CN101504898B - Permanent magnet contactor control apparatus having auxiliary contacts - Google Patents

Abstract

The invention discloses a control device for a permanent magnetic contactor provided with auxiliary contacts, which belongs to the technical field of contactor manufacture. The control device consists of a filtering module (1), an over-voltage protection module (2), a rectification module (3), a delay power-off module (4), an under-voltage protection module (5) a power-off signal judge module (6) and an execution module (7) provided with the auxiliary contacts which are connected in series sequentially. Because normally-closed auxiliary contacts are connected in parallel on capacitors connected in series with a coil in the execution module (7) provided with the auxiliary contacts; when in normal attracting, a major loop consists of the coil and the auxiliary contacts; and when switching-in is in place, the auxiliary contacts are opened, and a charging loop charges the capacitors through the coil. The control device can effectively achieve the aim of switching on for the permanent magnetic contactor with larger rated current to further reduce the volume of a disconnecting capacitor so as to achieve the volume miniaturization of the control device.

Description

A control device for a permanent magnetic contactor with an auxiliary contact

technical field

The invention relates to a control device for a permanent magnetic contactor, in particular to a control device for a permanent magnetic contactor with auxiliary contacts, and belongs to the technical field of contactor manufacturing.

Background technique

The permanent magnet contactor has the advantages of energy saving and noise reduction, and has been widely concerned by scientific researchers and contactor manufacturers. The research of permanent magnet contactor mainly focuses on the permanent magnet operating mechanism and control method. According to the difference of the mechanism in the opening operation, the permanent magnet operating mechanism can be divided into two forms: monostable and bistable. From the number of coils, it is divided into single coil type and double coil type. In terms of appearance structure, it is divided into square structure (or double E-shaped or U-shaped structure) and cylindrical structure. From the magnetic circuit, it can be divided into parallel magnetic circuit and series magnetic circuit.

Control methods include:

1. The coil and the capacitor are connected in series. Through the charging of the capacitor by the coil, on the one hand, the magnetomotive force generated by the coil is consistent with the magnetomotive force of the permanent magnet, and the closing operation is completed. The stroke of the contactor with a larger current level is larger. Due to the series connection mode, the current waveform decays exponentially. Therefore, the capacitance value of this scheme should be large to prolong the decay time.

2. The coil is directly supplied with normal voltage or higher voltage. After the closing operation is completed, a small current is supplied to the coil, and the magnetomotive force generated by the coil current and the permanent magnet together maintain the pull-in state. In this scheme, the coil still needs to provide a certain current during the operation of the permanent magnetic contactor.

In addition, it also includes other intelligent control schemes, such as generating PWM pulses to chop the coil voltage to adjust the dynamic characteristics and other control methods.

At present, in the first type of control device composed of a coil and a capacitor in series, for a permanent magnet contactor with a large rated current level, the capacitor is selected to be relatively large, which is not conducive to further popularization and application.

Contents of the invention

Technical problem: The purpose of this invention is to address the shortcomings of the above-mentioned technologies, and provide a control device for permanent magnetic contactors with auxiliary contacts. A normally closed auxiliary contact is connected in parallel with the capacitor in series with the coil. When normally closed, the main The circuit is composed of a coil and an auxiliary contact. When the switch is in place, the auxiliary contact is opened, and the charging circuit charges the capacitor through the coil.

Technical solution: In order to achieve the above object, the present invention adopts the following technical solution:

A control device for a permanent magnet contactor with an auxiliary contact, comprising a filter module, an overvoltage protection module, a rectifier module, a power-delay module, a voltage protection module, a power-off signal judging module, and an execution module with an auxiliary contact composed sequentially in series.

In the control device of the permanent magnet contactor with auxiliary contacts of the present invention, the undervoltage protection module consists of the fifth diode D5, the third capacitor C3, the fourth capacitor C4, the fourth resistor R4, the fifth resistor R5, the eighth The Zener diode D8, the second VMOS transistor Q2 and the tenth diode D10 are composed, wherein the anode of the fifth diode D5 is respectively connected to the positive output terminal of the delay power-off module and the positive input terminal of the power-off signal judgment module , the cathode of the fifth diode D5 is respectively connected to one end of the third capacitor C3 and one end of the fourth resistor R4, the other end of the fourth resistor R4 is connected in series with the fifth resistor R5, and the other end of the third capacitor C3 is respectively connected to the extension The negative output terminal of the power-off module is connected to the anode of the twelfth-level tube D10, and the cathode of the twelfth-level tube D10 is respectively connected to the drain of the second VMOS transistor Q2 and the negative input terminal of the power-off signal judgment module. The five resistors R5, the fourth capacitor C4, and the eighth zener diode D8 are connected in parallel between the gate and the source of the second VMOS transistor Q2.

