A control circuit for dual power three-phase power switching control

Abstract

The present invention discloses a control circuit for dual-power three-phase power switching control, including a common power supply, a backup power supply, two power modules, a common power selection module, a backup power selection module, a drive interlock module, a coil drive module, a common power sampling module, a backup power sampling module and an MCU module, wherein the common power supply and the backup power supply are respectively converted by independent power modules and then connected in parallel, and then connected to the MCU module after being connected in parallel. Compared with the prior art, the common power selection module and the backup power selection module of the control circuit of the present invention adopt bidirectional thyristors to control the AC380V voltage, so that the dual-power 3-pole product does not need to introduce an N line from the outside, which facilitates wiring in a power distribution cabinet, and adopts an AC380V power supply to improve the coil driving capability.

Description

Technical Field

[0001] The invention relates to the technical field of low-voltage electrical appliances, and in particular to a control circuit for dual-power three-phase power switching control. Background Art

[0002] Most existing technologies use double-pole double-throw relays to achieve drive power supply selection, but the maximum capacity of general-purpose relays on the market is mostly 277VAC / 8A, so there is a risk of burning the relay if used in a 380V power supply system. Therefore, when using the 3-pole dual-power products on the market, a separate N line needs to be pulled to connect the product, so as to achieve 220VAC power supply switching drive control and avoid relay burning, but the addition of the N line also increases the cost.

[0003] Therefore, the present invention needs to provide a device that can be used in a dual-power 380V power supply system without the need for an external N line, and that can improve the coil driving capability by using an AC380V power supply. Summary of the invention

[0004] The object of the present invention is to provide an electronic miniature circuit breaker circuit board to solve the above-mentioned problems existing in the prior art.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is as follows: A control circuit for dual-power three-phase power switching control, comprising a common power supply, a backup power supply, two power modules, a common power selection module, a backup power selection module, a drive interlock module, a coil drive module, a common power sampling module, a backup power sampling module and an MCU module, The common power supply and the backup power supply are respectively converted by independent power supply modules and then connected in parallel, and then connected to the MCU module; The common power sampling module and the backup power sampling module collect the three-line voltage of the common power supply and the backup power supply, and transmit the collected data to the MCU module; The drive interlock module is used to prevent the common power supply and the backup power supply from being driven at the same time, so as to avoid a short circuit between the two power supplies. The drive interlock module is located between the power selection module and the MCU module; The MCU module drives the coil driving module to open the common power supply of the main circuit and close the standby power supply, so that the subsequent loads of the dual-power main circuit can keep working without power failure.

[0006] Furthermore, the common power supply acquisition module includes three power supplies, each of which includes two-phase AL1H and AL2, AL2 and AL3, AL3 and AL1 circuits. The voltage difference between each two phases of each power supply is input to the operational amplifiers U13A, U13B, and U13C respectively, and is proportionally reduced to the detectable voltage range of 0-3.3V by the operational amplifier. The positive input terminal of the operational amplifier is raised by 1.65V, and the positive and negative half cycles of the sinusoidal signal are input to the MCU with 1.65V as the boundary; The backup power supply acquisition module includes three power supplies, each of which includes two-phase BL1H and BL2, BL2 and BL3, BL3 and BL1 circuits. The voltage difference between each two phases of each power supply is input to operational amplifiers U14A, U14B, and U14C respectively, and is proportionally reduced to a detectable voltage range of 0-3.3V by the operational amplifier. The positive input end of the operational amplifier is raised by 1.65V, and the positive and negative half cycles of the sinusoidal signal are input to the MCU with 1.65V as the boundary.

[0007] Furthermore, the common power selection module adopts U2 and U3 isolation optocoupler chips, bidirectional thyristors Q2 and Q5, NMOS tubes Q4 and Q8, and A power supplies L1 and L3 (or N) are respectively connected to one end of the thyristor Q2 and Q5. The single-chip microcomputer samples the voltage signals of the common power supply and the backup power supply to determine whether there is an abnormality, thereby driving the NMOS tube to turn on or off, driving the optocoupler to drive or disconnect the thyristor, and selecting a normal power supply for the subsequent drive circuit. The control signal controls the two thyristors at the same time to ensure the synchronization of the power supply; among them, R5 and R15 are varistors, which discharge the surge impact that may be generated from the outside to protect the thyristor; R8 and R18 are respectively Q4 and Q8 driving current limiting resistors; R4 and R13 are respectively U2 and U3 current limiting resistors; R2, R10, R11, and R19 are respectively thyristors Q2 and Q5 driving current limiting resistors.

