WO2023056777A1

WO2023056777A1 - Energy-saving control method for contactor

Info

Publication number: WO2023056777A1
Application number: PCT/CN2022/110370
Authority: WO
Inventors: 宁乐平; 姜勇
Original assignee: 南京全宁电器有限公司
Priority date: 2021-10-08
Filing date: 2022-08-04
Publication date: 2023-04-13
Also published as: CN113611572B; CN113611572A; EP4394835A1

Abstract

Disclosed is an energy-saving control method for a contactor, comprising: connecting a contactor: after controlling a power supply to be connected, an energy storage circuit operates to charge an energy storage capacitor, and a coil of a contactor KM generates an attractive magnetic force after receiving a pulse voltage signal, causing an action mechanism of the contactor KM to act; disconnecting the contactor: when controlling the power supply to disconnect, the energy storage capacitor of the energy storage circuit discharges so as to provide release electric energy for the coil of the contactor KM, the release electric energy passing through a full-bridge driving control circuit to output a pulse having a polarity opposite to that of the coil of the contactor KM, and the coil of the contactor KM generates a reverse magnetic force. In the method of the present invention, a magnetic holding contactor completely replaces a conventional energy-saving control module of a common contactor, and has a common non-magnetic holding contactor, achieving single-wire inching control of connection and disconnection and solving the problem of a magnetic holding contactor not being able to achieve single-wire inching control of connection and disconnection; in addition, power consumption of the contactor coil in the present invention can be reduced by 98%, having a significant energy-saving effect.

Description

A kind of energy-saving control method of contactor

technical field

The invention belongs to the technical field of electromagnetic control circuits, and in particular relates to an energy-saving control method for a contactor.

Background technique

Compared with ordinary contactors, the magnetic holding contactor has the biggest difference in that it is mainly used in dense installation environments or special equipment for high-current on-off control. Its main feature is that the main circuit on-off operation only needs to operate the coil Apply a forward or reverse instantaneous pulse; because the permanent magnet material is used as the closing power of the main circuit, the contact pressure of the main circuit is high, the working voltage is high, the contact resistance is small, energy saving and environmental protection, and it can run under the working condition of super long time operation Reliable and the coil generates almost no energy consumption; while ordinary DC contactors, after the pull-in, the coil is always energized, the long-term work consumes a lot of energy, the coil heats up, and there will even be noise for a long time, which not only wastes electric energy but also causes insulation aging due to the heating of the coil Shortened service life.

However, the magnetic holding contactor needs to switch on and off to control the pulse voltage of the forward or reverse state. Compared with the ordinary contactor, the control circuit is complicated. If it is used in some traditional application fields of machine tool electrical control, the control circuit must be changed. There are two commonly used methods to change the control circuit; 1. Two-input and two-outlet four-wire full-bridge drive and logic interlock require 4 transistors and logic electronic circuits. In this method, the number of control connections and control components for magnetic retention is the same as The single-point control of ordinary contactors requires only one control line to control on-off, which is extraordinarily complicated; 2. Three-wire push-pull drive and logic interlock require two coils and logic electronic circuits, and magnetically latched contactors If it is used in general power control circuits, such as forward and reverse switching of machine tool spindle motors, start and stop hold, jog control, etc., the cost of changing the control circuit will increase geometrically, which is several times higher than that of ordinary contactors. Even dozens of times, the reliability, economy, and work efficiency will be greatly reduced. In addition, in some occasions that require multi-point interlocking and high safety requirements, it cannot be used at all. At the same time, the control circuit changes are complicated and the reliability is poor. The biggest problem It cannot solve the problem that the power failure cannot be disconnected, the safety cannot be guaranteed, and it cannot be applied to the general logic control power circuit. Therefore, it is necessary to develop a new control method to solve the existing problems.

Contents of the invention

The object of the present invention is to provide an energy-saving control method for a contactor that does not need to change the original contactor controller circuit to achieve high efficiency and energy saving, so that the magnetic holding contactor can completely replace the energy-saving control module of the traditional ordinary contactor, and has the common non- The magnetic latching contactor realizes the single-line jog control opening and closing to solve the problem that the magnetic latching contactor cannot be single-line jogging control opening and closing.

