Anti-burning relay coil control circuit

Abstract

The utility model provides an anti-burnout relay coil control circuit, which comprises a relay control module and an IGBT module, the relay control module is connected with an external controller, the IGBT module and the relay control module are connected in series to a high-voltage circuit, and the other end of the IGBT module is connected with a load; an external controller is used for controlling high-low level inversion of an outlet signal and a control signal of the relay control module so as to control the IGBT module to serve as a secondary switch to control on-off of the relay, and then the motor is controlled to act. The anti-burning relay coil control circuit can greatly reduce the reverse electromotive force of the motor, thereby avoiding the phenomenon of high-voltage arc discharge or relay sparking, further protecting the relay, and preventing the relay from being burnt.

Description

Technical Field

[0001] The utility model belongs to the technical field of relay protection, in particular to a relay coil control circuit that prevents burning. Background Art

[0002] A common problem with current DC circuit breaker operating boxes is the burning of relay coils. This problem is mainly caused by the fact that relays generally control motors, generators and other equipment, most of which have inductive characteristics. When the power is suddenly cut off, the current at both ends of the inductor cannot change suddenly, so a certain reverse current will appear, resulting in high-voltage arcs or sparks. If the time is too long, the coil will inevitably heat up severely and eventually burn out. Utility Model Content

[0003] In view of this, the present invention aims to provide a relay coil control circuit for preventing burnout, so as to solve the problem of relay coil heating and burning.

[0004] In order to achieve the above-mentioned purpose, the technical solution of the utility model is achieved as follows:

[0005] The utility model provides an anti-burn relay coil control circuit, comprising a relay control module and an IGBT module, wherein the relay control module is connected to an external controller, the IGBT module and the relay control module are connected in series to a high-voltage circuit, and the other end of the IGBT module is connected to a load;

[0006] The output signal of the relay control module and the high and low level inversion of the control signal are controlled by an external controller to control the IGBT module as a secondary switch to control the on and off of the relay, thereby controlling the action of the motor.

[0007] Furthermore, the IGBT module includes an IGBT voltage drive module, an IGBT control module and a signal inversion drive control module connected to each other;

[0008] The IGBT voltage driving module is configured to provide switching and shutoff voltages to the IGBT;

[0009] The IGBT control module is configured to control the on and off of the IGBT;

[0010] The signal inversion drive control module is configured to provide level conversion of the output signal and the control signal.

[0011] Further, the relay control module includes a relay unit, and the IGBT voltage driving module includes a first main control unit;

[0012] The IGBT control module includes a second main control unit, a fifth pin of the second main control unit is connected to the seventh pin of the first main control unit, and an eighth pin of the second main control unit is connected to the fifth pin of the first main control unit through a first resistor and to the sixth pin of the first main control unit through a second resistor;

[0013] The sixth pin of the second main control unit is connected to the first end of the IGBT through a third resistor, a varistor is connected in parallel between the second and third ends of the IGBT, an end of the third resistor away from the second main control unit is connected to the third end of the IGBT through a first switching tube and a fourth resistor connected in parallel, the seventh pin of the second main control unit is connected to the line between the third resistor and the first switching tube through a fifth resistor, one end of the varistor is connected to the fourteenth and twenty-fourth pins of the relay unit, and the other end is connected to the eleventh and twenty-first pins of the relay unit through a first adapter terminal;

[0014] The second pin and the third pin of the second main control unit are both connected to the signal inversion drive control module, and the signal inversion drive control module is connected to an external controller.

[0015] Furthermore, two ends of the third resistor are connected in parallel with a second switch tube;

[0016] The first switch tube is a bidirectional breakdown diode, and the second switch tube is a voltage regulator diode.

[0017] Furthermore, the signal inversion drive control module includes a first inversion circuit for level conversion of the output signal;

[0018] The first inversion circuit includes a third main control unit, the third pin of the third main control unit is connected to the A1 pin of the relay unit through a sixth resistor, and the third pin and the fifth pin of the third main control unit are connected to the A1 pin of the relay unit through a seventh resistor;

[0019] The fourth pin of the third main control unit is connected to the third pin of the second main control unit through an eighth resistor and a ninth resistor;

[0020] The first pin of the third main control unit is connected to the external controller through the second adapter terminal.