[0008] Furthermore, the backup power selection module adopts U1 and U4 isolation optocoupler chips, bidirectional thyristors Q1 and Q6, NMOS tubes Q3 and Q7, and B power supplies L1 and L3 (or N) are respectively connected to one end of thyristors Q1 and Q6. The single-chip microcomputer samples the voltage signals of the common power supply and the backup power supply to determine whether there is an abnormality, thereby driving the NMOS tube to turn on or off, driving the optocoupler to drive or disconnect the thyristor, and selecting a normal power supply for the subsequent drive circuit. The control signal controls the two thyristors at the same time to ensure the synchronization of the power supply; among them, R6 and R16 are varistors, which discharge the surge impact that may be generated from the outside to protect the thyristor; R7 and R17 are Q3 and Q7 drive current limiting resistors respectively; R3 and R14 are U1 and U4 current limiting resistors respectively; R1, R19, R12, and R20 are thyristors Q1 respectively.

[0009] Furthermore, the drive interlock module adopts U5 and U6 AND gate logic devices to prevent the common power supply and the backup power supply from being driven at the same time, causing a short circuit between the two power supplies. The MCU module controls the high and low levels of CHOOSE_A / CHOOSE_B outputs: when CHOOSE_A outputs high and CHOOSE_B outputs low, U5 outputs a high level to drive the common power supply output, and U6 outputs a low level and does not drive; when CHOOSE_A outputs low and CHOOSE_B outputs high, U6 outputs a high level to drive the common power supply output, and U5 outputs a low level and does not drive; when CHOOSE_A outputs high and CHOOSE_B outputs high, U5 outputs a low level and does not drive, and U6 outputs a low level and does not drive; when CHOOSE_A outputs high and CHOOSE_B outputs high, U5 outputs a low level and does not drive, and U6 outputs a low level and does not drive; when CHOOSE_A outputs low and CHOOSE_B outputs low, U5 outputs a low level and does not drive, and U6 outputs a low level and does not drive.

[0010] Furthermore, the coil drive module: the dual power supply includes A closing drive coil, B closing drive coil, and opening drive coil, which are used to control normal closing, standby closing, and opening respectively.

[0011] Furthermore, the A closing drive coil circuit includes: isolation optocoupler U7, bidirectional thyristor Q10, varistor R25, rectifier bridge U8, resistors R26 / R24 / R31 / R28, capacitor C3, diode D1, and socket JP1 (connected to the drive coil); After the MCU control signal is converted, it controls the isolation optocoupler U7 and then drives the thyristor to turn on. Therefore, the power selected by the standby power selection module is passed through the rectifier bridge for full-wave rectification and then provided to the coil connected to the socket, driving the A closing coil to work. The resistor R28, capacitor C3 and diode D1 form an RCD absorption circuit to absorb the reverse electromotive force generated by the coil.

[0012] Furthermore, the B closing drive coil circuit includes: an isolation optocoupler U9, a bidirectional thyristor Q12, a varistor R27, a rectifier bridge U10, resistors R34 / R33 / R37 / R36, a capacitor C4, a diode D2, and a socket JP2 (connected to the drive coil); After the MCU control signal is converted, it controls the isolation optocoupler U9 and then drives the thyristor to turn on, so that the power selected by the standby power selection module is passed through the rectifier bridge for full-wave rectification and then provided to the coil connected to the socket, driving the A closing coil to work. The resistor R36, capacitor C4, and diode D2 form an RCD absorption circuit to absorb the reverse electromotive force generated by the coil.

[0013] Further, the opening gate drive coil circuit includes: an isolation optocoupler U11, a bidirectional thyristor Q13, a varistor R35, a rectifier bridge U12, resistors R39 / R38 / R42 / R41, a capacitor C5, a diode D3, and a seat JP3 (connected to the drive coil); After the MCU control signal is converted, it controls the isolation optocoupler U11 and then drives the thyristor to turn on. Therefore, the power selected by the standby power selection module is passed through the rectifier bridge for full-wave rectification and then provided to the coil connected to the socket, driving the A closing coil to work. The resistor R41, capacitor C5 and diode D3 form an RCD absorption circuit to absorb the reverse electromotive force generated by the coil.