In order to achieve the above object, the present invention provides the following technical solutions: an energy-saving control method for a contactor, comprising: an energy-saving control method for a contactor, comprising:

The contactor is turned on: After the control power is turned on, the energy storage circuit works to charge the energy storage capacitor, and at the same time, the coil of the contactor KM generates an attractive magnetic force after receiving the pulse voltage signal, so that the action mechanism of the contactor KM operates, and the contactor KM The main circuit contact of KM is connected, the coil control circuit of the contactor KM loses power within the set millisecond delay time, and the contactor KM continues to keep the main circuit contact of the contactor KM under the action of the permanent magnet. pass status;

Contactor disconnection: When the control power supply is disconnected, the energy storage capacitor of the energy storage circuit discharges to provide released electric energy for the coil of the contactor KM, and the released electric energy passes through the full-bridge drive control circuit to output a coil absorbing with the contactor KM When the pulse with the opposite voltage polarity is applied, the coil of the contactor KM generates a reverse magnetic force, and the direction of the magnetic field is reversed, so that the action mechanism of the contactor KM moves in the opposite direction of the pull-in, and the main circuit contact of the contactor KM is broken. Open, after the coil of the contactor KM loses power, the contactor KM will keep the main circuit contact of the contactor KM disconnected under the action of releasing the permanent magnet.

The above-mentioned energy-saving control method also includes an energy-saving control circuit, and the energy-saving control circuit includes a full-bridge driver chip U1 for controlling the function of the contactor KM, an energy storage circuit connected to the control power supply, connected with the energy storage circuit and stabilizing the input voltage. After the voltage is sent to the voltage stabilizing circuit of the full-bridge driver chip U1, the voltage signal detection and adjustment circuit, the three-stage inverter connected to the voltage signal detection and adjustment circuit, and the circuit for generating the pull-in voltage and the contactor KM turn-on delay Pull-in delay adjustment circuit, release delay adjustment circuit for controlling the release voltage and contactor KM disconnection delay; the pull-in delay adjustment circuit and release delay adjustment circuit are both connected to the three-stage inverter ; The voltage signal detection and adjustment circuit is connected to the control power supply for input voltage signal detection and adjustment and filter overvoltage protection;

The full-bridge drive control circuit is built in the full-bridge drive chip U1;

The three-stage inverter includes an inverter U2A, an inverter U2B, and an inverter U2C connected in series.

When the above-mentioned control power supply is turned on, the energy storage circuit charges the energy storage capacitor C1, and at the same time, the coil of the contactor KM generates an attractive magnetic force after receiving the pulse voltage signal, so that the action mechanism of the contactor KM generates an attractive magnetic force on the coil of the contactor KM It is turned on under the combined action of the attraction magnetic force of the pull-in permanent magnet, and a signal is sent to the full-bridge drive chip U1 through the pull-in delay adjustment circuit. When the full-bridge drive chip U1 receives the signal, it controls to turn off the contactor KM The coil voltage of the contactor KM is de-energized, and the main circuit contact of the contactor KM remains on under the action of the permanent magnet;

When the control power supply is disconnected, the full-bridge drive chip U1 receives the power-off signal from the voltage signal detection and adjustment circuit, converts the polarity of the energy and voltage of the energy storage capacitor C1 in the energy storage circuit, and sends it to the contactor The coil of KM, the coil of the contactor KM produces a magnetic force opposite to the existing magnetic force, the reverse magnetic force makes the contactor KM break away from the attractive magnetic force of the permanent magnet, and the action mechanism of the contactor KM is related to the release of the permanent magnet. Fitting, the main circuit contact of the contactor KM is disconnected, and then the release delay adjustment circuit sends a signal to the full-bridge driver chip U1 to de-energize the coil of the contactor KM, and the main circuit contact of the contactor KM is released permanently The disconnected state is maintained under the action of the magnet.

The pull-in delay adjustment circuit includes a transistor V1 connected to the output terminal of the inverter U2B, and a capacitor C2 connected to the transistor V1; the output terminal of the inverter U2B is divided in series with the resistor R2 and the resistor R3 to divide the voltage The bases of the triode V1 are connected, and the collector of the triode V1 is connected to the IN2 pin of the full-bridge driver chip U1 through a resistor R6;

When the charging voltage of the capacitor C2 reaches the conduction threshold of the triode V1, the IN2 pin level of the full-bridge driver chip U1 is pulled down, and the OUT1 pin and OUT2 pin of the full-bridge driver chip U1 output High resistance, the coil of the contactor KM loses power; the input terminal of the inverter U2B is connected to the output terminal of the inverter U2A, and the input terminal of the inverter U2A is connected to the control power supply through the resistor R4 and the resistor R5 Positive pole, the two ends of the resistor R5 are connected in parallel with a capacitor C3 and a Zener diode DW1.

