Magnetic control alternating current contactor and control module thereof

Abstract

The invention provides a magnetic control alternating current contactor and a control module thereof. In the magnetic control alternating current contactor, an iron core of an electromagnetic system is made of semi-hard magnetic alloy steel, a control module is used for controlling a magnet exciting coil in the electromagnetic system to generate a forward electromagnetic field, the magnetic control alternating current contactor is used for closing, a semi-hard magnetic alloy steel core is magnetized, a closing state is kept by a retention force generated by residual magnetism, and the magnet exciting coil does not need to be electrified for a long time; and the magnet exciting coil is controlled to generate a reverse electromagnetic field, the semi-hard magnetic alloy steel core is demagnetized, the magnetic force disappears, and the magnetic control alternating current contactor is switched off under the action of the spring. Besides action output, the control module only consumes a small amount of power, and the overall holding power consumption of the magnetic control alternating current contactor is close to zero and is superior to the national standard I-level energy efficiency requirement.

Description

Technical Field

[0001] The present invention belongs to the fields of energy conservation and environmental protection, new energy, and low-voltage control electrical appliances, and particularly relates to the field of energy-saving AC contactors. Background Art

[0002] With the booming development of the automation industry, artificial intelligence, and control technology, control electrical appliances play an extremely important role and are widely used. As a control electrical appliance, an AC contactor can be used to frequently connect or disconnect various terminal electrical appliances over a long distance. In daily life, it can be used for the control of common devices such as motors, transformers, lighting, and household appliances (refrigerators, air conditioners, washing machines), covering a wide range of application fields and playing a very important role in social life and economic development. Currently, AC contactors have high energy consumption, are prone to heat generation, and produce a lot of noise, consuming a large amount of electrical energy during long-term operation. According to authoritative statistics, the annual energy consumption of global AC contactors is more than 2 trillion kWh.

[0003] In this regard, in order to provide guarantee for the green development of the national economy, China implemented the new version of the mandatory standard "GB21518-2022, Energy Efficiency Limits and Energy Efficiency Grades for AC Contactors" as of January 1, 2024.

[0004] In terms of the energy-saving technology of AC contactors, so far, there is a Chinese patent number CN1107963C (mechanical self-locking AC contactor), which uses a mechanical self-locking and electromagnetic unlocking method to lock the contacts of the AC contactor in the closed state to achieve the purpose of energy conservation. Its disadvantages are complex structure, large scope of product modification, high modification cost, and inability to automatically disconnect in case of sudden power failure of the power grid, resulting in certain safety problems. Similarly, Chinese patent number ZL200820302979.8 (energy-saving device for AC contactors) uses the principle of starting with DC high voltage and operating with DC low voltage to achieve the purpose of energy conservation. Its disadvantages are high cost, easy aging of electronic components, and unsuitability for use in high-temperature and high-humidity environments. In Chinese patent number 201420101284.9 (an energy-saving AC contactor), one iron core is a permanent magnet, and the other iron core is a soft magnet and is wound with a coil that generates a reverse magnetic flux. The permanent magnet is used to lock the contacts of the contactor in the closed state to achieve the purpose of energy conservation. When it is necessary to restore the contactor to its initial state, the coil in the soft iron core is energized to generate a reverse magnetic flux that repels the permanent magnet, causing it to return to its original position under the action of the return spring. Its disadvantages are easy demagnetization of the permanent magnet, easy generation of residual magnetism in the soft iron, simple and rough electronic circuit, high failure rate, and potential safety problems if the release circuit fails. Summary of the Invention

[0005] To solve the above problems, the present invention provides a magnetically controlled AC contactor and its control module. The core material of the electromagnetic system is semi-hard magnetic alloy steel. In the electromagnetic system, the exciting coil generates a forward electromagnetic field through a forward pulse current, causing the magnetically controlled AC contactor to close and magnetizing the semi-hard magnetic alloy steel core. The holding force is generated by the residual magnetism of the semi-hard magnetic alloy steel core to maintain the closed state, and the exciting coil does not need to be energized continuously. The exciting coil generates a reverse electromagnetic field through a reverse pulse current, demagnetizing the semi-hard magnetic alloy steel core and causing the magnetic force to disappear. Under the action of the spring, the magnetically controlled AC contactor opens. Thus, in the closed state, the magnetically controlled AC contactor does not continuously consume energy. The control power supply controls the closing and opening of the magnetically controlled AC contactor through the control module. Except for the action output, the control module has only a small amount of power consumption. The overall holding power consumption of the magnetically controlled AC contactor is less than 0.1W, approaching zero power consumption, far superior to the Class I energy efficiency requirements in "GB 21518-2022 Energy Efficiency Limits and Energy Efficiency Grades for AC Contactors".

