CN220439493U - Control circuit of contactor - Google Patents

Abstract

The utility model discloses a control circuit of a contactor, which comprises a power supply module, a switch executing module, a contactor coil module and a control circuit module. The input end of the power supply module is electrically connected with a power supply, and the power supply module is used for carrying out voltage conversion on the power supply voltage. The contactor coil module comprises an electromagnetic coil, the switch executing module comprises a switch unit, and the electromagnetic coil and the switch unit are connected in series between the output end and the grounding end of the power supply module. The power supply end of the control circuit module is electrically connected with the power supply module, and the output end of the control circuit module is electrically connected with the control end of the switch executing module. The control circuit module is used for carrying out energy storage charge and discharge, conversion of logic signals and logic operation on the input voltage signals and outputting PWM control signals so as to control the on or off of the switch unit and further control the on or off of the contactor. The technical scheme provided by the embodiment of the utility model can simplify the circuit structure and improve the real-time performance of contactor control.

Description

Control circuit of contactor

Technical Field

The utility model relates to the technical field of circuits, in particular to a control circuit of a contactor.

Background

The contactor has wide application, and the working principle is that the contactor directly inputs alternating current or direct current to the coil, and after the coil is electrified, the lower iron core generates magnetic force to enable the upper iron core to overcome the elastic force of the spring, and then the movable contact is driven to move to contact with the fixed contact.

The coil of the traditional alternating current contactor maintains high power consumption, and in the prior art, a PWM control signal is generated in a software mode, and the coil is controlled by the PWM control signal, so that the energy consumption of the coil can be reduced; the other is that the low-resistance winding plays a main role in the actuation starting process in a double-winding coil switching mode, and the high-resistance winding plays a main role in a holding state, so that the energy-saving purpose is realized. However, the former hardware part needs a micro controller chip, a peripheral circuit and a driving circuit to realize, the circuit design is complex, and in use, the running of a software program needs execution time, so that the real-time performance is poor; the latter has a problem in that the double coil is difficult to wind.

Disclosure of Invention

The utility model provides a control circuit of a contactor, which is used for simplifying a circuit structure and improving the real-time performance of contactor control.

According to an aspect of the present utility model, there is provided a control circuit of a contactor, comprising:

The input end of the power supply module is electrically connected with a power supply, and the power supply module is used for carrying out voltage conversion on the power supply voltage;

the switch executing module comprises a switch unit, and the electromagnetic coil and the switch unit are connected in series between the output end and the grounding end of the power supply module;

the control circuit module is electrically connected with the power supply module at the power supply end, and the output end of the control circuit module is electrically connected with the control end of the switch execution module; the control circuit module is used for carrying out energy storage charge and discharge, conversion of logic signals and logic operation on the input voltage signals and outputting PWM control signals so as to control the on or off of the switch unit and further control the on or off of the contactor.

According to the technical scheme provided by the embodiment of the utility model, the control circuit module is arranged in the contactor control circuit, and can perform logic operation and energy storage charge and discharge on an input voltage signal and output a PWM control signal with a certain duty ratio and control period. Because the logic operation and the energy storage charging and discharging functions can be realized through a hardware circuit, compared with the prior art, the technical scheme of the embodiment of the utility model can realize the control of the working state of the contactor by adopting the hardware circuit without adopting software programming. Therefore, the technical scheme of the embodiment of the utility model is beneficial to simplifying the circuit structure and improving the real-time performance of contactor control.

It should be understood that the description in this section is not intended to identify key or critical features of the embodiments of the utility model or to delineate the scope of the utility model. Other features of the present utility model will become apparent from the description that follows.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the drawings required for the description of the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present utility model, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic structural diagram of a control circuit of a contactor according to an embodiment of the present utility model;

FIG. 2 is a schematic circuit diagram of a power module according to an embodiment of the present utility model;

FIG. 3 is a schematic circuit diagram of a control circuit module according to an embodiment of the present utility model;

fig. 4 is a schematic circuit diagram of a control circuit module according to an embodiment of the present utility model;

FIG. 5 is a schematic circuit diagram of another control circuit module according to an embodiment of the present utility model;

Fig. 6 is a schematic circuit diagram of a connection between a switch executing module and a contactor coil module according to an embodiment of the present utility model;

fig. 7 is a flowchart of a method executed by a control circuit of a contactor according to an embodiment of the present utility model.

Detailed Description

In order that those skilled in the art will better understand the present utility model, a technical solution in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in which it is apparent that the described embodiments are only some embodiments of the present utility model, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present utility model without making any inventive effort, shall fall within the scope of the present utility model.

It should be noted that the terms "first," "second," and the like in the description and the claims of the present utility model and the above figures are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that the embodiments of the utility model described herein may be implemented in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

Fig. 1 is a schematic structural diagram of a control circuit of a contactor according to an embodiment of the present utility model, and referring to fig. 1, the control circuit includes a power module 1, a switch execution module 4, a contactor coil module 5, and a control circuit module 3. The input end of the power supply module 1 is electrically connected with the power supply 2, and the power supply module 1 is used for carrying out voltage conversion on the power supply voltage. The contactor coil module 5 includes an electromagnetic coil 51, and the switch execution module 4 includes a switch unit 41, and the electromagnetic coil 51 and the switch unit 41 are connected in series between the output terminal of the power supply module 1 and the ground terminal GND. The power supply end of the control circuit module 3 is electrically connected with the power supply module 1, and the output end of the control circuit module 3 is electrically connected with the control end of the switch execution module 4. The control circuit module 3 is configured to perform energy storage charging and discharging, conversion of logic signals, and logic operation on the input voltage signal, and output a PWM control signal 1Y to control on or off of the switching unit 41, thereby controlling on or off of the contactor.

