CN211480932U

CN211480932U - Voltage control system for comprehensive protection device

Info

Publication number: CN211480932U
Application number: CN201922379961.9U
Authority: CN
Inventors: 李滨; 张俊; 杨亮
Original assignee: Jiangsu Delphi Intelligent Technology Co ltd
Current assignee: Jiangsu Delphi Intelligent Technology Co ltd
Priority date: 2019-12-26
Filing date: 2019-12-26
Publication date: 2020-09-11
Anticipated expiration: 2029-12-26

Abstract

The utility model discloses a voltage control system for an integrated protection device, which comprises a three-phase power switch, a direct current chain supporting capacitor, a high-voltage switch, a voltage measuring circuit and a microcontroller; the three-phase power switch is controlled by the PWM signal output by the signal control unit to drive a three-phase load; the direct current chain supporting capacitor is connected in parallel with two ends of the three-phase power switch and is connected with a voltage supply end of the battery to supply the running voltage of the three-phase load or the counter electromotive force of the three-phase load is supplied to the voltage supply end to charge the battery; the high-voltage switch is connected between the direct-current chain support capacitor and the reference potential end in series and is provided with a control end; a voltage measuring circuit connected to the voltage supply terminal for measuring a voltage on the voltage supply terminal; microcontroller connects at voltage measurement circuit's output and high voltage switch's control end, judges the voltage of battery, the utility model discloses a control voltage protects the load for load operation safe and reliable more.

Description

Voltage control system for comprehensive protection device

Technical Field

The utility model relates to a voltage control device, in particular to voltage control system for integrated protection device.

Background

The stability of voltage can ensure the normal operation of various electrical equipment and prolong the service life thereof, the voltage qualification rate becomes a main concern of users along with the increasing demand of the users on the power supply quality, the reactive power can not be remotely transmitted in the power grid for the consideration of economy so as to avoid the energy loss caused by the remote transmission of the reactive power as much as possible, the realization of the voltage reactive power optimization control in the power system has wide and important economic benefit and social benefit, the reactive voltage control device used by the existing substation gives control measures according to the position on the operated regional diagram, the internal voltage requirement and the reasonable distribution of the reactive power of the substation are met, but the existing reactive voltage control device can only realize the local optimization, can not realize the optimization control of the whole system, and only can ensure the voltage of the controlled bus to be qualified, the purpose of reducing the power loss of the whole network cannot be achieved.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a voltage control system for integrated protection device protects the load through control voltage.

The purpose of the utility model is realized like this: a voltage control system for an integrated protection device comprises a three-phase power switch, a direct-current chain supporting capacitor, a high-voltage switch, a voltage measuring circuit and a microcontroller;

the three-phase power switch is controlled by the PWM signal output by the signal control unit to drive a three-phase load;

the direct current chain supporting capacitor is connected in parallel to two ends of the three-phase power switch and is connected with a voltage supply end of a battery to supply the running voltage of the three-phase load or is supplied by the back electromotive force of the three-phase load to the voltage supply end to charge the battery;

the high-voltage switch is connected between the direct-current chain supporting capacitor and a reference potential end in series and is provided with a control end;

the voltage measuring circuit is connected to the voltage supply end and used for measuring the voltage on the voltage supply end;

the microcontroller is connected with the output end of the voltage measuring circuit and the control end of the high-voltage switch, judges the voltage of the battery, and outputs a cut-off signal to the control end when the voltage exceeds a protection voltage value so as to open the high-voltage switch to cut off the connection between the voltage supply end and the battery; the microcontroller is operated in a normal mode, measures whether the voltage of the battery is in a full-power state or not for a load normal running state, outputs a potential signal value, when the potential signal value is smaller than the protection voltage value, the back electromotive force of the three-phase load can charge the battery, and when the potential signal value is larger than the protection voltage value, the cut-off signal is output to the control end of the high-voltage switch so as to cut off the charging connection of the back electromotive force of the three-phase load to the battery.

As a further limitation of the present invention, the three-phase power switch is a three-phase MOSFET or an Insulated Gate Bipolar Transistor (IGBT).

As a further limitation of the present invention, the dc link supporting capacitor is formed by connecting a plurality of capacitors in series.

As a further limitation of the present invention, the high voltage switch is a switch control circuit composed of a MOSFET or a relay.

As a further limitation of the present invention, the reference potential terminal is a ground terminal.

As a further limitation of the present invention, the microcontroller and the voltage measurement circuit are further provided with an isolator therebetween.

As a further limitation of the invention, the protection voltage value is set by the microcontroller.

Compared with the prior art, the beneficial effects of the utility model reside in that: the utility model discloses but the shutdown state still automatic monitoring voltage awakens up microcontroller and gets into the protection mode, in addition the utility model discloses can avoid the counter electromotive force voltage too high, damage the condition of load and take place.

Drawings

Fig. 1 is a schematic circuit diagram of an embodiment of a voltage control device with an automatic measurement function.