In the control device of the permanent magnet contactor with auxiliary contacts of the present invention, the power-off signal judging module is composed of the sixth diode D6, the seventh diode D7, the ninth zener diode D9, the sixth resistor R6, the seventh Resistor R7, ninth resistor R9, fifth capacitor C5 and first triode Q1, wherein the anode of the seventh diode D7 is respectively connected to the positive output terminal of the undervoltage module and the anode of the sixth diode D6, The cathode of the sixth diode D6 is connected to the first input end of the execution module with auxiliary contacts; the cathode of the seventh diode D7 is respectively connected to one end of the fifth capacitor C5 and one end of the sixth resistor R6, and the fifth capacitor The other end of C5 is respectively connected to the negative input end of the undervoltage module and one end of the seventh resistor R7, and the other end of the seventh resistor R7 is respectively connected to the other end of the sixth resistor R6 and the base of the first triode Q1, The emitter of the first triode Q1 is connected to the anode of the ninth zener diode D9 and then connected to the fourth input end of the actuator module with an auxiliary contact, and the cathode of the ninth zener diode D9 is respectively connected to one end of the ninth resistor R9 , the collector of the first triode Q1 is connected to the third input end of the module with auxiliary contacts, and the other end of the ninth resistor R9 is connected to the second input end of the module with auxiliary contacts.

In the control device of the permanent magnet contactor with auxiliary contacts of the present invention, the auxiliary contact execution module is composed of the eighth resistor R8, the sixth capacitor C6, the coil J, the eleventh diode D11, the third VMOS transistor Q3 and the auxiliary contact J2, wherein one end of the eighth resistor R8 is respectively connected to the first output end of the power-off signal judging module and one end of the coil J, and the other end of the eighth resistor R8 is respectively connected to the drain of the third VMOS transistor Q3, the first The cathode of the eleventh diode D11 is connected, the gate of the third VMOS transistor Q3 is connected to the third output terminal of the power-off signal judgment module, and the anode of the eleventh diode D11 is connected to the source of the third VMOS transistor Q3 After connecting with the fourth output end of the power-off signal judging module and one end of the sixth capacitor C6, the other end of the sixth capacitor C6 is connected to the second output end of the power-off signal judging module after being connected with the other end of the contactor coil J connection, the auxiliary contact J2 is connected in parallel with the capacitor C6.

Beneficial effects: the invention is designed for the permanent magnet contactor used in low-voltage switchgear, control equipment and motor starting. During the operation of the permanent magnet contactor, the coil will not burn out, the grid voltage will fluctuate, and the contacts will not vibrate. In the undervoltage state, the load is automatically cut off to realize undervoltage protection. The instantaneous power failure of the power grid can be avoided through the delayed power-off function.

The opening and closing process of the permanent magnet contactor with auxiliary contacts of the present invention can effectively achieve the purpose of closing for permanent magnet contactors with relatively large rated currents; the opening and closing method of the auxiliary contacts further reduces the loss of the opening capacitance volume, thereby realizing the miniaturization of the control device volume.

Description of drawings

Fig. 1 is a block diagram of the control device of the present invention.

Among them: filtering module 1, overvoltage protection module 2, rectification module 3, delayed power-off module 4, under-voltage protection module 5, power-off signal judging module 6 and execution module 7 with auxiliary contacts.

Fig. 2 is a schematic diagram of a control circuit suitable for a permanent magnetic contactor.

The above circuit includes external AC power supply, stop button TA, start button QA, permanent magnetic contactor auxiliary contacts J1 and J2, varistor R2, diodes D1~D7, D10, D11, Zener diodes D8~D9, Capacitors C1-C6, resistors R1, R3-R9, triode Q1, VMOS transistors Q2, Q3, contactor coil J.

Detailed ways

As shown in Figure 1, the control device of the permanent magnet contactor with auxiliary contacts of the present invention consists of a filter module 1, an overvoltage protection module 2, a rectifier module 3, a delayed power-off module 4, an undervoltage protection module 5, The power-off signal judging module 6 and the executing module 7 with auxiliary contacts are sequentially connected in series.

As shown in FIG. 2 , the circuit implementation of the control device of the present invention is implemented.

In the control device of the permanent magnet contactor with auxiliary contacts of the present invention, the filter module 1 is composed of a first resistor R1 and a first capacitor C1 connected in series;

In the control device of the permanent magnet contactor with auxiliary contacts of the present invention, the overvoltage protection module 2 is composed of a piezoresistor R2;

In the control device of the permanent magnet contactor with auxiliary contacts of the present invention, the rectifier module 3 consists of the first diode D1, the second diode D2, the third diode D3, and the fourth diode D4. String and make up.

In the control device of the permanent magnetic contactor with auxiliary contacts of the present invention, the delay power-off module 4 is composed of a third resistor R3 connected in series with a second capacitor C2.

