CN106877681B - It is a kind of for the supply convertor of Electronically Controlled Pneumatic Brake Systems and balance of flux adjusting method - Google Patents

Abstract

The invention discloses a power converter and a magnetic flux balance adjustment method for an electronically controlled air brake system. The power converter includes a first main power board, a second main power board, a driving circuit, a control circuit and a switching circuit ; The input and output ends of the first main power board and the second main power board are respectively connected to the locomotive 110V power supply and the switching circuit through the locomotive power supply bus and PCB wiring; wherein, the main topology of the first main power board uses The push-pull forward topology solves the magnetic flux balance problem in the traditional push-pull circuit by adding a magnetic flux balance regulator; the power converter is suitable for various environments and provides power for the ECP braking system. The invention solves the problems of unbalanced magnetic flux of the push-pull circuit and normal operation in complex environments, etc., and has good application prospects.

Description

A power converter and magnetic flux balance adjustment for an electronically controlled air brake system method

technical field

The invention belongs to the field of railway locomotive braking, and relates to a power converter for an electronically controlled air braking system and a magnetic flux balance adjustment method.

Background technique

As the daily number of railway locomotives gradually increases, ensuring the safe operation of locomotives is one of the most important tasks. Although the traditional power converter can realize the basic power conversion function, its design process does not take into account the high temperature environment in the working process of the actual locomotive power converter. Still able to work normally. At the same time, it cannot meet the small volume requirement of the power converter during the operation of the locomotive. The traditional power converter also has some protection measures, but the design process does not take into account the protection requirements of the locomotive power converter, and cannot guarantee that the power converter can protect the power converter in time under various emergencies (such as short circuit and overload). Compared with the external circuit, no corresponding measures have been taken for various special protection requirements and indicators (such as quick response indicators) of the locomotive power converter. This has left a hidden danger to the locomotive safety. During the working process of the traditional push-pull topology converter, the problem of unbalanced magnetic flux cannot be avoided. Since the electric control air brake system of the locomotive needs to ensure the stable and reliable operation of each part of the power converter in real time when the locomotive is running, the problem of unbalanced magnetic flux also leaves hidden dangers to driving safety. In order to strengthen the power supply quality control of the electronically controlled air brake system of locomotives and improve the safety and stability of the system, it is necessary to develop a power converter for the electronically controlled air brake system to provide a good platform for the power supply of the system.

Contents of the invention

In order to solve the technical problem of power supply for the electronically controlled air brake system of a locomotive, the invention provides a power converter and a magnetic flux balance adjustment method for the electronically controlled air brake system.

A power converter for an electronically controlled air brake system, comprising a first main power board, a second main power board, a drive circuit, a control circuit and a switching circuit;

The input end and the output end of the first main power board and the second main power board are respectively connected to the locomotive 110V power supply and the switching circuit through the locomotive power supply bus and PCB wiring;

The locomotive 110V power supply, the first main power board and the drive circuit are connected to the control circuit through PCB wiring, control circuit bus and PWM output bus respectively;

The output end of the drive circuit is connected to the first main power board;

The switching circuit is connected to an external power load through a power output bus;

The first main power board includes a first input filter module, a transformer push-pull forward topology module, a full-bridge rectifier circuit, a peak absorption network module, and a first output filter module connected in sequence;

The PWM modulation circuit in the control circuit is connected with the transformer push-pull forward topology module through the drive circuit;

The second main power board includes a second input filter module, a flyback topology module, a second output filter module and an output protection module connected in sequence, and an input terminal of the flyback topology module and an output terminal of the output protection module are arranged There are control modules.

Further, the control circuit includes a control power supply, a current sampling module, a PWM modulation circuit, a magnetic flux balance regulator, an output protection module, a voltage sampling module, and a main circuit error regulator; the control power supply is connected to the locomotive power supply, and supply power to the control circuit;

The current sampling module collects two winding currents on the transformer push-pull forward topology module;

The voltage sampling module collects the voltage on the output terminal of the first main power board;

The current sampling module, the magnetic flux balance regulator and the PWM modulation circuit are connected in sequence;

The voltage sampling module, the main circuit error regulator and the PWM modulation circuit are connected in sequence;

The output end of the first main power board is connected to the PWM modulation circuit through the output protection module;

The control circuit is connected with the switching circuit.