The above-mentioned release delay adjustment circuit includes a transistor V2 connected to the output terminal of the inverter U2C, and a capacitor C4 connected to the transistor V2; the output terminal of the inverter U2C is divided in series with the resistor R10 through the resistor R10 and then connected to the transistor V2. The base of the transistor V2 is connected to the base, the collector of the triode V2 is connected to the IN1 pin of the full-bridge driver chip U1, and the collector of the transistor V2 is also connected to the output terminal of the inverter U2C through a resistor R9;

When the charging voltage of the capacitor C4 reaches the conduction threshold of the triode V2, the IN1 pin level of the full-bridge driver chip U1 is pulled down, and the OUT1 pin and the OUT2 pin of the full-bridge driver chip U1 output high impedance , the coil of the contactor KM loses power.

The anode of the control power supply is also connected to the diode D1, and the diode D1 is also connected to the VBB pin of the full-bridge driver chip U1;

When the control power supply is powered off, the diode D1 is turned off in reverse, and the output terminal of the inverter U2C outputs a high-level signal to the full-bridge driver chip U1, and the full-bridge driver chip U1 converts the polarity of the power supply output.

When the control power supply is turned on, the current generated by the control power supply is also connected to the Vref pin of the full-bridge driver chip U1 through a circuit in which the resistor R1 and the Zener diode DW2 are connected in series.

The energy storage capacitor C1 is connected to the control power supply through the buffer resistor R8.

The above-mentioned resistor R8 is connected to the LSS pin of the full-bridge driver chip U1 through a resistor R7, and a freewheeling diode is arranged between the resistor R7 and the resistor R8, and the freewheeling diode includes a diode D3, a diode D5, a diode D2 and a diode D4 , the diode D2 and the diode D4 are connected in parallel with the diode D3 and the diode D5.

The technical effects and advantages of the present invention: the energy-saving control method of the contactor is easy to install, simple to connect, low in cost, and has obvious energy-saving effect, so that the magnetic holding contactor can completely replace the energy-saving control module of the traditional common contactor, and the control module can be used The magnetic latching contactor can have the characteristics of ordinary non-magnetic latching contactors, realize single-line inching control opening and closing, and at the same time retain all the advantages of the magnetic latching contactor. The invention meets the national requirements for energy saving, emission reduction, and environmental protection. The details are as follows advantage:

1. After receiving the power-off signal of the voltage signal detection and adjustment circuit through the full-bridge driver chip U1, the electrode of the input voltage of the energy storage circuit is converted and sent to the coil of the contactor KM, and the coil of the contactor KM A magnetic force opposite to the existing magnetic force is generated to disconnect the contactor, the coil of the contactor KM loses power, and the coil current is zero. In this state, the contactor is kept in the pull-in state by the permanent magnet, and the coil current of the contactor KM is zero. At this time, the coil of the contactor KM has zero power consumption. The energy consumption and so on add up to about 0.2W, and the maintenance power of the general contactor is about 10W-30W. Compared with the power consumption of 0.2W, the coil control circuit of the contactor KM is in a state of micro power consumption;

2. Send a power-off signal to the full-bridge drive chip U1 through the pull-in delay adjustment circuit, the coil of the contactor KM connected to the full-bridge drive chip U1 loses power, and the release delay adjustment circuit sends a power-off signal The signal is sent to the full-bridge driver chip U1 to de-energize the coil of the contactor KM, and the contactor remains disconnected under the action of the permanent magnet, so that the coil of the contactor KM does not need to be energized for a long time when the contactor controls the main circuit contact. , it only needs an instantaneous pulse voltage to do it, and then it is always kept on by the magnetic force of the permanent magnet. To achieve this for ordinary contactors, the coil of the contactor KM needs to be powered off all the time; the coil of the contactor KM of the present invention is powered off after a delay of 10mS, and the contactor KM is controlled in two states of power on and power off. The coil obtains two voltage pulse signals with opposite polarities, so that the magnetic latching contactor and the non-magnetic latching contactor have the same pull-in characteristics, and at the same time have the purpose of high efficiency and energy saving;