The power supply source provides alternating current, and the electromagnetic coil and the control circuit module require direct current. The working principle of the control circuit is that the power supply module 1 rectifies alternating current provided by the power supply 2 into direct current and outputs a voltage signal of the direct current to the control circuit module 3 and the contactor coil module 5. The control circuit module 3 performs energy storage charging and discharging by using the voltage signal, and controls the time of charging and discharging by performing conversion and logic operation of logic signals on the voltage signal, thereby outputting a PWM control signal 1Y with a certain duty ratio and control period to the switch executing module 4. The control terminal of the switch executing module 4 is connected to the PWM control signal 1Y, so as to control the switch unit 41 to be turned on or off. When the switch unit 41 is turned on, the electromagnetic coil 51 connected in series with the switch unit is powered on, and the contactor is closed; when the switching unit 41 is turned off, the electromagnetic coil 51 connected in series therewith is deenergized, and the contactor is opened.

In the technical scheme of the embodiment, a control circuit module 3 is arranged in a contactor control circuit, and the control circuit module 3 can perform logic operation and energy storage charge and discharge on an input voltage signal and output a PWM control signal 1Y with a certain duty ratio and control period. Because the logic operation and the energy storage charging and discharging functions can be realized through a hardware circuit, compared with the prior art, the embodiment of the utility model can realize the control of the working state of the contactor by adopting the hardware circuit without adopting software programming. Therefore, the technical scheme of the embodiment is beneficial to simplifying the circuit structure and improving the real-time performance of contactor control.

With continued reference to fig. 1, on the basis of the above embodiments, optionally, the power module 1 includes: a power protection unit 11, a rectifying and filtering unit 12 and a voltage stabilizing and filtering unit 13.

The input end of the power protection unit 11 is used as the input end of the power module 1, and the output end of the power protection unit 11 is connected with the input end of the rectifying and filtering unit 12. The power protection unit 11 is used for protecting the power module 1 and filtering electromagnetic interference. The protection type can be overvoltage protection, overcurrent protection, lightning protection and the like; the electromagnetic interference can be the interference of the high-frequency pulse of the external power network, the electromagnetic interference of the control circuit module 3, and the like.

The output end of the rectifying and filtering unit 12 is electrically connected with the input end of the voltage stabilizing and filtering unit 13, and the output end of the rectifying and filtering unit 12 is electrically connected with the contactor coil module 5. The rectifying and filtering unit 12 is used for converting alternating current into direct current and supplying power to the voltage stabilizing and filtering unit 13 and the contactor coil module 5.

The output end of the voltage stabilizing filter unit 13 is electrically connected with the control circuit module 3. The voltage stabilizing and filtering unit 13 is used for stabilizing and filtering the input direct current and supplying power to the control circuit module 3.

The voltage signal output by the voltage stabilizing and filtering unit 13 is more stable and more suitable for the control circuit module 3 than the voltage signal output by the rectifying and filtering unit 12. Therefore, the voltage stabilizing filter unit 13 is arranged in the power module 1, which is beneficial to improving the stability of the control circuit.

In addition, in the present embodiment, by providing the power supply protection unit 11, the rectifying and filtering unit 12, and the voltage stabilizing and filtering unit 13 in the power supply module 1, the alternating-current voltage supplied from the power supply 2 is converted into direct current, and electromagnetic interference is filtered out. By the arrangement, the safety and reliability of the control circuit of the contactor can be improved.

Fig. 2 is a schematic circuit diagram of a power module according to an embodiment of the utility model. Referring to fig. 2, the power protection unit 11 may optionally include a first varistor RV1, a first capacitor C1, a second capacitor C2, a first inductor L1, and a first common-mode inductor L2, based on the above embodiments. The rectifying and filtering unit 12 includes a first bridge rectifying circuit BR1 and a first filter capacitor C8. The voltage stabilizing filter unit 13 includes a first resistor R1, a first zener diode D2, a second filter capacitor C7, and a third capacitor C3.

The first end of the first piezoresistor RV1 is electrically connected to the first end of the power supply 2, and the second end of the first piezoresistor RV1 is electrically connected to the second end of the power supply 2. The first capacitor C1 is electrically connected in parallel to two ends of the first varistor RV 1.

The first input end of the first common mode inductor L2 is electrically connected with the second end of the first capacitor C1, the second input end of the first common mode inductor L2 is electrically connected with the first end of the first capacitor C1, the first output end of the first common mode inductor L2 is electrically connected with the second end of the second capacitor C2, and the second output end of the first common mode inductor L2 is electrically connected with the first end of the second capacitor C2.

The first end of the first inductor L1 is electrically connected to the first end of the second capacitor C2, and the second end of the first inductor L1 is used as the first output end of the power protection unit 11. The second terminal of the second capacitor C2 serves as a second output terminal of the power protection unit 11.

The first end of the first bridge rectifier circuit BR1 is electrically connected to the first end of the first filter capacitor C8, and the first end of the first filter capacitor C8 is used as the output end of the rectifier filter unit 12. The second end of the first filter capacitor C8 is electrically connected to the ground GND. The second end of the first bridge rectifier circuit BR1 is electrically connected to the first output end of the power protection unit 11, the third end of the first bridge rectifier circuit BR1 is electrically connected to the second output end of the power protection power supply, and the fourth end of the first bridge rectifier circuit BR1 is electrically connected to the ground GND.

The first end of the first resistor R1 is used as the input end of the voltage stabilizing and filtering unit 13, and the second end of the first resistor R1 is used as the output end of the voltage stabilizing and filtering unit 13. The second end of the first resistor R1 is further electrically connected to the second end of the first zener diode D2, and the first end of the first zener diode D2 is electrically connected to the ground GND. The second filter capacitor C7 is electrically connected in parallel to two ends of the first zener diode D2. The third capacitor C3 is electrically connected in parallel to two ends of the second filter capacitor C7.

