CN216412900U - Three-position switch operating mechanism - Google Patents

Abstract

The utility model provides a three-position switch operating mechanism, and belongs to the field of high-voltage switch equipment. The three-station switch mechanism comprises a switching-on and switching-off control circuit, an excitation circuit, a motor control circuit and a motor driving circuit, wherein after the switching-on and switching-off control circuit receives and is conducted by a three-station switch operation instruction, the excitation circuit is conducted through a corresponding electric device in the circuit, an excitation electromagnet in the excitation circuit is electrified, so that a first microswitch in the motor control circuit is driven to be closed, a forward rotation control branch or a reverse rotation control branch in the motor control circuit is conducted, the motor driving circuit is conducted, the motor is electrified to rotate forwards or reversely, the three-station switch mechanism executes body action according to the operation instruction requirement, and an execution result is fed back. Compared with the prior art, the three-position switch operating mechanism provided by the utility model has the advantages that the number of micro switches and the installation and debugging workload are reduced, the cost is saved, the circuit structure is more compact, and the volume of high-voltage switch equipment is reduced.

Description

Three-position switch operating mechanism

Technical Field

The utility model provides a three-position switch operating mechanism, and belongs to the field of high-voltage switch equipment.

Background

The high-voltage switch equipment is used as an important node of a power system and plays an important role in safe and reliable operation of a power grid. The stable operation of the high-voltage switch operating mechanism is a good idea of the reliability of the high-voltage switch. Along with the continuous development of economic society, the land resource is more and more scarce, and urgent needs are brought to the miniaturization of high-voltage switch equipment, and the miniaturization of the switch equipment becomes possible due to the application of a composite insulation technology, a gas insulation technology and a miniaturized vacuum arc-extinguishing chamber, and the progress is further accelerated. At present, three-position switch equipment is widely applied to miniaturized combined electrical appliance products, in particular to 110kV and 220kV combined electrical appliance products.

As shown in fig. 1, the three-position switch apparatus has functions of both the disconnecting switch and the grounding switch, and has three operating position states, namely: (a) the grounding switch is opened, the isolating switch is closed, and the bus is connected; (b) the isolating switch is used for separating the brake, the grounding switch is used for separating the brake, and the bus is isolated; (c) the disconnecting switch is opened, the grounding switch is closed, and the disconnecting switch is connected to the grounding contact. The conversion of three working states is realized by the rotation of the motor and the movement of the contact driven by the transmission part: taking the initial positions of the opening of the grounding switch and the closing of the isolating switch as an example, the sequential conversion of the states a-b-c can be realized by clockwise rotation of the motor (namely forward rotation of the motor), and the sequential conversion of the states c-b-a can be realized by counterclockwise rotation of the motor (namely reverse rotation of the motor).

Domestic three-position switch operating mechanisms are roughly divided into two types: (1) the method is characterized in that double motors are adopted, the motors generally adopt alternating current series excitation motors, as shown in fig. 2, a motor M1 is adopted for the opening and closing control of the isolating switch, the closing and the opening of the isolating switch are respectively realized by the positive rotation and the negative rotation of the motor, after the moving contact moves in place, a rotating loop is cut off by means of microswitches SLE and SLA, the rotating loop is switched to a motor braking loop, and the energy consumption braking is realized by means of a resistor R1; the grounding switch is controlled to be switched on and off by adopting another motor M2, and the control process is the same as that of the isolating switch. (2) The single motor is adopted, the motor generally adopts a direct current permanent magnet motor, the switching-on and switching-off of the switch are realized by the positive rotation and the negative rotation of the motor, the switching-on in-place of the isolating switch, the switching-off in-place of the isolating switch, the switching-on in-place of the grounding switch and the switching-off in-place of the grounding switch are respectively realized by 4 micro switches, and the braking is finished by an external resistor.

Aiming at the control of a three-position switch operating mechanism, in order to reduce the complexity of a control loop, improve the running reliability of a motor and reduce the failure rate, people make some improvements through a great deal of exploration, but still have the following defects:

(1) the state switching of the motor needs to be completed by 4 micro switches together, on one hand, the installation of the micro switches increases the overall size of the mechanism box, and the mechanism box is contrary to the miniaturization and compact target of the combined electrical appliance; on the other hand, the 4 micro switches are difficult to control in the process of installation, positioning and action matching adjustment, and the debugging time is long. If the position of the microswitch is not adjusted in place, even after the switch body is switched off (or switched on), the loop can not be switched in time, so that the phenomenon that the motor is blocked, rotated and burnt out occurs, and the transmission part is damaged in different degrees.

(2) The motor control loop adopts a conventional relay, the size is large, the workload of wiring between the relays is large, and in a compact mechanism box body, the replacement and maintenance of electrical elements are difficult.

(3) In order to realize monitoring and trend evaluation of equipment states, the intelligent substation provides specific requirements for functions of double confirmation of 'second criterion' of the on-off position of the isolating grounding switch, motor current acquisition and analysis and the like, but the existing three-position switch operating mechanism does not have the function.

In summary, the high-voltage switch equipment using the three-position switch in the prior art is large in size and high in cost.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a three-position switch operating mechanism which is used for solving the problems of large volume and high cost of high-voltage switch equipment using a three-position switch in the prior art.