3. Adjust the resistance ratio of resistor R2 and resistor R3 to adjust the release characteristics during the slow drop of the power supply voltage, and adjust the pull-in characteristics during the slow rise of the power supply voltage by adjusting the resistance ratio of resistor R4 and resistor R5 ;

4. The input terminal of U2A is connected to the positive pole of the control power supply through resistor R4 and resistor R5. The two ends of the resistor R5 are connected in parallel with a capacitor C3 and a Zener diode DW1. The Zener diode DW1 prevents power from being damaged during power up or debugging. inverter;

5. The resistor R8 is connected to the LSS pin of the full-bridge drive chip U1 through the resistor R7, a diode D3 and a diode D5 are arranged between the resistor R7 and the resistor R8, and the diode D3 and the diode D5 are connected to the diode D2 and the diode D5. The diode D4 is connected in series, the diode D2, the diode D3, the diode D4, and the diode D5 can absorb the reverse electromotive force generated when the coil of the contactor KM works, and the resistor R7 is the current limiting protection sampling resistor.

Description of drawings

Fig. 1 is a circuit diagram of the present invention;

Fig. 2 is the circuit diagram that the access power of the present invention is AC and DC;

Fig. 3 is the circuit diagram that the access power of the present invention is AC high voltage;

Fig. 4 is a functional frame diagram of the full-bridge driver chip U1 of the present invention;

FIG. 5 is a pin distribution diagram of the full-bridge driver chip U1 of the present invention;

Fig. 6 is the front view of the contactor of the present invention;

Fig. 7 is a cross-sectional view of the contactor of the present invention along the direction D.

In the figure: 1. Main circuit contact; 2. Action mechanism; 3. Release permanent magnet; 4. Coil; 5. Pull-in permanent magnet; 6. Release delay adjustment circuit.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

The present invention provides an energy-saving control method for a contactor as shown in Figures 1-7, including:

Steps to turn on the contactor: as shown in Figure 1, Figure 6, and Figure 7, after the control power is turned on, the energy storage circuit is charged, and at the same time, the coil 4 of the contactor KM generates an attractive magnetic force after receiving the pulse voltage signal, so that the contactor The action mechanism 2 of KM operates, the main circuit contact 1 of the contactor KM is connected, and the control circuit of the contactor KM coil is disconnected within milliseconds of the delay setting. In this embodiment, the set disconnection time is 10mS, and the contact The device KM continues to keep the main circuit contact 1 of the contactor KM on under the action of the pull-in permanent magnet 5; in the step of connecting the contactor in this embodiment, the pull-in delay adjustment circuit includes a connection with the inverter U2B The transistor V1 connected to the output terminal, the capacitor C2 connected to the transistor V1, the output terminal of the inverter U2B is connected to the base of the transistor V1 after being divided in series by the resistor R2 and the resistor R3, and the collector of the transistor V1 Connect to the IN2 pin of the full-bridge driver chip U1 through the resistor R6; when the charging voltage of the capacitor C2 reaches the conduction threshold of the transistor V1, the level of the IN2 pin of the full-bridge driver chip U1 is pulled down, so The OUT1 pin and OUT2 pin of the full-bridge driver chip U1 output high resistance, the coil 4 of the contactor KM loses power, the input end of the inverter U2B is connected with the output end of the inverter U2A, and the U2A The input terminal of the control power supply is connected to the positive pole of the control power supply through the resistor R4 and the resistor R5, and the two ends of the resistor R5 are connected in parallel with a capacitor C3 and a Zener diode DW1;

When the control power supply is turned on, the current is also sent to the energy storage circuit; the energy storage circuit includes an energy storage capacitor C1 for storing electric energy, and the energy storage capacitor C1 is connected to the control power supply through a buffer resistor R8. Charging the energy storage capacitor C1;

When the control power supply is turned on, the current is also connected to the Vref pin of the analog voltage input of the full-bridge driver chip U1 through the circuit connected in series with the resistor R1 and the Zener diode DW2, and the resistor R8 is connected to the Vref pin of the full-bridge driver chip U1 through the resistor R7. On the LSS pin, a freewheeling diode is arranged between the resistor R7 and the resistor R8, and the freewheeling diode includes a diode D3 and a diode D5, and a diode D2 and a diode D4 connected in parallel with the diode D3 and the diode D5;