In the control device of the permanent magnet contactor with auxiliary contacts of the present invention, the undervoltage protection module 5 is composed of the fifth diode D5, the third capacitor C3, the fourth capacitor C4, the fourth resistor R4, the fifth resistor R5, the Composed of eight voltage-stabilizing diodes D8, the second VMOS transistor Q2 and the tenth diode D10, the anode of the fifth diode D5 is respectively connected to the positive output terminal of the delay power-off module and the positive input terminal of the power-off signal judgment module connected, the cathode of the fifth diode D5 is respectively connected to one end of the third capacitor C3 and one end of the fourth resistor R4, the other end of the fourth resistor R4 is connected in series with the fifth resistor R5, and the other end of the third capacitor C3 is respectively connected to The negative output terminal of the delayed power-off module is connected to the anode of the twelfth-level tube D10, and the cathode of the twelfth-level tube D10 is respectively connected to the drain of the second VMOS tube Q2 and the negative input terminal of the power-off signal judgment module, The fifth resistor R5, the fourth capacitor C4, and the eighth zener diode D8 are connected in parallel between the gate and the source of the second VMOS transistor Q2.

In the control device of the permanent magnet contactor with auxiliary contacts of the present invention, the power-off signal judging module 6 is composed of the sixth diode D6, the seventh diode D7, the ninth zener diode D9, the sixth resistor R6, the first Composed of seven resistors R7, ninth resistor R9, fifth capacitor C5 and first triode Q1, where the anode of the seventh diode D7 is respectively connected to the positive output terminal of the undervoltage module and the anode of the sixth diode D6 , the cathode of the sixth diode D6 is connected to the first input end of the execution module with auxiliary contacts; the cathode of the seventh diode D7 is respectively connected to one end of the fifth capacitor C5 and one end of the sixth resistor R6, and the fifth The other end of the capacitor C5 is respectively connected to the negative input end of the undervoltage module and one end of the seventh resistor R7, and the other end of the seventh resistor R7 is respectively connected to the other end of the sixth resistor R6 and the base of the first transistor Q1 , the emitter of the first triode Q1 is connected to the anode of the ninth zener diode D9 and then connected to the fourth input end of the execution module with an auxiliary contact, and the cathode of the ninth zener diode D9 is respectively connected to the ninth resistor R9 One end is connected to the collector of the first transistor Q1 and the third input end of the module with auxiliary contacts, and the other end of the ninth resistor R9 is connected to the second input end of the module with auxiliary contacts.

In the control device of the permanent magnet contactor with auxiliary contacts of the present invention, the auxiliary contact execution module 7 is composed of an eighth resistor R8, a sixth capacitor C6, a coil J, an eleventh diode D11, a third VMOS transistor Q3 and Auxiliary contact J2, wherein one end of the eighth resistor R8 is respectively connected to the first output end of the power-off signal judging module and one end of the coil J, and the other end of the eighth resistor R8 is respectively connected to the drain of the third VMOS transistor Q3, The cathode of the eleventh diode D11 is connected, the gate of the third VMOS transistor Q3 is connected to the third output terminal of the power-off signal judgment module, and the anode of the eleventh diode D11 is connected to the source of the third VMOS transistor Q3 After connecting, respectively connect with the fourth output end of the power-off signal judging module and one end of the sixth capacitor C6, the other end of the sixth capacitor C6 is connected with the other end of the coil J and then connected with the second output end of the power-off signal judging module , the auxiliary contact J2 is connected in parallel with the capacitor C6.

When the control power supply voltage is in the range of 85% to 110%, press the start button QA, the power supply is firstly filtered by the first resistor R1 and the first capacitor C1 in series, and when the voltage is overvoltage, the varistor R2 protects the circuit . After being rectified by the first diode D1 , the second diode D2 , the third diode D3 and the fourth diode D4 , the current is divided into four paths. The first path passes through the series circuit composed of the third resistor R3 and the second capacitor C2, and the delayed power-off time is adjusted by adjusting the RC parameters; the second path flows through the fifth diode D5, at this time, the second VMOS transistor The drain and source of Q2 are reliably turned on; the third path flows through the seventh diode D7, and the potential on the seventh resistor R7 rises, so that the first transistor Q1 is in a conductive state, and the first transistor Q1 The potential of the collector terminal is pulled down, so that the drain and source of the third VMOS transistor Q3 are in the cut-off state; the last path flows to the contactor coil J through the sixth diode D6 and conducts through the auxiliary contact J2, and the coil and the permanent magnet Under the action of the magnetomotive force generated together, the contactor completes the closing operation. When the closing is in place, the auxiliary contact opens, and the capacitor starts to be charged through the coil J. When opening, only a small current is needed, so the value of the capacitance is smaller. When the power is lost or the power supply voltage is in the range of 20% to 75%, the power-off delay module composed of the third resistor R3 and the second capacitor C2 starts to discharge, keeping the contactor disconnected with a delay at the instant of power shaking. When the power supply voltage falls within the range of 20% to 75%, the second VMOS transistor Q2 is turned off, the first triode Q1 is turned off, the gate voltage of the third VMOS transistor Q3 rises, and the drain-source of the third VMOS transistor Q3 Conduction, the sixth capacitor C6 forms a discharge circuit through the coil J, the eighth resistor R8, and the third VMOS tube Q3, and the contactor coil J generates a magnetomotive force opposite to the permanent magnet steel. Under the reaction force of the spring, the moving iron core It is separated from the static iron core to realize the opening operation of the permanent magnetic contactor.

