CN2796199Y - Unattended online monitoring comprehensive automatic control cabinet - Google Patents

Abstract

Unattended on-line monitoring integrated automatic control cabinet, which is composed of a screen cabinet and an AC power supply circuit, a DC power supply circuit and a protection control circuit arranged in the screen cabinet. The AC power supply circuit is led from the low-voltage side of the main transformer through the used transformer and leads to a total AC 380V power supply. , the AC power supply is controlled by an AC contactor and equipped with AC 380V fan power supply, rectifier power supply and multi-channel AC 220V power supply. The main point of the secondary star connection is that the rectified and filtered output of the DC power supply circuit is equipped with multiple 220V DC power supplies. In the multi-channel 220V DC power supply, two energy storage circuits composed of super capacitor charging and discharging circuits are configured. Two energy storage circuits The capacitors in the battery are all super capacitors. The two super capacitors are charged and work at the same time, but they are independent of each other. The damage of each capacitor will not affect the normal operation of the other capacitor. The utility model has the advantages of convenient installation and maintenance, small volume, movable, small investment and reliable operation.

Description

Unattended online monitoring integrated automation control cabinet

(1) Technical field

The utility model relates to a control cabinet, in particular to a control cabinet in which the AC and DC systems, holding devices and automatic devices in a substation are integrated into a control cabinet occupying an area less than one meter square, which can replace the main control position of the substation and can Unattended online monitoring integrated automation control cabinet that moves according to the needs of the power supply location.

(2) Background technology

At present, substations in remote areas of our country are generally equipped with only one 66KV4MVA main transformer, and the secondary distribution lines are protected by lead wires. With the rapid growth of the national economy, the power consumption in these areas has also increased rapidly. As the load continues to increase, it is necessary to replace the 66KV4MVA main transformer with a 10MVA main transformer to meet the power demand. According to regulations, it is not allowed to use lead wire protection for such a large transformer. It is necessary to install a switch and configure the relay protection of the operating switch and Automatic device, which requires a new main control room in the substation, but there are many problems in the new main control room, for example, there is no place to build the main control room in the substation or emergency temporary power, it is too late to build the main control room, or build the main control room High cost, uneconomical and other issues. If the new substation is not built, the main control functions of the substation must be concentrated in an integrated control cabinet, so that the assembled integrated control cabinet can be installed nearby according to the needs of the site. This inevitably requires that each device has a simple principle, simplified wiring, and adapts to harsh outdoor weather conditions. For protection devices, conventional inductive or electromagnetic relays are used, which are not affected by power loss and weather conditions. There is mature field experience in this area, and the technical index for telecontrol devices is -40°C-50°C The product, once the AC power is lost, can use the internal battery to work, and can also adapt. Therefore, whether the integrated control cabinet can function reliably depends on how to solve the DC system. The storage battery has a large capacity and a long power consumption time. It is a reliable DC power supply, but it requires complex charging systems, monitoring systems and temperature control measures. It is unrealistic to install these complex systems in the integrated control cabinet. The only possibility is It adopts diode full-wave rectification and electrolytic capacitor energy storage. When the electrical equipment fails, the electrolytic capacitor discharges to operate the switch. But once the electrolytic capacitor is discharged, the electric energy stored inside will disappear quickly, and its own self-discharge also reduces its ability to store electric energy.

(3) Contents of the invention

In order to solve the problems existing in the above-mentioned prior art, the utility model provides an unattended on-line monitoring integrated automation control cabinet, which can replace the main control position of the substation, and integrate the AC and DC systems, protection devices and automatic devices in the substation. In a cabinet.

The technical solution adopted:

The integrated automatic control cabinet for unattended online monitoring is composed of a screen cabinet and an AC power supply circuit, a DC power supply circuit and a protection control circuit arranged in the screen cabinet. The AC power supply circuit is controlled by the main power supply control switch through the low-voltage side of the main transformer through the used transformer, and is controlled by the main power control switch. Multi-channel AC 220V power supply is allocated to be used as switching heating power supply, test power supply, remote control power supply and heating source in the panel cabinet; the DC power supply circuit adopts traditional three-phase full-wave rectification, π filter, and rectification changes primary angle Connection, secondary star connection, so that the DC waveform is better. It is characterized in that the rectified and filtered output of the DC power supply circuit is equipped with four 220V DC power supplies, one for the control circuit other than tripping and closing, the second is for protection and tripping operation energy storage DC, and the third is for closing operation Energy storage direct current; the fourth circuit breaker energy storage motor direct current, in the four 220V DC power supplies distributed by the DC power supply circuit, configure two energy storage circuits, the second energy storage circuit is a capacitor charging and discharging circuit, and the two energy storage circuits The capacitors in the energy loop are all super capacitors. The two supercapacitors charge and work at the same time, but they are independent of each other. The damage of each capacitor will not affect the normal operation of the other capacitor.

