CN210693462U - Current-limiting type ring network controller - Google Patents

Abstract

A current-limiting ring network controller, the ring network controller is installed at the bus outlet on both sides of the ring network circuit, and includes: a reactor, a lightning arrester, a switch device and a control device; the reactor, the lightning arrester and the switch device Parallel connection; the control device is connected to the switchgear for collecting data of the ring network controller close to the load side, and controlling the switchgear to open and close according to the data close to the load side; the reactor is used to limit the loop closure Impulse current; the arrester is used for overvoltage protection of the ring network controller; the switchgear is used for switching on or bypassing the reactor and performing overcurrent protection. By installing the ring network controller of this scheme at the busbar outlet of the ring network circuit, it can be realized that when the ring network is repaired, the ring is closed first and then the ring is released. It solves the problem of power failure in the process of transferring line loads due to line maintenance and other reasons, and improves the reliability of power supply for important loads.

Description

A current-limiting ring network controller

technical field

The utility model relates to the field of live loop closure of a distribution network, in particular to a current-limiting type loop network controller.

Background technique

Power grid users have higher and higher requirements for power supply reliability, especially some industrial users are very sensitive to power outages, and short-term power outages may cause great economic losses. The voltage level of the distribution network is not limited to 10kV, but at least includes 6kV, 10kV, 20kV or 35kV. The medium and low voltage distribution network generally adopts the power supply mode of closed-loop design and open-loop operation. At present, in the case of load reversal and line maintenance, the steps of the parallel operation are generally to open the switch at the target disengagement position first, and then close the switch at the original disengagement position, that is, "open first and then close", this process will cause partial load power outage. If the non-power-off method of "closing first and then opening" is adopted, which is to close at the original ring-opening position (that is, perform the ring-closing operation first) and then open at the target ring-opening position, the number of power outages can be reduced and the reliability of power supply can be improved.

However, there is a greater risk if the uninterrupted power-off and solution operation is performed directly. The reason is that if the ring-closing operation is performed directly in the open-loop running distribution network, there are the following problems: due to the voltage difference between the two ends of the ring-closing point before the ring-closing, a large inrush current is usually generated during the ring-closing, and the There is a circulating current of the electromagnetic ring network behind the ring; the ring closing impact may also cause the malfunction of the relay protection of the distribution network, resulting in failure; and the on-site ring closing operation is judged under the experience and guidance of the operating personnel, and the ring closing operation There is a very high randomness in the results, which may cause hidden dangers to the safety of related equipment and operators.

Utility model content

In order to solve the problem in the prior art that the ring-closing impact occurs when the distribution network is closed, the utility model provides a current-limiting type ring network controller.

The technical scheme provided by the utility model is:

A current-limiting ring network controller, the ring network controller is installed at the outlet of the bus bars on both sides of the ring network circuit, comprising:

Reactors, arresters, switchgear and control equipment;

The reactor and the arrester are connected in parallel with the switchgear;

The control device is connected to the switchgear, and is used for collecting data of the ring network controller close to the load side, and controlling the switchgear to open and close according to the data close to the load side;

The reactor is used to limit the closed loop impulse current;

The arrester is used for overvoltage protection of the ring network controller;

The switchgear is used for switching on or bypassing the reactor and performing overcurrent protection;

The opening time of the switchgear should be less than 0.3s and the closing time should be less than 10ms.

Preferably, the power frequency operating current of the reactor should not be less than 50% of the current when the line is fully loaded;

The inductance of the reactor should be greater than the amount corresponding to the ratio of the maximum voltage difference between the busbars at both ends to the allowable circulating current value of the line;

The voltage withstand level between terminals of the reactor may be lower than the insulation level to ground.

Preferably, the reactor may be an iron-core reactor or an air-core reactor.

Preferably, the iron core saturation point current of the iron core reactor should not be less than the maximum steady-state current flowing in the ring network controller.

Preferably, the switchgear includes:

Mechanical switches and thyristors;

The mechanical switch, thyristor, reactor and arrester are connected in parallel with each other;

The mechanical switch and the thyristor are jointly connected with the control device;

The mechanical switch is used to switch on or bypass the reactor and the arrester, and is also used to realize overcurrent protection;

The thyristor is used to quickly bypass reactors and arresters.

Preferably, the thyristor should be able to withstand line short-circuit impulse current.

Preferably, the mechanical switch should be able to withstand line short-circuit impulse current, and the withstand voltage level between terminals of the mechanical switch may be lower than the insulation voltage level to ground.