[0006] In the present invention, the terms with directional expressions, including forward pulse current, reverse pulse current, forward electromagnetic field, reverse electromagnetic field, forward loading, and reverse loading, the forward and reverse directions therein are only for the convenience of expressing the corresponding logical relationships and do not represent their specific directions.

[0007] The implementation scheme of the present invention is as follows: A magnetically controlled AC contactor and its control module, including an electromagnetic system, a contact system, an arc extinguishing system, a spring, and a housing, and further including the control module. Among them, the electromagnetic system includes a static core, a moving core, and an exciting coil. One or both of the static core and the moving core are made of semi-hard magnetic alloy steel material. The exciting coil is arranged between the static core and the moving core to form a magnetically controlled electromagnetic system. The contact system includes a static contact and a moving contact. The moving core is connected to the moving contact and the spring. The control power supply is connected to the exciting coil through the control module to control the action of the magnetically controlled AC contactor, completely replacing the electromagnetic AC contactor.

[0008] Optionally, in the electromagnetic system, there are three combination forms of the moving core and the static core materials, namely: the first, both the static core and the moving core are made of semi-hard magnetic alloy steel material; the second, the static core is made of semi-hard magnetic alloy steel material and the moving core is made of soft magnetic material; the third, the static core is made of soft magnetic material and the moving core is made of semi-hard magnetic alloy steel material. The residual magnetism Br of the semi-hard magnetic alloy steel material is between 1T and 2T, the coercive force Hc is between 0.8KA / m and 20KA / m, and the demagnetization temperature is greater than 200°C.

[0009] Among them, the control module includes a power supply circuit, a voltage sampling circuit, a fraction sampling circuit, a single-chip microcomputer system, a closing signal isolation circuit, a tripping signal isolation circuit, and a bridge drive circuit; the control power supply generates a control power supply voltage signal through the voltage sampling circuit, and the control power supply voltage signal is measured by the single-chip microcomputer system. According to the control logic of the single-chip microcomputer system, two closing pulse control signals or two tripping pulse control signals are generated. The two closing pulse control signals and the two tripping pulse control signals are respectively connected to the bridge drive circuit through the closing signal isolation circuit and the tripping signal isolation circuit. The two closing pulse control signals control the bridge drive circuit to output a positive pulse current through the exciting coil, and the two tripping pulse control signals control the bridge drive circuit to output a negative pulse current through the exciting coil; the control power supply generates a system power supply and a drive power supply through the power supply circuit. The system power supply supplies power to the voltage sampling circuit, the fraction sampling circuit, the single-chip microcomputer system, the closing signal isolation circuit, and the tripping signal isolation circuit; the drive power supply supplies power to the bridge drive circuit; the single-chip microcomputer system is connected to the fraction switch signal of the magnetically controlled AC contactor through the fraction sampling circuit.

[0010] Among them, the voltage sampling circuit includes: a sampling capacitor C2, a current transformer T1, a load resistor R1, a resistor R2, a capacitor C3, a diode D1, and a diode D2; the control power supply generates a primary coil current through the series circuit composed of the sampling capacitor C2 and the primary of the current transformer T1. The secondary of the current transformer T1 outputs a secondary coil current related to the control power supply voltage, and the secondary coil current generates a voltage signal through the load resistor R1; the system power supply forms a series voltage dividing circuit through the diode D1, the diode D2, and the resistor R2. The resistor R2 divides the voltage as a reference voltage source. The capacitor C3 is connected in parallel with the resistor R2. The reference voltage source is connected to one end of the load resistor R1, and a measurable control power supply voltage signal obtained by adding the reference voltage source and the voltage signal is generated at the other end of the load resistor R1.