Further, the magnetic flux balance regulator includes a differential module, a Type II error adjustment module, an inverting module, and a resistor divider network module;

The differential module is connected to the current sampling module in the control circuit;

The differential module, the type-two error adjustment module, the inverting module and the resistor divider network module are connected in sequence;

The output end of the inverter and the output end of the main circuit error regulator are all connected to the input end of the resistance voltage divider network module;

The output terminal of the resistor divider network is connected with the PWM modulation circuit.

Further, the drive circuit includes an optocoupler isolation module and a push-pull output module, the optocoupler isolation module is connected to the control circuit, and the push-pull output is connected to the first main power board.

A balance adjustment method for a power converter of an electronically controlled air brake system. First, two main power boards are used to connect to a locomotive 110V power supply and a switching circuit through a locomotive power supply bus and PCB wiring;

Secondly, the locomotive 110V power supply, the first main power board and the driving circuit are respectively connected to the control circuit through the PCB wiring, the control circuit bus and the PWM output bus, and the output end of the driving circuit is connected to the first main power board;

The switching circuit is connected to an external power load through a power output bus;

Set a flux balance regulator in the control circuit, use the flux balance regulator to perform differential processing on the two winding currents on the transformer in the first main power board, and input the signal data after differential processing to the second type error regulator The device obtains the current error adjustment value;

Next, an inverter is used to invert the voltage of the error regulator;

Finally, the inverting signal and current error adjustment value are interconnected with the output signal of the main circuit voltage error regulator by using a resistor divider network, thereby reducing or increasing the pulse width and realizing the balance adjustment of the power converter.

When the magnetic flux is biased towards the upper tube, the current of the upper tube will increase. After the sampling is performed by differential comparison, the signal is given to the voltage divider resistor to increase the voltage of the error regulator of the main circuit of the lower tube, and at the same time reduce the voltage of the error regulator of the main circuit of the upper tube. Reduce the pulse width of the upper tube and increase the pulse width of the lower tube; the same principle, when the magnetic flux is biased towards the lower tube, the current of the lower tube increases, and the signal is given to the voltage divider resistor to increase the voltage of the error regulator of the main circuit of the upper tube, and at the same time reduce The error regulator voltage of the main circuit of the lower tube increases the pulse width of the upper tube and reduces the pulse width of the lower tube.

Further, the first main power board includes a first input filter module, a transformer push-pull forward topology module, a full-bridge rectifier circuit, a peak absorption network module, and a first output filter module connected in sequence;

The PWM modulation circuit in the control circuit is connected with the transformer push-pull forward topology module through the drive circuit;

The second main power board includes a second input filter module, a flyback topology module, a second output filter module and an output protection module connected in sequence, and an input terminal of the flyback topology module and an output terminal of the output protection module are arranged There are control modules.

Beneficial effect

The invention provides a power converter and a magnetic flux balance adjustment method for an electronically controlled air brake system, the power converter includes a first main power board, a second main power board, a driving circuit, a control circuit and a switching circuit ; The input and output ends of the first main power board and the second main power board are respectively connected to the locomotive 110V power supply and the switching circuit through the locomotive power supply bus and PCB wiring; wherein, the main topology of the first main power board uses The push-pull forward topology solves the magnetic flux balance problem in the traditional push-pull circuit by adding a magnetic flux balance regulator; the power converter is suitable for various environments and provides power for the ECP braking system. The invention solves the problems of unbalanced magnetic flux of the push-pull circuit and normal operation in complex environments, etc., and has good application prospects.

Description of drawings

Fig. 1 is a schematic structural diagram of a power converter according to the present invention;

Figure 2 is a working schematic diagram of the flux balance regulator;

3 is a schematic diagram of the output performance test of the power converter of the present invention;

Fig. 4 is a schematic diagram of the application of the present invention to perform a parallel test of dual power supplies.