In order to achieve the purpose, the utility model provides a three-position switch operating mechanism, which comprises a switching-on and switching-off control circuit, an excitation circuit, a motor control circuit and a motor drive circuit, wherein the switching-on and switching-off control circuit is used for receiving a three-position switch operating instruction to conduct the excitation circuit;

the three-station switch operation comprises grounding switch opening, grounding switch closing, disconnecting switch opening and disconnecting switch closing;

the excitation loop comprises an excitation electromagnet, and the motor control loop comprises a forward rotation control branch for controlling the forward rotation of the motor, a reverse rotation control branch for controlling the reverse rotation of the motor and a first microswitch; the forward rotation control branch and the reverse rotation control branch are connected in parallel and then connected in series with the first microswitch;

when the excitation electromagnet is electrified, the first microswitch is driven to be closed, and when the forward rotation control branch or the reverse rotation control branch is conducted, the motor driving loop drives the motor to rotate forward or reversely, so that the corresponding three-station switch operation is realized; when the three-position switch body reaches a preset grounding switch opening position, a grounding switch closing position, an isolating switch opening position or an isolating switch closing position, the first microswitch is disconnected.

The three-position switch operating mechanism comprises a switching-on and switching-off control circuit, an excitation circuit, a motor control circuit and a motor driving circuit, wherein the switching-on and switching-off control circuit receives and is conducted with a three-position switch operating instruction, and then conducts the excitation circuit through a corresponding electric device in the circuit to enable an excitation electromagnet in the excitation circuit to be electrified, so that a first microswitch in the motor control circuit is driven to be closed, a true-Ga-mixed control branch or a reverse rotation control branch in the motor control circuit is conducted, the motor driving circuit is conducted, the motor is electrified to rotate forwards or reversely, and the three-position switch body acts to execute the corresponding three-position switch operating instruction. Compared with the prior art, the three-position switch operating mechanism has the advantages that the number of micro switches is reduced, the cost is reduced, the circuit structure is more compact, and the volume of high-voltage switch equipment is reduced.

Further, in the three-position switch operating mechanism, the switching-on/off control circuit comprises a grounding switch switching-off circuit, a grounding switch switching-on circuit, an isolating switch switching-off circuit and an isolating switch switching-on circuit which are connected in parallel;

the grounding switch opening loop comprises a grounding switch opening relay coil, the grounding switch closing loop comprises a grounding switch closing relay coil, the isolating switch opening loop comprises an isolating switch opening relay coil, and the isolating switch closing loop comprises an isolating switch closing relay coil;

the device also comprises an excitation branch circuit; the first normally open contact of the grounding switch opening relay, the first normally open contact of the grounding switch closing relay, the first normally open contact of the isolating switch opening relay and the first normally open contact of the isolating switch closing relay are connected in parallel to form a first branch circuit, and the first branch circuit is connected with an excitation relay coil in series to form an excitation branch circuit;

the excitation loop further comprises a normally open contact of an excitation relay, and the normally open contact of the excitation relay is connected with the excitation electromagnet in series.

Aiming at the opening and closing control circuit and the function of the opening and closing control circuit for conducting the excitation circuit, a specific circuit structure is provided, corresponding opening and closing relay coils in the opening and closing control circuit act on corresponding normally open contacts in the excitation branch circuit, so that the excitation branch circuit is conducted, the excitation relay coils in the excitation branch circuit are electrified, the normally open contacts of the excitation relay in the excitation branch circuit are closed, and the excitation electromagnet is electrified.

Further, in the three-station switch operating mechanism, the ground switch opening loop further includes a first normally closed contact of a ground switch closing relay and a first normally closed contact of an isolating switch opening relay, which are connected in series with a ground switch opening relay coil;

the grounding switch closing circuit also comprises a first normally closed contact of a grounding switch opening relay and a first normally closed contact of an isolating switch closing relay which are connected with a grounding switch closing relay coil in series;

the isolating switch opening loop further comprises a second normally closed contact of the grounding switch opening relay AY and a second normally closed contact of the isolating switch closing relay, wherein the second normally closed contact of the grounding switch opening relay AY and the second normally closed contact of the isolating switch closing relay are connected with the isolating switch opening relay coil in series;

the isolating switch closing circuit further comprises a second normally closed contact of the grounding switch closing relay and a second normally closed contact of the isolating switch opening relay, wherein the second normally closed contacts are connected with the isolating switch closing relay coil in series.

The normally closed contacts of the corresponding relays are arranged in the opening and closing control loops of the isolating and grounding switches, so that the motor can execute an instruction of moving towards the other direction after moving in place towards one direction.

Further, in the three-position switch operating mechanism, the three-position switch operating mechanism further includes a second micro switch and a holding loop for holding the excitation branch to be powered off, the second micro switch includes a first contact group, the first contact group includes a first moving contact and two corresponding fixed contacts, and the first moving contact and one of the fixed contacts of the second micro switch are connected in series in the excitation branch;

the holding loop comprises a coil of a holding relay, one end of the coil of the holding relay is connected with the other fixed contact of the second microswitch, and the other end of the coil of the holding relay is connected between the coil of the excitation relay and the first branch circuit;

and a normally closed contact of the holding relay is connected in series with the exciting relay coil, and a normally open contact of the holding relay is connected in series with the holding relay coil and used for continuously electrifying the holding relay coil.

The second microswitch and the holding loop are also arranged, the coil of the holding relay is arranged in the holding loop, the normally closed contact of the holding relay is connected with the exciting relay coil in series, and the normally open contact of the holding relay is connected with the holding relay coil in series, so that the situation that the power supply of the exciting relay coil cannot be reliably cut off when the second microswitch breaks down is prevented, and the burning loss of the exciting electromagnet is prevented.

Further, in the three-position switch operating mechanism, a third microswitch for switching between manual control and electric control is further included, and the third microswitch includes two pairs of normally closed contacts; the grounding switch opening loop and the grounding switch closing loop are connected in parallel and then connected in series with one pair of normally closed contacts of the third microswitch, and the isolating switch opening loop and the isolating switch closing loop are connected in parallel and then connected in series with the other pair of normally closed contacts of the third microswitch; when the crank is inserted into the corresponding crank hole of the three-position switch operating mechanism, the normally closed contact of the third microswitch is triggered to be disconnected.