[0011] Among them, the bridge drive circuit consists of four switching tubes, namely a switching tube G1, a switching tube G2, a switching tube G3, and a switching tube G4. The four switching tubes and the exciting coil are connected to form an H-shaped bridge circuit; the two closing pulse control signals respectively control the switching tubes G2 and G4 to conduct, and the drive power supply conducts through the series circuit of the switching tube G2, the exciting coil, and the switching tube G4, and the exciting coil passes through a positive pulse current; the two tripping pulse control signals respectively control the switching tubes G1 and G3 to conduct, and the drive power supply conducts through the series circuit of the switching tube G1, the exciting coil, and the switching tube G3, and the exciting coil passes through a negative pulse current.

[0012] Among them, the pulse width of the forward pulse current is equal to the minimum time required for the reliable closing of the magnetically controlled AC contactor plus 2 ms; the pulse width of the reverse pulse current is equal to the minimum time required for the reliable opening of the magnetically controlled AC contactor plus 0.5 ms.

[0013] Among them, the control logic of the single-chip microcomputer system is as follows: in the open state of the magnetically controlled AC contactor, when the control power supply voltage is greater than the closing voltage threshold, the single-chip microcomputer system outputs two closing pulse control signals; in the closed state of the magnetically controlled AC contactor, when the control power supply voltage is less than the opening voltage threshold, the single-chip microcomputer system outputs two opening pulse control signals; the closing voltage threshold is equal to 85% of the rated working voltage of the excitation coil in the magnetically controlled AC contactor; the opening voltage threshold is equal to 50% of the rated working voltage of the excitation coil in the magnetically controlled AC contactor. Description of the Drawings

[0014] Figure 1 Embodiment: Schematic diagram of the structure of a magnetically controlled AC contactor and its control module.

[0015] Figure 2 Embodiment: Circuit block diagram of a magnetically controlled AC contactor and its control module.

[0016] Figure 3 Embodiment: Circuit diagram of the control power supply voltage sampling.

[0017] Figure 4 Embodiment: Circuit diagram of the bridge drive of the excitation coil. Detailed Embodiment

[0018] To more clearly illustrate the solution and beneficial effects of the present invention, the embodiments of the present invention will be further described in detail below in conjunction with the drawings. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work belong to the scope of protection of the present invention.

[0019] Comparison Figure 1 , for the NXC-65 electromagnetic AC contactor of the CHINT brand, its energy consumption is level 3, and the holding power consumption is close to 50 W. We changed the static iron core in its electromagnetic system to a semi-hard magnetic alloy material, the material of which is Cr12 alloy steel, composition: iron 73% - 85%, carbon 2.00% - 2.30%, silicon ≤ 0.4%, manganese ≤ 0.4%, deuterium 0.02%, sulfur ≤ 0.03%, chromium 11.5% - 13.00%, copper ≤ 0.30%; added a magnetically controlled AC contactor control module to form a new magnetically controlled AC contactor.

[0020] Comparison Figure 1 , Figure 2, in this embodiment, the structure of a magnetically controlled AC contactor and its control module is similar to that of a traditional electromagnetic AC contactor, including a housing 1, an electromagnetic system 2, a contact system 3, an arc extinguishing system 4, and a spring 5; it also includes a control module 6; the electromagnetic system 2 includes a static iron core 21, a moving iron core 22, and an exciting coil 23; the exciting coil 23 is arranged between the static iron core 21 and the moving iron core 22, and one or both of the static iron core 21 and the moving iron core 22 are made of semi-hard magnetic alloy steel material to form a magnetically controlled electromagnetic system; the contact system 3 includes a static contact 31 and a moving contact 32; the moving iron core 22 is connected to the moving contact 32 and the spring 5; the control power supply is connected to the exciting coil 23 through the control module 6 to control the operation of the magnetically controlled AC contactor, completely replacing the electromagnetic AC contactor.

[0021] Of course, in the electromagnetic system of the magnetically controlled AC contactor, there can be three combinations of the materials of the static iron core 21 and the moving iron core 22. The first is that both the static iron core 21 and the moving iron core 22 are made of semi-hard magnetic alloy steel material; the second is that the static iron core 21 is made of semi-hard magnetic alloy steel material and the moving iron core 22 is made of soft magnetic material; the third is that the static iron core 21 is made of soft magnetic material and the moving iron core 22 is made of semi-hard magnetic alloy steel material.