[0014] Furthermore, the coil driving module uses a bidirectional thyristor to control the AC380V voltage.

[0015] Furthermore, the coil driving module is used to drive an excitation coil or a motor.

[0016] The beneficial effects of the present invention are: Since the common power selection module and the backup power selection module of the present invention use bidirectional thyristors to control the AC380V voltage, the dual-power 3-pole product does not need to introduce an N line from the outside, which facilitates wiring in the distribution cabinet. At the same time, the use of AC380V power can improve the coil driving capability. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a control circuit module diagram for dual power three-phase power switching control of the present invention; Figure 2 It is a circuit diagram of a commonly used voltage acquisition module of the present invention; Figure 3 It is a circuit diagram of the standby voltage acquisition module of the present invention; Figure 4 is a circuit diagram of a commonly used power selection module of the present invention; Figure 5 is a circuit diagram of a backup power supply selection module of the present invention; Figure 6 is a circuit diagram of a drive interlocking module of the present invention; Figure 7 It is a circuit diagram of the A closing drive coil of the present invention; Figure 8 It is a circuit diagram of the B closing drive coil of the present invention; Fig. 9 It is a circuit diagram of the opening drive coil of the present invention; Fig.10 It is a dual power supply switching control workflow diagram of the present invention. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation methods described herein are only used to explain the present invention and are not used to limit the present invention.

[0019] Among them, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention or simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0020] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0021] The word “exemplary” is used exclusively herein to mean “serving as an example, example, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.

[0022] In addition, in order to better illustrate the present application, numerous specific details are provided in the following specific embodiments. It should be understood by those skilled in the art that the present application can also be implemented without certain specific details. In some examples, methods, means, components and circuits well known to those skilled in the art are not described in detail in order to highlight the subject matter of the present application.

[0023] like Figures 1 to 10 As shown, the present invention relates to a control circuit for dual-power three-phase power switching control, including a common power supply, a backup power supply, two power modules, a common power selection module, a backup power selection module, a drive interlocking module, a coil drive module, a common power sampling module, a backup power sampling module and an MCU module. The common power supply and the backup power supply are respectively converted by independent power supply modules and then connected in parallel, and then connected to the MCU module; The common power sampling module and the backup power sampling module collect the three-line voltage of the common power supply and the backup power supply, and transmit the collected data to the MCU module; The drive interlock module is used to prevent the common power supply and the backup power supply from being driven at the same time, so as to avoid a short circuit between the two power supplies. The drive interlock module is located between the power selection module and the MCU module; The MCU module drives the coil driving module to open the common power supply of the main circuit and close the standby power supply, so that the subsequent loads of the dual-power main circuit can keep working without power failure.

[0024] From the above method, it can be seen that since the common power selection module and the backup power selection module use bidirectional thyristors to control the AC380V voltage, the dual-power 3-pole product does not need to introduce the N line from the outside, which facilitates the wiring in the distribution cabinet. At the same time, the use of AC380V power supply can improve the coil driving capability.

[0025] In this embodiment, the common power acquisition module includes three power supplies, each of which includes two-phase AL1H and AL2, AL2 and AL3, AL3 and AL1 circuits. The voltage difference between each two phases of each power supply is input to the operational amplifiers U13A, U13B, and U13C respectively, and is proportionally reduced to the MCU detectable voltage range of 0-3.3V through the operational amplifier. The positive input terminal of the operational amplifier is raised by 1.65V, and the positive and negative half cycles of the sinusoidal signal are input to the MCU with 1.65V as the boundary; The backup power supply acquisition module includes three power supplies, each of which includes two-phase BL1H and BL2, BL2 and BL3, BL3 and BL1 circuits. The voltage difference between each two phases of each power supply is input to operational amplifiers U14A, U14B, and U14C respectively, and is proportionally reduced to a detectable voltage range of 0-3.3V by the operational amplifier. The positive input end of the operational amplifier is raised by 1.65V, and the positive and negative half cycles of the sinusoidal signal are input to the MCU with 1.65V as the boundary.

