CN209948770U

CN209948770U - Voltage controller circuit of railway shaft end generator

Info

Publication number: CN209948770U
Application number: CN201920599221.3U
Authority: CN
Inventors: 刘星焱; 孙治国; 陈泳玖
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-04-28
Filing date: 2019-04-28
Publication date: 2020-01-14
Anticipated expiration: 2029-04-28

Abstract

The utility model belongs to the technical field of the locomotive power supply, a railway axle head generator voltage controller circuit is disclosed, a serial communication port, including the rectifier filter circuit of connecting the generator output, the steady voltage charging circuit who links to each other with rectifier filter circuit, the battery of being connected with steady voltage charging circuit, the discharge circuit who links to each other with the battery output and the load of being connected with discharge circuit. The BUCK structure of AC- > DC- > DC is used, and the work is stable and reliable. If the current and voltage algorithm uses an autonomously designed hardware operation mode, nanosecond-level response can be realized, and the microsecond-level response is far higher than the AD sampling microsecond-level response of a single chip microcomputer. The lowest ripple of the output voltage can be as low as 50mV, and the lowest ripple of the current can be as low as 100 mA. The feedback error is as low as 1mV, the import voltage reference is used, the extremely low temperature drift and the extremely high precision are far higher than the precision and the stability of the single chip AD.

Description

Voltage controller circuit of railway shaft end generator

Technical Field

The invention relates to the technical field of locomotive power supply, in particular to a voltage controller circuit of a generator at the end of a railway shaft.

Background

With the rapid development of electronic commerce in China, people have higher and higher requirements on logistics transportation timeliness, railway wagons can comprehensively speed up on the existing basis in order to expand transportation capacity and improve transportation timeliness, only locomotives of the existing railway wagons are powered, and later assembly carriages are not powered, are provided with air storage tanks and adopt compressed air for braking. The wheel is not easy to adjust and easy to cause locking, the dry friction between the train wheel and the rail is caused, the loss of the wheel is extremely large, and the wheel is not suitable for high-speed running. After the speed of a railway wagon is increased, an ABS (anti-lock brake system) needs to be adopted, so that power supply is required to be provided for each carriage, and the wagon carriages are often grouped and assembled, so that the power supply from a locomotive lead is unsafe and inconvenient. Each car is therefore equipped with batteries to provide power for the ABS anti-lock braking system, as well as the bearing monitoring system and lighting. However, the storage battery has limited stored electric quantity, which cannot meet the requirement of long-distance transportation, and if the transportation requirement is met and the capacity of the storage battery is increased, the cost is greatly increased, the occupied area is large, and the cargo capacity of each carriage is influenced.

Disclosure of Invention

The invention solves the technical problem of overcoming the defects of the prior art and provides a voltage control circuit of a railway axle end generator, which is characterized in that three-phase alternating current generated by a wheel axle end generator is rectified and stabilized by a generator voltage controller and then charges a storage battery, and the generator voltage controller has the function of input current limiting and can better protect the generator. The output belt is subjected to overcurrent protection, undervoltage protection, overvoltage protection and short-circuit protection, and the short-circuit protection belt is intermittently self-recovered, so that better battery protection and output protection are provided.

The technical scheme of the invention is as follows: a voltage controller circuit of a railway shaft end generator comprises a rectifying and filtering circuit connected with the output of the generator, a voltage-stabilizing charging circuit connected with the rectifying and filtering circuit, a storage battery interface connected with the voltage-stabilizing charging circuit, a discharging circuit connected with a storage battery interface and a load interface connected with the discharging circuit.

Furthermore, the rectification filter circuit is an uncontrollable rectification circuit, and the voltage-stabilizing charging circuit is a BUCK circuit.

Furthermore, an input current sampling circuit connected with the output of the rectification filter circuit is arranged between the rectification filter circuit and the voltage-stabilizing charging circuit, and the output of the input current sampling circuit is connected with the voltage-stabilizing charging circuit.

Still further, a charging current sampling circuit is connected in series between the voltage-stabilizing charging circuit and the storage battery.