The power module 1 is exemplified by the working principle that the ac voltage provided by the power supply 2 is input into the power protection unit 11, overvoltage or overcurrent protection is achieved through the first piezoresistor RV1, the first capacitor C1, the second capacitor C2, the first inductor L1 and the first common-mode inductor L2 filter out the interference of the external power network high-frequency pulse to the power module 1, and the electromagnetic interference of the control circuit module 3 itself to the outside is reduced. The first bridge rectifier circuit BR1 is connected to the ac voltage with the interference filtered, rectifies the ac voltage, and outputs a dc voltage B1 to the voltage stabilizing filter unit 13 and the contactor coil module 5 after filtering by the first filter capacitor C8. The direct current voltage enters the voltage stabilizing filter unit 13 through the first resistor R1, is stabilized through the first voltage stabilizing diode D2 and filtered by the second filter capacitor C7, and then is output to the power supply end of the control circuit module 3. Illustratively, the voltage is +12V.

In the present embodiment, the first varistor RV1, the first capacitor C1, the second capacitor C2, the first inductor L1 and the first common-mode inductor L2 are provided in the power protection unit 11, and/or the first bridge rectifier circuit BR1 and the first filter capacitor C8 are provided in the rectifier filter unit 12. And/or, a first resistor R1, a first zener diode D2, a second filter capacitor C7, and a third capacitor C3 are provided in the zener filter unit 13. The circuit is simple in structure and easy to realize, and the safety and reliability of the control circuit of the contactor can be further improved.

It should be noted that the power protection unit 11, the rectifying and filtering unit 12, and the voltage stabilizing and filtering unit 13 may be configured in other manners, which is not limited by the present utility model.

Fig. 3 is a schematic circuit diagram of a control circuit module according to an embodiment of the present utility model. Referring to fig. 3, the control circuit module 3 optionally includes a start-up unit 31, a holding unit 33, and a logic control unit 32 on the basis of the above-described embodiments.

The input terminal VCC of the starting unit 31 is used as a power supply terminal of the control circuit module 3, and the starting unit 31 is used for performing energy storage charging according to the power-up time of the voltage signal, and outputting a starting control signal 1A.

A first input of the holding unit 33 is electrically connected to a power supply of the control circuit module 3, and a second input of the holding unit 33 is electrically connected to an output of the logic control unit 32. The holding unit 33 is used for performing energy storage charging and discharging according to the input signal, and controlling the period and the duty ratio of the PWM control signal 1Y.

An output of the start-up unit 31 is electrically connected to a first input of the logic control unit 32. A first output of the holding unit 33 is electrically connected to a second input of the logic control unit 32, and a second output of the holding unit 33 is electrically connected to a third input of the logic control unit 32. The logic control unit 32 is configured to perform conversion and logic operation of logic signals according to signals at the input terminal, and output a logic control signal 2Y and a PWM control signal 1Y for controlling the holding unit 33.

Illustratively, the input terminal VCC of the starting unit 31 is connected to the voltage signal output by the power module 1, and then the starting unit 31 starts energy storage charging and outputs the starting control signal 1A to the first input terminal of the logic control unit 32. At this time, the signal at the second input terminal of the logic control unit 32 is the first initial signal, and the logic control unit 32 performs logic operation according to the signals at the first input terminal and the second input terminal, and outputs the PWM control signal 1Y. At the same time, the first input end of the holding unit 33 is connected to the voltage signal output by the power module 1, the second input end of the holding unit 33 is connected to the logic control signal 2Y output by the logic control unit 32, and the holding unit 33 starts energy storage charging and discharging. The first and second outputs of the holding unit 33 output signals to the second and third inputs of the logic control unit 32, respectively, according to the times at which the holding unit 33 is charged and discharged. The logic control unit 32 performs conversion and logic operation of logic signals according to signals of the second input terminal and the third input terminal, outputs a logic control signal 2Y to the holding unit 33, and outputs a PWM control signal 1Y to the switch executing module 4 to control the operation state of the contactor.

In this embodiment, by providing the starting unit 31, the holding unit 33, and the logic control unit 32 in the control circuit module 3, by designing the time for charging and discharging the energy stored in the starting unit 31 and the holding unit 33, the logic control unit 32 outputs a corresponding control signal, and the logic control unit 32 performs a logic operation according to each input signal and then outputs the PWM control signal 1Y with a constant duty ratio and control period. The arrangement is simple in circuit structure design, and the PWM control signal 1Y is further output by using a pure hardware circuit.

With continued reference to fig. 3, the logic control unit 32 may optionally include a comparator 323, a first nand gate 321, and a second nand gate 322 on the basis of the above embodiments.

A first input terminal of the comparator 323 is electrically connected to a first input terminal of the logic control unit 32, and a second input terminal of the comparator 323 inputs a reference voltage signal V _ref The output of the comparator 323 outputs a logic signal.

A first input of the first nand gate 321 is electrically connected to an output of the comparator 323, and a second input of the first nand gate 321 is electrically connected to a second input of the logic control unit 32. The output terminal of the first nand gate 321 outputs the PWM control signal 1Y.

The first input terminal and the second input terminal of the second nand gate 322 are electrically connected to the third input terminal of the logic control unit 32, and the output terminal of the second nand gate 322 outputs the logic control signal 2Y for controlling the holding unit 33.

Illustratively, a first input of the comparator 323 is coupled to the start-up control signal 1A output by the start-up unit 31, which the comparator 323 inputs with the reference voltage signal V input by a second input _ref And comparing to obtain a logic signal and outputting the logic signal to the first NAND gate. When the logic signal output from the comparator 323 is at a high level at the first input terminal of the first nand gate 321, and the signal output from the first output terminal of the second input terminal of the holding unit 33 is at a low level, the PWM control signal 1Y output from the output terminal of the first nand gate 321 is at a high level. The first input terminal and the second input terminal of the second nand gate 322 are both connected to the signal output from the second output terminal of the holding unit 33, and when the signal is at the low level, the logic control signal 2Y output from the output terminal of the second nand gate 322 is at the high level.