[0022] In the electromagnetic system of the traditional electromagnetic AC contactor, both the moving iron core and the static iron core are made of soft magnetic materials. Relying on the electromagnetic field generated by the current in the exciting coil, the moving iron core and the static iron core are attracted. In order to maintain the attracted state of the moving and static iron cores, the exciting coil must maintain a certain current. Therefore, the traditional electromagnetic AC contactor has a large holding energy consumption. Moreover, the exciting coil generates a large noise and heat during long-term energization, affecting the service life of the AC contactor.

[0023] In the past, semi-hard magnetic alloy steel materials were classified as permanent magnetic materials. However, compared with the characteristics of the currently widely used permanent magnetic materials, there are obvious differences, mainly manifested as the coercivity of the semi-hard magnetic alloy steel materials is relatively small, and their application fields and application methods are also completely different. Therefore, in some materials, semi-hard magnetic materials are directly separated from permanent magnetic materials and classified separately. In this embodiment, the remanence Br of the selected semi-hard magnetic alloy steel material is between 1T and 2T, the coercivity Hc is between 0.8KA / m and 20KA / m, and the demagnetization temperature is greater than 200°C.

[0024] In this embodiment, in the magnetically controlled AC contactor and its control module, the iron core of the electromagnetic system 2 is made of semi-hard magnetic alloy steel material. When closing, the exciting coil 23 is energized forward, and the generated forward electromagnetic field can magnetize the semi-hard magnetic alloy steel iron core. After the current in the exciting coil 23 stops, the semi-hard magnetic alloy steel iron core has remanence, and the remanent magnetic field can ensure that the moving iron core 22 and the static iron core 21 are maintained in the attracted state. When opening, the exciting coil 23 is energized backward, and the generated backward electromagnetic field can demagnetize the semi-hard magnetic alloy steel iron core. After the iron core is demagnetized, it loses its magnetic force, and the moving iron core 22 leaves the static iron core 21 under the action of the spring 5. At this time, the iron core returns to the non-magnetic state.

[0025] Obviously, in this embodiment, in the holding state, the exciting coil 23 does not need to continuously maintain current passing through, and the holding is power-free, does not generate heat, and there is no noise field, which has obvious beneficial effects.

[0026] Of course, to magnetize the semi-hard magnetic alloy steel core, the exciting coil 23 needs to generate a sufficient electromagnetic field intensity; and to demagnetize the magnetized semi-hard magnetic alloy steel core and prevent it from being magnetized again, the exciting coil 23 needs to generate an appropriate reverse electromagnetic field intensity.

[0027] According to the working characteristics of the electromagnetic system 2 of the magnetically controlled AC contactor, a control module 6 is added to the magnetically controlled AC contactor in this embodiment. The control power supply is connected to the control module 6, and the control module 6 outputs current, which passes through the exciting coil 23 to control the closing or opening action of the magnetically controlled AC contactor.

[0028] The control module 6 includes a power supply circuit 61, a voltage sampling circuit 62, a position sampling circuit 63, a single-chip microcomputer system 64, a closing signal isolation circuit 65, a tripping signal isolation circuit 66, and a bridge drive circuit 67; the control power supply generates a control power supply voltage signal through the voltage sampling circuit 62, and the control power supply voltage signal is measured by the single-chip microcomputer system 64. According to the control logic of the single-chip microcomputer system, two closing pulse control signals or two tripping pulse control signals are generated. The two closing pulse control signals and the two tripping pulse control signals are respectively connected to the bridge drive circuit 67 through the closing signal isolation circuit 65 and the tripping signal isolation circuit 66. The two closing control signals control the bridge drive circuit 67 to output a positive pulse current through the exciting coil 23, and the two tripping control signals control the bridge drive circuit 67 to output a reverse pulse current through the exciting coil 23; the control power supply generates a system power supply and a drive power supply through the power supply circuit 61. The system power supply supplies power to the voltage sampling circuit 62, the position sampling circuit 63, the single-chip microcomputer system 64, the closing signal isolation circuit 65, and the tripping signal isolation circuit 66; the drive power supply supplies power to the bridge drive circuit 67; the single-chip microcomputer system 64 is connected to the position switch signal of the magnetically controlled AC contactor through the position sampling circuit 63.