The step of disconnecting the contactor: when the control power supply is disconnected, the energy storage circuit discharges to provide released electric energy for the coil 4 of the contactor KM, and the released electric energy passes through the full-bridge drive control circuit to output a coil 4 of the contactor KM to absorb Combined with the pulse with the opposite voltage polarity, the full-bridge driver chip U1 receives the power-off signal from the voltage signal detection and adjustment circuit, and then sends the power supply polarity of the input voltage of the energy storage circuit to the coil 4. In this embodiment, the full-bridge The drive chip U1 turns out a reverse pulse voltage signal, and the coil 4 of the contactor KM generates a magnetic force opposite to the existing magnetic force to disconnect the main circuit contact 1 of the contactor KM. In this embodiment, the contactor KM is in the coil Under the action of the reverse magnetic force generated by 4, the magnetic direction of the magnetic field is reversed, and the action mechanism 2 of the contactor KM moves in the opposite direction of the pull-in, so that the main circuit contact 1 of the contactor KM is disconnected, and the coil of the contactor KM 4 After power failure, the main circuit contact 1 of the contactor KM remains disconnected under the action of the release permanent magnet 3;

The energy-saving control method also includes an energy-saving control circuit, the energy-saving control circuit includes a full-bridge driver chip U1 for controlling the function of the contactor KM, an energy storage circuit connected to the control power supply, connected to the energy storage circuit and input voltage After the voltage is stabilized, it is sent to the voltage stabilization circuit of the full-bridge driver chip U1, the voltage signal detection and adjustment circuit connected to the control power supply for input voltage signal detection and adjustment and filter overvoltage protection, and the three-phase circuit connected to the voltage signal detection and adjustment circuit. Stage inverter, pull-in delay adjustment circuit for generating pull-in voltage and contactor KM turn-on delay, release delay adjustment circuit 6 for controlling release voltage and contactor KM turn-off delay; Both the pull-in delay adjustment circuit and the release delay adjustment circuit 6 are connected to the three-stage inverter;

A full-bridge drive control circuit is set in the full-bridge drive chip U1;

The three-stage inverter includes a serial inverter U2A, an inverter U2B, and an inverter U2C;

In the step of connecting the contactor, when the control power is turned on, the energy storage circuit charges the energy storage capacitor C1, and at the same time, the coil 4 of the contactor KM generates an attractive magnetic force after receiving the pulse voltage signal, so that the operating mechanism 2 of the contactor KM The contactor KM is turned on under the combined action of the attractive magnetic force generated by the coil 4 of the contactor KM and the attractive magnetic force of the permanent magnet 5, and sends a signal to the full-bridge driver chip U1 through the pull-in delay adjustment circuit, when the full-bridge driver chip U1 receives After the contactor KM turns on the signal, the full-bridge drive chip U1 turns off the voltage of the coil 4 of the contactor KM, the coil 4 of the contactor KM loses power, and the main circuit contact 1 of the contactor KM acts on the permanent magnet 5 stay connected;

In the step of disconnecting the contactor, when the control power supply is disconnected, the full-bridge drive chip U1 receives the power-off signal from the voltage signal detection and adjustment circuit, and then converts the polarity of the energy voltage in the energy storage circuit and sends it to the The coil 4 of the contactor KM, the coil 4 of the contactor KM produces a magnetic force opposite to the existing magnetic force, that is, the reverse magnetic force makes the contactor KM break away from the attractive magnetic force of the permanent magnet 5, and the action of the contactor KM The mechanism 2 is attracted to the release permanent magnet 3, the main circuit contact 1 of the contactor KM is disconnected, and then the release delay circuit sends a power-off signal to the full-bridge driver chip U1 to de-energize the coil 4 of the contactor KM, and the contact The main circuit contact 1 of the device KM remains disconnected under the action of the release permanent magnet 3 .

In the step of disconnecting the contactor, the release delay circuit includes a transistor V2 connected to the output terminal of the inverter U2C, a capacitor C4 connected to the transistor V2, and the output terminal of the inverter U2C is connected to the output terminal of the inverter U2C through a resistor R10. The resistor R11 is connected in series with the base of the triode V2 after voltage division, the collector of the triode V2 is connected to the IN1 pin of the full-bridge driver chip U1, and the collector of the triode V2 is also connected to the inverting phase through the resistor R9. connected to the U2C output of the device;

When the charging voltage of the capacitor C4 reaches the conduction threshold of the triode V2, the IN1 pin level of the full-bridge driver chip U1 is pulled down, and the OUT1 pin and the OUT2 pin of the full-bridge driver chip U1 output high impedance , the coil 4 of the contactor KM loses power.