Detailed ways

The present invention will be further described below in conjunction with accompanying drawings and examples.

As shown in Figure 1, a power converter for an electronically controlled air brake system includes a first main power board, a second main power board, a drive circuit, a control circuit and a switching circuit;

The input end and the output end of the first main power board and the second main power board are respectively connected to the locomotive 110V power supply and the switching circuit through the locomotive power supply bus and PCB wiring;

The locomotive 110V power supply, the first main power board and the drive circuit are connected to the control circuit through PCB wiring, control circuit bus and PWM output bus respectively;

The output end of the drive circuit is connected to the first main power board;

The switching circuit is connected to an external power load through a power output bus;

The first main power board includes a first input EMI filter module, a transformer push-pull forward topology module, a full-bridge rectifier circuit, a peak absorption network module, and a first output EMI filter module connected in sequence;

The PWM modulation circuit in the control circuit is connected with the transformer push-pull forward topology module through the drive circuit;

The second main power board includes a second input EMI filter module, a flyback topology module, a second output EMI filter module and an output protection module connected in sequence, and the input terminal of the flyback topology module and the output terminal of the output protection module There is a control module between them.

The control circuit includes a control power supply, a current sampling module, a PWM modulation circuit, a magnetic flux balance regulator, an output protection module, a voltage sampling module and a main circuit error regulator; the control power supply is connected with the locomotive power supply, and is a control circuit powered by;

The current sampling module collects two winding currents on the transformer push-pull forward topology module;

The voltage sampling module collects the voltage on the output terminal of the first main power board;

The current sampling module, the magnetic flux balance regulator and the PWM modulation circuit are connected in sequence;

The voltage sampling module, the main circuit error regulator and the PWM modulation circuit are connected in sequence;

The output end of the first main power board is connected to the PWM modulation circuit through the output protection module;

The control circuit is connected with the switching circuit.

The magnetic flux balance regulator includes a differential module, a type-two error adjustment module, an inverting module, and a resistor divider network module;

The differential module is connected to the current sampling module in the control circuit;

The differential module, the type-two error adjustment module, the inverting module and the resistor divider network module are connected in sequence;

The output end of the inverter and the output end of the main circuit error regulator are all connected to the input end of the resistance voltage divider network module;

The output terminal of the resistor divider network is connected with the PWM modulation circuit.

The drive circuit includes an optocoupler isolation module and a push-pull output module, the optocoupler isolation module is connected to the control circuit, and the push-pull output is connected to the first main power board.

A magnetic flux balance adjustment method for a power converter of an electronically controlled air brake system. First, two main power boards are used to connect to a locomotive 110V power supply and a switching circuit through a locomotive power supply bus and PCB wiring;

Secondly, the locomotive 110V power supply, the first main power board and the driving circuit are respectively connected to the control circuit through the PCB wiring, the control circuit bus and the PWM output bus, and the output end of the driving circuit is connected to the first main power board;

The switching circuit is connected to an external power load through a power output bus;

A magnetic flux balance regulator is set in the control circuit, as shown in Figure 2, the flux balance regulator is used to perform differential processing on the two winding currents on the transformer in the first main power board, and the differentially processed signal data input to the type II error regulator to obtain the current error adjustment value;

Next, an inverter is used to invert the voltage of the error regulator;

Finally, the inverting signal and current error adjustment value are interconnected with the output signal of the main circuit voltage error regulator by using a resistor divider network, thereby reducing or increasing the pulse width and realizing the balance adjustment of the power converter.

When the magnetic flux is biased towards the upper tube, the current of the upper tube will increase. After the sampling is performed by differential comparison, the signal is given to the voltage divider resistor to increase the voltage of the error regulator of the main circuit of the lower tube, and at the same time reduce the voltage of the error regulator of the main circuit of the upper tube. Reduce the pulse width of the upper tube and increase the pulse width of the lower tube; the same principle, when the magnetic flux is biased towards the lower tube, the current of the lower tube increases, and the signal is given to the voltage divider resistor to increase the voltage of the error regulator of the main circuit of the upper tube, and at the same time reduce The error regulator voltage of the main circuit of the lower tube increases the pulse width of the upper tube and reduces the pulse width of the lower tube.

