CN220440372U - Control circuit capable of automatically breaking breaker after external power supply is powered off - Google Patents

Abstract

The utility model discloses a control circuit capable of automatically breaking a breaker after an external power supply is powered off, which belongs to the field of control operation of high-voltage motors and solves the problems that in the prior art, when the external power supply fails and has power failure, a breaking tripping electromagnet is not driven by the power supply and cannot execute breaking action, and a closing breaker still keeps a conducting state in a circuit due to the action of a spring. The device mainly comprises a normally closed contact SB1, a current limiting resistor R, a rectifier diode D, a capacitor C and an intermediate relay KA1. The utility model can instantly release electric energy to act on the opening tripping electromagnet when the external electric network fails and the power supply is lost, and reliably break the moving and static contacts, thereby breaking the running circuit of the high-voltage motor.

Description

Control circuit capable of automatically breaking breaker after external power supply is powered off

Technical Field

The utility model relates to a motor control circuit, in particular to a control circuit capable of automatically breaking a circuit breaker after an external power supply is powered off.

Background

The existing power grid supplies power to enterprises, and one three-phase alternating-current high-voltage power supply is adopted to the factory. Along with the increase of the application of the high-voltage motor, the high-voltage motor is widely distributed on an enterprise production line along with the requirements of process equipment, a motor control system is mostly installed near the process line, and a control power supply is mostly an alternating current power supply. The actuating element for the energizing operation of the low-voltage motor is a contactor, a coil of the contactor is energized, an electromagnet is attracted to drive a moving contact to move to a closing position towards a fixed contact, when the coil of the contactor is deenergized, electromagnetic force disappears, and a separating spring drives the moving contact to separate the fixed contact from reset, so that the on-off of a circuit is realized. The switching-on and switching-off process of the circuit breaker comprises the following steps: firstly, the spring is compressed and stored by the energy storage mechanism. When the switch is needed, the switch-on coil is electrified, the switch-on electromagnet acts to enable the energy storage maintaining shaft to rotate, the detent is driven to loosen the roller, the energy storage maintaining is released, the switch-on spring releases energy, and the contact pressure needed by the contact is maintained. After the closing operation is completed, once the opening button signal is received, the opening tripping electromagnet operates, so that the constraint of the holding pawl is released. The energy stored by the over-travel spring and the brake separating spring separates the movable contact from the fixed contact to realize brake separating operation.

Although the circuit breaker control circuit with the publication number of CN106602499A in the prior art effectively improves the reliability of the circuit breaker control circuit and the anti-interference capability of the circuit; the adaptability of the circuit breaker control circuit is effectively improved, the cooperation of the circuit breaker control circuit and the circuit breaker is simplified, the production debugging and engineering implementation are facilitated, but the external power grid fails, the power supply is lost, the opening tripping electromagnet is not driven by the power supply, the opening action cannot be executed, the vacuum circuit breaker which is closed still keeps a conducting state on the circuit due to the action of the spring, and the state can only be manually operated to execute the opening work of the circuit breaker on site. Before the manual work fails to go to the site to execute the breaking work of the breaker, when the external power supply is restored to be delivered, the high-voltage motor can automatically start to operate, so that great potential safety hazards can be caused to operators and equipment.

At present, an operation circuit capable of instantaneously releasing electric energy to disconnect a high-voltage motor when an external electric network fails and a power supply is lost is lacking. Meanwhile, the patent circuit is also provided with detection under a normal working state, so that the integrity of the function of instantaneously releasing the electric energy is maintained. The potential safety hazard of operators and equipment in the production process is solved.

Disclosure of Invention

The utility model aims to provide a control circuit capable of automatically breaking a circuit breaker after an external power supply is powered off, so as to solve the problems that in the prior art, when the external power supply fails and power is cut off, a brake-separating tripping electromagnet is not driven by the power supply, brake-separating action cannot be executed, and the circuit breaker still keeps a conducting state due to the action of a spring.

The utility model is realized by the following technical scheme:

the control circuit comprises a primary loop, wherein the primary loop is connected with a voltage measurement loop through a transformer TV, the voltage measurement loop comprises a voltmeter PV, an intermediate relay KA1 and an input end of a motor integrated protector WB, an output end of the motor integrated protector WB is arranged in an original brake separating circuit, the original brake separating circuit is electrically connected between controlled power supplies, and a brake closing circuit is arranged between the controlled power supplies; the primary opening circuit further comprises a normally open contact QF1 of the circuit breaker, the output end of the motor integrated protector WB is electrically connected with the normally open contact QF1, the normally open contact QF1 is electrically connected with an opening coil TQ of the circuit breaker, a secondary energy storage circuit is arranged between the controlled power supplies and comprises a normally closed contact SB1, the normally closed contact SB1 is electrically connected with a current-limiting resistor R, the current-limiting resistor R is electrically connected with a rectifying diode D, the rectifying diode D is electrically connected with an energy storage capacitor C, a normally closed contact KA1-1 and a normally open contact SB2 of an intermediate relay KA1 are electrically connected between the rectifying diode D and the capacitor C, the normally closed contact KA1-1 is electrically connected between the motor integrated protector WB and the normally open contact QF1 of the circuit breaker, and the normally open contact SB2 is in linkage with the normally closed contact SB 1; the normally open contact SB2 is electrically connected to the indicator lamp HW.