The anode of the control power supply is also connected to the diode D1, and the diode D1 is also connected to the VBB pin of the full bridge driver chip U1; it is the working voltage of the coil 4 of the contactor KM;

When the control power supply is cut off, the diode D1 is reversely cut off, and the output terminal of the inverter U2C outputs a high-level signal to the full-bridge driver chip U1, and the full-bridge driver chip U1 converts the electrode and outputs it.

The energy-saving control method of the contactor, as shown in Figure 1, controls the power supply to be powered on, and the anode voltage provides the power supply voltage for the VBB pin of the full-bridge driver chip U1 through the diode D1, that is, the working voltage of the coil 4 of the contactor KM. The buffer resistor R8 charges the energy storage capacitor C1; through the voltage division of the resistor R1 and the voltage regulator diode DW2, a regulated voltage of 5V is connected to the analog voltage input Vref pin of U1; the positive pole of the control power supply is divided by the resistor R4 and the resistor R5 Afterwards, it is connected to the input terminal of the inverter U2A of the three-stage inverter composed of the inverter U2A, the inverter U2B, and the inverter U2C connected in series; the output terminal of the inverter U2B obtains a level signal synchronous with the input, The output terminal of U2C obtains the level signal inverted from the input terminal of the inverter U2A, and is connected with the IN1 pin of the full-bridge driver chip U1, and connected with the IN2 pin of the full-bridge driver chip U1 through the resistor R6; according to the full-bridge The truth table of the driver chip U1, see Table 1,

Table 1

The OUT1 pin of the full-bridge driver chip U1 outputs the positive pole, the OUT2 pin of the full-bridge driver chip U1 outputs the power supply voltage of the negative pole, the coil 4 of the contactor KM is energized, and the contactor KM is kept closed under the action of the permanent magnet; and the control When the power supply is powered on, the output terminal of the inverter U2B is connected in series with the resistors R2 and R3 to divide the voltage and then connected to the base of the transistor V1 to charge the capacitor C2; when the charging voltage reaches the conduction threshold of the transistor V1, in this embodiment , the arrival of the threshold depends on the charging time of C2, the IN2 pin level of the full-bridge driver chip U1 is pulled down, according to the truth table of the full-bridge driver chip U1, the OUT1 pin and OUT2 pin of the full-bridge driver chip U1 The pin outputs high resistance, the coil 4 of the contactor KM loses power, and the current of the coil 4 is zero. In this state, the contactor is always kept in the state of attraction by the magnetic force of the permanent magnet, and the current of the coil 4 of the contactor KM is zero. At this time, the coil 4 is zero power consumption; in this state, the energy consumption of the voltage dividing resistor, voltage regulator tube, and chip in the circuit in this state is about 0.2W. The maintenance power of the general contactor is about 10W-30W. Compared with the power consumption of 0.2W It can be said that the coil 4 of the contactor KM is basically in a state of micro power consumption;

When the control power supply is powered off, the energy storage capacitor C1 discharges through the diode D10 to continue to provide power for the full-bridge driver chip U1. Because the diode D1 reverses and cuts off, the output terminal of the inverter U2C appears high. According to the truth table, the full The output of the OUT1 pin and OUT2 pin of the bridge driver chip U1 flips instantly, the OUT1 pin outputs the negative pole, and the OUT2 pin outputs the positive pole. The coil 4 of the contactor KM is energized under the action of the energy storage capacitor C1, and the magnetic force generated by the coil The direction state is reversed, and the main circuit contact 1 of the contactor KM remains disconnected under the action of releasing the permanent magnet. The output terminal of the inverter U2C is connected to the base of the triode V2 after being divided in series with the resistors R10 and R11, and at the same time , to charge the capacitor C4, when the charging voltage reaches the conduction threshold of the triode V2, in this embodiment, the arrival of the threshold depends on the charging time of C4, and the IN1 pin level of the full-bridge driver chip U1 is pulled down, according to The truth table of the full-bridge driver chip U1, the OUT1 and OUT2 pins of the full-bridge driver chip U1 output high resistance, the coil 4 of the contactor KM loses power, and the current of the coil 4 is zero instantly. The function of this circuit is to make the coil 4 Delayed release after energization, and then quickly enter the zero current state to prevent the coil 4 of the contactor KM from being energized under low voltage;