Claims (3)

1. control device with permanent magnet contactor of auxiliary contact is by filtration module (1), overvoltage protective module (2), rectification module (3), delay cut-off module (4), under-voltage protection module (5), power-off signal judge module (6) with have auxiliary contact Executive Module (7) and be composed in series successively; It is characterized in that: described power-off signal judge module (6) is made up of the 6th diode D6, the 7th diode D7, the 9th voltage stabilizing didoe D9, the 6th resistance R 6, the 7th resistance R 7, the 9th resistance R 9, the 5th capacitor C 5 and the first triode Q1, wherein the anode of the 7th diode D7 is connected with the positive output end of under-voltage protection module (5), the anode of the 6th diode D6 respectively, and the negative electrode of the 6th diode D6 is connected with the first input end with auxiliary contact Executive Module (7); The negative electrode of the 7th diode D7 respectively with an end of the 5th capacitor C 5; one end of the 6th resistance R 6 connects; the other end of the 5th capacitor C 5 respectively with the negative input end of under-voltage protection module (5); one end of the 7th resistance R 7 connects; the other end of the 7th resistance R 7 respectively with the other end of the 6th resistance R 6; the base stage of the first triode Q1 connects; the emitter of the first triode Q1 is connected the back and is connected with the four-input terminal with auxiliary contact Executive Module (7) with the anode of the 9th voltage stabilizing didoe D9; the negative electrode of the 9th voltage stabilizing didoe D9 respectively with an end of the 9th resistance R 9; the collector electrode of the first triode Q1; the 3rd input that has in the auxiliary contact Executive Module (7) connects, and the other end of the 9th resistance R 9 is connected with second input in having auxiliary contact Executive Module (7).

2. the control device with permanent magnet contactor of auxiliary contact according to claim 1; it is characterized in that described under-voltage protection module (5) is by the 5th diode D5; the 3rd capacitor C 3; the 4th capacitor C 4; the 4th resistance R 4; the 5th resistance R 5; the 8th voltage stabilizing didoe D8; the 2nd VMOS pipe Q2 and the tenth diode D10 form; wherein the anode of the 5th diode D5 respectively with the positive output end of delay cut-off module (4); the positive input terminal of power-off signal judge module (6) connects; the negative electrode of the 5th diode D5 respectively with an end of the 3rd capacitor C 3; one end of the 4th resistance R 4 links to each other; the other end of the 4th resistance R 4 and 5 series connection of the 5th resistance R; the other end of the 3rd capacitor C 3 respectively with the negative output terminal of delay cut-off module (4); the anode of the tenth diode D10 connects; the negative electrode of the tenth diode D10 is managed the drain electrode of Q2 respectively with the 2nd VMOS; the negative input end of power-off signal judge module (6) connects, the 5th resistance R 5; the 4th capacitor C 4; the 8th voltage stabilizing didoe D8 is connected in parallel between the grid and source electrode of the 2nd VMOS pipe Q2.

3. according to the control device of the permanent magnet contactor with auxiliary contact of claim 1, it is characterized in that describedly having auxiliary contact Executive Module (7) by the 8th resistance R 8, the 6th capacitor C 6, contactor coil J, the 11 diode D11, the 3rd VMOS pipe Q3 and auxiliary contact J2 form, wherein an end of the 8th resistance R 8 respectively with first output of power-off signal judge module (6), the end of coil J connects, the other end of the 8th resistance R 8 is managed the drain electrode of Q3 respectively with the 3rd VMOS, the negative electrode of the 11 diode D11 connects, the grid of the 3rd VMOS pipe Q3 is connected with the 3rd output of power-off signal judge module (6), after the source electrode of the anode of the 11 diode D11 and the 3rd VMOS pipe Q3 is connected respectively with the 4th output of power-off signal judge module (6), one end of the 6th capacitor C 6 connects, the other end of the 6th capacitor C 6 is connected the back and is connected with second output of power-off signal judge module (6) with the other end of coil J, auxiliary contact J2 is in parallel with the 6th capacitor C 6.

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