The first main power board includes a first input filter module, a transformer push-pull forward topology module, a full-bridge rectifier circuit, a peak absorption network module, and a first output filter module connected in sequence;

The PWM modulation circuit in the control circuit is connected with the transformer push-pull forward topology module through the drive circuit;

The second main power board includes a second input filter module, a flyback topology module, a second output filter module and an output protection module connected in sequence, and an input terminal of the flyback topology module and an output terminal of the output protection module are arranged There are control modules.

The first input EMI filter is used to filter the 110V of the locomotive, and provide the frequency signal for the push-pull forward topology of the subsequent transformer to work normally, so as to ensure the stability of the system.

The transformer push-pull forward topology module is used to realize two functions. On the one hand, it realizes the electrical isolation of input 110V and output 230V; It is converted into AC pulse wave and sent to the subsequent full-bridge rectifier circuit.

The full-bridge rectifier circuit is used to convert the pulse wave obtained by the transformer push-pull forward topology into a DC pulse wave.

The peak absorbing network module is used to realize two functions, on the one hand, smooth the DC pulse wave into a 230V DC output with small ripple; on the other hand, absorb the peak in the full bridge rectifier circuit and output smooth wave.

The first output EMI filtering module is used to implement EMI filtering on the output 230V and reduce the electromagnetic interference of the power supply to external electronic equipment.

The second input EMI filter module is used to filter the 110V of the locomotive, and provide the frequency signal for the back-stage flyback topology during normal operation to ensure the stability of the system.

The flyback topology module is used to realize two functions. On the one hand, it realizes the electrical isolation of input 110V and output 230V; Ripple DC 24V output.

The second output EMI filtering module is used to implement EMI filtering on the output 24V and reduce the electromagnetic interference of the power supply to external electronic equipment.

The output protection module is used to realize the electrical protection of the main power board 2 and external electronic equipment. When the output is over-current, a protection signal is generated and sent to the control circuit to complete the protection function.

As shown in FIG. 3 , it is a schematic diagram of the output characteristic test using the power converter of the present invention. Among them, the communication module provides reliable communication between the power supply and the external test process, and sends the working status of the power supply; the control communication module provides a transmission channel for the external control signal; the load module simulates various loads in the actual operation of the locomotive; the output acquisition module is responsible for the output of the power supply Quality analysis to judge whether the design requirements are met.

As shown in FIG. 4 , it is a schematic diagram of the application of the power converter according to the present invention to perform a dual power supply parallel test. Two of the tested power supplies adopt a direct parallel structure, and the communication module provides communication between the tested power supply and the external test process, and transmits the working status of the power supply; the control communication module provides a transmission channel for the external control signal; the load module simulates the actual operation of the locomotive. Various loads; the output acquisition module is responsible for analyzing the output quality of the power supply and judging whether it meets the design requirements.

This test performs a performance test on the module of the power supply, mainly for the test of power supply performance parameters.

The present invention realizes a power converter that satisfies power, volume, temperature and other requirements at the same time by studying all the basic requirements of the power converter of the electronically controlled air brake system of the locomotive, analyzing external power demand, power supply volume, temperature and other requirements;

In view of various situations that may occur outside the power supply of the train electronically controlled air brake system, the output voltage and current, input voltage and current are sampled, and hardware and software are used in the control circuit to judge whether the power supply has input and output overvoltage and overcurrent. phenomenon, turn off the PWM signal in time to achieve the corresponding protection purpose;

For all kinds of interference generated in the working environment of the power supply of the locomotive braking system, the method of adding input and output EMI filtering is adopted internally to achieve the purpose of suppressing electromagnetic interference;

Aiming at the unbalanced magnetic flux inside the power converter of the locomotive braking system, it is overcome by adding a magnetic flux balance regulator. Based on the above, the present invention realizes a power converter that meets the safety requirements of the train electronically controlled air brake system.