The switch-on and switch-off control loop of the isolation and grounding switch is connected with a power supply through the normally closed contact of the third microswitch, and when the crank is inserted into the corresponding crank hole of the three-position switch operating mechanism, the normally closed contact of the third microswitch is triggered to be disconnected, so that the switch-on and switch-off control loop is switched on.

Further, in the three-station switch operating mechanism, the forward rotation control branch comprises a forward rotation contactor coil, a second normally open contact of the grounding switch closing relay and a second normally open contact of the isolating switch opening relay, and the second normally open contact of the grounding switch closing relay and the second normally open contact of the isolating switch opening relay are connected in parallel and then are connected in series with the forward rotation contactor;

the reverse control branch circuit comprises a reverse contactor coil, a second normally open contact of the grounding switch opening relay and a second normally open contact of the isolating switch closing relay, and the second normally open contact of the grounding switch opening relay and the second normally open contact of the isolating switch closing relay are connected in parallel and then connected with the reverse contactor in series.

Aiming at the forward and reverse control branches, a specific implementation mode is provided, and the normally open contact of the corresponding opening and closing relay is connected with the coils of the forward and reverse contactors, so that the opening and closing control loop can reliably control the motor control loop, and the safety of the circuit is enhanced.

Further, in the three-station switch operating mechanism, the motor driving circuit comprises a first normally open contact of the forward contactor, a motor rotor winding, a second normally open contact of the forward contactor, a motor stator winding and a third normally open contact of the forward contactor which are sequentially connected in series;

still include the first normally open contact of reversal contactor, reversal contactor second normally open contact and reversal contactor third normally open contact, the first normally open contact of reversal contactor is parallelly connected with the first normally open contact of corotation contactor, and reversal contactor second normally open contact is parallelly connected at the both ends behind corotation contactor second normally open contact and the motor stator winding series connection, and reversal contactor third normally open contact is parallelly connected at the both ends behind motor stator winding and the corotation contactor third normally open contact series connection.

Aiming at the motor driving loop, a specific implementation mode is provided, and the motor is driven to rotate forwards and backwards by changing the direction of current input to a field coil of the motor, so that the current acts on the three-position switch body to realize corresponding operation.

Furthermore, in the three-station switch operating mechanism, the three-station switch operating mechanism further comprises a fourth normally open contact of the reverse contactor, a fifth normally open contact of the reverse contactor, a fourth normally open contact of the forward contactor, and a fourth normally open contact of the forward contactor, wherein the fourth normally open contact of the reverse contactor is connected with the switching-off command input end of the grounding switch in parallel, the fifth normally open contact of the reverse contactor is connected with the switching-on command input end of the isolating switch in parallel, the fourth normally open contact of the forward contactor is connected with the switching-off command input end of the grounding switch in parallel, and the fourth normally open contact of the forward contactor is connected with the switching-off command input end of the isolating switch in parallel.

When the input switching-on and switching-off control instruction is an instantaneous instruction, the normally open contacts of the alignment relay and the reverse relay are connected in series between the corresponding switching-on and switching-off control loop and the power supply input end, so that the reliable conduction of the circuit is realized when the motor rotates forwards and reversely.

Further, the three-position switch operating mechanism further comprises a motor brake control loop, wherein the motor brake control loop comprises a double-position relay coil, a first coil of the double-position relay coil is connected with a sixth normally open contact of the forward contactor, and a second coil of the double-position relay coil is connected with a sixth normally open contact of the reverse contactor;

the motor driving circuit also comprises a first single-pole double-throw switch and a second single-pole double-throw switch, wherein a moving contact of the first single-pole double-throw switch is connected between a first normally open contact of the forward contactor and a motor rotor winding after being connected with a first normally closed contact of the forward contactor and a first normally closed contact of the reverse contactor in series; a first fixed contact of the first single-pole double-throw switch is connected with a second fixed contact of the second single-pole double-throw switch and then connected between a second normally open contact of the forward rotation contactor and a motor stator winding, and a second fixed contact of the first single-pole double-throw switch is connected with a first fixed contact of the second single-pole double-throw switch and then connected between the motor stator winding and a third normally open contact of the forward rotation contactor;

when a first coil of the double-position relay coil is electrified, a moving contact of a first single-pole double-throw switch is closed with a first fixed contact of the first single-pole double-throw switch, and a moving contact of a second single-pole double-throw switch is closed with the first fixed contact of the second single-pole double-throw switch;

when the second coil of the double-position relay coil is electrified, the moving contact of the first single-pole double-throw switch is closed with the second fixed contact of the first single-pole double-throw switch, and the moving contact of the second single-pole double-throw switch is closed with the second fixed contact of the second single-pole double-throw switch.

A motor brake control loop is additionally arranged in the three-position switch operating mechanism, so that the motor brake function is realized. The motor brake control loop is realized by a double-position relay, the double-position relay comprises two coils and two single-pole double-throw switches, and one coil is connected with a power supply through a normally open contact of a forward rotation contactor to realize forward rotation brake of the motor; and the other coil is connected with a power supply through a normally open contact of the reverse contactor, so that the reverse braking of the motor is realized.

Further, in the three-position switch operating mechanism, a detection loop for detecting the operating state of the three-position switch is further included, and the detection loop includes a second contact group of a second microswitch;

the second contact group is connected with the grounding switch opening signal detection interface through a third normally open contact of the grounding switch opening relay, the second contact group is connected with the grounding switch closing signal detection interface through a third normally open contact of the grounding switch closing relay, the second contact group is connected with the isolating switch opening signal detection interface through a third normally open contact of the isolating switch opening relay, and the second contact group is connected with the isolating switch closing signal detection interface through a third normally open contact of the isolating switch closing relay.