[0021] Furthermore, the signal inversion drive control module includes a second inversion circuit for level conversion of the control signal;

[0022] The second inversion circuit includes a fourth main control unit, the second pin of the fourth main control unit is connected to the second pin of the second main control unit, the first pin of the fourth main control unit is connected to the external controller through a second adapter terminal, and the first pin of the fourth main control unit is also grounded through a first capacitor.

[0023] Furthermore, it also includes a power supply module, which is configured to supply power to the IGBT voltage driving module, the IGBT control module and the signal inversion driving control module.

[0024] Compared with the prior art, the anti-burn relay coil control circuit described in the present invention has the following beneficial effects:

[0025] The anti-burn relay coil control circuit described in the utility model can greatly reduce the reverse electromotive force of the motor, thereby avoiding the phenomenon of high-voltage arcing or relay sparking, thereby further protecting the relay and preventing the relay from being burned. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings, which constitute part of the present invention, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0027] Figure 1 This is a schematic diagram of a burn-out prevention relay coil control circuit according to an embodiment of the present utility model;

[0028] Figure 2 This is a circuit diagram of the relay control module according to an embodiment of the present utility model;

[0029] Figure 3 This is a circuit diagram of the IGBT voltage drive module according to an embodiment of the present utility model;

[0030] Figure 4 This is a circuit diagram of the IGBT control module according to an embodiment of the present utility model;

[0031] Figure 5 This is a circuit diagram of the signal inversion drive control module according to an embodiment of the present utility model;

[0032] Figure 6 This is a circuit diagram of the second transfer terminal according to an embodiment of the present utility model;

[0033] Figure 7 This is a circuit diagram of the power module described in an embodiment of the present utility model. DETAILED DESCRIPTION

[0034] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features therein can be combined with each other.

[0035] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0036] See also Figures 1 to 6 As shown, this embodiment provides an anti-burn relay coil control circuit, including a relay control module and an IGBT module, the relay control module is connected to an external controller, the IGBT module and the relay control module are connected in series to a high-voltage circuit, and the other end of the IGBT module is connected to a load;

[0037] The output signal of the relay control module and the high and low level reversal of the control signal are controlled by an external controller to control the on and off of the relay by the IGBT module as a secondary switch, thereby controlling the motor operation.

[0038] Specifically, in this embodiment, in order to overcome the problem of relay coil burning, the design scheme of the present application uses an IGBT module as a secondary switch, which is connected in series with the relay switch to the high-voltage circuit to control the operation of the motor.

[0039] As a circuit breaker operating box, since the reverse electromotive force of the motor can reach thousands of volts or even higher, after adding the IGBT module, when the IGBT module is disconnected, the reverse electromotive force applied to both ends of the relay is measured to be about 600V, which greatly reduces the reverse electromotive force of the motor, thereby avoiding high-voltage arcing or relay sparking, thereby further protecting the relay and preventing the relay from burning.

[0040] In some embodiments, as Figures 3 to 5 As shown, the IGBT module includes an IGBT voltage drive module, an IGBT control module and a signal inversion drive control module connected to each other;

[0041] The IGBT voltage driver module is configured to provide switching and shutoff voltages to the IGBT;

[0042] The IGBT control module is configured to control the on and off of the IGBT;

[0043] The signal inversion drive control module is configured to provide level conversion of the output signal and the control signal

[0044] Specifically, in this embodiment, the solution includes an IGBT voltage drive module, an IGBT control module, a signal inversion drive control module and a relay control module. The IGBT control module is mainly used to control the IGBT as a secondary switch to turn on and off, and the relay unit is used as a primary switch to control the motor as a whole to perform related actions.