In this embodiment, by providing the first nand gate 321 and the second nand gate 322 in the logic control unit 32, logic operation on the input signal is realized, which is favorable for further realizing outputting the PWM control signal 1Y with a certain duty ratio and control period by using the logic control unit 32, so as to further control the working state of the contactor.

Fig. 4 is a circuit schematic diagram of another control circuit module according to an embodiment of the present utility model. Referring to fig. 4, the comparator 323 may optionally include a hysteresis circuit 3231, and the hysteresis circuit 3231 may be configured to hold the input signal of the nand gate.

Specifically, the hysteresis circuit 3231 is provided in the comparator 323, so that the input signal of the nand gate can be stabilized, and the signal oscillation at the output end of the nand gate caused by the continuous minute change of the signal output from the start unit 31 or the hold unit 33 can be avoided.

In this embodiment, by providing the hysteresis circuit 3231 in the comparator 323, the input signal of the nand gate can be stabilized, the output signal of the nand gate is prevented from oscillating, the generation of the PWM control signal 1Y is further facilitated, and the reliability of the control circuit is improved.

Optionally, the logic control unit 32 further includes a third nand gate and a fourth nand gate, which are electrically connected in parallel with the first nand gate 321. Specifically, the first input end of the first nand gate 321, the first input end of the third nand gate and the first input end of the fourth nand gate are electrically connected, the second input end of the first nand gate 321, the second input end of the third nand gate and the second input end of the fourth nand gate are electrically connected, and the output end of the first nand gate 321, the output end of the third nand gate and the output end of the fourth nand gate are electrically connected. The third and fourth nand gates also output the PWM control signal 1Y. In this embodiment, by setting the third nand gate and the fourth nand gate, the width of the signal transmission channel is ensured, the load capacity is improved, and the reliability of the control circuit is further improved.

Fig. 5 is a circuit schematic diagram of another control circuit module according to an embodiment of the present utility model. Referring to fig. 5, further, the first nand gate 321, the second nand gate 322, the third nand gate, and the fourth nand gate may be integrated in one nand gate chip U1 on the basis of the above embodiments. The logic control unit 32 and the nand gate chip U1 include 14 pins 1 to 14 pins, which are arranged counterclockwise. Pin 1, pin 2 and pin 3 are the first input, the second input and the output of the first nand gate 321, respectively. Pin 4, pin 5 and pin 6 are the output, first input and second input of the second nand gate 322, respectively. Pin 7 is the ground, and pins 8, 9 and 10 are the first input, the second input and the output of the third nand gate, respectively. Pin 11, pin 12 and pin 13 are the output, first input and second input of the fourth nand gate, respectively. Pin 14 is the power terminal. Pin 1, pin 8 and pin 13 all access start control signal 1A, pin 2, pin 9 and pin 12 all access signal 1B, pin 3 outputs PWM control signal 1Y, pin 4 outputs logic control signal 2Y, pin 5 and pin 6 all access signal 2A/2B, pin 7 is grounded, and pin 14 is connected with voltage signal.

In practical application, the chip integrating four NAND gates is common, has lower cost, and is beneficial to further reducing the cost on the basis of improving the reliability of the circuit.

With continued reference to fig. 5, on the basis of the above embodiments, the starting unit 31 may optionally include a second resistor R2, a fourth capacitor C4, and a third resistor R5.

The first end of the second resistor R2 is used as the input end of the starting unit 31, the second end of the second resistor R2 is used as the output end of the starting unit 31, the second end of the second resistor R2 is further electrically connected with the first end of the third resistor R5, and the second end of the third resistor R5 is grounded. The fourth capacitor C4 is connected in parallel to two ends of the third resistor R5.

Illustratively, the principle of the starting unit 31 implementing the starting control of the relay coil is that, when the power module is powered on, the voltage signal output by the power module 1 is applied to the second resistor R2 starting unit 31, and the voltage of the first ends of the fourth capacitor C4 and the third resistor R5 connected in parallel rises from 0 because the capacitor voltage cannot be suddenly changed. Before reaching the first logic threshold voltage, the signal at the second input end of the logic control unit 32 is the first initial signal, the logic control unit 32 performs conversion and logic operation of the logic signal according to the first end voltage of the third resistor R5 and the first initial signal, and outputs the PWM control signal 1Y to the switch executing module 4 to control the switch unit 41 to be turned on so as to control the contactor to be turned on.

In this embodiment, the second resistor R2, the fourth capacitor C4 and the third resistor R5 are provided in the starting unit 31, so that the fourth capacitor C4 is charged with energy, and the starting control signal 1A is output, and the contactor is controlled to start in cooperation with the logic control unit 32. The arrangement is beneficial to further realizing control on the starting of the contactor by utilizing a pure hardware circuit.

On the basis of the above embodiments, the start-up time is optionally the time when the voltage of the fourth capacitor C4 reaches the first logic threshold voltage of the logic control unit 32, since the contactor is powered up.

Specifically, the voltage of the fourth capacitor C4 is started by the contactor being powered up, and the PWM control signal 1Y output by the logic control unit 32 continuously turns on the switching unit 41 in the process of reaching the first logic threshold voltage of the logic control unit 32. When the voltage of the fourth capacitor C4 exceeds the first logic threshold voltage, the start control signal 1A output by the second end of the second resistor R2 changes, so that the PWM control signal 1Y output by the logic control unit 32 changes, and the control switch unit 41 is turned off, and the start process of the contactor is ended.

In this embodiment, by designing the voltage of the fourth capacitor C4 to be started by the contactor being powered on, the time for reaching the first logic threshold voltage of the logic control unit 32 is the start time of the contactor, so that the start time of the contactor can be accurately controlled, which is beneficial to being applied to the circuit with narrow voltage input.

Optionally, the voltage across the fourth capacitor C4 may be stabilized to a first stabilized voltage after the contactor is powered up, where the first stabilized voltage is greater than the first logic threshold voltage. The first stable voltage is related to the voltage signal, the second resistor R2, the fourth capacitor C4 and the third resistor R5.