The utility model is suitable for a substation with a single main transformer below 66KV/16MVA and a 220KV energy storage switch. It is especially suitable for remote mountainous areas where the secondary distribution outlets of the main transformer are protected by lead wires. Especially for emergency power consumption and temporary power consumption, this cabinet can be used to replace the main control room because it is too late or uneconomical to build the main control room. The biggest feature of this utility model is that super capacitors are used as energy storage components, instead of batteries with relatively complicated charging system, monitoring system and temperature control measures, so as to solve the problem of energy storage in the DC system, and further realize the miniaturization of the control cabinet At the same time, it can also save a lot of investment. The DC system of this control cabinet adopts three-phase full-wave rectification to charge two super capacitors. When the AC power source is lost, the electric energy stored in the capacitor can be used to Solve the protection, logic circuit action and switch operation. When a fault occurs, the protection device can reliably remove the fault. When the power supply is restored, it can be closed remotely or locally, and it can also ensure reliable tripping when it is closed at the fault point. And ensure that the circuit breaker motor is supplemented with energy storage for 1-4 times. As for the protection device, due to the selection of conventional inductive or electromagnetic relays, and the use of products with a technical index of -40°C-50°C for the telecontrol device, it can adapt to harsh outdoor weather conditions. The utility model has the advantages of convenient installation and maintenance, small volume, movable, small investment and reliable operation.

(4) Description of drawings

Fig. 1 is the front view of the utility model screen cabinet.

Fig. 2 is a rear view of the utility model screen cabinet.

(5) Specific implementation methods

The integrated automatic control cabinet for unattended online monitoring of the utility model includes a screen cabinet 1 and an AC power supply circuit, a DC power supply circuit and a protection control circuit arranged in the screen cabinet 1 . The screen cabinet 1 adopts a frame structure with a height of 1.8 meters, a width of 1 meter, and a thickness of 0.8 meters, and is packed with an insulating board so that the temperature in the cabinet is not affected too much by the outside world. The screen cabinet 1 has doors on both sides, which is convenient for maintenance. If it is not opened normally, the alarm signal of someone stealing the cabinet can be sent through the remote control device YD. The upper part of the front of the screen cabinet 1 is equipped with a rectifier device and a remote control device YD, and the middle is a protection device, including intermediate relays BCJ, ZJ, TBJ, overcurrent relays 1-3LJ, current relays, 4LJ, time relays 1-3SJ, Voltage relays YJ1 and YJ2, signal relays 1-5XJ, closing indicator light HD and operation switch KK. Below is the switch piece 1-3LP and the terminal button 1-8DN. The upper row on the back of the screen cabinet 1 is a temperature relay t, a contactor JCK, a micro switch 1-3WK, a phase failure relay DXJ, DXJ'. The second row is the automatic switch 1-13ZK, the third row is two supercapacitors C ₉ and C ₁₀ ; the bottom of the screen cabinet 1 is the rectifier transformer B, the heater R and the reset relay tJ, and the left side of the screen cabinet 1 is AC terminal block 1D; on the right are 4 fuses 1-4RD and DC terminal block 2D. Several horizontal pull straps are arranged on both sides of the screen cabinet 1 to facilitate cable fixing.