[0045] In some embodiments, the relay control module includes a relay unit K1, and the IGBT voltage driving module includes a first main control unit;

[0046] The IGBT control module includes a second main control unit, a fifth pin of the second main control unit is connected to the seventh pin of the first main control unit, and an eighth pin of the second main control unit is connected to the fifth pin of the first main control unit through a first resistor and to the sixth pin of the first main control unit through a second resistor;

[0047] The sixth pin of the second main control unit is connected to the first end of the IGBT via a third resistor. A second switching tube (the second switching tube used in this embodiment is a voltage-stabilizing diode) is further connected in parallel at both ends of the third resistor. A varistor is connected in parallel between the second and third ends of the IGBT. The end of the third resistor away from the second main control unit is connected to the third end of the IGBT via a first switching tube (the first switching tube used in this embodiment is a bidirectional breakdown diode) and a fourth resistor connected in parallel. The seventh pin of the second main control unit is connected to the line between the third resistor and the first switching tube via a fifth resistor. One end of the varistor is connected to the fourteenth and twenty-fourth pins of the relay unit K1, and the other end is connected to the eleventh and twenty-first pins of the relay unit K1 via a first adapter terminal XS3.

[0048] The second pin and the third pin of the second main control unit are both connected to the signal inversion drive control module, and the signal inversion drive control module is connected to the external controller.

[0049] Specifically, in this embodiment, Figure 3 As shown, the IGBT voltage drive module provides turn-on and turn-off voltages for the IGBT. The VIN pin of the chip U3 is connected to the input voltage of the DC voltage PWR_DO. At the same time, a 10uf capacitor is connected between the VIN pin and the GND pin. The +VO pin of the chip U3 provides the forward conduction voltage +15V-IGBT for the IGBT. The -VO pin of the chip U3 provides the turn-off voltage -8V-IGBT for the IGBT. One end of the 0V pin of the chip U3 is connected to the capacitor C3, one end is connected to the +VO pin of the chip U3, and one end is connected to the -VO pin of the chip U3.

[0050] like Figure 4As shown, the IGBT control module mainly controls the on and off of the IGBT. The VCC1 pin input of the chip U6 is the DC voltage PWR_DO, the GND pin of the chip U6 is connected to GND, the IN+ pin of the chip U6 is connected to the reverse signal DO33 / of the output DO33, the IN- pin is connected to one end of the resistor R14, R14 is connected to the reverse signal BS / of the BS control signal, the VCC2 of the chip U6 is connected to the output pin +VO of the chip U3, the VEE2 pin is connected to the -VO pin of the chip U3, and at the same time, capacitors C18 and C19 are connected between the VCC2 and VEE2 of the chip U6 respectively, the OUT pin of the chip U6 is connected to the resistor R9, the resistor R9 is connected in parallel with the voltage regulator D3, the CLAMP pin of the chip U6 is connected to the resistor R9, the resistor R18 is connected between the G and E pins of the IGBT chip Q3, and the varistor RV3 is connected between the CE of the IGBT chip Q3.

[0051] like Figure 2 As shown, the relay control module: the A1 pin of the relay unit K1 is connected to the BS control signal, the A2 pin is connected to the output signal DO14, the diode V1 is connected between A1 and A2, the 11 pin of the relay K1 is connected to the terminal X01, and the 14 pin is connected to the C terminal of the IGBT1+.

[0052] The A pin of chip U13 is connected to the external control signal DOSTART1, one end of the external control signal is connected to resistor R71, and the other end of resistor R71 is connected to PWR_DO. The A / pin of chip U13 is connected to the signal DOSTART2, one end of the DOSTART2 signal is connected to resistor R49, resistor R49 is connected to the G pole of the MOS tube, and both ends of the GS pole of the MOS tube are connected to resistor R43. One end of the D pole of the MOS tube is connected to diode V15 and also connected to resistor R53. Resistor R53 and diode V15 are connected in parallel, and the other end is connected to GND.