Still further, a discharge current sampling circuit is connected in series between the discharge circuit and the load.

Furthermore, an input voltage detection circuit and a charging voltage detection circuit are also arranged in the rectification filter circuit and the voltage-stabilizing charging circuit; the voltage-stabilizing charging circuit and the storage battery are also provided with a temperature sampling circuit.

Furthermore, the outputs of the voltage detection unit circuit, the current sampling circuit and the temperature sampling unit circuit are also connected with the MCU chip.

Still further, the MCU chip is also connected with a display circuit and an external communication circuit.

Still further, the switching device of battery charge-discharge circuit is controlled by MCU chip.

Furthermore, the MCU chip is a singlechip, and the peripheral circuit of the singlechip is a minimum system.

Compared with the prior art, the invention has the following characteristics:

1) the BUCK structure of AC- > DC- > DC is used, and the work is stable and reliable.

2) If the current and voltage algorithm uses an autonomously designed hardware operation mode, nanosecond-level response can be realized, and the microsecond-level response is far higher than the AD sampling microsecond-level response of a single chip microcomputer. The lowest ripple of the output voltage can be as low as 50mV, and the lowest ripple of the current can be as low as 100 mA. The feedback error is as low as 1mV, the import voltage reference is used, the extremely low temperature drift and the extremely high precision (5 PPM) are far higher than the precision and the stability of the single chip AD.

3) The hardware and software compensate the constant temperature control algorithm of the power device, and the power device can be effectively protected. Can stably work in a higher temperature range.

4) The lower starting voltage requires that the minimum input direct current voltage can be as low as 24VDC, and the higher direct current voltage bearing range can bear direct current pulses of up to 200V.

5) MOS and diode adopt new import device, and reserve 2 times of allowance, use isolated MOS drive, intelligent MOS drive management, gather MOS tubulose condition immediately, can ensure more stable operating mode. The inductor uses a customized high-frequency inductor, and better EMI and power guarantee can be guaranteed.

6) The main control uses 32-bit MCU of ST, the main frequency operation is as high as 72Mhz, and the battery charging mode, the communication analysis and the like can be calculated more quickly. The temperature compensation is carried out strictly according to the battery charging management curve, the battery is managed intelligently, the charging current and voltage are adjusted in real time according to the battery state, the service life of the battery can be prolonged to the maximum extent, and the charging speed is higher.

7) The output belt is subjected to overcurrent protection, undervoltage protection, overvoltage protection and short-circuit protection, and the short-circuit protection belt is intermittently self-recovered, so that better battery protection and output protection are provided.

8) The Modbus communication protocol of the industrial standard is used, and the isolation type 485 communication chip of the AD company is used, so that the Modbus communication protocol has wider adaptability and higher anti-interference and stability.

The detailed structure of the present invention will be further described with reference to the accompanying drawings and the detailed description.

Drawings

Fig. 1 is a circuit block diagram of a railway axle end generator voltage controller of embodiment 1;

FIG. 2 is a circuit for rectifying, filtering and sampling an input current according to embodiment 1;

fig. 3 shows the voltage-stabilized charging and driving circuit of embodiment 1;

fig. 4 is a charging current sampling circuit in embodiment 1;

FIG. 5 is a battery discharge circuit in embodiment 1;

FIG. 6 is a MCU minimum system of embodiment 1;

FIG. 7 is a temperature measuring circuit of embodiment 1;

fig. 8 is an RS485 communication circuit of embodiment 1;

FIG. 9 is a man-machine interaction circuit of embodiment 1;

fig. 10 is an external control interface of embodiment 1;

fig. 11 is a control power supply circuit of embodiment 1;

fig. 12 is a driving power supply circuit of embodiment 1.