The AC power supply circuit is controlled by the main power control switch 1ZK installed on the panel cabinet 1 through the low-voltage side of the main transformer leading an AC 380V power supply through the used transformer. Each phase is equipped with a switching piece QP. During normal operation, the device uses the internal transformer to supply power. The 1-4QP switching piece is connected upward. When the main transformer is powered off and the temporary power supply is used, the 1-4QP switching piece is connected upward. The main switch of the temporary power supply is 4ZK , the temporary power supply can be accessed on the terminal button under the front of the cabinet. 1-4QP should be restored to its original position before power transmission. 2ZK is for controlling AC phase failure and contactor switch. During normal operation, such as AC phase loss, even if the contactor JCK disconnects the air-cooled power supply after the phase loss relay DXJ operates. The normally closed contact of the phase failure relay DXJ′ is connected in series with the AC contactor JCK and then connected to zero. The three-phase power supply controlled by 2ZK is equipped with capacitors CA, CB, and CC respectively. In order to prevent the AC 380V power supply derived from the used transformer from being cut off, a three-phase temporary power supply is configured, which is controlled by the power control switch 4ZK. Each of the three-phase and neutral lines is equipped with a switching piece 1-4QP. During normal operation, the middle terminal is connected to the upper terminal. When a temporary power source is used during a power failure, the middle terminal of the switching piece QP is connected to the lower terminal. Configure a three-phase rectifier power supply, controlled by 3ZK; configure a telecontrol device working power supply, controlled by 11ZK; configure a switch heating power supply, controlled by 8ZK; configure a single-phase test power supply, controlled by 10ZK. When the substation is powered off, the maintenance test personnel should disconnect 3ZK when they bring a gasoline generator to charge the device, and connect the output terminal of the generator to the generator input terminal button of the device after the voltage is adjusted by a single-phase voltage regulator. , close the automatic switch 12ZK, the DC voltage should be 220V. After the charging current drops to zero, you can disconnect 12ZK and stop the generator. Configure a temperature control circuit of one screen cabinet 1, controlled by 13ZK, and the heater R is connected to the circuit controlled by the temperature relay t and the temperature reset relay tJ.