[0053] In this embodiment, an IGBT is added and used as a secondary switch in series with the relay switch. The IGBT is connected in parallel with the thermistor, which plays a role of voltage clamping and shortens the closing time of the relay switch. By connecting the voltage clamping unit (varistor) in parallel with the IGBT, when there is a large reverse current in the system, the IGBT is first disconnected, so that the reverse electromotive force passes through the voltage clamping unit (referring to the varistor), clamping the high voltage of about 1KV to 600V. The voltage is clamped within a certain range by the varistor, thereby reducing the phenomenon of high-voltage arcing or sparking caused by the breakdown of the relay switch, thereby further preventing the relay from burning out.

[0054] It should be noted that this embodiment is explained based on a circuit part consisting of a relay unit, an IGBT voltage drive module, and an IGBT control module. In addition, several circuits can be set to achieve on-off control of multiple motors. There is no specific limit on the number here.

[0055] In some embodiments, as Figure 5 As shown, the signal inversion drive control module includes a first inversion circuit for converting the level of the output signal;

[0056] The first inversion circuit includes a third main control unit, the third pin of the third main control unit is connected to the A1 pin of the relay unit through a sixth resistor, and the third pin and the fifth pin of the third main control unit are connected to the A1 pin of the relay unit through a seventh resistor;

[0057] The fourth pin of the third main control unit is connected to the third pin of the second main control unit through the eighth resistor and the ninth resistor;

[0058] The first pin of the third main control unit is connected to the external controller through the second adapter terminal.

[0059] The signal inversion drive control module includes a second inversion circuit for converting the level of the control signal;

[0060] The second inversion circuit includes a fourth main control unit, the second pin of the fourth main control unit is connected to the second pin of the second main control unit, and the first pin of the fourth main control unit is connected to the second main control unit through a second adapter terminal (the second adapter terminal is as shown in FIG. Figure 6 As shown) is connected to the external controller, and the first pin of the fourth main control unit is also grounded through the first capacitor.

[0061] Specifically, in this embodiment, the signal inversion drive control module includes a first inversion circuit and a second inversion circuit. The two circuits have the same function of inverting the signal level. This embodiment uses the second inversion circuit inverting the control signal DO33 as an example for explanation.

[0062] The A pin of chip U14 is connected to the DO33 output signal, the A / pin of chip U14 is connected to the inverse signal of DO33, the DO33 / signal. The B pin of chip U14 is connected to the DO17 output signal, the B / pin is connected to the inverse signal of DO17, the DO17 / signal. The C pin of the chip is connected to the DO37 output signal, the C / pin of the chip is connected to the inverse signal of DO37, the DO37 / signal. The VSS pin of chip U14 is connected to GND. The D pin of chip U14 is connected to the DO36 output signal, the D / pin of chip U14 is connected to the inverse signal of DO36, the DO33 / signal. The E pin of chip U14 is connected to the DO17 output signal, the E / pin is connected to the inverse signal of DO40, the DO40 / signal. The F pin of the chip is connected to the DO36 output signal, the F / pin of the chip is connected to the inverse signal of DO37, the DO36 / signal. The VDD pin of chip U14 is connected to PWR_DO.

[0063] In some embodiments, as Figure 7 As shown, it also includes a power supply module, which is configured to supply power to the IGBT voltage drive module, the IGBT control module and the signal inversion drive control module, and the PWR_DO terminal is connected to a DC power supply to provide a 5V voltage source.

[0064] The working principle of the control circuit described in this embodiment is as follows:

[0065] The IGBT chip, acting as a secondary switch, primarily controls the relay's opening and closing by inverting the high and low levels of related output signals and control signals through an external controller. When the motor needs to be powered on, DO33 is first inverted via the signal inversion drive control module U14, generating signal DO33 / . The BS signal is then inverted via the signal inversion drive control module U13, generating BS / . Control of the BS and DO33 signals achieves the desired IGBT on / off state.

[0066] When the motor is to be turned on, the BS signal first controls the relay to be in the on state as the primary switch closure, and then the controller controls the DO33 / signal to make it high level, and the IGBTs as the secondary switches are turned on successively, and the motor obtains a complete closed circuit and is turned on.