Detailed Description

Example 1

The voltage controller of the railway shaft end generator has multiple functions, is complex in schematic diagram and convenient to read and understand, the functional structure is taken as a unit for explanation, and the connection schematic diagram of each functional unit is shown in fig. 1. The power supply circuit provides power for active devices of the main circuit and the control circuit, and ensures that the whole system can normally run;

the main circuit comprises a rectifying filter circuit connected with the output end of the generator, an input current sampling circuit connected with the rectifying filter circuit, an input voltage detection circuit connected with the input current sampling circuit, a voltage-stabilizing charging circuit connected with the input voltage detection circuit, an output current sampling circuit connected with the voltage-stabilizing charging circuit, a charging voltage detection circuit connected with the output current sampling circuit, a charging current sampling circuit connected with the charging voltage detection circuit, a storage battery interface connected with the charging current sampling circuit, a discharging circuit connected with the storage battery interface, a discharging current sampling circuit connected with the discharging circuit and a load interface connected with the discharging current; in addition, the temperature measuring circuit is respectively connected with the voltage-stabilizing charging circuit and the storage battery, and the driving circuit is connected with the voltage-stabilizing charging circuit.

The control circuit comprises an MCU (microprogrammed control unit) for sampling and measuring voltage, current and temperature sampling signals and a minimum system thereof, an external communication circuit connected with the MCU, a display circuit connected with the MCU, a temperature measuring circuit connected with the MCU and an external control interface connected with the MCU.

The power supply circuit comprises various levels of power supply voltage circuits consisting of various DC/DC power supply chips and LDOs, a control power supply circuit for providing proper control power supply for various chips in the main circuit and the control circuit, and a driving power supply circuit for supplying power to the power tube driver of the voltage-stabilizing charging circuit.

The rectifying, filtering, input current sampling and input voltage detecting circuit is shown in fig. 2, wherein the input of a rectifier bridge is connected with an output interface of an end-of-shaft generator, alternating current of the end-of-shaft generator is converted into direct current after passing through the rectifier bridge, overcurrent protection is performed through a melt F1, the melt is connected with an input current sampling chip U1, then the rectified pulse waveform is smoothed through filter capacitors C1, C2 and C3, and the voltage value of the filtered direct current voltage is detected in a resistance voltage dividing mode.

Specifically, the rectifier bridge adopts an uncontrollable rectifier bridge, a current signal output by an input current sampling chip U1 is converted into a voltage signal through a resistor, an input current sampling signal TIN after RC filtering is sent to the MCU, and an input voltage sampling signal ADC _ IN7 after RC filtering is sent to the MCU after a small resistor is connected IN parallel to a capacitor to filter voltage spikes and other interference.

More specifically, the uncontrollable rectifier bridge adopts a glass passivated three-phase uncontrollable bridge rectifier with a Microsmi model number of 3GBJ3508, and the uncontrollable rectifier bridge has the advantages of reduced forward voltage, strong current capacity, high surge current capacity and high reliability; the voltage output by the uncontrollable rectifier bridge after filtering is 400V direct current; the melt adopts the specification of 20A/600V; the current sampling chip adopts an Allegro current amplification chip with the model of ACS 758. The filter capacitors C2, C3 and C4 adopt high-frequency high-temperature long-life inlet capacitors, better ripple waves and EMI are guaranteed, resistors R7 and a TVS tube D3 are connected behind the filter capacitors C2, C3 and C4, the output voltage of the rectifier circuit can be effectively prevented from being increased when the rectifier circuit is in no-load, the filter capacitors serve as discharge resistors of the capacitors when the rectifier circuit is powered off, and possible contact and electric shock risks are avoided.

As shown in fig. 3, the voltage-stabilizing charging circuit adopts a BUCK structure, and reduces the 400V dc voltage after the preceding stage rectification to a stable 28V dc voltage for charging the storage battery; the BUCK circuit is connected with an output current sampling chip U2, and an output current sampling signal is filtered by a capacitor C11 and then sent to the MCU for processing.