The DC power supply circuit adopts the traditional three-phase full-wave rectification and π-type filter. The rectification transformer B adopts 2KVA, and the first delta connection and the second star connection make the DC waveform better. The rectification transformer B has 5 taps at a time, which is applicable Under different voltage conditions, ensure that the DC output is 220V. Connect a voltmeter V and a load resistor RFZ at the output end of the rectifier power supply, and connect an ammeter A in series. Two energy storage circuits are configured in the middle. Among the distributed DC circuits: the first circuit is a rectified DC circuit, and its DC output terminal is KM±. This circuit will be powered off when the AC is lost, and it is controlled by the DC control fuse 1RD without energy storage. It is used for control circuits other than tripping or closing; the second circuit is energy storage DC for protection and tripping operations, and the positive and negative poles of its DC output terminals are 1KM ⁺ and 2KM ^- respectively; this circuit consists of two forward-conducting diodes D ₇ , D ₈ and micro switch 1WK are connected in series, wherein diode D ₇ is connected in parallel with resistor R ₇ and capacitor C ₇ connected in series. Diode D ₈ is connected in parallel with resistor R ₈ and capacitor C ₈ connected in series; the third route is composed of two forward conducting diodes D ₉ , D ₁₀ and micro switch 1WK connected in series, wherein diode D ₉ is connected in series with resistor R ₉ and capacitor C ₉ are connected in parallel, and diode D ₁₀ is connected in parallel with series connected resistor R ₁₀ and capacitor C ₁₀ ; A problem in the closing circuit affects the tripping circuit; the fourth circuit is the DC of the energy storage motor of the circuit breaker, which is drawn out after the positive poles of the diodes D ₈ and D ₁₀ are connected, and the positive and negative poles of the DC output terminals are HM ⁺ and KM ^- respectively. . After the AC power source is lost, the power supply is not interrupted, and the power is supplied by the energy storage circuit. The energy storage circuit is composed of two capacitor charging and discharging circuits. The positive pole of a routing capacitor _C9 is connected to the negative pole of the diode D7 in the DC circuit through the fuse 5RD, the current limiting resistor RB1, the micro switch 2WK, the diode _D11 and the micro switch _3WK , and the negative pole of the capacitor _C9 is connected to the DC circuit Negative electrode KM ^- , the two ends of diode D ₁₁ are connected in parallel with a charging resistor RC1, and the two ends of charging resistor RC1 are connected in parallel with voltage relay YJ1. The anode of another routing capacitor _C10 is connected to the anode of the diode D10 in the third circuit via fuse 6KD, current limiting resistor RB2, microswitch 2WK, diode _D12 and microswitch _2WK , and the cathode of capacitor _C10 is connected to DC The negative electrode KM ^- of the loop and the two ends of the diode D ₁₂ are connected in parallel with the charging resistor RB ₂ , and meanwhile are connected in parallel with the voltage relay YJ2. In the two energy storage circuits, the capacitors C ₉ and C ₁₀ are super capacitors, and the two super capacitors C ₉ and C ₁₀ are charged at the same time and work at the same time, but they are independent of each other, and the damage of each capacitor will not affect the other. The working condition of a capacitor is realized by diodes D ₇ -D ₁₀ . The current-limiting resistors RB1 and RB2 in the two capacitor charging and discharging circuits can prevent the diodes from burning out due to too much short-circuit current when the DC system fails. The selection of diodes D ₁₁ and D ₁₂ should ensure that they will not burn out when they pass a large current in the forward direction. In order to prevent the leakage of capacitors C ₉ and C ₁₀ in the energy storage circuit when the DC power supply is lost, there is no long-term excitation in the energy storage DC circuit relay. Charging resistors RC1 and RC2 use 1KW electric furnace wire to straighten the electric furnace wire to prevent heating, which not only meets the charging requirements of super capacitors, but also prevents the charging resistor from heating and disconnecting. The selection of DC fuses has a ladder nature. When the load side is short-circuited, 1-4RD will be fused accordingly, but the protection of super capacitors C ₉ and C ₁₀ will be disconnected. Corresponding fuse. When the supercapacitor _C9 or _C10 is broken down, the corresponding protective capacitor breakers 5RD and 6RD are not fused. Therefore, during normal charging, the voltage drop on the charging resistors RC1 and RC2 changes from large to small, and finally is zero. When the capacitor breaks down, its voltage is constant. According to this feature, in the protection control circuit, a time relay 3SJ is started after the contacts of the voltage relay YJ1 and YJ2 are connected in parallel. The delay contact of relay 3SJ activates the micro switch 2WK or 3WK through YJ1 or YJ2 to cut off the faulty capacitor and prevent long-term charging of the faulty capacitor. At the same time, the 2WK or 3WK linkage contact sends out the electrolytic breakdown signal through the remote control device, which is convenient for timely processing. Configuring two voltage relays YJ1 and YJ2 can solve two problems. One is that when the capacitor breaks down, the voltage relay starts 3SJ to cut off the faulty capacitor after a delay. The other is that the charging resistor is disconnected. A relay can work instead of a charging resistor.

When the circuit breaker moves in case of a fault, in order to prevent the tripping circuit from releasing energy for a long time, use the circuit breaker changeover contact DL and the normally open contact of the anti-jump relay TBJ to connect in series, and then the overrunning time relay 2SJ, as long as the switch does not move, the 2SJ contact cannot connected. 2SJ can be set for 0.2 seconds, start the 1WK micro switch, and 1WK will disconnect the energy storage power supply of the tripping and closing circuit. After the maintenance personnel handle the switch, manually close the 1WK micro switch to open and close the circuit breaker. If 1WK is not closed, the circuit breaker cannot be closed. When the circuit breaker refuses to move, the additional contact of 1WK will send a switch abnormal signal through the remote control device.

Please refer to Figure 3. The protection control circuit is a known technology and does not provide protection content, so its configuration is briefly described as follows:

1. Equipped with three 1-3LJ over-current relays, DC action tripping, the relays have instantaneous action and delayed action contacts, which start different signals respectively, so as to distinguish between internal and external faults of the main transformer.

2. Equipped with heavy gas protection, it acts on tripping through the middle of the outlet.

3. Equipped with light gas protection, acting on the signal.

4. Lead out the over-temperature contact of the main transformer to act on the signal.

5. Configure the low-voltage protection on the low-voltage side of the main transformer to act on the signal.

6. Configure the system grounding protection on the low-voltage side of the main transformer to act on the signal.

7. Configure the main transformer overload protection, after a delay, it acts on the signal.

8. Configure the AC and DC disconnection function to act on the signal.

9. Reflect switch abnormalities such as: SF6 pressure is low, when the switch energy storage starts, the spring does not store energy, the switch cabinet moves, and acts on the signal.