Illustratively, the voltage across the fourth capacitor C4 is calculated as:

wherein,representing the voltage across the fourth capacitor C4, V _DD Representing the voltage signal, R ₂ Represents the resistance value of the second resistor R2, R ₅ Represents the resistance value of the third resistor R5, C ₄ The capacitance value of the fourth capacitor C4 is represented, and t represents the time of energy storage and charging of the fourth capacitor C4.

In this embodiment, by designing the voltage signal, the second resistor R2, the fourth capacitor C4 and the third resistor R5, a voltage stabilizing value at both ends of the fourth capacitor C4 can be determined, and the starting time of the contactor can be determined by dividing the voltage stabilizing value by the time for charging the fourth capacitor C4. When the voltage across the fourth capacitor C4 exceeds the first logic threshold voltage, the start control signal 1A triggers a signal change at the output of the logic control unit 32, at which point the contactor start-up process ends. Therefore, the first stable voltage needs to be greater than the first logic threshold voltage.

With continued reference to fig. 5, the holding unit 33 may optionally include a duty control subunit 331 and a period control subunit 332, on the basis of the above embodiments.

The first input of the duty cycle control subunit 331 is provided as a first input of the holding unit 33, the second input of the duty cycle control subunit 331 is provided as a second input of the holding unit 33, and the first output of the duty cycle control subunit 331 is provided as a first output of the holding unit 33. The duty ratio control subunit 331 performs energy storage charging and discharging in response to the signal of the input terminal thereof to control the duty ratio of the PWM control signal 1Y.

An input of the period control subunit 332 is electrically connected to a second output of the duty control subunit 331, and an output of the period control subunit 332 serves as a second output of the holding unit 33. The period control subunit 332 performs energy storage charging and discharging in response to the signal at the input terminal thereof to control the period of the PWM control signal 1Y.

Specifically, the first input terminal of the duty ratio control subunit 331 is connected to the voltage signal output by the power module 1, and the second input terminal is connected to the logic control signal 2Y output by the logic control unit 32. The duty cycle control subunit 331 starts energy storage charging or discharging according to the input signal of the second input terminal. Since the level of the input signal at the second input terminal is changed regularly, the first output terminal of the duty ratio control subunit 331 outputs the corresponding control signal 1B to the logic control unit 32 according to the conversion period thereof, so as to control the duty ratio of the PWM control signal 1Y. The input terminal of the period control subunit 332 is also connected to the logic control signal 2Y output by the logic control unit 32, according to which the period control subunit 332 starts energy storage charging or discharging, and the sum of the charging time and the discharging time is the period of the control PWM control signal 1Y. During the charge and discharge cycle of the period control subunit 332, the output terminal of the period control subunit 332 outputs the control signal 2A/2B of the corresponding period to the logic control unit 32.

In the present embodiment, by providing the duty control subunit 331 and the period control subunit 332 in the holding unit 33, the times at which the duty control subunit 331 and the period control subunit 332 charge and discharge are controlled, the control of the duty and the control period of the PWM control signal 1Y can be achieved. By the arrangement, accurate PWM control signals 1Y are further generated by using a pure hardware circuit, and the energy consumption of the contactor is reduced.

With continued reference to fig. 5, on the basis of the above embodiments, the duty cycle control subunit 331 optionally includes: a fourth resistor R3 and a fifth capacitor C5.

The first end of the fourth resistor R3 is used as the first input end of the duty ratio control subunit 331, the second end of the fourth resistor R3 is used as the first output end of the duty ratio control subunit 331, the second end of the fourth resistor R3 is further electrically connected to the first end of the fifth capacitor C5, and the second end of the fifth capacitor C5 is used as the second input end of the duty ratio control subunit 331.

Specifically, the voltage signal output by the power module 1 is input to the duty ratio control subunit 331 through the fourth resistor R3, and the second end of the fifth capacitor C5 is connected to the logic control signal 2Y output by the logic control unit 32. The second terminal of the fourth resistor R3 outputs a signal to the second input terminal of the logic control unit 32. For example, after the contactor is powered up, the logic control signal 2Y is at a high level, the voltage across the fifth capacitor C5 cannot be suddenly changed, and the voltage at the second end of the fourth resistor R3 is the power supply voltage. After the time of the energy storage charging of the period control subunit 332, the logic control signal 2Y is changed to a low level, and the fifth capacitor C5 starts the energy storage charging. During the process of energy storage and charging of the fifth capacitor C5, the second end voltage of the fourth resistor R3 increases from 0 to the power supply voltage and increases to twice the power supply voltage. At this time, the logic control signal 2Y input to the second terminal of the fifth capacitor C5 becomes high level, the fifth capacitor C5 starts to discharge, and after a period of time, the voltage of the second terminal of the fourth resistor R3 goes to 0. During the process of charging the fifth capacitor C5, the second terminal of the fourth resistor R3 outputs a low level signal to the second input terminal of the logic control unit 32. At this time, the first input terminal of the logic control unit 32 is at a high level, and after the logic control unit 32 performs the nand logic operation, the first output terminal outputs the PWM control signal 1Y to the switch executing module 4 to control the switch unit 41 to be turned on, so as to control the contactor to be turned on.

In the present embodiment, by providing the fourth resistor R3 and the fifth capacitor C5, the fifth capacitor C5 performs cyclic energy storage charging and discharging according to the voltage signal and the logic control signal 2Y, so as to control the duty ratio of the PWM control signal 1Y. The arrangement is beneficial to further realizing the generation of an accurate PWM control signal 1Y by using a pure hardware circuit and reducing the energy consumption of the contactor.

On the basis of the above embodiments, optionally, the duty ratio of the PWM control signal 1Y is a ratio of a time when the voltage of the fifth capacitor C5 is charged from the initial capacitance value to the first logic threshold voltage to the period of the PWM control signal 1Y.

