[0018] Electronic component 12 includes a power source comprising a current collector 14 designed to collect alternating current (AC) from an external AC power source 16. For example, current collector 14 is a pantograph, and AC power source 16 is an overhead line. In one variation, AC power source 16 is a power rail or any other possible power source.

[0019] The power source also includes a rechargeable battery 24. A battery management system (BMS) is designed to manage battery 24.

[0020] Specifically, the battery management system (BMS) can specify a battery current reference, particularly based on the battery's state of charge, in a known manner. Typically, energy can be stored in the battery (negative battery current) or extracted from the battery (positive current), independent of operation. Battery charging / discharging is controlled by the reference current defined by the BMS.

[0021] Electronic component 12 also includes a power receiving unit, including a motor 18, a braking resistor 20, and an auxiliary inverter 22.

[0022] Electronic component 12 includes a connection component, commonly referred to as a “DC link” 26, which forms a connection between current collector 14, battery 24 and power receiving units 18, 20, 22.

[0023] According to the present invention, the rechargeable battery 24 is directly connected to the DC link 26. By "directly connected," we mean that only a cable connects the battery 24 to the DC link 26. More specifically, there is no DC / DC chopper between the battery 24 and the DC link 26 in the electronic component 12. Since the battery 24 is directly connected to the DC link 26, the battery current is directly generated by the actual DC link voltage. Therefore, it is necessary to control the DC link voltage to always generate the desired current for the battery 24.

[0024] The DC link voltage is controlled to substantially always meet the reference battery voltage and current from the battery management system (BMS). The control of the DC link voltage will be disclosed later.

[0025] A line converter module (LCM) 28 is disposed between the current collector 14 and the DC link 24. The line converter module 28 is designed to convert alternating current (AC) from the current collector 14 into direct current (DC) to power the receiving unit and / or battery 24 via the DC link 26.

[0026] Vehicle 10 includes a line converter control device (LCCD) that controls the line converter module 28.

[0027] Electronic component 12 also includes a motor converter module (MCM) 30 disposed between DC link 24 and motor 18, and a motor converter control device (MCCD) for controlling the motor converter module 30. Preferably, the motor converter control device (MCCD) also controls the power of the braking chopper.

[0028] According to the present invention, the battery management system (BMS) communicates with the line converter control device (LCCD) and the motor converter control device (MCCD) to enable the LCCD and MCCD to control and supervise the battery 24. Preferably, communication between the battery management system (BMS), the LCCD, and the MCCD is conducted via an internal communication network 32. This internal communication network 32 is preferably a pre-existing network already implemented in prior art vehicles.

[0029] In one example, the LCCD software communicates with the MCCD software via the ICE bus.

[0030] The DC link voltage is the result of the net input power to the DC link. During normal operation (i.e., when the LCM can operate freely), the LCCD controls the input power from the power line to the DC link 26 to balance the power consumption of the motor converter and the battery (both motor power and battery power can be positive or negative), and always maintains the DC link voltage at the desired level under all operating conditions to generate the desired battery current, thereby meeting the battery's charging / discharging requirements (defined by the battery management system).

[0031] Therefore, the LCCD software preferably requires parameters from the battery management system to control the charging / discharging of the battery. These parameters are, for example, a reference battery voltage and current, and a measured battery current (preferably measured by a physical current sensor). The reference battery voltage and current are provided by the battery management system, for example, via a CAN or IP network. This parameter can be variable.

[0032] It should be noted that the LCM status defines which device (LCCD or MCCD) is responsible for controlling the DC link voltage. The LCM (Line Converter Module) status indicates whether the converter is blocked and whether the LCM is under active power limitation during commutation.

[0033] In unrestricted overhead contact line operation, the LCCD charges the battery in all operating modes, while the MCCD charges the battery in restricted modes, where the LCM may be blocked or under active power limitation. Alternatively, the battery can also discharge if the battery current reference is negative.

[0034] Therefore, if the LCM stops operating (e.g., due to pantograph bounce, entering the neutral zone, or a fault), or if the LCM's operation is restricted to meet the permissible line current requirements (line power limitation), the LCCD will no longer be able to maintain the DC link voltage at the desired level (for battery charging / discharging).

[0035] In this situation, in order to continue controlling the DC link to meet the battery charging / discharging requirements, the motor power and / or overvoltage / braking chopper power must be adjusted to control the DC link voltage.

[0036] Therefore, when the line converter control device (LCCD) stops, the motor converter control device (MCCD) adjusts the power of the motor converter and / or brake chopper to balance the battery power and keep the DC link 26 voltage at the level that produces the desired battery current.

[0037] Therefore, the status of the line converter current limit (and whether the line converter is not in operation) is transmitted from the LCCD to the MCCD, for example via the ICE bus.