Claims (5)

1. A power converter for an electronically controlled air brake system, comprising a first main power board, a second main power board, a drive circuit, a control circuit and a switching circuit; The input end and the output end of the first main power board and the second main power board are respectively connected to the locomotive 110V power supply and the switching circuit through the locomotive power supply bus and PCB wiring; The locomotive 110V power supply, the first main power board and the drive circuit are connected to the control circuit through PCB wiring, control circuit bus and PWM output bus respectively; The output end of the drive circuit is connected to the first main power board; The switching circuit is connected to an external power load through a power output bus; The first main power board includes a first input filter module, a transformer push-pull forward topology module, a full-bridge rectifier circuit, a peak absorption network module, and a first output filter module connected in sequence; The PWM modulation circuit in the control circuit is connected with the transformer push-pull forward topology module through the drive circuit; The second main power board includes a second input filter module, a flyback topology module, a second output filter module and an output protection module connected in sequence, and an input terminal of the flyback topology module and an output terminal of the output protection module are arranged There is a control module. 2. The power converter for an electronically controlled air brake system according to claim 1, wherein the control circuit includes a control power supply, a current sampling module, a PWM modulation circuit, a magnetic flux balance regulator, an output protection module, a voltage sampling module and a main circuit error regulator; the control power supply is connected to the locomotive power supply and supplies power to the control circuit; The current sampling module collects two winding currents on the transformer push-pull forward topology module; The voltage sampling module collects the voltage on the output terminal of the first main power board; The current sampling module, the magnetic flux balance regulator and the PWM modulation circuit are connected in sequence; The voltage sampling module, the main circuit error regulator and the PWM modulation circuit are connected in sequence; The output end of the first main power board is connected to the PWM modulation circuit through the output protection module; The control circuit is connected with the switching circuit. 3. The power converter for an electronically controlled air brake system according to claim 2, wherein the magnetic flux balance regulator includes a differential module, a type-two error adjustment module, an inverting module, and a resistor divider network module; The differential module is connected to the current sampling module in the control circuit; The differential module, the type-two error adjustment module, the inverting module and the resistor divider network module are connected in sequence; The output end of the inverting module and the output end of the main circuit error regulator are all connected to the input end of the resistance voltage divider network module; The output terminal of the resistor divider network module is connected with the PWM modulation circuit. 4. The power converter for an electronically controlled air brake system according to any one of claims 1-3, wherein the drive circuit includes an optocoupler isolation module and a push-pull output module, and the optocoupler The isolation module is connected to the control circuit, and the push-pull output module is connected to the first main power board. 5. A magnetic flux balance adjustment method for a power converter of an electronically controlled air brake system, characterized in that, at first, two main power boards are used to communicate with the locomotive 110V power supply and switch through the locomotive power supply bus and PCB wiring respectively circuit connected; Secondly, the locomotive 110V power supply, the first main power board and the driving circuit are respectively connected to the control circuit through the PCB wiring, the control circuit bus and the PWM output bus, and the output end of the driving circuit is connected to the first main power board; The switching circuit is connected to an external power load through a power output bus; Set a flux balance regulator in the control circuit, use the flux balance regulator to perform differential processing on the two winding currents on the transformer in the first main power board, and input the signal data after differential processing to the second type error regulator The device obtains the current error adjustment value; Then, an inverter is used to invert the voltage of the type-two error regulator; Finally, use the resistor divider network to interconnect the signal after inversion processing, the current error adjustment value and the output signal of the main circuit voltage error regulator, thereby reducing or increasing the pulse width and realizing the balance adjustment of the power converter; The first main power board includes a first input filter module, a transformer push-pull forward topology module, a full-bridge rectifier circuit, a peak absorption network module, and a first output filter module connected in sequence; The PWM modulation circuit in the control circuit is connected with the transformer push-pull forward topology module through the drive circuit; The second main power board includes a second input filter module, a flyback topology module, a second output filter module, and an output protection module connected in sequence, and a control device is provided between the input end of the flyback topology module and the output end of the output protection module. module.