10. Equipped with operating switch KK, which is normally switched to a remote position. When the switch needs to be operated nearby, this switch can be used for opening and closing.

11. Configure the switch closing monitoring light HD.

12. The signal relay 1-15KJ adopts the drop sign to indicate that it can clearly indicate the fault situation when the system loses power, and adopts the manual reset method.

13. Except for the inverse time limit overcurrent, the relays are all plug-in, which is easy to replace.

14. When the automatic switch or fuse installed in the screen cabinet 1 fails or is blown, there will be a drop-off indication, which creates conditions for sending a warning signal for any abnormality in the device.

The first row on the front of the screen cabinet 1 is equipped with a telecontrol device, and its function is as follows:

1. Telemetry function, remote control device check In the case of no high-voltage side PT installed, the current, voltage, active power, reactive power, power factor, etc. of each distribution circuit are collected through the watt-hour meter, and transmitted to the centralized control station remotely.

2. With the remote control function, you can switch on and off at a distance by using mobile phone and wireless communication.

3. Remote signaling function and power management.

Claims (2)

1. Unattended on-line monitoring integrated automatic control cabinet is composed of a screen cabinet (1) and an AC power supply circuit, a DC power supply circuit and a protection control circuit arranged in the screen cabinet (1). The AC power supply circuit is composed of the main transformer One AC 380V main power supply on the low-voltage side is controlled by the main power supply control switch through the used transformer. The AC power supply is controlled by the AC contactor and equipped with AC 380V fan power supply and rectifier power supply. As a switching heating power supply, a test power supply, a telecontrol power supply and a heating source in the screen cabinet (1); the DC power supply circuit adopts a traditional three-phase full-wave rectification, π-type filter, and the rectification becomes a delta connection at the first stage, and a star connection at the second stage. , to make the DC waveform better, and its features are: the rectified and filtered output of the DC power supply circuit is equipped with multiple 220V DC power supplies, and among the multiple 220V DC power supplies, two energy storage circuits composed of super capacitor charging and discharging circuits are configured. The capacitors in the two energy storage circuits are supercapacitors. The two supercapacitors are charged and work at the same time, but they are independent of each other. The damage of each capacitor will not affect the normal operation of the other capacitor. 2. The integrated automatic control cabinet for unattended online monitoring according to claim 1, characterized in that the rectified and filtered output end of the DC power supply circuit is equipped with four 220V DC power supplies, one for control other than tripping and closing The circuit is used, the second circuit is for protection and tripping operation energy storage direct current, the circuit is composed of two forward conduction diodes D ₇ , D ₈ and micro switch 1WK connected in series, diode D ₇ is connected in parallel with the resistance connected in series R ₇ and filter capacitor C ₇ , diode D ₈ are connected in parallel with resistor R ₈ and filter capacitor C ₈ connected in series; the third circuit is the energy storage DC for closing operation, and the DC circuit consists of two forward-conducting diodes D ₉ , D ₁₀ and micro switch 1WK are connected in series, diode D ₉ is connected in parallel with resistance R ₉ and filter capacitor C ₉ connected in series, and diode D ₁₀ is connected in parallel with resistance R ₁₀ and filter capacitor C ₁₀ connected in series; the fourth The circuit breaker energy storage direct current; of the two energy storage circuits, one is connected to the positive electrode of the capacitor C ₉ through the fuse RD, the current limiting resistor RB1, the micro switch 2WK, the diode D ₁₁ and the micro switch 3WK and the diode in the DC circuit. The negative pole of D ₇ is connected, the negative pole of capacitor C ₉ is connected to the negative pole KM- of the DC circuit, the two ends of diode D ₁₁ are connected with a charging resistor RC1, and the two ends of charging resistor RC1 are connected with voltage relay YJ1; the other route is capacitor C The anode of ₁₀ is connected to the anode of diode D 10 in the third circuit via fuse 6KD, current limiting resistor RB2, micro switch 2WK, diode D ₁₂ and micro switch 2WK, and the negative pole of capacitor _{C 10 is} connected to the negative pole KM of the DC circuit ^- , Both ends of the diode D ₁₂ are connected in parallel with a charging resistor RB ₂ , and a voltage relay YJ2 is also connected in parallel.

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