[0026] Specifically, it should be noted that the common power selection module adopts U2 and U3 isolation optocoupler chips, bidirectional thyristors Q2 and Q5, NMOS tubes Q4 and Q8, and A power supplies L1 and L3 (or N) are respectively connected to one end of the thyristor Q2 and Q5. The single-chip microcomputer samples the voltage signals of the common power supply and the backup power supply to determine whether there is an abnormality, thereby driving the NMOS tube to turn on or off, driving the optocoupler to drive or disconnect the thyristor, and selecting a normal power supply for the subsequent drive circuit. The control signal controls the two thyristors at the same time to ensure the synchronization of the power supply; among them, R5 and R15 are varistors, which discharge the surge impact that may be generated from the outside to protect the thyristor; R8 and R18 are respectively Q4 and Q8 driving current limiting resistors; R4 and R13 are respectively U2 and U3 current limiting resistors; R2, R10, R11, and R19 are respectively thyristors Q2 and Q5 driving current limiting resistors.

[0027] Furthermore, the backup power selection module uses U1 and U4 isolation optocoupler chips, bidirectional thyristors Q1 and Q6, NMOS tubes Q3 and Q7, and B power supplies L1 and L3 (or N) are respectively connected to one end of thyristors Q1 and Q6. The single-chip microcomputer samples the voltage signals of the common power supply and the backup power supply to determine whether there is an abnormality, thereby driving the NMOS tube to turn on or off, driving the optocoupler to drive or disconnect the thyristor, and selecting a normal power supply for the subsequent drive circuit. The control signal controls the two thyristors at the same time to ensure the synchronization of the power supply; among them, R6 and R16 are varistors, which discharge the surge impact that may be generated from the outside to protect the thyristor; R7, R 17 are respectively Q3 and Q7 driving current limiting resistors; R3 and R14 are respectively U1 and U4 current limiting resistors; R1, R19, R12, R20 are respectively thyristor Q1. In the present embodiment, the power selection module is divided into a common power selection circuit and a backup power selection circuit, wherein each power selection circuit is divided into two bidirectional thyristor control circuits, which respectively control L1 and L3 to be turned on or off, and the two controls are controlled by the same control signal to ensure the synchronization of the switches as much as possible; the two power selection drive signals are interlocked with the AND gate logic gate, and the two signals cannot be driven at the same time to prevent the two power supplies from being short-circuited and burning the controller or load devices.

[0028] Specifically, the coil drive module: the dual power supply includes A closing drive coil, B closing drive coil, and opening drive coil, which are respectively used to control normal closing, standby closing, and opening, and the power supply output by the power selection module is controlled by connecting or disconnecting one of the live wires through a bidirectional thyristor to provide energy for the drive unit.

[0029] Furthermore, the A closing drive coil circuit includes: isolation optocoupler U7, bidirectional thyristor Q10, varistor R25, rectifier bridge U8, resistors R26 / R24 / R31 / R28, capacitor C3, diode D1, and socket JP1 (connected to the drive coil); After the MCU control signal is converted, it controls the isolation optocoupler U7 and then drives the thyristor to turn on. Therefore, the power selected by the standby power selection module is passed through the rectifier bridge for full-wave rectification and then provided to the coil connected to the socket, driving the A closing coil to work. The resistor R28, capacitor C3 and diode D1 form an RCD absorption circuit to absorb the reverse electromotive force generated by the coil.

[0030] Furthermore, the B closing drive coil circuit includes: an isolation optocoupler U9, a bidirectional thyristor Q12, a varistor R27, a rectifier bridge U10, resistors R34 / R33 / R37 / R36, a capacitor C4, a diode D2, and a socket JP2 (connected to the drive coil); After the MCU control signal is converted, it controls the isolation optocoupler U9 and then drives the thyristor to turn on, so that the power selected by the standby power selection module is passed through the rectifier bridge for full-wave rectification and then provided to the coil connected to the socket, driving the A closing coil to work. The resistor R36, capacitor C4, and diode D2 form an RCD absorption circuit to absorb the reverse electromotive force generated by the coil.