Specifically, during the operation of the holding unit 33, the PWM control signal 1Y controls the switching unit 41 to be turned on only during the period in which the voltage of the fifth capacitor C5 is charged from the initial capacitance value to the first logic threshold voltage.

In this embodiment, the duty ratio of the PWM control signal 1Y is determined by designing the time when the voltage of the fifth capacitor C5 is charged from the initial capacitance value to the first logic threshold voltage, which is favorable for further realizing the generation of the accurate PWM control signal 1Y by using a pure hardware circuit and reducing the energy consumption of the contactor.

On the basis of the above embodiments, optionally, the voltage of the fifth capacitor C5 is charged from the initial capacitance value to the first logic threshold voltage for a time T ₁ Is associated with the voltage signal, the fourth resistor R3, the fifth capacitor C5, and the first logic threshold voltage.

Illustratively, the voltage of the fifth capacitor C5 is charged from the initial capacitance value to the first logic threshold voltage for a time T ₁ The calculation formula of (2) is as follows:

wherein R is ₃ Represents the resistance value of the fourth resistor R3, C ₅ Representing the capacitance value of the fifth capacitor C5, V _P Representing a first logic threshold voltage.

Duty ratio T of PWM control signal 1Y _d The calculation formula of (2) is as follows:

where T represents the period of the PWM control signal 1Y.

In this embodiment, by designing the voltage signal, the fourth resistor R3, the fifth capacitor C5, and the first logic threshold voltage, the duty ratio of the PWM control signal 1Y may be determined, which is favorable for further realizing the generation of the accurate PWM control signal 1Y by using a pure hardware circuit and reducing the energy consumption of the contactor.

With continued reference to fig. 5, on the basis of the above embodiments, the cycle control subunit 332 optionally includes: a fifth resistor R6 and a sixth capacitor C6.

The first end of the fifth resistor R6 is used as the input end of the period control subunit 332, the second end of the fifth resistor R6 is used as the output end of the period control subunit 332, the second end of the fifth resistor R6 is further electrically connected to the first end of the sixth capacitor C6, and the second end of the sixth capacitor C6 is grounded.

Specifically, the first end of the fifth resistor R6 is connected to the logic control signal 2Y output from the logic control unit 32. The second terminal of the fifth resistor R6 outputs a signal to the third input terminal of the logic control unit 32. For example, after the contactor is powered up, the logic control signal 2Y is at a high level, and at this time, the second terminal voltage of the fifth resistor R6 is 0, and the sixth capacitor C6 starts to store energy for charging. During the process of energy storage charging of the sixth capacitor C6, the second terminal voltage of the fifth resistor R6 rises from 0 to the first logic threshold voltage. At this time, the input logic control signal 2Y becomes low level, the sixth capacitor C6 starts to discharge, and after a period of time, the second terminal voltage of the fifth resistor R6 reaches the second logic threshold voltage. During the process of charging and discharging the sixth capacitor C6, the second end of the fifth resistor R6 outputs a signal to the logic control unit 32, and the logic control unit 32 continuously outputs the PWM control signal 1Y.

In the present embodiment, the fifth resistor R6 and the sixth capacitor C6 are provided, so that the sixth capacitor C6 performs cyclic energy storage charging and discharging according to the logic control signal 2Y to control the control period of the PWM control signal 1Y. The arrangement is beneficial to further realizing the generation of an accurate PWM control signal 1Y by using a pure hardware circuit and reducing the energy consumption of the contactor.

On the basis of the above embodiments, optionally, the period of the PWM control signal 1Y is the sum of the time when the voltage of the sixth capacitor C6 is charged from the initial capacitance value to the first logic threshold voltage and the time when the voltage of the sixth capacitor C6 is discharged from the first logic threshold voltage to the second logic threshold voltage of the logic control unit 32.

Specifically, the logic control unit 32 outputs the PWM control signal 1Y during both the process of charging the voltage of the sixth capacitor C6 from the initial capacitance value to the first logic threshold voltage and the process of discharging the voltage of the sixth capacitor C6 from the first logic threshold voltage to the second logic threshold voltage of the logic control unit 32.

In this embodiment, the control period of the PWM control signal 1Y is determined by designing the time when the voltage of the sixth capacitor C6 is charged from the initial capacitance value to the first logic threshold voltage and the time when the voltage of the sixth capacitor C6 is discharged from the first logic threshold voltage to the second logic threshold voltage of the logic control unit 32, which is favorable for further realizing the generation of the accurate PWM control signal 1Y by using a pure hardware circuit and reducing the energy consumption of the contactor.

Based on the above embodiments, optionally, the voltage of the sixth capacitor C6 is charged from the initial capacitance value to the first logic threshold voltage for a time T _c Is associated with the voltage signal, the fifth resistor R6, the sixth capacitor C6, the first logic threshold voltage, and the second logic threshold voltage. The time T when the voltage of the sixth capacitor C6 is discharged from the first logic threshold voltage to the second logic threshold voltage of the logic control unit 32 _f Is associated with a fifth resistor R6, a sixth capacitor C6, a first logic threshold voltage, and a second logic threshold voltage.

Illustratively, the voltage of the sixth capacitor C6 is charged from the initial capacitance value to the first logic threshold voltage for a time T _c The calculation formula of (2) is as follows:

wherein R is ₆ Represents the resistance value of the fifth resistor R6, C ₆ Representing the capacitance value of the sixth capacitor C6, V _N Representing a second logic threshold voltage.

The time T when the voltage of the sixth capacitor C6 is discharged from the first logic threshold voltage to the second logic threshold voltage of the logic control unit 32 _f The calculation formula of (2) is as follows:

the calculation formula of the period T of the PWM control signal 1Y is:

in this embodiment, the control period of the PWM control signal 1Y may be determined by designing the fifth resistor R6, the sixth capacitor C6, the first logic threshold voltage and the second logic threshold voltage, which is favorable for further realizing the generation of the accurate PWM control signal 1Y by using a pure hardware circuit and reducing the energy consumption of the contactor.