[0038] The MCCD already has the function of limiting the DC link current as a function of the DC link voltage. In the new "battery charging mode," the DC link current limiting function is used to adjust the motor converter power (including chopper power) to maintain the battery current at its reference value instead of satisfying the DC link current limit. In principle, in this mode, the DC link current limit is simply replaced by the reference battery current. The MCCD software also preferably requires parameters from the battery management system and / or from the LCCD to control the battery charging / discharging. These parameters are, for example, the reference battery voltage and current, the measured battery current, and the state of LCCD control, i.e., whether the LCM is blocked or under current limiting.

[0039] The actual DC link voltage level is a result of the net input power to the DC link (dynamic system), where the LCM (with LCCD control) controls the power flow into and out of the power line, and the MCM (with MCCD control) controls the motor power, which can be positive or negative. Additionally, the propulsion system includes a so-called overvoltage / braking chopper, an additional system component attached to the DC link that dissipates power into a dedicated resistor. This component is also controlled by the MCCD, and the power through this system can be used to temporarily limit the DC link voltage to dangerous levels, or to dissipate additional power from the DC link if the desired braking power fed into the DC link exceeds the power leaving the DC link (returning to the power line and / or into the battery).

[0040] However, modifying the motor power means modifying the braking torque compared to the torque reference, which is clearly undesirable (this would require additional mechanical braking to meet the total braking demand). The desired braking command can be achieved by the possibility of dissipating power via an overvoltage / braking resistor, i.e., also when LCM operation is limited, where excess input power (i.e., the difference between the motor power fed into the DC link and the power leaving the DC link to the line and / or to the battery) is dissipated in the resistor.

[0041] This is then achieved at the cost of maintaining braking torque, and at the cost of additional power losses on the resistors (which reduces the system's energy efficiency).

[0042] To allow for maximum flexibility, all possibilities should be considered, and the total power flow into and out of the DC link should be controlled by using all available components attached to the DC link, always keeping the DC link at a level that meets the battery's desired charge / discharge requirements. If an overvoltage / braking chopper is available and the LCM is limited, one can choose to maintain the desired braking torque and dissipate excess input power in the overvoltage / braking chopper, or not operate the overvoltage / braking chopper and instead reduce the braking torque.

[0043] In all cases, the DC link voltage is controlled to generate the desired battery current. It should be noted that this invention can be applied to any railway application with AC power.

Claims

1. An electronic assembly (12) for a railway vehicle (10), comprising a power supply (14, 24) and a power receiving unit (18, 20, 22), connected via a DC link (26), wherein: - The power supply includes a current collector (14) designed to collect AC power from an external AC power source (16) and a line converter module (28) disposed between the current collector (14) and the DC link (26). The electronic component (12) includes a line converter control device (LCCD) that controls the line converter module (28). - The power source includes a rechargeable battery (24) and a battery management system (BMS), which is directly connected to a DC link (26). - The power receiving unit includes at least one motor (18) and has a motor converter module (30) between the DC link (26) and the motor (18). The component (12) includes a motor converter control device (MCCD) that controls the motor converter module (30). The battery (24) is characterized in that it is controlled and monitored by a line converter control device (LCCD) and / or a motor converter control device (MCCD).

2. The electronic component (12) according to claim 1, comprising at least one internal communication network (32) through which communication between the battery management system (BMS), the line converter control device (LCCD) and the motor converter control device (MCCD) is performed.

3. The electronic component (12) according to claim 1 or 2, characterized in that, The line converter control device (LCCD) is configured to control the input power to the DC link (26) to balance the power consumption of the motor converter module (30) and the battery (24) and to keep the DC link voltage at a level that generates the desired battery current.

4. The electronic component (12) according to any one of the preceding claims, characterized in that, The motor converter control device (MCCD) is configured to adjust its power when the operation of the line converter control device (LCCD) is limited, in order to balance battery power and keep the DC link voltage at a level that produces the desired battery current.

5. The electronic component (12) according to any one of the preceding claims, characterized in that, The battery management system (BMS) provides parameters to the line converter control device (LCCD) and the motor converter control device (MCCD), including reference battery voltage and current, as well as the measured battery current.

6. The electronic component (12) according to any one of the preceding claims, characterized in that, The line converter control device (LCCD) is configured to meet the desired battery current under unrestricted contact line operation, and the motor converter control device (MCCD) is configured to control the battery current under restricted contact line operation.

7. The electronic component (12) according to any one of the preceding claims, characterized in that, The line converter control device (LCCD) is configured to communicate the status of the line converter module (28) to the motor converter control device (MCCD).

8. A railway vehicle (10), characterized in that, It includes the electronic component (12) according to any one of the preceding claims.

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