The utility model provides a detection circuit for detecting the switching-on and switching-off states of a three-position switch operating mechanism, wherein a pair of normally open contacts of a corresponding switching-on and switching-off relay are connected in parallel with each other and then are connected with the other group of contacts of a second microswitch, when a motor rotates forwards and backwards, the group of contacts are closed, the normally open contacts of the relay corresponding to switching-on and switching-off instructions are closed, so that corresponding switching-on and switching-off signals are output, the signals are displayed through a signal lamp or other modes, and the three-position switch operating state can be accurately judged.

Drawings

FIG. 1 is a schematic diagram of three positions of a prior art three position switch;

FIG. 2 is a schematic diagram of a control loop of a prior art three-position operating mechanism using dual motors;

FIG. 3 is a schematic diagram of a control loop of a three-position switch operating mechanism in an embodiment of the present invention;

FIG. 4 is a schematic diagram of a motor circuit of a three-position switch operating mechanism according to an embodiment of the present invention;

FIG. 5 is a schematic view of a detection circuit of the three-position switch operating mechanism in the embodiment of the present invention;

FIG. 6 is a schematic diagram of a control circuit board of the three-position switch operating mechanism according to the embodiment of the present invention;

fig. 7 is a schematic diagram of state detection of a three-position switch operating mechanism of a transformer substation in the embodiment of the utility model.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments.

Three station switch operating device embodiments:

the three-position switch operating mechanism in the embodiment comprises a control circuit, a motor circuit and a detection circuit. The control circuit is shown in fig. 3 and comprises a microswitch LS4, a microswitch LS6, an earthing switch opening relay AY, an earthing switch closing relay AX, a disconnecting switch opening relay AX2, a disconnecting switch closing relay AY2, an exciting relay Z, a holding relay Z1 and an exciting electromagnet RC.

The microswitch LS4 is used for realizing manual/electric switching of the mechanism operation mode, as shown in FIG. 3, two pairs of normally open contacts of the microswitch LS4 are in an off state, and the three-position switch operation mechanism is in a manual control state; in other embodiments, when both pairs of normally open contacts of the microswitch LS4 in fig. 3 are closed, the three-position switch operating mechanism is in an electric control state.

In the present embodiment, in order to protect exciting electromagnet RC, exciting relay Z and exciting electromagnet RC are reliably cut off by providing holding relay Z1.

The microswitch LS6 comprises two groups of contacts, wherein one group of contacts as shown in fig. 3 comprises a moving contact and two fixed contacts, and is arranged in a control loop, so that the contacts can be switched according to the actual rotating position of the motor; the other group of contacts is shown in fig. 5, and comprises a fixed contact and a movable contact, which are arranged in the detection loop, so that the 'second criterion' determination of the on/off position states of the disconnecting switch and the grounding switch can be realized.

The earthing switch opening relay AY, the earthing switch closing relay AX, the isolating switch opening relay AX2 and the isolating switch closing relay AY2 adopted in the embodiment all comprise 3 pairs of normally open contacts and 2 pairs of normally closed contacts, wherein 1 pair of normally open contacts are arranged in a control loop and are electrically or manually controlled by a microswitch LS 4; the normally open contacts are arranged in the motor loop and used for controlling the conduction of a forward and reverse control branch in the motor loop; 1 pairs of normally open points are arranged in a detection loop and used for confirming the second criterion of the opening and closing positions of the disconnecting switch and the grounding switch; and 2, the pair of normally closed contacts are arranged in the control loops and used for realizing logic interlocking among different opening and closing control loops and ensuring that the motor can execute an instruction of moving towards the other direction after moving towards one direction to the right.

The motor loop comprises a forward contactor X, a reverse contactor Y, a micro switch LS1, a motor M, a double-position relay KL and a current transmitter. The forward contactor X and the reverse contactor Y are used for controlling forward rotation and reverse rotation of the motor M; the motor M drives the transmission mechanism through positive and negative rotation to act on corresponding gears and racks and drives the output shaft to act on the cam, so that the opening and closing movement of the three-station switch body is realized; the current transducer is used for realizing the collection of current.

The two-position relay KL in this embodiment includes two coils, and can switch the motor braking circuit through set/reset state, realize the reliable brake of motor.

In this embodiment, when the microswitch LS1 is in the equilibrium position, the moving contact COM and the normally open contact NO are closed, and when the exciting electromagnet RC is energized, the state of the microswitch LSI is switched, and the moving contact COM and the normally closed contact NC are closed. When the motor rotates forwards or reversely, the three-position switch body reaches the switch-off position of the grounding switch, the switch-on position of the grounding switch, the switch-off position of the disconnecting switch or the switch-on position of the disconnecting switch as shown in fig. 1, the cam in the transmission structure is driven to press off the microswitch LS1, so that the moving contact COM of the three-position switch body is disconnected from the normally closed contact NC, and the three-position switch body is restored to the balance position.

In this embodiment, the ground switch opening circuit is formed by connecting a coil of the ground switch opening relay AY, one pair of normally closed contacts of the ground switch closing relay AX, and one pair of normally closed contacts of the disconnecting switch opening relay AX2 in series in sequence. One end of the opening loop of the grounding switch is connected with the negative terminal of the grounding switch control power supply through a normally open contact (5-6) of the microswitch LS 4. The other end of the grounding switch opening loop is connected with the positive terminal of the grounding switch opening control power supply through a normally open contact of the grounding switch, and is also connected with the positive terminal of the control power supply through one pair of normally open contacts of the reversing contactor Y.

The grounding switch closing loop is formed by connecting a coil of a grounding switch closing relay AX in series with one pair of normally closed contacts of a grounding switch opening relay AY and one pair of normally closed contacts of an isolating switch closing relay AY 2. One end of the grounding switch closing loop is connected with the negative terminal of the grounding switch control power supply through a normally open contact (5-6) of the microswitch LS 4. The other end of the grounding switch closing loop is connected with the positive terminal of the grounding switch closing control power supply through a grounding switch normally closed contact and is also connected with the positive terminal of the control power supply through one pair of normally open contacts of the forward rotation contactor X.