With continued reference to fig. 5, the holding unit 33 may further include a seventh capacitor C9 and an eighth capacitor C12, as an option, on the basis of the above-described embodiments. The seventh capacitor C9 and the eighth capacitor C12 are respectively used for performing energy storage charging and discharging when the fifth capacitor C5 and the sixth capacitor C6 fail.

Fig. 6 is a schematic circuit diagram of a connection between a switch executing module and a contactor coil module according to an embodiment of the present utility model. Referring to fig. 6, the switch executing module 4 may further include a sixth resistor R4 and a seventh resistor R7, as an option, based on the above embodiments. The switching unit 41 includes a first switching tube Q1. The contactor coil module 5 further includes a fast recovery diode D1.

The first switching tube Q1 and the electromagnetic coil 51 are electrically connected in series.

The first end of the sixth resistor R4 is used as the input end of the switch executing module 4, and the second end of the sixth resistor R4, the first end of the seventh resistor R7 and the control end of the first switch tube Q1 are electrically connected. The second terminal of the seventh resistor R7 and the second terminal of the first switching tube Q1 are electrically connected to the ground GND.

The fast recovery diode D1 is electrically connected in anti-parallel with the electromagnetic coil 51.

Specifically, the PWM control signal 1Y is input to the control terminal of the first switching tube Q1 through the sixth resistor R4, and controls the first switching tube Q1 to be turned on or off. When the first switching tube Q1 is conducted, the electromagnetic coil 51 connected in series with the first switching tube Q1 is powered on, and the contactor is controlled to be closed; when the first switching tube Q1 is turned off, the electromagnetic coil 51 connected in series with the first switching tube Q1 is deenergized, and at this time, the loop control contactor formed by the electromagnetic coil 51 and the fast recovery diode D1 is kept closed.

In this embodiment, by providing the fast recovery diode D1, the first switching tube Q1, the sixth resistor R4, and the seventh resistor R7, direct control of the contactor coil according to the PWM control signal 1Y is achieved, and instantaneity of contactor control is further improved.

Fig. 7 is a flowchart of a method executed by a control circuit of a contactor according to an embodiment of the present utility model, referring to fig. 7, the method may include the following steps:

s110, performing voltage conversion on the power supply voltage based on the power supply module.

Specifically, the power module rectifies and filters the supply voltage.

And S120, carrying out logic operation and energy storage charge and discharge on the input voltage signal based on the control circuit module, and outputting a PWM control signal.

Specifically, the control circuit module performs energy storage charging and discharging on the voltage signal, performs logic operation, and outputs a PWM control signal with a certain duty ratio and control period.

And S130, on-off is performed based on the response of the switch execution module to the PWM control signal, so that the contactor is controlled to be closed or opened.

Specifically, the on state of the switch execution module is controlled according to the PWM control signal, so that the working state of the contactor is controlled, and the energy consumption of the contactor can be reduced.

In the embodiment, the control circuit module performs energy storage charging and discharging on the voltage signal output by the power supply module, controls the charging and discharging time through logic operation, and outputs a PWM control signal with a certain duty ratio and a certain control period. And controlling the conducting state of the switch execution module by using the PWM control signal, thereby controlling the working state of the contactor. Compared with the prior art, the technical scheme of the embodiment reduces signal delay and improves the real-time performance of contactor control.

It should be appreciated that various forms of the flows shown above may be used to reorder, add, or delete steps. For example, the steps described in the present utility model may be performed in parallel, sequentially, or in a different order, so long as the desired results of the technical solution of the present utility model are achieved, and the present utility model is not limited herein.

The above embodiments do not limit the scope of the present utility model. It will be apparent to those skilled in the art that various modifications, combinations, sub-combinations and alternatives are possible, depending on design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included in the scope of the present utility model.

Claims (12)

1. A control circuit for a contactor, comprising:

the input end of the power supply module is electrically connected with a power supply, and the power supply module is used for carrying out voltage conversion on the power supply voltage;

the switch executing module comprises a switch unit, and the electromagnetic coil and the switch unit are connected in series between the output end of the power supply module and the grounding end;

the power supply end of the control circuit module is electrically connected with the power supply module, and the output end of the control circuit module is electrically connected with the control end of the switch execution module; the control circuit module is used for carrying out energy storage charge and discharge, conversion of logic signals and logic operation on input voltage signals and outputting PWM control signals so as to control on or off of the switch unit and control on or off of the contactor.

2. The circuit of claim 1, wherein the power module comprises: the device comprises a power supply protection unit, a rectifying and filtering unit and a voltage stabilizing and filtering unit;

the input end of the power supply protection unit is used as the input end of the power supply module, and the output end of the power supply protection unit is connected with the input end of the rectifying and filtering unit; the power supply protection unit is used for protecting the power supply module and filtering electromagnetic interference;

The output end of the rectifying and filtering unit is electrically connected with the input end of the voltage stabilizing and filtering unit, and the output end of the rectifying and filtering unit is electrically connected with the contactor coil module; the rectification filter unit is used for converting alternating current into direct current and supplying power for the voltage stabilizing filter unit and the contactor coil module;

the output end of the voltage stabilizing filter unit is electrically connected with the control circuit module; the voltage stabilizing and filtering unit is used for stabilizing and filtering the input direct current and supplying power to the control circuit module.