Preferably, the control device includes:

Measurement module and control module;

the control module is connected with the mechanical switch and the thyristor;

The measurement module is connected with the control module, and is used for collecting the instantaneous voltage value and the instantaneous value of the current of the ring network controller near the load side, and formulating an opening command and a closing command.

Preferably, the reactor, the arrester, the thyristor, the mechanical switch, the measurement module and the control module are all fixedly installed at the bus outlet of the ring network circuit.

Preferably, the reactor, the arrester, the thyristor and the mechanical switch are fixedly installed at the bus outlet of the ring network circuit;

When the loop network circuit is closed or unlooped, the measurement module and the control module are connected with the reactor, the arrester, the thyristor and the mechanical switch as moving parts.

Preferably, when there is a switchgear at the bus outlet of the ring network circuit, the reactor, arrester, thyristor, mechanical switch, measurement module and control module can be installed as moving parts at the bus outlet of the ring network circuit .

Preferably, when the ring network circuit is a single ring network, the ring network controller is installed at the outlet of two bus bars of the single ring network, and a total of two ring network controllers are installed on the wiring lines of the single ring network;

When the ring network circuit is a double ring network, the ring network controller is installed at the outlet of the four bus bars of the double ring network, and a total of four ring network controllers are installed on the wiring lines of the double ring network;

When the ring network circuit is the N supply and one standby wiring distribution network, the ring network controller is installed at all the busbar outlets of the N supply one standby wiring distribution network, and N+1 is required to be installed in the N supply one standby wiring line. Taiwan ring network controller;

When the ring network circuit is an N-1 wiring distribution network, the ring network controller is installed at all the busbar outlets of the N-1 wiring distribution network, and a total of N ring network controllers need to be installed on the N-1 wiring line. .

Compared with the prior art, the beneficial effects of the present utility model are:

In the technical solution provided by the utility model, the ring network controller is installed at the busbar outlets on both sides of the ring network circuit, and includes: a reactor, a surge arrester, a switch device and a control device; the reactor, the surge arrester and the switch The devices are connected in parallel; the control device is connected to the switchgear, and is used to collect the data of the ring network controller near the load side, and control the opening and closing of the switchgear according to the data near the load side; the reactor is used for Limiting the closed loop impulse current; the arrester is used for overvoltage protection of the ring network controller; the switchgear is used for switching on or bypassing the reactor and performing overcurrent protection. By installing the ring network controller of this scheme at the busbar outlet of the ring network circuit, it can be realized that during the maintenance of the ring network, the ring is closed first and then the ring is released. , to solve the problem of power failure in the process of transferring line loads due to line maintenance and other reasons, and improve the reliability of power supply for important loads.

The ring network controller in this scheme has a simple structure, including only reactors, arresters, switchgear and control equipment, and has the advantages of small changes to the distribution network, low cost and simple operation principle.

Description of drawings

Fig. 1 is a kind of current limiting ring network controller structure effect diagram of the present invention;

2 is a schematic diagram of the installation of a current-limiting ring network controller of the present invention in a single ring network wiring;

3 is a schematic diagram of the installation of a current-limiting ring network controller in the double ring network wiring of the present invention;

4 is a schematic diagram of the installation of a current-limiting ring network controller in the N supply and one standby wiring of the present invention;

5 is a schematic diagram of the installation of a current-limiting ring network controller in the N-1 wiring of the present invention;

6 is a schematic diagram of the initial state of a current-limiting ring network controller of the present invention;

7 is a first implementation diagram of a current-limiting ring network controller of the present invention;

8 is a second implementation diagram of a current-limiting ring network controller of the present invention;

9 is a third implementation diagram of a current-limiting ring network controller of the present invention;

10 is a fourth implementation diagram of a current-limiting ring network controller of the present invention;

11 is a fifth implementation diagram of a current-limiting ring network controller of the present invention;

12 is a sixth implementation diagram of a current-limiting ring network controller of the present invention;

13 is a schematic diagram of a moving part of a current-limiting ring network controller of the present invention.

Detailed ways

In order to better understand the present utility model, the content of the present utility model will be further described below with reference to the accompanying drawings and examples of the description.

Example 1:

This embodiment provides a current-limiting ring network controller, and a structural effect diagram is shown in FIG. 1 .