The isolating switch opening loop is formed by connecting a coil of an isolating switch opening relay AX2 with the other pair of normally closed contacts of the grounding switch opening relay AY and the other pair of normally closed contacts of the isolating switch closing relay AY2 in series. One end of the disconnecting switch opening loop is connected with the negative electrode terminal of the disconnecting switch control power supply through a normally open contact (1-2) of the micro switch LS 4. The other end of the isolating switch opening loop is connected with the positive terminal of the isolating switch opening control power supply through an isolating switch normally-open contact and is also connected with the positive terminal of the control power supply through one pair of normally-open contacts of the forward rotation contactor X.

The isolating switch closing loop is formed by connecting a coil of an isolating switch closing relay AY2 with the other pair of normally closed contacts of the grounding switch closing relay AX and the other pair of normally closed contacts of an isolating switch opening relay AX2 in series. One end of the closing loop of the isolating switch is connected with the negative terminal of the isolating switch control power supply through a normally open contact (1-2) of the micro switch LS 4. The other end of the isolating switch closing loop is connected with the positive terminal of the isolating switch closing control power supply through an isolating switch normally-closed contact and is also connected with the positive terminal of the control power supply through one pair of normally-open contacts of the reversing contactor Y.

In this embodiment, the control circuit further includes a first branch, and the first branch is formed by connecting in parallel one of a pair of normally open contacts of the ground switch opening relay AY, one of a pair of normally open contacts of the ground switch closing relay AX, one of a pair of normally open contacts of the disconnecting switch opening relay AX2, and one of a pair of normally open contacts of the disconnecting switch closing relay AY 2. One end of the first branch is connected with the negative electrode of the control power supply; the other end of the excitation relay Z is sequentially connected with a coil of the excitation relay Z and a normally closed contact of the holding relay Z1 in series and then connected with a first static contact NO of the microswitch LS 6. The other end of the first branch is also connected with a second static contact NC of the microswitch LS6 through a coil of a holding relay Z1.

The moving contact COM of the microswitch LS6 is connected with the positive terminal of the control power supply. One end of a normally open contact of the holding relay Z1 is connected with a positive terminal of a control power supply, and the other end of the normally open contact is connected between a coil of the holding relay Z1 and a second static contact of the microswitch LS 6. Two pairs of normally open contacts of the excitation relay Z are connected in series and then are connected in series with the excitation electromagnet RC to form an excitation branch. One end of the excitation branch is connected with the positive terminal of the control power supply, and the other end of the excitation branch is connected with the negative terminal of the control power supply.

When the coil of the holding relay Z1 is electrified, the normally open contact is closed, so that the coil can be continuously electrified; the normally closed contact is disconnected, so that the coil of the exciting relay Z is reliably de-energized, the exciting electromagnet RC cannot be energized for a long time, and the service life of the exciting electromagnet is prolonged.

The normally closed contact (3-4) of the microswitch LS4 is connected with the manual operation button BS (13-14) in series and then connected with the first branch in parallel.

As shown in fig. 4, the pair of normally open contacts AY (7-11) of the ground switch opening relay AY is connected in parallel with the pair of normally open contacts AY2(7-11) of the disconnecting switch closing relay AY2, and then connected in series with the coil Y (a1-a2) of the reversing contactor Y to form a reversing control branch. One end of the reverse control branch is used for connecting a motor L (live wire), and the other end of the reverse control branch is connected with a normally closed contact NC of the microswitch LS 1.

A pair of normally open contacts AX (7-11) of the grounding switch closing relay AX and a pair of normally open contacts AY2(7-11) of the isolating switch opening relay AX2 are connected in parallel and then connected in series with a coil X (A1-A2) of the forward rotation contactor X to form a forward rotation control branch. One end of the forward rotation control branch is connected with a normally closed contact NC used for being connected with a motor L (live wire), and the other end of the forward rotation control branch is connected with a microswitch LS 1. The moving contact COM of the microswitch LS1 is connected to the motor N (neutral line) via a current transducer. The motor L and the motor N can be connected with a DC power supply or an AC power supply.

Normally open contacts (53-54) of the forward contactor X and normally open contacts (53-54) of the reverse contactor Y are connected in parallel to a terminal 2 and a terminal 1 of a two-position relay KL coil, and a terminal 10 and a terminal 11 of the two-position relay KL coil are connected with a motor N through a current transducer.

One end BK of a rotor winding BK-RE of the motor M is connected with the motor L through a normally open contact (1-2) of the forward rotation contactor X, and the other end RE is connected with one end, far away from the motor N, of the current transmitter after being sequentially connected with the normally open contact (3-4) of the forward rotation contactor X, a motor stator winding BL-GR and the normally open contact (5-6) of the forward rotation contactor X in series. Normally open contacts (1-2) of the reverse contactor Y are connected with normally open contacts (1-2) of the forward contactor X in parallel, normally open contacts (3-4) of the reverse contactor Y are connected with normally open contacts (3-4) of the forward contactor X and two ends of a motor stator winding BL-GR in parallel, and normally open contacts (5-6) of the reverse contactor Y are connected with normally open contacts (5-6) of the forward contactor X and two ends of a motor stator winding BL-GR in parallel.