Specifically, the power device of the BUCK circuit adopts a mode that MOS tubes are connected in parallel, and the through-current capacity of the circuit is improved. MOS transistor Q1 and Q2 gate signals are directly connected in parallel, so that the difference of driving signals is further reduced; a fly-wheel diode of the BUCK circuit is formed by connecting two dual-port diodes D4 and D13 in parallel, so that the through-current capacity of the circuit is improved; the driving circuit adopts an intelligent driving chip; and the MOS tube and the RC absorption circuit connected with the two ends of the freewheeling diode in parallel effectively absorb voltage spikes and protect the semiconductor device. The output end is parallelly connected with resistance R9, R10, electric capacity C7 and TVS pipe D10 and D11, output voltage lifting when the rectifier circuit can effectively be avoided to resistance and TVS pipe unloaded to and act as the discharge resistance of electric capacity when the outage, avoid possible contact electric shock risk, electric capacity C7 can absorb the high frequency ripple among the BUCK circuit output voltage, control circuit can realize overflowing and short-circuit protection function according to sampling output current, prevent that the mistake of power tube among the BUCK circuit from leading to and damaging the circuit.

More specifically, a MOS transistor with the model of AUIRFP4409 and a diode with the model of MUR3060PTG are all new inlet devices, and 2 times of allowance is reserved. Isolated MOS drive and intelligent MOS drive management are selected, MOS tubular conditions are collected in real time, and more stable working conditions can be guaranteed; inductor L1 uses a custom high frequency inductor to provide better EMI and power protection.

As shown in figure 4, the output voltage of the BUCK circuit passes through diodes D1 and D2 and then is filtered and stabilized, then the charging current of the storage battery is sampled through the charging current sampling circuit, meanwhile, the charging voltage is detected in a resistance voltage division mode, and then the charging current is filtered through a capacitor C5 and then is directly connected to the battery for charging.

Specifically, the diodes D1 and D2 are anti-backflow diodes to prevent the current from discharging in the reverse direction when the voltage of the front stage is low, and R6 is a discharge resistor.

As shown in figure 5, a discharge circuit of the storage battery is characterized in that an MOS tube Q8 connected with the anode of the storage battery can control the discharge depth of the storage battery, a current sampling chip U15 connected with the MOS tube samples the discharge current of the storage battery, the discharge current is sent to an MCU after being filtered by an RC, and the output of the current sampling chip U15 is directly connected with a load interface.

Specifically, the MOS transistor Q8 is driven by two stages of amplification by the transistors Q10 and Q9. And the load interface side is also connected with a light-emitting diode which is used for displaying the discharge state of the battery. The control circuit carries out calculation and logic judgment according to the voltage and the discharge current of the battery and controls the working state of the discharge circuit so as to realize overcurrent, overdischarge and undervoltage protection of the battery;

the core in the control circuit is an MCU and its minimum system, as shown in fig. 6 specifically; the MCU analyzes and calculates each voltage, current and temperature sampling signal in the main circuit to realize the control and various logic protection of the main circuit;

specifically, the MCU uses a 32-bit CPU with the ST model of STM320F100C4, the main frequency operation reaches up to 72Mhz, and the battery charging mode, the communication analysis and the like can be calculated more quickly;

the temperature measuring circuit of the MOS tube and the storage battery in the voltage-stabilizing charging circuit is shown in FIG. 7;

specifically, the MCU strictly performs temperature compensation according to a battery charging management curve according to the temperature of the storage battery, intelligently manages the battery, and immediately adjusts charging current and voltage according to the state of the battery, so that the service life of the battery can be prolonged to the maximum extent, and the charging speed is higher. The hardware and software compensate the constant temperature control algorithm of the power device, can effectively protect the power device, and can stably work in a higher temperature range.

The external communication circuit is shown in fig. 8; and RS485 is adopted for external communication to send various real-time data and logic states of the circuit to an upper computer and receive related instructions of the upper computer to control the circuit.

Specifically, an industrial standard Modbus communication protocol is used for external communication, and an isolated 485 communication chip of an AD company is used, so that the device has wider adaptability and higher anti-interference and stability.