The ring network controller device is composed of reactors, arresters, switch equipment and control equipment, wherein the control equipment includes a measurement module and a control module; the switch equipment includes mechanical switches and thyristors. Among them, the reactor is used to limit the closed loop current, the mechanical switch is used to switch on, bypass the reactor and realize overcurrent protection, the thyristor is used to quickly bypass the reactor, and the arrester device is used to limit the overvoltage at both ends of the thyristor during line faults. The measurement module in the control device is used to measure the instantaneous value of the voltage near the load side of the ring network controller and the instantaneous value of the current flowing through the ring network controller. The control module in the control equipment is used to calculate the active power, and the instantaneous value of the voltage near the load side of the ring network controller and the instantaneous value of the current flowing through the ring network controller are the input quantities; the voltage of the ring network controller near the load side is calculated. The effective value and the active power flowing through the ring network controller; take the set voltage threshold and power threshold (0) as the setting value; set the RMS value of the voltage near the load side of the ring network controller and the set voltage threshold, flow through The active power of the ring network controller is compared with 0, and according to the comparison result, it is judged whether to output a trigger signal to the thyristor, and whether to output a closing or opening signal to the mechanical switch.

The reactor can use iron core or air core reactor, its power frequency operating current should be greater than the current when the line is fully loaded and not less than 50% of the current when the line is fully loaded, and the inductance should be greater than the maximum voltage difference between the busbars at both ends divided by the allowable circulating current of the line. The amount corresponding to the ratio of the values, if an iron-core reactor is used, the iron-core saturation point current of the iron-core reactor should not be less than the maximum steady-state current flowing through the ring network controller, and between the reactor terminals The voltage withstand level may be less than its insulation level to ground.

The thyristor should be able to withstand the line short-circuit impulse current. If the thyristor operates fast enough or the withstand voltage level of the entire ring network controller is high, the arrester capacity can be greatly reduced.

The mechanical switch shall be able to withstand the short-circuit impulse current of the line, and the withstand voltage level between the ends of the mechanical switch can be lower than its insulation voltage level to the ground. And the opening time of the mechanical switch should ensure that the overcurrent protection of the fastest line in the line does not act. If the line has no overcurrent protection, the opening time should not be greater than 0.3s.

Example 2:

The present embodiment provides a control method for a current-limiting ring network controller, and the ring network controller can be used to assist in uninterrupted and uninterrupted operation, and the specific contents are as follows:

或

的瞬时值和电流

或

的瞬时值，如图6所示。不同工况下，装置动作逻辑如下：Install two-ring network controller in one ring network. Under normal circumstances, the mechanical switch in the two-ring network controller is closed, the thyristor is turned off, and the two-ring network controller continuously measures the voltage at its outlet.

or

The instantaneous value and current of

or

The instantaneous value of , as shown in Figure 6. Under different working conditions, the action logic of the device is as follows:

1. Turn on the reactor when limiting the closed loop current

或

的有效值大于设定的出口电压阈值，并且，有功功率从负荷侧流向母线侧，则动作逻辑为：机械开关分闸。detected: detected

or

The effective value of is greater than the set outlet voltage threshold, and the active power flows from the load side to the bus side, the action logic is: the mechanical switch is opened.

2. Exit the reactor when the low voltage/line is faulty:

或

的有效值小于设定的出口电压阈值，则动作逻辑为：触发晶闸管，晶闸管导通；机械开关合闸；detected

or

The effective value of the thyristor is less than the set outlet voltage threshold, the action logic is: trigger the thyristor, the thyristor is turned on; the mechanical switch is closed;

After passing the corresponding delay, the triggering of the thyristor is stopped, and the thyristor is turned off.

3. Exit the reactor normally:

或

的有效值一直大于设定的出口电压阈值，则动作逻辑为：机械开关合闸；If it is detected within a period of time (should be greater than the time used for general unification operation)

or

The rms value is always greater than the set outlet voltage threshold, the action logic is: mechanical switch closing;

A ring network controller is installed at both ends of a ring network. Under normal circumstances, the mechanical switches in the two ring network controllers are in the closed position, the thyristor is turned off, and the arrester is in an open circuit state, as shown in Figure 6. When the system is fault-free, the parallel operation is carried out. It is agreed that when the loop is closed, a loop closing impact from bus B to bus A will occur. As shown in Figure 7, the ring network controller B does not act, and the ring network controller A detects the exit. When the active power is less than 0, an opening command is issued to the mechanical switch. After the mechanical switch is opened, the reactor is put into current limiting, and the loop closing impact is successfully limited, as shown in Figure 8.

If the fault as shown in Figure 9 occurs after the reactor is switched on during the loop closing period, the voltage of the ring network controller A near the load side decreases rapidly and is lower than the set voltage threshold. At this time, the action process of ring network controller A is as follows:

The arrester action limits the voltage across the ring network controller, as shown in Figure 9.

Trigger the thyristor, and the thyristor is turned on, as shown in Figure 10.

The mechanical switch is closed as shown in Figure 11.

After passing the corresponding delay, stop triggering the thyristor, and the thyristor is turned off, as shown in Figure 12.