The two-position relay KL includes two sets of contacts, the first set of contacts includes a movable contact 3, a stationary contact 4, and a stationary contact 5, and the second set of contacts includes a movable contact 9, a stationary contact 7, and a stationary contact 8. And the static contact 5 is also connected with a wire between the motor stator winding BL-GR and a normally open contact (5-6) of the forward contactor X after being connected with the static contact 8, and the static contact 4 is also connected with a wire between the motor stator winding BL-GR and a normally open contact (3-4) of the forward contactor X after being connected with the static contact 7. The moving contact 9 is connected with the end RE of the rotor winding of the motor M after being sequentially connected with the normally closed contacts (61-62) of the reverse rotation contactor Y and the normally closed contacts (61-62) of the forward rotation contactor X in series. The moving contact 3 is connected with the rotor winding BK end of the motor M after being sequentially connected with the normally closed contacts (21-22) of the reverse rotation contactor Y and the normally closed contacts (21-22) of the forward rotation contactor X in series.

When the isolating switch QS needs to be controlled to be switched off, a normally open contact QS of the isolating switch is temporarily closed, contacts (1-2) of a microswitch LS4 are manually closed through a crank, a coil of an isolating switch switching-off relay AX2 is electrified, a normally open contact of an isolating switch switching-off relay AX2 in a first branch is closed, and a normally open contact (7-11) of an isolating switch switching-off relay AX2 in a motor loop is closed. At the moment, the micro-switch LS6 is pressed by a cam, a moving contact COM and a first fixed contact NC of the micro-switch LS6 are closed, a coil of an exciting relay Z is electrified, two pairs of normally open contacts of the exciting relay Z in an exciting branch circuit are closed, an exciting electromagnet RC is electrified instantly, the moving contact COM and the fixed contact NC of the micro-switch LS1 are closed, the coil of a forward rotating contactor X is electrified, normally open contacts (1-2), (3-4), (5-6) and (53-54) of the forward rotating contactor X in a motor loop are all closed, normally closed contacts (21-22) and (61-62) are all opened, the normally open contact of the forward rotating contactor X in the control loop is closed, and the coil of an isolating switch separating relay AX2 is ensured to be electrified continuously. At the moment, the normally open contact of the forward contactor X is closed, so that the setting coils (2-10) of the two-position relay KL are electrified, the movable contact 3 and the fixed contact 4 of the two-position relay KL are closed, and the movable contact 9 and the fixed contact 8 are closed.

Current flows from the motor L to the motor N sequentially through the normally open contacts (1-2) of the forward contactor X, the rotor winding BK-RE of the motor M, the normally open contacts (3-4) of the forward contactor X, the motor stator winding BL-GR, the normally open contacts (5-6) of the forward contactor X and the current transmitter. At the moment, the motor rotates forwards to open the QS isolating switch.

When the motor rotates forwards, the moving contact COM of the microswitch LS6 and the normally closed contact N0 are closed, the coil of the relay Z1 is kept electrified, the normally open contact of the relay Z1 is kept closed, the normally closed contact is opened, the coil of the exciting relay Z is reliably powered off, and therefore reliable power loss of the exciting electromagnet RC is guaranteed, and the exciting electromagnet RC is prevented from being burnt.

When the motor rotates in place, the microswitch LS1 is pressed off by the cam, the moving contact COM and the static contact NC are disconnected, the forward rotating contactor X loses electricity, the normally open contacts (1-2), (3-4), (5-6) and (53-54) of the forward rotating contactor X are disconnected, and the normally closed contacts (21-22) and (61-62) are closed. The motor M forms a brake circuit through BK → RE → X (61,62) → Y (61,62) → KL (9,8) → BL-GR → KL (4,3) → Y (22,21) → X (22,21) → BK, and the energy-consuming braking process of the motor M is completed.

The opening control process of the grounding switch QE is similar to that of the isolating switch QS, and the difference is that when the grounding switch QE is switched on, a coil of the grounding switch closing relay AX is electrified, a normally open auxiliary contact of the grounding switch closing relay AX is closed, and a normally closed auxiliary contact is opened.

The reverse rotation of the motor M can realize the switching on of an isolating switch QS and the switching off of a grounding switch QE. The control process is illustrated by taking the ground switch QE as an example. When the control circuit receives a brake-separating instruction (a remote signal or a local signal) of the ground switch QE, the coil of the brake-separating relay AY of the ground switch is electrified, the normally closed contact of the brake-separating relay AY is disconnected, and the normally open contact of the brake-separating relay AY is closed. The coil of the exciting relay Z in the control loop is electrified, the normally open contact of the exciting relay Z is closed, the exciting electromagnet RC is electrified, the state of the microswitch LS1 in the motor loop is switched, the reverse loop is switched on, the coil of the reverse contactor Y is electrified, the normally open contact of the reverse contactor Y is closed, and the normally closed contact of the reverse contactor Y is disconnected. The current is looped through the motor L → Y (1,2) → m (bk) → m (re) → Y (3,4) → m (gr) → m (bl) → Y (5,6) → current transmitter → the motor N, the motor rotates reversely, and the ground switch QE is closed.

When the motor M is reversely rotated to a certain position, the micro switch LSI is pressed off by the cam, the reverse contactor Y is de-energized, and a braking loop is formed by current passing through M (BK) → M (RE) → X (61,62) → Y (61,62) → KL (7,9) → M (BL) → M (GR) → KL (3,5) → Y (21,22) → X (21,22) → M (BK), so that the motor is braked and stopped.

In order to meet the high-level application requirements of 'one-key sequential control' of a transformer substation (an operation mode of prefabricating operation project software, building an operation task module, automatically judging equipment states, intelligently checking error-proof interlocking, starting an operation step by one key and automatically and sequentially executing an operation process), the 'second criterion' determination needs to be carried out on the on-off position states of an isolating switch and an earthing switch, and the determination principle is different from that of an auxiliary switch and is different from that of the auxiliary switch. The three-position switch operating mechanism further comprises a detection circuit, as shown in fig. 5, for confirming the on/off position states of the disconnecting switch and the grounding switch according to a second criterion.