Fig. 2 is a schematic view of the automatic voltage measurement control process of the present invention.

Fig. 3 is a schematic diagram of the flow of executing weak magnetic control of the present invention.

Fig. 4 is a schematic diagram of the single-phase control process of the present invention.

Detailed Description

The present invention will be further described with reference to the following specific embodiments.

Fig. 1-4 show a voltage control system for an integrated protection device, which includes a signal control unit 20, a voltage control unit 30, a three-phase power switch 10 and a battery BT314, wherein the signal control unit 20 further includes a microcontroller MCU21, a driving circuit 22 and a voltage regulator U223, and the voltage control unit 30 further includes an electric dc link supporting capacitor 13, a voltage measuring circuit 31, a comparator U1a32 and a high voltage switch 40.

The utility model discloses during with the software control, wherein microcontroller MCU21 in the signal control unit 20 can export a PWM signal, connect at three-phase power switch 10 through drive circuit 22, be used for driving three-phase power switch 10 drive three-phase load 12, direct current chain supports electric capacity 13 and connects in parallel at three-phase power switch 10, and more connect at a voltage supply end HV, voltage supply end HV then connects battery BT314, be used for supplying three-phase load 12 running voltage, or supply to voltage supply end HV by three-phase load 12's back electromotive force and charge to battery BT 314.

Wherein the high voltage switch 40 is connected between the dc link supporting capacitor 13 and the battery 14, the high voltage switch 40 includes a control terminal connected to the microcontroller MCU21 of the signal control unit 20, and is controlled by the microcontroller MCU21 to be opened or turned on, when turned on, the dc link supporting capacitor 13 is connected in parallel to the battery 14, wherein the voltage measuring circuit 31 is connected to the voltage supply terminal HV for measuring the voltage at the voltage supply terminal HV, and is output to the microcontroller MCU21 through a first isolator 34, when the microcontroller MCU21 determines that the voltage at the voltage supply terminal HV exceeds a protection voltage Vn, a cut-off signal HV CTL is output to the control terminal of the high voltage switch 40, so that the high voltage switch 40 is opened to cut off the dc link supporting capacitor 13 connected in parallel to the battery 14, i.e. to cut off the charging connection between the battery 314 and the three-phase load 12, and vice versa, when the voltage at the voltage supply terminal HV does not exceed the protection voltage Vn, the high voltage switch S140 is turned on and the battery BT314 is connected in parallel to the dc link support capacitor 13, i.e. the battery BT314 is connected in parallel between the three-phase loads 12. Wherein the protection voltage value Vn is set by the microcontroller MCU 21.

When the battery BT314 supplies power to the three-phase load 12, the signal control unit 20 outputs the PWM signal to control the three-phase power switch 10 to drive the three-phase load 12 to operate, and when the three-phase load 12 is switched to the power generation mode, the voltage generated by the back electromotive force can charge the battery BT314, but if the battery BT314 is in a full power state and charging is not allowed, the voltage generated by the back electromotive force is too high when the three-phase load 12 operates in the power generation mode and without load, which may cause the three-phase power switch 10 to be damaged.

Therefore, the present invention utilizes the high voltage switch 40 to connect between the dc link supporting capacitor 13 and the battery 14, preferably, the high voltage switch 30 is connected between the grounding terminal GNDC of the dc link supporting capacitor 13 and the grounding terminal GNDHV of the battery 14, the voltage measuring circuit 31 can measure the voltage of the battery BT314 on the voltage supply terminal HV, when the voltage of the battery BT314 exceeds a protection voltage value Vn, a cut-off signal HV CTL is outputted to the control terminal of the high voltage switch 40, so that the high voltage switch 40 is opened, so as to cut off the parallel connection between the voltage supply terminal HV and the battery BT314, and the load driving circuit cannot be damaged by the over-high voltage.

In the present embodiment, the output of the lithium battery of the battery BT314 is high-voltage direct current. And the three-phase power switch 10 may be a three-phase MOSFET or an insulated gate bipolar transistor IGBT. The DC-link supporting capacitor 13 is formed by serially connecting a plurality of capacitors C1 n-Cnn. And the high voltage switch 40 may be a switch control circuit formed by a MOSFET or a relay.

The utility model discloses when protecting with the hardware, wherein the utility model discloses a voltage measurement circuit 31 of voltage control unit 30 is connected at voltage supply end HV for measure battery BT 314's voltage, output a potential signal value V1, whether comparator U1A32 comparison potential signal value V1 exceeds a settlement potential value VTH, if exceed, then enable stabiliser U223 through a second isolator 35 output signal WK _ HV.