3. The circuit of claim 2, wherein the power protection unit comprises a first varistor, a first capacitor, a second capacitor, a first inductor, and a first common-mode inductor; and/or the rectifying and filtering unit comprises a first bridge rectifying circuit and a first filtering capacitor; and/or the voltage stabilizing and filtering unit comprises a first resistor, a first voltage stabilizing diode, a second filtering capacitor and a third capacitor;

the first end of the first piezoresistor is electrically connected with the first end of the power supply, and the second end of the first piezoresistor is electrically connected with the second end of the power supply; the first capacitor is electrically connected to two ends of the first piezoresistor in parallel;

The first input end of the first common mode inductor is electrically connected with the second end of the first capacitor, the second input end of the first common mode inductor is electrically connected with the first end of the first capacitor, the first output end of the first common mode inductor is electrically connected with the second end of the second capacitor, and the second output end of the first common mode inductor is electrically connected with the first end of the second capacitor;

the first end of the first inductor is electrically connected with the first end of the second capacitor, and the second end of the first inductor is used as a first output end of the power supply protection unit; the second end of the second capacitor is used as a second output end of the power supply protection unit;

the first end of the first bridge rectifier circuit is electrically connected with the first end of the first filter capacitor, and the first end of the first filter capacitor is used as the output end of the rectifier filter unit; the second end of the first filter capacitor is electrically connected with the grounding end; the second end of the first bridge rectifier circuit is electrically connected with the first output end of the power supply protection unit, the third end of the first bridge rectifier circuit is electrically connected with the second output end of the power supply protection power supply, and the fourth end of the first bridge rectifier circuit is electrically connected with the grounding end;

The first end of the first resistor is used as the input end of the voltage stabilizing and filtering unit, and the second end of the first resistor is used as the output end of the voltage stabilizing and filtering unit; the second end of the first resistor is also electrically connected with the second end of the first zener diode, and the first end of the first zener diode is electrically connected with the grounding end; the second filter capacitor is electrically connected in parallel with two ends of the first zener diode; the third capacitor is electrically connected in parallel with two ends of the second filter capacitor.

4. The circuit of claim 1, wherein the control circuit module comprises a start-up unit, a hold unit, and a logic control unit;

the input end of the starting unit is used as a power supply end of the control circuit module, and the starting unit is used for carrying out energy storage and charging according to the power-on time of the voltage signal and outputting a starting control signal;

the first input end of the holding unit is electrically connected with the power supply end of the control circuit module, and the second input end of the holding unit is electrically connected with the output end of the logic control unit; the holding unit is used for carrying out energy storage charging and discharging according to the input signals and controlling the period and the duty ratio of the PWM control signals;

The output end of the starting unit is electrically connected with the first input end of the logic control unit; the first output end of the holding unit is electrically connected with the second input end of the logic control unit, and the second output end of the holding unit is electrically connected with the third input end of the logic control unit; the logic control unit is used for performing conversion and logic operation of logic signals according to signals of the input end and outputting logic control signals and PWM control signals for controlling the holding unit.

5. The circuit of claim 4, wherein the start-up unit comprises a second resistor, a fourth capacitor, and a third resistor;

the first end of the second resistor is used as an input end of the starting unit, the second end of the second resistor is used as an output end of the starting unit, the second end of the second resistor is also electrically connected with the first end of the third resistor, and the second end of the third resistor is grounded; the fourth capacitor is connected in parallel with two ends of the third resistor.

6. The circuit of claim 4, wherein the holding unit comprises a duty cycle control subunit and a period control subunit;

The first input end of the duty ratio control subunit is used as the first input end of the holding unit, the second input end of the duty ratio control subunit is used as the second input end of the holding unit, and the first output end of the duty ratio control subunit is used as the first output end of the holding unit; the duty ratio control subunit responds to the signal of the input end of the duty ratio control subunit to perform energy storage charge and discharge so as to control the duty ratio of the PWM control signal;

the input end of the period control subunit is electrically connected with the second output end of the duty ratio control subunit, and the output end of the period control subunit is used as the second output end of the holding unit; and the period control subunit responds to the signal of the input end of the period control subunit to perform energy storage charge and discharge so as to control the period of the PWM control signal.

7. The circuit of claim 6, wherein the duty cycle control subunit comprises: a fourth resistor and a fifth capacitor;

the first end of the fourth resistor is used as the first input end of the duty ratio control subunit, the second end of the fourth resistor is used as the first output end of the duty ratio control subunit, the second end of the fourth resistor is also electrically connected with the first end of the fifth capacitor, and the second end of the fifth capacitor is used as the second input end of the duty ratio control subunit.

8. The circuit of claim 6, wherein the period control subunit comprises: a fifth resistor and a sixth capacitor;

the first end of the fifth resistor is used as the input end of the period control subunit, the second end of the fifth resistor is used as the output end of the period control subunit, the second end of the fifth resistor is also electrically connected with the first end of the sixth capacitor, and the second end of the sixth capacitor is grounded.

9. The circuit of claim 4, wherein the logic control unit comprises a comparator, a first nand gate, and a second nand gate;

the first input end of the comparator is electrically connected with the first input end of the logic control unit, the second input end of the comparator inputs a reference voltage signal, and the output end of the comparator outputs a logic signal;

a first input end of the first NAND gate is electrically connected with an output end of the comparator, and a second input end of the first NAND gate is electrically connected with a second input end of the logic control unit; the output end of the first NAND gate outputs the PWM control signal;

the first input end and the second input end of the second NAND gate are electrically connected with the third input end of the logic control unit, and the output end of the second NAND gate outputs a logic control signal for controlling the holding unit.

10. The circuit of claim 9, wherein the comparator comprises a hysteresis circuit for holding the input signal of the nand gate.

11. The circuit of claim 9, wherein the logic control unit further comprises a third nand gate and a fourth nand gate, each of the third nand gate and the fourth nand gate being electrically connected in parallel with the first nand gate.

12. The circuit of claim 1, wherein the switch execution module further comprises a sixth resistor and a seventh resistor; the switch unit comprises a first switch tube; the contactor coil module further comprises a fast recovery diode;

the first switch tube and the electromagnetic coil are electrically connected in series;

the first end of the sixth resistor is used as an input end of the switch execution module, and the second end of the sixth resistor, the first end of the seventh resistor and the control end of the first switch tube are electrically connected; the second end of the seventh resistor and the second end of the first switch tube are electrically connected with a grounding end;

the fast recovery diode is electrically connected in anti-parallel with the electromagnetic coil.