The detection loop comprises a second group of contacts of the micro switch LS6, one end of one pair of normally open contacts of the grounding switch separating relay AY is connected with the moving contact of the micro switch LS6, and the other end of the pair of normally open contacts of the grounding switch separating relay AY is connected with a ground switch QE on-position detection terminal; one end of one pair of normally open contacts of the grounding switch closing relay AX is connected with a moving contact of a microswitch LS6, and the other end of the normally open contacts of the grounding switch closing relay AX is connected with a grounding switch QE position division detection terminal; one end of one pair of normally open contacts of the isolating switch opening relay AX2 is connected with a moving contact of a microswitch LS6, and the other end of the normally open contacts is connected with a QS position division detection terminal of the isolating switch; one end of one pair of normally open contacts of the isolating switch closing relay AY2 is connected with a moving contact of the microswitch LS6, and the other end of the normally open contacts is connected with a QS closing detection terminal of the isolating switch; the static contact of the microswitch LS6 is connected with the public end for supplying power.

Taking the opening of the isolating switch as an example, the process of confirming the position state of the isolating and grounding switch by the detection loop according to the second criterion is explained. When the isolating switch QS is switched off, a moving contact and a fixed contact of a microswitch LS6 in the detection loop are closed, and a pair of normally open contacts of an isolating switch tripping relay AX2 in the detection loop is closed, so that the detection loop is conducted, an instant QS-position detection signal is output, and the signal can be displayed through a signal lamp or act on other circuits.

In order to meet the requirement of compactness of the mechanism box and facilitate the overhaul and maintenance of a control loop, on-board relays are applied to replace the traditional relays, wiring among the relays is completed in a circuit board, and only necessary interfaces are reserved outwards, as shown in fig. 6. By the aid of the method, space of a mechanism box is saved, wiring and debugging workload under the condition of adopting a traditional intermediate relay are greatly reduced, and accordingly increased fault risk is reduced. Meanwhile, the circuit board occupies a small space, is convenient to replace and is beneficial to maintenance. When the circuit board breaks down, can directly change, interchangeability is good, and it is convenient to overhaul and maintain. The external interface meets the requirement of the expansion of the loop function, and if the control loop needs to access other external locking conditions and the like, the external interface only needs to be expanded without changing the circuit in the panel.

In order to meet the construction requirements of the existing intelligent substation, the three-position switch operating mechanism of the embodiment adopts a comprehensive fault intelligent diagnosis system for monitoring and controlling the current of the motor and the temperature and humidity of the mechanism box, as shown in fig. 7. A motor current sensor, a temperature and humidity controller, a damp-dispelling heater controlled by the temperature and humidity controller and the like are arranged in the mechanism box, information such as current, temperature, humidity and auxiliary switch switching value is collected through a monitoring unit, and communication with a collector deployed on site in a transformer substation is achieved in a wireless mode. The sensor adopts a wireless Lora433 wireless communication unit, and a built-in hardware SM1 or SM7 encryption chip, so that the communication is safer. The total station collector is uniformly networked and accessed to a background management and analysis server. The server stores, monitors and extracts the characteristics of the motor current signals, and establishes a comprehensive fault intelligent diagnosis system by using analysis means such as a neural network and the like and combining information such as temperature and humidity, opening and closing states and the like based on the extracted characteristics.

Claims (10)

1. The three-position switch operating mechanism is characterized by comprising a switching-on and switching-off control circuit, an excitation circuit, a motor control circuit and a motor drive circuit, wherein the switching-on and switching-off control circuit is used for receiving a three-position switch operating instruction to conduct the excitation circuit;

the three-station switch operation comprises grounding switch opening, grounding switch closing, disconnecting switch opening and disconnecting switch closing;

the excitation loop comprises an excitation electromagnet, and the motor control loop comprises a forward rotation control branch for controlling the forward rotation of the motor, a reverse rotation control branch for controlling the reverse rotation of the motor and a first microswitch; the forward rotation control branch and the reverse rotation control branch are connected in parallel and then connected in series with the first microswitch;

when the excitation electromagnet is electrified, the first microswitch is driven to be closed, and when the forward rotation control branch or the reverse rotation control branch is conducted, the motor driving loop drives the motor to rotate forward or reversely, so that the corresponding three-station switch operation is realized; when the three-position switch body reaches a preset grounding switch opening position, a grounding switch closing position, an isolating switch opening position or an isolating switch closing position, the first microswitch is disconnected.

2. The three-position switch operating mechanism according to claim 1, wherein the switching-on/off control circuit comprises a grounding switch switching-off circuit, a grounding switch switching-on circuit, an isolating switch switching-off circuit and an isolating switch switching-on circuit which are connected in parallel with each other;

the grounding switch opening loop comprises a grounding switch opening relay coil, the grounding switch closing loop comprises a grounding switch closing relay coil, the isolating switch opening loop comprises an isolating switch opening relay coil, and the isolating switch closing loop comprises an isolating switch closing relay coil;

the device also comprises an excitation branch circuit; the first normally open contact of the grounding switch opening relay, the first normally open contact of the grounding switch closing relay, the first normally open contact of the isolating switch opening relay and the first normally open contact of the isolating switch closing relay are connected in parallel to form a first branch circuit, and the first branch circuit is connected with an excitation relay coil in series to form an excitation branch circuit;

the excitation loop further comprises a normally open contact of an excitation relay, and the normally open contact of the excitation relay is connected with the excitation electromagnet in series.

3. The three-position switch operating mechanism according to claim 2, wherein the ground switch opening circuit further comprises a first normally closed contact of a ground switch closing relay, a first normally closed contact of a disconnecting switch opening relay, and a first normally closed contact of a grounding switch closing relay, which are connected in series with a grounding switch opening relay coil;

the grounding switch closing circuit also comprises a first normally closed contact of a grounding switch opening relay and a first normally closed contact of an isolating switch closing relay which are connected with a grounding switch closing relay coil in series;

the isolating switch opening loop further comprises a second normally closed contact of the grounding switch opening relay AY and a second normally closed contact of the isolating switch closing relay, wherein the second normally closed contact of the grounding switch opening relay AY and the second normally closed contact of the isolating switch closing relay are connected with the isolating switch opening relay coil in series;

the isolating switch closing circuit further comprises a second normally closed contact of the grounding switch closing relay and a second normally closed contact of the isolating switch opening relay, wherein the second normally closed contacts are connected with the isolating switch closing relay coil in series.