In this embodiment, during the entire working process of the circuit, it is set that the coil 4 of the contactor KM is energized and then de-energized after a delay of 10 mS, and the coil 4 of the contactor KM obtains two poles when the power supply is turned on and off. The opposite voltage pulse signal, so as to achieve the same pull-in characteristics of the magnetic latching contactor and the non-magnetic latching contactor, and at the same time have the purpose of high efficiency and energy saving;

In this embodiment, adjusting the resistance ratio of resistor R2 and resistor R3 can adjust the release characteristic during the slow drop of the power supply voltage, that is, the release voltage value; adjusting the resistance ratio of resistor R4 and resistor R5 can adjust the slow rise of the power supply voltage The pull-in characteristic in the process, that is, the pull-in voltage value, the Zener diode DW1 prevents the inverter from being damaged when the power is raised or debugged, and the diode D2, diode D3, diode D4, and diode D5 can absorb the coil 4 of the contactor KM when it is working The reverse electromotive force generated, the resistor R7 is the current limiting protection sampling resistor;

In order to simplify the circuit, reduce the size, and reduce the cost, the full-bridge driver chip U1 using the full-bridge driver chip in the circuit is shown in Figure 4 and Figure 5. As shown, an AC-DC conversion circuit is set at the input end of the control power supply;

When the access control power supply is AC high voltage, as shown in Figure 3, a transformer is installed at the input end of the AC-DC conversion circuit.

Finally, it should be noted that: the above is only a preferred embodiment of the present invention, and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, it still The technical solutions recorded in the foregoing embodiments may be modified, or some of the technical features may be replaced equivalently, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the within the protection scope of the present invention.

Claims

An energy-saving control method for a contactor, characterized in that it includes:

The contactor is turned on: After the control power is turned on, the energy storage circuit works to charge the energy storage capacitor, and at the same time, the coil (4) of the contactor KM generates an attractive magnetic force after receiving the pulse voltage signal, so that the action mechanism (2) of the contactor KM Action, the main circuit contact (1) of the contactor KM is connected, the coil (4) control circuit of the contactor KM loses power within the set millisecond delay time, and the contactor KM is pulling in the permanent magnet ( 5) Continue to keep the main circuit contact (1) of the contactor KM connected under the action;

Contactor disconnection: when the control power supply is disconnected, the energy storage capacitor of the energy storage circuit discharges to provide released electric energy for the coil (4) of the contactor KM, and the released electric energy passes through the full-bridge drive control circuit to output a contactor KM The coil (4) of the contactor KM pulls in the pulse with the opposite polarity of the voltage, the coil (4) of the contactor KM generates a reverse magnetic force, and the direction of the magnetic field is reversed, so that the action mechanism (2) of the contactor KM is opposite to that of the pull-in Direction action, the main circuit contact (1) of the contactor KM is disconnected, and after the coil (4) of the contactor KM loses power, the contactor KM makes the main circuit of the contactor KM contact Head (1) remains disconnected.
An energy-saving control method for a contactor according to claim 1, characterized in that: the energy-saving control method further includes an energy-saving control circuit, and the energy-saving control circuit includes a full-bridge driver chip U1 for controlling the KM function of the contactor , an energy storage circuit connected to the control power supply, a voltage stabilizing circuit connected to the energy storage circuit and sending the input voltage to the full-bridge drive chip U1 after being regulated, a voltage signal detection and adjustment circuit, and a voltage signal detection and adjustment circuit connected to the Three-stage inverter, pull-in delay adjustment circuit for generating pull-in voltage and contactor KM turn-on delay, release delay adjustment circuit for controlling release voltage and contactor KM turn-off delay (6) The pull-in delay adjustment circuit and the release delay adjustment circuit (6) are connected with the three-stage inverter; the voltage signal detection adjustment circuit is connected with the control power supply for input voltage signal detection adjustment and filtering pressure protection;

The full-bridge drive control circuit is built in the full-bridge drive chip U1;

The three-stage inverter includes an inverter U2A, an inverter U2B, and an inverter U2C connected in series.
An energy-saving control method for a contactor according to claim 2, characterized in that: when the control power is turned on, the energy storage circuit charges the energy storage capacitor C1, and at the same time the coil (4) of the contactor KM receives pulses After the voltage signal, an attractive magnetic force is generated, so that the action mechanism (2) of the contactor KM is connected under the combined action of the attractive magnetic force generated by the coil (4) of the contactor KM and the attractive magnetic force of the attracting permanent magnet (5). The closing delay adjustment circuit sends a signal to the full-bridge driver chip U1, and when the full-bridge driver chip U1 receives the signal, it controls to turn off the voltage of the coil (4) of the contactor KM, and the coil (4) of the contactor KM loses power , the main circuit contact (1) of the contactor KM remains connected under the action of the attracting permanent magnet (5);