[0067] When the motor circuit control is disconnected, the control end first controls the DO33 / signal to a low level through the signal inversion module, and the IGBT is disconnected first. In this way, the reverse electromotive force generated by the motor will be clamped to about 600V through the varistor RV3, and then the control end controls the BS signal to disconnect the relay again. Due to the clamping function of the varistor, the voltage value of the reverse electromotive force on the relay end is smaller, so that it can achieve the effect of rapid closing, reducing the closing time and further avoiding the phenomenon of sparking and burning of the relay.

[0068] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and description of the present invention.

[0069] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A burn-out prevention relay coil control circuit, characterized in that: It includes a relay control module and an IGBT module, wherein the relay control module is connected to an external controller, the IGBT module and the relay control module are connected in series to a high-voltage circuit, and the other end of the IGBT module is connected to a load; The output signal of the relay control module and the high and low level inversion of the control signal are controlled by an external controller to control the IGBT module as a secondary switch to control the on and off of the relay, thereby controlling the action of the motor.

2. The anti-burn relay coil control circuit according to claim 1, characterized in that: The IGBT module includes an IGBT voltage drive module, an IGBT control module and a signal inversion drive control module connected to each other; The IGBT voltage driving module is configured to provide switching and shutoff voltages to the IGBT; The IGBT control module is configured to control the on and off of the IGBT; The signal inversion drive control module is configured to provide level conversion of the output signal and the control signal.

3. The anti-burn relay coil control circuit according to claim 2, characterized in that: The relay control module includes a relay unit, and the IGBT voltage driving module includes a first main control unit; The IGBT control module includes a second main control unit, a fifth pin of the second main control unit is connected to the seventh pin of the first main control unit, and an eighth pin of the second main control unit is connected to the fifth pin of the first main control unit through a first resistor and to the sixth pin of the first main control unit through a second resistor; The sixth pin of the second main control unit is connected to the first end of the IGBT through a third resistor, a varistor is connected in parallel between the second and third ends of the IGBT, an end of the third resistor away from the second main control unit is connected to the third end of the IGBT through a first switching tube and a fourth resistor connected in parallel, the seventh pin of the second main control unit is connected to the line between the third resistor and the first switching tube through a fifth resistor, one end of the varistor is connected to the fourteenth and twenty-fourth pins of the relay unit, and the other end is connected to the eleventh and twenty-first pins of the relay unit through a first adapter terminal; The second pin and the third pin of the second main control unit are both connected to the signal inversion drive control module, and the signal inversion drive control module is connected to an external controller.

4. The anti-burn relay coil control circuit according to claim 3, characterized in that: The two ends of the third resistor are further connected in parallel with a second switch tube; The first switch tube is a bidirectional breakdown diode, and the second switch tube is a voltage regulator diode.

5. The anti-burn relay coil control circuit according to claim 3, characterized in that: The signal inversion drive control module includes a first inversion circuit for converting the level of the output signal; The first inversion circuit includes a third main control unit, the third pin of the third main control unit is connected to the A1 pin of the relay unit through a sixth resistor, and the third pin and the fifth pin of the third main control unit are connected to the A1 pin of the relay unit through a seventh resistor; The fourth pin of the third main control unit is connected to the third pin of the second main control unit through an eighth resistor and a ninth resistor; The first pin of the third main control unit is connected to the external controller through the second adapter terminal.

6. The burn-out prevention relay coil control circuit according to claim 3, characterized in that: The signal inversion drive control module includes a second inversion circuit for converting the level of the control signal; The second inversion circuit includes a fourth main control unit, the second pin of the fourth main control unit is connected to the second pin of the second main control unit, the first pin of the fourth main control unit is connected to the external controller through a second adapter terminal, and the first pin of the fourth main control unit is also grounded through a first capacitor.

7. The anti-burn relay coil control circuit according to claim 2, characterized in that: It also includes a power supply module, which is configured to supply power to the IGBT voltage driving module, the IGBT control module and the signal inversion driving control module.

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