[0029] The control power supply for controlling the action of the AC contactor is mainly an AC power supply, such as: AC24V, AC48V, AC110, AC220V or AC380V. The electrical equipment actually connected to these power supplies is very complex and usually has strong interference signals; therefore, to ensure the working stability and long-term reliability of the control module 6; in this embodiment, corresponding isolation measures are taken for the circuits connected to the single-chip microcomputer system 64. Specifically: the position sampling circuit 63, the closing signal isolation circuit 65, and the tripping signal isolation circuit 66 use optocoupler isolation; the power supply circuit 61 is provided with appropriate energy storage capacitors, and an isolation transformer is used to generate the system power supply; for comparison Figure 3, the voltage sampling circuit 62 is isolated by a current transformer T1, and also includes a sampling capacitor C2, a load resistor R1, a resistor R2, a capacitor C3, a diode D1, and a diode D2; the control power supply generates a primary coil current through the series circuit composed of the sampling capacitor C2 and the primary of the current transformer T1, and the secondary of the current transformer T1 outputs a secondary coil current related to the control power supply voltage, and the secondary coil current generates a voltage signal through the load resistor R1; the system power supply forms a series voltage dividing circuit through the diode D1, the diode D2, and the resistor R2, and the resistor R2 divides the voltage as a reference voltage source. The capacitor C3 is connected in parallel with the resistor R2, and the reference voltage source is connected to one end of the load resistor R1, and a measurable control power supply voltage signal obtained by adding the reference voltage source and the voltage signal is generated at the other end of the load resistor R1.

[0030] In addition, compared with Figure 4 , the bridge drive circuit 67 in the control module 6 is composed of four switching tubes, namely a switching tube G1, a switching tube G2, a switching tube G3, and a switching tube G4. MOS tubes are used as switching tubes, and the four switching tubes are connected to the excitation coil 23 to form an H-shaped bridge circuit; the two closing pulse control signals respectively control the switching tube G2 and the switching tube G4 to conduct, and the drive power supply conducts through the series circuit of the switching tube G2, the excitation coil 23, and the switching tube G4, and the excitation coil 23 passes through a positive pulse current; the two opening pulse control signals respectively control the switching tube G1 and the switching tube G3 to conduct, and the drive power supply conducts through the series circuit of the switching tube G1, the excitation coil 23, and the switching tube G3, and the excitation coil 23 passes through a reverse pulse current.

[0031] In order to accurately control the closing and opening actions of the magnetically controlled AC contactor, compared with Figure 2 , in this embodiment, through the single-chip microcomputer system in the control module 6, the following control logic and process are adopted.

[0032] a When the control power supply for externally controlling the closing of the magnetically controlled AC contactor is powered on, the connected control module 6 obtains power, and the internal single-chip microcomputer system 63 starts and initializes the port settings and the state settings of the magnetically controlled AC contactor. Here, the magnetically controlled AC contactor is set to the open state.

[0033] b If the magnetically controlled AC contactor is in the open state, the control module 6 continuously detects the control power supply voltage numerical information through the A / D conversion circuit, calculates the effective value of the control power supply voltage. When the effective value of the control power supply voltage is greater than the closing voltage threshold, a closing instruction is executed, and the magnetically controlled AC contactor performs a closing action, and the magnetically controlled AC contactor is set to the closed state. Here, the closing voltage threshold is equal to 85% of the rated working voltage of the excitation coil 23 in the magnetically controlled AC contactor.

[0034] c If the magnetically controlled AC contactor is in the closed state, the control module 6 continuously detects the numerical information of the control power supply voltage through the A / D conversion circuit and calculates the effective value of the control power supply voltage; when the control power supply loses power and the effective value of the control power supply voltage is less than the tripping voltage threshold, a tripping instruction is executed, and the magnetically controlled AC contactor performs a tripping action, setting the magnetically controlled AC contactor to the tripping state. Here, the tripping voltage threshold is equal to 50% of the rated working voltage of the excitation coil in the magnetically controlled AC contactor.