Further, the closing circuit comprises a starting button SB3, the starting button SB3 is electrically connected with a disconnecting switch QS, and the disconnecting switch QS is electrically connected with a closing coil HQ of the circuit breaker.

Further, two ends of the start button SB3 are connected in parallel with the central control switch SB4.

Further, a motor operation indicating circuit is electrically connected between the controlled power supplies, the motor operation indicating circuit of the pair comprises a normally open contact QF2 of the circuit breaker, and the normally open contact QF2 is connected with an indicating lamp HR.

Further, the output end of the motor integrated protector WB is connected with a fault circuit breaker, the fault circuit breaker comprises a process fault circuit breaker K05 and a starter fault circuit breaker K04, and the starter fault circuit breaker K04 is connected with the process fault circuit breaker K05 in parallel.

Compared with the prior art, the utility model has the beneficial effects that:

according to the utility model, the external energy storage element is matched with the intermediate relay KA1, so that when an external power grid fails and a power supply is lost, electric energy is released instantaneously to act on the switching-off tripping electromagnet, a moving contact and a fixed contact are reliably disconnected, and a high-voltage motor operation circuit is disconnected. Meanwhile, the utility model is provided with the indicator lamp HW, and the energy storage state can be detected in the normal working state through the cooperation of the normally open contact SB2 and the normally closed contact SB1, so that the integrity of the function of instantaneously releasing electric energy is maintained, and the potential safety hazards of operators and equipment in the production process are avoided.

Drawings

FIG. 1 is a schematic electrical diagram of a power loss trip of the present utility model;

FIG. 2 is a primary circuit schematic of the present utility model;

fig. 3 is a schematic diagram of a voltage measurement circuit of the present utility model.

Detailed Description

The utility model is further described below with reference to the accompanying drawings.

The embodiment 1, a control circuit of an automatic breaking breaker after the external power supply is powered off, as shown in fig. 1, includes a primary loop, the primary loop is connected with a voltage measurement loop through a transformer TV, the voltage measurement loop includes a voltmeter PV, an intermediate relay KA1 and an input end of a motor integrated protector WB, an output end of the motor integrated protector WB is arranged in an original breaking circuit, the original breaking circuit is electrically connected between controlled power supplies, and a closing circuit is arranged between the controlled power supplies; the primary opening circuit further comprises a normally open contact QF1 of the circuit breaker, the output end of the motor integrated protector WB is electrically connected with the normally open contact QF1, the normally open contact QF1 is electrically connected with an opening coil TQ of the circuit breaker, a secondary energy storage circuit is arranged between the controlled power supplies and comprises a normally closed contact SB1, the normally closed contact SB1 is electrically connected with a current-limiting resistor R, the current-limiting resistor R is electrically connected with a rectifying diode D, the rectifying diode D is electrically connected with an energy storage capacitor C, a normally closed contact KA1-1 and a normally open contact SB2 of an intermediate relay KA1 are electrically connected between the rectifying diode D and the capacitor C, the normally closed contact KA1-1 is electrically connected between the motor integrated protector WB and the normally open contact QF1 of the circuit breaker, and the normally open contact SB2 is in linkage with the normally closed contact SB 1; the normally open contact SB2 is electrically connected to the indicator lamp HW.

In the embodiment 2, a control circuit capable of automatically breaking a circuit breaker after an external power supply is powered off, wherein a closing circuit comprises a starting button SB3, the starting button SB3 is electrically connected with a disconnecting switch QS, and the disconnecting switch QS is electrically connected with a closing coil HQ of the circuit breaker; the two ends of the starting button SB3 are connected with a central control switch SB4 in parallel, and the central control switch SB4 is arranged in a central control room and controls the starting of the motor; the motor operation indicating circuit comprises a normally open contact QF2 of a circuit breaker, the normally open contact QF2 is connected with an indicator lamp HR, after a start button SB3 is pressed, a closing coil HQ is electrified, the normally open contact QF2 is closed, and the indicator lamp HR is lighted to indicate that the motor is electrified; the output end of the motor comprehensive protector WB is connected with a fault circuit breaker, the fault circuit breaker comprises a process fault circuit breaker K05 and a starter fault circuit breaker K04, and the starter fault circuit breaker K04 is connected with the process fault circuit breaker K05 in parallel; the other steps are the same as in example 1.

The operation control main loop of the high-voltage motor consists of an upper isolating switch QS, a voltage transformer TV, a normally open contact QF3 of a breaker, a current transformer TA, a zero sequence transformer TAN, a motor comprehensive protector WB and the like. As shown in fig. 2-3, the isolating switch QS is electrically connected with a normally open contact QF3 of the circuit breaker, the normally open contact QF3 is electrically connected with a zero sequence transformer TAN, a current transformer TA is arranged between the normally open contact QF3 and the zero sequence transformer TAN, the zero sequence transformer TAN is connected with a high-voltage motor, and the zero sequence transformer TAN is grounded; a voltage transformer TV is arranged between the isolating switch QS and the normally open contact QF3, the voltmeter PV and the intermediate relay KA1 are respectively and electrically connected to the auxiliary side of the voltage transformer TA, and when the upper isolating switch QS is closed, high voltage is sent to the upper end of the breaker QF, and the intermediate relay KA1 is attracted.