The comparator U1A33 comprises a first comparing terminal connected to the voltage measuring circuit 31 for receiving the voltage signal V1, a second comparing terminal connected to a set voltage value VTH, and an output terminal for outputting a high voltage signal WK _ HV when the voltage signal V1 is greater than the set voltage value VTH and outputting a low voltage signal. The voltage stabilizer U223 includes an output control end CTL connected to an output end of the comparator U1a32, when the comparator U1a32 outputs a high-level signal WK _ HV, an output end OUT of the voltage stabilizer U223 outputs a working voltage + VDD to provide operating power for the microcontroller MCU21 and other circuits, and when the comparator U1a31 outputs a low-level signal, the voltage stabilizer U223 turns off the output of the working voltage + VDD to enable the microcontroller MCU21 to enter a power-off sleep state.

Wherein the set potential value VTH is converted into a circuit voltage + Vcc by the voltage supply terminal HV through the DC converter 33, and is formed by dividing the voltage by the two resistors R1, R3, and the set potential value VTH can be determined by adjusting the divided resistance value of the two resistors R1, R3. The voltage regulator U223 is supplied with power from a system battery BT1 mounted on the vehicle, and converts the power to a stable operating voltage + VDD. The output control end CTL of the voltage regulator U223 is further connected to a start power signal V _ IGN, when the vehicle is started, the start power signal V _ IGN is at a high potential, which indicates that the vehicle is in a power-on state, and at this time, the voltage regulator U223 outputs a working voltage + VDD.

The utility model discloses a microcontroller MCU21 can operate in normal mode or initiative protection mode, and wherein microcontroller MCU21 operates for load normal operating condition in normal mode. When the load is in the start-up state, the start-up power signal V _ IGN is at the high level ONS401, and the microcontroller MCU21 starts S402 the normal mode. If the power-up signal V _ IGN is low, but the comparator U1A32 outputs a high normal signal WK _ HV S403, the microcontroller MCU21 similarly starts S402 normal mode. If the power-up signal V _ IGN is at a low level and the comparator U1a32 outputs an abnormal signal that is also at a low level, it indicates that the microcontroller MCU21 is in a sleep state with power off.

When the microcontroller MCU21 starts S402 normal mode, it measures whether the voltage of the battery BT314 is in an excessively high state, and when the potential signal value V1 is smaller than the protection voltage value Vn, S404 indicates that the battery voltage is normal, it controls the high voltage switch S1 to turn on S405, and then the process goes to the subsequent step S410, where the back emf of the three-phase load 12 can charge the battery BT 314. When the potential signal value V1 is greater than the protection voltage value Vn plus the hysteresis voltage Δ V, S406 indicates that the voltage level of the battery is too high, the high-voltage switch S1 is controlled to open the circuit S407, so as to cut off the damage of the battery to the load driver. The battery BT114 cannot be charged by the counter electromotive force of the three-phase load 12 at this time. If the load is still running, the microcontroller MCU21 enters the active voltage control mode S408 to immediately reduce the voltage to protect the three-phase power switch 10 and the dc link supporting capacitor 13 from overvoltage damage. If the potential signal value V1 is greater than the protection voltage value Vn but less than the protection voltage value Vn plus the hysteresis voltage Δ V, the high-voltage switch S1 is also controlled to turn on S409, and the process proceeds to the subsequent step S410.

When the microcontroller MCU21 operates in the active protection mode, the start power signal V _ IGN is at the low potential Off, the voltage regulator U223 does not output the working voltage + VDD, and the microcontroller MCU21 is in the power-Off state, but the voltage value of the voltage supply terminal HV is greater than the set potential value VTH due to the back emf of the three-phase load 12, so the voltage regulator U223 outputs the working voltage + VDD to start the microcontroller MCU22, for the vehicle is in the high-speed towing state or the vehicle is in the high-speed driving state when the power is turned Off.

Fig. 3 is a schematic diagram of the flux weakening control process executed by the active voltage control according to the present invention, and the Id is determined according to the speed of voltage drop and the allowable range. Fig. 4 is a schematic diagram of the single-phase control process executed by the active voltage control of the present invention, such as S1 ON, S4, S6 ON, and Duty is determined according to the voltage drop. Similarly, S3, S2, S6 and S5, S2, S4 are combined.

The present invention is not limited to the above embodiments, and based on the technical solutions disclosed in the present invention, those skilled in the art can make some replacements and modifications for some technical features without creative labor, and these replacements and modifications are all within the protection scope of the present invention.

Claims

1. A voltage control system for an integrated protection device is characterized by comprising a three-phase power switch, a direct-current chain supporting capacitor, a high-voltage switch, a voltage measuring circuit and a microcontroller;

2. The voltage control system of claim 1, wherein the three-phase power switch is a three-phase MOSFET or an Insulated Gate Bipolar Transistor (IGBT).

3. The voltage control system of claim 1, wherein the dc-link supporting capacitor is formed by serially connecting a plurality of capacitors.

4. The voltage control system of claim 1, wherein the high voltage switch is a switch control circuit formed by a MOSFET or a relay.

5. The voltage control system according to claim 1, wherein the reference potential terminal is a ground terminal.

6. The voltage control system of claim 1, further comprising an isolator between the microcontroller and the voltage measurement circuit.

7. The voltage control system of claim 1, wherein said protection voltage value is set by said microcontroller.