[0035] Among them, the process of executing the closing instruction is as follows: In the magnetically controlled AC contactor, the single-chip microcomputer system of the control module 6 outputs two-way closing pulse control signals, outputs a positive pulse current through the bridge drive circuit 67, and the positive pulse current generates a positive electromagnetic field through the excitation coil 23. Under the action of the positive electromagnetic field, the moving iron core 22 moves towards the static iron core 21 for suction. After the moving iron core 22 and the static iron core 21 are attracted, a closed magnetic circuit is formed; at the same time, the semi-hard magnetic alloy steel core is magnetized by the positive electromagnetic field; after the positive pulse current stops, the suction force generated by the residual magnetism of the semi-hard magnetic alloy steel core makes the static iron core 21 and the moving iron core 22 overcome the spring force and maintain the suction state; the moving iron core 22 drives the moving contact 32 to compress the spring 5; the magnetically controlled AC contactor generates a closing action and remains in the closed state. The duration of the positive pulse current is equal to the minimum time required for the reliable closing of the magnetically controlled AC contactor plus 2 ms.

[0036] Among them, the process of executing the tripping instruction is as follows: In the magnetically controlled AC contactor, the single-chip microcomputer system of the control module 6 outputs two-way tripping pulse control signals, outputs a reverse pulse current through the bridge drive circuit 67, and the reverse pulse current generates a reverse electromagnetic field through the excitation coil 23. Under the action of the reverse magnetic field, the semi-hard magnetic alloy steel core demagnetizes, the magnetic force disappears, and the moving iron core 22 leaves the static iron core 21 under the action of the spring force, and the moving iron core 22 drives the moving contact 32; the magnetically controlled AC contactor generates a tripping action; the duration of the reverse pulse current is equal to the minimum time required for the reliable tripping of the magnetically controlled AC contactor plus 0.5 ms.

[0037] According to the above control logic and process, when the external control power supply voltage is greater than 85% of the rated working voltage of the excitation coil 23 of the magnetically controlled AC contactor, upon power-on, the control module 6 is started. At the same time, when it is detected that the control power supply voltage meets the closing start condition, a positive pulse current is output, and the magnetically controlled AC contactor is controlled to perform a closing operation through the electromagnetic system 2; when the control power supply remains powered on, the magnetically controlled AC contactor remains in the closed state. At this time, no current passes through the excitation coil 23, and no electric energy is consumed. Only the control module 6 consumes a small amount of static power consumption, which is less than 0.1 W. When the external control power supply loses power, the control module 6 continues to operate using the electric quantity of the energy storage capacitor in the power supply circuit 62. When it is detected that the control power supply voltage is less than 50% of the rated working voltage of the excitation coil 23, a reverse pulse current is output, and the magnetically controlled AC contactor is controlled to perform a tripping operation through the electromagnetic system 2.

[0038] From the description of the above embodiments, it can be seen that for the magnetically controlled AC contactor and its control module, the control power supply controls the closing or tripping of the magnetically controlled AC contactor through the control module, and the purposes of low power consumption, low noise, full isolation, anti-interference, safety, and reliability can be achieved.

Claims

1. A magnetically controlled AC contactor and its control module, comprising an electromagnetic system, a contact system, an arc extinguishing system, a spring and a housing, characterized in that One or both of the static iron core and the moving iron core in the electromagnetic system are made of semi-hard magnetic alloy steel material, and together with the excitation coil, they form a magnetically controlled electromagnetic system. A control module is added, and the control power supply is connected to the excitation coil through the control module to control the operation of the AC contactor, completely replacing the electromagnetic AC contactor.

2. The magnetically controlled AC contactor and its control module according to claim 1, characterized in that There are three combinations of the materials of the moving iron core and the static iron core in the electromagnetic system, namely: First, both the static iron core and the moving iron core are made of semi-hard magnetic alloy steel material; Second, the static iron core is made of semi-hard magnetic alloy steel material and the moving iron core is made of soft magnetic material; Third, the static iron core is made of soft magnetic material and the moving iron core is made of semi-hard magnetic alloy steel material; The remanence Br of the semi-hard magnetic alloy steel material is between 1T and 2T, and the coercive force Hc is between 0.8KA / m and 20KA / m.