In a normal working state, the secondary side of the voltage transformer TV is provided with 100V alternating current output, the intermediate relay KA1 is attracted, and the normally closed contact KA1-1 of the intermediate relay KA1 is kept in an off state. The control power supply is subjected to half-wave rectification by a rectifier diode D after passing through a normally closed contact SB1 and then passing through a current limiting resistor R, and then charges a capacitor C. The normally closed contact SB1 is pressed down, the normally closed contact SB1 is opened, the path from the alternating current power supply to the positive electrode of the rectifier diode D is cut off, the normally open contact SB2 is closed, the intermediate relay KA1 is electrified due to the normal working state, the normally closed contact KA1-1 of the intermediate relay KA1 keeps the open state, the capacitor C cannot always close the node of the contact KA1-1 to supply power to the switching-off coil, and only the normally open contact SB2 can discharge power to the indicator lamp. If the normally closed contact SB1 is pressed down, the indicator light is on, and the charge and discharge functions and the energy storage functions of the capacitor C are normal.

After the high-voltage power-on operation is finished, a starting button SB3 is pressed, a switching-on coil HQ is electrified, a switching-on electromagnet acts to enable an energy storage maintaining shaft to rotate, a pawl is driven to loosen a roller, energy storage maintenance is released, a switching-on spring releases energy, a moving contact is pressed to a static contact circuit to be connected, a motor rotates, and the internal structure of the circuit breaker is in the prior art. When the external power source disappears, no alternating current is output at the secondary side of the voltage transformer TV, no current passes through the intermediate relay KA1, the normally closed contact KA1-1 of the intermediate relay KA1, the normally closed contact SB2 is disconnected, the capacitor C only can supply power to the normally open contact QF1 and the switching-off coil TQ of the circuit breaker, the internal structure of the circuit breaker is the prior art, the switching-off tripping electromagnet acts, the constraint of the holding pawl is released, and finally the moving and static contacts are separated by the energy stored by the over-travel spring and the switching-off spring, so that the automatic switching-off operation when the power source disappears after the external power grid breaks down is realized.

Claims (5)

1. The control circuit comprises a primary loop, wherein the primary loop is connected with a voltage measurement loop through a transformer TV, the voltage measurement loop comprises a voltmeter PV, an intermediate relay KA1 and a motor integrated protector WB, the output end of the motor integrated protector WB is arranged in an original brake separating circuit, the original brake separating circuit is electrically connected between controlled power supplies, and a brake closing circuit is arranged between the controlled power supplies; the original brake separating circuit also comprises a normally open contact QF1 of the circuit breaker, the output end of the motor integrated protector WB is electrically connected with the normally open contact QF1, and the normally open contact QF1 is electrically connected with a brake separating coil TQ of the circuit breaker, and the brake separating circuit is characterized in that: the secondary energy storage circuit comprises a normally closed contact SB1, the normally closed contact SB1 is electrically connected with a current-limiting resistor R, the current-limiting resistor R is electrically connected with a rectifying diode D, the rectifying diode D is electrically connected with an energy storage capacitor C, a normally closed contact KA1-1 and a normally open contact SB2 of an intermediate relay KA1 are electrically connected between the rectifying diode D and the capacitor C, the normally closed contact KA1-1 is electrically connected between the motor integrated protector WB and a normally open contact QF1 of a circuit breaker, and the normally open contact SB2 is in linkage with the normally closed contact SB 1; the normally open contact SB2 is electrically connected to the indicator lamp HW.

2. The control circuit for automatically breaking a circuit breaker after power failure of an external power supply according to claim 1, wherein: the switching-on circuit comprises a starting button SB3, the starting button SB3 is electrically connected with a disconnecting switch QS, and the disconnecting switch QS is electrically connected with a switching-on coil HQ of the circuit breaker.

3. The control circuit for automatically breaking a circuit breaker after external power failure according to claim 2, wherein: the two ends of the starting button SB3 are connected with a central control switch SB4 in parallel.

4. The control circuit for automatically breaking a circuit breaker after power failure of an external power supply according to claim 1, wherein: the motor operation indicating circuit is electrically connected between the controlled power supplies and comprises a normally open contact QF2 of the circuit breaker, and the normally open contact QF2 is connected with an indicating lamp HR.

5. The control circuit for automatically breaking a circuit breaker after power failure of an external power supply according to claim 1, wherein: the output end of the motor comprehensive protector WB is connected with a fault circuit breaker, the fault circuit breaker comprises a process fault circuit breaker K05 and a starter fault circuit breaker K04, and the starter fault circuit breaker K04 is connected with the process fault circuit breaker K05 in parallel.