[0031] Further, the opening gate drive coil circuit includes: an isolation optocoupler U11, a bidirectional thyristor Q13, a varistor R35, a rectifier bridge U12, resistors R39 / R38 / R42 / R41, a capacitor C5, a diode D3, and a seat JP3 (connected to the drive coil); After the MCU control signal is converted, it controls the isolation optocoupler U11 and then drives the thyristor to turn on. Therefore, the power selected by the standby power selection module is passed through the rectifier bridge for full-wave rectification and then provided to the coil connected to the socket, driving the A closing coil to work. The resistor R41, capacitor C5 and diode D3 form an RCD absorption circuit to absorb the reverse electromotive force generated by the coil.

[0032] It is also worth mentioning that the coil drive module uses a bidirectional thyristor to control the AC380V voltage. In actual use, it can be used in working environments such as AC220V and AC380V according to bidirectional thyristors with different parameters. The coil drive module is used to drive the excitation coil or the motor.

[0033] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be considered as the scope of protection of the present invention.

Claims

1. A control circuit for dual power three-phase power switching control, characterized in that: It includes a normal power supply, a backup power supply, two power supply modules, a normal power supply selection module, a backup power supply selection module, a drive interlock module, a coil drive module, a normal power supply sampling module, a backup power supply sampling module and an MCU module. The common power supply and the backup power supply are respectively converted by independent power supply modules and then connected in parallel, and then connected to the MCU module; The common power sampling module and the backup power sampling module collect the three-line voltage of the common power supply and the backup power supply, and transmit the collected data to the MCU module; The drive interlock module is used to prevent the common power supply and the backup power supply from being driven at the same time, so as to avoid a short circuit between the two power supplies. The drive interlock module is located between the power selection module and the MCU module; The MCU module drives the coil driving module to open the common power supply of the main circuit and close the standby power supply, so that the subsequent loads of the dual-power main circuit can keep working without power failure.

2. The control circuit for dual-power three-phase power switching control according to claim 1, characterized in that: The commonly used power supply acquisition module includes three power supplies, each of which includes two-phase AL1H and AL2, AL2 and AL3, AL3 and AL1 circuits. The voltage difference between each two phases of each power supply is input to the operational amplifiers U13A, U13B, and U13C respectively, and is proportionally reduced to the MCU detectable voltage range of 0-3.3V through the operational amplifier. The positive input terminal of the operational amplifier is raised by 1.65V, and the positive and negative half cycles of the sinusoidal signal are input to the MCU with 1.65V as the boundary; The backup power supply acquisition module includes three power supplies, each of which includes two-phase BL1H and BL2, BL2 and BL3, BL3 and BL1 circuits. The voltage difference between each two phases of each power supply is input to operational amplifiers U14A, U14B, and U14C respectively, and is proportionally reduced to a detectable voltage range of 0-3.3V by the operational amplifier. The positive input end of the operational amplifier is raised by 1.65V, and the positive and negative half cycles of the sinusoidal signal are input to the MCU with 1.65V as the boundary.

3. The control circuit for dual-power three-phase power switching control according to claim 1, characterized in that: The common power selection module adopts U2 and U3 isolation optocoupler chips, bidirectional thyristors Q2 and Q5, NMOS tubes Q4 and Q8, and A power supplies L1 and L3 (or N) are respectively connected to one end of thyristors Q2 and Q5. The single-chip microcomputer samples the voltage signals of the common power supply and the backup power supply to determine whether there is an abnormality, thereby driving the NMOS tube to turn on or off, driving the optocoupler to drive or disconnect the thyristor, and selecting a normal power supply for the subsequent drive circuit. The control signal controls the two thyristors at the same time to ensure the synchronization of the power supply; among them, R5 and R15 are varistors, which discharge the surge impact that may be generated from the outside to protect the thyristor; R8 and R18 are respectively Q4 and Q8 driving current limiting resistors; R4 and R13 are respectively U2 and U3 current limiting resistors; R2, R10, R11, and R19 are respectively thyristors Q2 and Q5 driving current limiting resistors.