3. The magnetically controlled AC contactor and its control module according to claim 1, characterized in that The control module includes a power supply circuit, a voltage sampling circuit, a position sampling circuit, a single-chip microcomputer system, a closing signal isolation circuit, a tripping signal isolation circuit, and a bridge drive circuit; The control power supply generates a control power supply voltage signal through the voltage sampling circuit. The control power supply voltage signal is measured by the single-chip microcomputer system. According to the control logic of the single-chip microcomputer system, two closing pulse control signals or two tripping pulse control signals are output. The two closing pulse control signals and the two tripping pulse control signals respectively pass through the closing signal isolation circuit and the tripping signal isolation circuit to connect to the bridge drive circuit. The two closing pulse control signals control the bridge drive circuit to output a positive pulse current through the excitation coil, and the two tripping pulse control signals control the bridge drive circuit to output a reverse pulse current through the excitation coil; The control power supply generates a system power supply and a drive power supply through the power supply circuit. The system power supply supplies power to the voltage sampling circuit, the position sampling circuit, the single-chip microcomputer system, the closing signal isolation circuit, and the tripping signal isolation circuit; The drive power supply supplies power to the bridge drive circuit; The single-chip microcomputer system is connected to the position switch signal of the magnetically controlled AC contactor through the position sampling circuit.

4. The magnetically controlled AC contactor and its control module according to claim 1, characterized in that The voltage sampling circuit includes: a sampling capacitor C2, a current transformer T1, a load resistor R1, a resistor R2, a capacitor C3, a diode D1, and a diode D2; The control power supply generates a primary coil current through the series circuit composed of the sampling capacitor C2 and the primary of the current transformer T1. The secondary of the current transformer T1 outputs a secondary coil current related to the control power supply voltage. The secondary coil current then generates a voltage signal through the load resistor R1; The system power supply forms a series voltage division circuit through the diode D1, the diode D2, and the resistor R2. The resistor R2 divides the voltage as a reference voltage source. The capacitor C3 is connected in parallel with the resistor R2. The reference voltage source is connected to one end of the load resistor R1, and a measurable control power supply voltage signal obtained by adding the reference voltage source and the voltage signal is generated at the other end of the load resistor R1.

5. The magnetically controlled AC contactor and its control module according to claim 1, characterized in that The bridge drive circuit consists of four switching transistors, namely switching transistor G1, switching transistor G2, switching transistor G3, and switching transistor G4. The four switching transistors are connected to the excitation coil to form an H-shaped bridge circuit. The two closing pulse control signals respectively control the conduction of switching transistor G2 and switching transistor G4, and the drive power supply conducts through the series circuit of switching transistor G2, the excitation coil, and switching transistor G4, and the excitation coil passes through a forward pulse current. The two opening pulse control signals respectively control the conduction of switching transistor G1 and switching transistor G3, and the drive power supply conducts through the series circuit of switching transistor G1, the excitation coil, and switching transistor G3, and the excitation coil passes through a reverse pulse current.

6. The magnetically controlled AC contactor and its control module according to claim 1, characterized in that The pulse width of the forward pulse current is equal to the minimum time required for the reliable closing of the magnetically controlled AC contactor plus 2 ms; the pulse width of the reverse pulse current is equal to the minimum time required for the reliable opening of the magnetically controlled AC contactor plus 0.5 ms.

7. The magnetically controlled AC contactor and its control module according to claim 1, characterized in that The control logic of the single-chip microcomputer system is as follows: in the opening state of the magnetically controlled AC contactor, when the control power supply voltage is greater than the closing voltage threshold, the single-chip microcomputer system outputs two closing pulse control signals; in the closing state of the magnetically controlled AC contactor, when the control power supply voltage is less than the opening voltage threshold, the single-chip microcomputer system outputs two opening pulse control signals; the closing voltage threshold is equal to 85% of the rated working voltage of the excitation coil in the magnetically controlled AC contactor; the opening voltage threshold is equal to 50% of the rated working voltage of the excitation coil in the magnetically controlled AC contactor.

Images