As shown in fig. 9, the human-computer interaction circuit includes an external indication interface circuit and a state display circuit;

specifically, the external indication interface circuit not only displays the logic processing result of the MCU through the four light emitting diodes, but also transmits the state to an external circuit through the interface socket; the state display circuit displays the running state of the circuit through three light-emitting diodes;

the external control interface is shown in fig. 10, and is connected to the upper-level core computing module;

specifically, pulse calculation of the BUCK circuit MOS tube is controlled by a core calculation module at the upper stage, pulse signals of the MOS tubes Q1 and Q2 are calculated by sampling a battery charging voltage, the output current of the BUCK circuit, the temperature of a power board and an input current signal, and are sent to the driving chip U4.

The control power supply circuit is shown in fig. 11, and has two power taking points, (1) power is taken from the output of a rectifier bridge of a rectifier filter circuit, the front-level power is reduced to 15V after passing through a power chip U5, and the VCC voltage is stabilized at 15V through a filter and a voltage stabilizing diode. (2) Taking power from a storage battery, and converting 24V into 15V voltage through an LDO chip; two 15V power supplies are connected in parallel with a D35 through a diode D26 to form a 15V power supply VCD of the whole system; the 3.3V power supply VDD is converted from a 15V power supply through the LDO chip U8; the 3.0V analog power supply VDDA is generated by VDD through a high-precision reference voltage chip U11 power supply;

as shown in fig. 12, the driving power supply circuit obtains power from VCD at the output of the BUCK circuit, converts the power into a 15V power VCC through LDO chip U6, and generates 15V isolated driving power VBB and VEE through 15V isolated power chip U7 after filtering and melt overcurrent protection, where VEE is the negative electrode of the driving power supply; the isolated power chip U9 is its redundant backup chip.

The present invention is not limited to the above-mentioned specific structures or connection manners, and it is within the scope of the present invention to have substantially the same structure or connection manners as the concept of the present invention.

Claims

1. A voltage controller circuit of a generator at the end of a railway shaft is characterized by comprising a rectifying and filtering circuit connected with the output of the generator, a voltage-stabilizing charging circuit connected with the rectifying and filtering circuit, a storage battery interface connected with the voltage-stabilizing charging circuit, a discharging circuit connected with the storage battery interface and a load interface connected with the discharging circuit.

2. The railway shaft end generator voltage controller circuit as claimed in claim 1, wherein the rectifying and filtering circuit is an uncontrollable rectifying circuit, and the voltage-stabilizing and charging circuit is a BUCK circuit.

3. The voltage controller circuit of the railway shaft end generator as claimed in claim 1 or 2, wherein an input current sampling circuit connected with the output of the rectifying and filtering circuit is further arranged between the rectifying and filtering circuit and the voltage-stabilizing charging circuit, and the output of the input current sampling circuit is connected with the voltage-stabilizing charging circuit.

4. The railway shaft end generator voltage controller circuit as claimed in claim 3, wherein a charging current sampling circuit is connected in series between the voltage-stabilizing charging circuit and the storage battery.

5. The railway end-of-axle generator voltage controller circuit of claim 4, wherein a discharge current sampling circuit is connected in series between the discharge circuit and the load interface.

6. The railway shaft end generator voltage controller circuit as claimed in claim 1, wherein the rectifying filter circuit and the voltage-stabilizing charging circuit are further provided with an input voltage detection circuit and a charging voltage detection circuit; the voltage-stabilizing charging circuit and the storage battery are also provided with a temperature sampling circuit.

7. The railway shaft end generator voltage controller circuit as claimed in claim 6, wherein the outputs of the voltage detection unit circuit, the current sampling circuit and the temperature sampling unit circuit are further connected with the MCU chip.

8. The railway shaft end generator voltage controller circuit as claimed in claim 7, wherein the MCU chip is further connected to the display circuit and the external communication circuit.

9. The railway shaft end generator voltage controller circuit as claimed in claim 8, wherein the switching device of the battery charging and discharging circuit is controlled by the MCU chip.

10. The voltage controller circuit of the generator at the end of the railway shaft as claimed in any one of claims 7 to 9, wherein the MCU chip is a single chip microcomputer, and a peripheral circuit of the single chip microcomputer is a minimum system.