4. The control circuit for dual-power three-phase power switching control according to claim 1, characterized in that: The backup power selection module adopts U1 and U4 isolation optocoupler chips, bidirectional thyristors Q1 and Q6, NMOS tubes Q3 and Q7, and B power supplies L1 and L3 (or N) are respectively connected to one end of thyristors Q1 and Q6. The single-chip microcomputer samples the voltage signals of the common power supply and the backup power supply to determine whether there is an abnormality, thereby driving the NMOS tube to turn on or off, driving the optocoupler to drive or disconnect the thyristor, and selecting a normal power supply for the subsequent drive circuit. The control signal controls the two thyristors at the same time to ensure the synchronization of the power supply; among them, R6 and R16 are varistors, which discharge the surge impact that may be generated from the outside to protect the thyristor; R7 and R17 are respectively Q3 and Q7 driving current limiting resistors; R3 and R14 are respectively U1 and U4 current limiting resistors; R1, R19, R12, and R20 are respectively thyristors Q1.

5. The control circuit for dual-power three-phase power switching control according to claim 1, characterized in that: The drive interlock module uses U5 and U6 AND gate logic devices to prevent the common power supply and the backup power supply from being driven at the same time, causing a short circuit between the two power supplies. The MCU module controls the high and low levels of CHOOSE_A / CHOOSE_B outputs: when CHOOSE_A outputs high and CHOOSE_B outputs low, U5 outputs a high level to drive the common power supply output, and U6 outputs a low level and does not drive; when CHOOSE_A outputs low and CHOOSE_B outputs high, U6 outputs a high level to drive the common power supply output, and U5 outputs a low level and does not drive; when CHOOSE_A outputs high and CHOOSE_B outputs high, U5 outputs a low level and does not drive, and U6 outputs a low level and does not drive; when CHOOSE_A outputs high and CHOOSE_B outputs high, U5 outputs a low level and does not drive, and U6 outputs a low level and does not drive; when CHOOSE_A outputs low and CHOOSE_B outputs low, U5 outputs a low level and does not drive, and U6 outputs a low level and does not drive.

6. The control circuit for dual-power three-phase power switching control according to claim 1, characterized in that: The coil drive module: The dual power supply includes A closing drive coil, B closing drive coil and opening drive coil, which are used to control the normal closing, standby closing and opening respectively.

7. The control circuit for dual-power three-phase power switching control according to claim 6, characterized in that: The A closing drive coil circuit includes: an isolation optocoupler U7, a bidirectional thyristor Q10, a varistor R25, a rectifier bridge U8, resistors R26 / R24 / R31 / R28, a capacitor C3, a diode D1, and a socket JP1 (connected to the drive coil); After the MCU control signal is converted, it controls the isolation optocoupler U7 and then drives the thyristor to turn on. Therefore, the power selected by the standby power selection module is passed through the rectifier bridge for full-wave rectification and then provided to the coil connected to the socket, driving the A closing coil to work. The resistor R28, capacitor C3 and diode D1 form an RCD absorption circuit to absorb the reverse electromotive force generated by the coil.

8. The control circuit for dual-power three-phase power switching control according to claim 6, characterized in that: The B closing drive coil circuit includes: an isolation optocoupler U9, a bidirectional thyristor Q12, a varistor R27, a rectifier bridge U10, resistors R34 / R33 / R37 / R36, a capacitor C4, a diode D2, and a seat JP2 (connected to the drive coil); After the MCU control signal is converted, it controls the isolation optocoupler U9 and then drives the thyristor to turn on, so that the power selected by the standby power selection module is passed through the rectifier bridge for full-wave rectification and then provided to the coil connected to the socket, driving the A closing coil to work. The resistor R36, capacitor C4, and diode D2 form an RCD absorption circuit to absorb the reverse electromotive force generated by the coil.

9. The control circuit for dual-power three-phase power switching control according to claim 6, characterized in that: The opening gate drive coil circuit includes: an isolation optocoupler U11, a bidirectional thyristor Q13, a varistor R35, a rectifier bridge U12, resistors R39 / R38 / R42 / R41, a capacitor C5, a diode D3, and a seat JP3 (connected to the drive coil); After the MCU control signal is converted, it controls the isolation optocoupler U11 and then drives the thyristor to turn on. Therefore, the power selected by the standby power selection module is passed through the rectifier bridge for full-wave rectification and then provided to the coil connected to the socket, driving the A closing coil to work. The resistor R41, capacitor C5 and diode D3 form an RCD absorption circuit to absorb the reverse electromotive force generated by the coil.

10. The control circuit for dual-power three-phase power switching control according to claim 6, characterized in that: The coil driving module adopts a bidirectional thyristor to control the AC380V voltage, and the coil driving module is used to drive an excitation coil or a motor.

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