When the control power supply is disconnected, the full-bridge drive chip U1 receives the power-off signal from the voltage signal detection and adjustment circuit, converts the polarity of the energy and voltage of the energy storage capacitor C1 in the energy storage circuit, and sends it to the contactor The coil (4) of KM, the coil (4) of the contactor KM produces a magnetic force opposite to the existing magnetic force direction, and the reverse magnetic force makes the contactor KM break away from the attractive magnetic force of the permanent magnet (5) and contact The action mechanism (2) of the contactor KM is attached to the release permanent magnet (3), the main circuit contact (1) of the contactor KM is disconnected, and then the release delay adjustment circuit (6) sends a signal to the full bridge driver chip U1 de-energizes the coil (4) of the contactor KM, and the main circuit contact (1) of the contactor KM remains disconnected under the action of releasing the permanent magnet (3).
An energy-saving control method for a contactor according to claim 3, wherein the pull-in delay adjustment circuit includes a transistor V1 connected to the output terminal of the inverter U2B, and a capacitor C2 connected to the transistor V1 The output terminal of the inverter U2B is connected to the base of the triode V1 after being divided in series by the resistor R2 and the resistor R3, and the collector of the triode V1 is connected to the IN2 pin of the full-bridge driver chip U1 through the resistor R6 ;

When the charging voltage of the capacitor C2 reaches the conduction threshold of the triode V1, the IN2 pin level of the full-bridge driver chip U1 is pulled down, and the OUT1 pin and OUT2 pin of the full-bridge driver chip U1 output High resistance, the coil (4) of the contactor KM loses power; the input terminal of the inverter U2B is connected with the output terminal of the inverter U2A, and the input terminal of the inverter U2A is connected with the resistor R5 through the resistor R4 To the positive pole of the control power supply, a capacitor C3 and a Zener diode DW1 are connected in parallel at both ends of the resistor R5.
An energy-saving control method for a contactor according to claim 3, characterized in that: the release delay adjustment circuit (6) includes a transistor V2 connected to the output end of the inverter U2C, a transistor V2 connected to Capacitor C4; the output terminal of the inverter U2C is connected to the base of the transistor V2 after being divided in series with the resistor R10 and the resistor R11, and the collector of the transistor V2 is connected to the IN1 pin of the full-bridge driver chip U1, And the collector of the triode V2 is also connected to the output terminal of the inverter U2C through the resistor R9;

When the charging voltage of the capacitor C4 reaches the conduction threshold of the triode V2, the IN1 pin level of the full-bridge driver chip U1 is pulled down, and the OUT1 pin and the OUT2 pin of the full-bridge driver chip U1 output high impedance , the coil (4) of the contactor KM loses power.
An energy-saving control method for a contactor according to claim 3, wherein the anode of the control power supply is also connected to a diode D1, and the diode D1 is also connected to the VBB pin of the full-bridge driver chip U1;

When the control power supply is powered off, the diode D1 is turned off in reverse, and the output terminal of the inverter U2C outputs a high-level signal to the full-bridge driver chip U1, and the full-bridge driver chip U1 converts the polarity of the power supply output.
An energy-saving control method for a contactor according to any one of claims 3 to 6, characterized in that: when the control power supply is turned on, the current generated by the control power supply is also connected in series through the resistor R1 and the Zener diode DW2 The final circuit is connected to the Vref pin of the full-bridge driver chip U1.
An energy-saving control method for a contactor according to any one of claims 3 to 6, wherein the energy storage capacitor C1 is connected to the control power supply through a buffer resistor R8.
The energy-saving control method of a contactor according to claim 8, characterized in that: the resistor R8 is connected to the LSS pin of the full-bridge driver chip U1 through a resistor R7, and the resistor R7 and the resistor R8 are provided with A freewheeling diode, the freewheeling diode includes a diode D3, a diode D5, a diode D2 and a diode D4, and the diode D2 and the diode D4 are connected in parallel with the diode D3 and the diode D5.