4. The three-position switch operating mechanism according to claim 3, further comprising a second micro switch and a holding loop for keeping the excitation branch disconnected, wherein the second micro switch comprises a first contact set, the first contact set comprises a first moving contact and two corresponding fixed contacts, and the first moving contact and one of the fixed contacts of the second micro switch are connected in series in the excitation branch;

the holding loop comprises a coil of a holding relay, one end of the coil of the holding relay is connected with the other fixed contact of the second microswitch, and the other end of the coil of the holding relay is connected between the coil of the excitation relay and the first branch circuit;

and a normally closed contact of the holding relay is connected in series with the exciting relay coil, and a normally open contact of the holding relay is connected in series with the holding relay coil and used for continuously electrifying the holding relay coil.

5. The three-position switch operating mechanism of claim 3, further comprising a third microswitch for switching between manual and electrical control, the third microswitch comprising two pairs of normally closed contacts; the grounding switch opening loop and the grounding switch closing loop are connected in parallel and then connected in series with one pair of normally closed contacts of the third microswitch, and the isolating switch opening loop and the isolating switch closing loop are connected in parallel and then connected in series with the other pair of normally closed contacts of the third microswitch; when the crank is inserted into the corresponding crank hole of the three-position switch operating mechanism, the normally closed contact of the third microswitch is triggered to be disconnected.

6. The three-station switch operating mechanism according to claim 2, wherein the forward rotation control branch comprises a forward rotation contactor coil, a second normally open contact of the grounding switch closing relay and a second normally open contact of the isolating switch opening relay, and the second normally open contact of the grounding switch closing relay and the second normally open contact of the isolating switch opening relay are connected in parallel and then are connected in series with the forward rotation contactor;

the reverse control branch circuit comprises a reverse contactor coil, a second normally open contact of the grounding switch opening relay and a second normally open contact of the isolating switch closing relay, and the second normally open contact of the grounding switch opening relay and the second normally open contact of the isolating switch closing relay are connected in parallel and then connected with the reverse contactor in series.

7. The three-position switch operating mechanism according to claim 6, wherein the motor drive circuit comprises a first normally open contact of a forward contactor, a motor rotor winding, a second normally open contact of the forward contactor, a motor stator winding and a third normally open contact of the forward contactor which are sequentially connected in series;

still include the first normally open contact of reversal contactor, reversal contactor second normally open contact and reversal contactor third normally open contact, the first normally open contact of reversal contactor is parallelly connected with the first normally open contact of corotation contactor, and reversal contactor second normally open contact is parallelly connected at the both ends behind corotation contactor second normally open contact and the motor stator winding series connection, and reversal contactor third normally open contact is parallelly connected at the both ends behind motor stator winding and the corotation contactor third normally open contact series connection.

8. The three-position switch operating mechanism according to claim 6, further comprising a fourth normally open contact of the reverse contactor connected in parallel with the ground switch opening command input, a fifth normally open contact of the reverse contactor connected in parallel with the disconnecting switch closing command input, a fourth normally open contact of the forward contactor connected in parallel with the ground switch closing command input, and a fourth normally open contact of the forward contactor connected in parallel with the disconnecting switch opening command input.

9. The three-position switch operating mechanism according to claim 6, further comprising a motor brake control loop, wherein the motor brake control loop comprises a two-position relay coil, a first coil of the two-position relay coil is connected with a sixth normally open contact of the forward contactor, and a second coil of the two-position relay coil is connected with a sixth normally open contact of the reverse contactor;

the motor driving circuit also comprises a first single-pole double-throw switch and a second single-pole double-throw switch, wherein a moving contact of the first single-pole double-throw switch is connected between a first normally open contact of the forward contactor and a motor rotor winding after being connected with a first normally closed contact of the forward contactor and a first normally closed contact of the reverse contactor in series; a first fixed contact of the first single-pole double-throw switch is connected with a second fixed contact of the second single-pole double-throw switch and then connected between a second normally open contact of the forward rotation contactor and a motor stator winding, and a second fixed contact of the first single-pole double-throw switch is connected with a first fixed contact of the second single-pole double-throw switch and then connected between the motor stator winding and a third normally open contact of the forward rotation contactor;

when a first coil of the double-position relay coil is electrified, a moving contact of a first single-pole double-throw switch is closed with a first fixed contact of the first single-pole double-throw switch, and a moving contact of a second single-pole double-throw switch is closed with the first fixed contact of the second single-pole double-throw switch;

when the second coil of the double-position relay coil is electrified, the moving contact of the first single-pole double-throw switch is closed with the second fixed contact of the first single-pole double-throw switch, and the moving contact of the second single-pole double-throw switch is closed with the second fixed contact of the second single-pole double-throw switch.

10. The three-position switch operating mechanism of claim 1, further comprising a detection circuit for detecting an operating state of the three-position switch, the detection circuit comprising a second set of contacts of a second microswitch;

the second contact group is connected with the grounding switch opening signal detection interface through a third normally open contact of the grounding switch opening relay, the second contact group is connected with the grounding switch closing signal detection interface through a third normally open contact of the grounding switch closing relay, the second contact group is connected with the isolating switch opening signal detection interface through a third normally open contact of the isolating switch opening relay, and the second contact group is connected with the isolating switch closing signal detection interface through a third normally open contact of the isolating switch closing relay.

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