Example 3:

This embodiment provides an installation position and an installation method of a current-limiting ring network controller.

The installation position of the ring network controller is between the busbar outlet on both sides of the ring network and the first load. The ring network controller can be installed in some 6kV, 10kV or 35kV distribution networks with different wiring methods to realize uninterrupted and uninterrupted operation.

The schematic diagram of the installation of the ring network controller in the single ring network wiring is shown in Figure 2. It is installed between the bus bar on both sides of the single ring network and the first load. When a part of the load needs to be powered from substation A to substation B, it can be directly closed at the open-loop point in the single-ring network, and the ring network controller limits the current during the closing of the loop to assist the completion of the non-power-off and unwinding operation.

The schematic diagram of the installation of the ring network controller in the double ring network wiring is shown in Figure 3. It is installed between the four bus bars in the double ring network and the first load. When load 1 needs to be powered from substation A to substation C, it can be directly closed at the open-loop point 1 in the double-ring network, and the ring network controller assists and completes the solution operation. When load 1 needs to be powered from substation A to substation B, the load switch B between load 1 and substation B can be closed directly. After closing, substations A and B form a closed loop. If an impact occurs, the ring network The controller acts to limit the impact, and then the load switch A opens, and the load 1 transfers power to the B substation, and the operation ends.

The schematic diagram of the installation of the ring network controller in the N supply and one standby wiring is shown in Figure 4, which is installed between the N+1 busbar outlet and the first load. When a part of the load needs to be powered by the A substation to the standby substation, the normally open contact on the line between the A substation and the standby substation can be directly closed, and the ring network controller is assisted and the operation is completed.

The schematic diagram of the installation of the ring network controller in the N-1 wiring is shown in Figure 5, which is installed between the outgoing wires of the N bus bars and the first load. When a part of the load needs to be powered from substation A to substation B, the normally open contacts on the line between substation A and substation B can be directly closed, and the ring network controller assists and completes the solution operation.

When installing the ring network controller, the installation method in which the reactor, arrester, thyristor, mechanical switch, control module and measurement module are all fixedly installed at the busbar outlet can be adopted.

A part of reactors, arresters, thyristors, mechanical switches, control modules and measurement modules can also be fixedly installed at the busbar outlet. The remaining part is used as a movable part. When it is necessary to perform the unification operation, move it to the outlet of the bus bar and connect it with the fixed part for use.

If the original switch device at the outlet of the bus can be used for bypassing and enabling the bypass ring network controller, the entire ring network controller can be used as a mobile device, and the ring network controller can be moved to this position for use when necessary, as shown in the figure 13 shown.

Obviously, the described embodiments are some, but not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention.

As will be appreciated by those skilled in the art, the embodiments of the present application may be provided as a method, a system, or a computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the present application. It will be understood that each flow and/or block in the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to the processor of a general purpose computer, special purpose computer, embedded processor or other programmable data processing device to produce a machine such that the instructions executed by the processor of the computer or other programmable data processing device produce Means for implementing the functions specified in a flow or flow of a flowchart and/or a block or blocks of a block diagram.

These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory result in an article of manufacture comprising instruction means, the instructions The apparatus implements the functions specified in the flow or flow of the flowcharts and/or the block or blocks of the block diagrams.

These computer program instructions can also be loaded on a computer or other programmable data processing device to cause a series of operational steps to be performed on the computer or other programmable device to produce a computer-implemented process such that The instructions provide steps for implementing the functions specified in the flow or blocks of the flowcharts and/or the block or blocks of the block diagrams.

The above are only examples of the present utility model, and are not intended to limit the present utility model. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present utility model are included in the application pending approval. within the scope of the claims of the present invention.

Claims (12)

1. a current-limiting type ring network controller, is characterized in that, described ring network controller is installed at the bus bar outlet on both sides of ring network circuit, comprising: Reactors, arresters, switchgear and control equipment; The reactor and the arrester are connected in parallel with the switchgear; The control device is connected to the switchgear, and is used for collecting data of the ring network controller close to the load side, and controlling the switchgear to open and close according to the data close to the load side; The reactor is used to limit the closed loop impulse current; The arrester is used for overvoltage protection of the ring network controller; The switchgear is used for switching on or bypassing the reactor and performing overcurrent protection. 2. ring network controller as claimed in claim 1, is characterized in that, The power frequency operating current of the reactor should not be less than 50% of the current when the line is fully loaded; The inductance of the reactor should be greater than the amount corresponding to the ratio of the maximum voltage difference between the busbars at both ends to the allowable circulating current value of the line; The voltage withstand level between terminals of the reactor may be lower than the insulation level to ground. 3. ring network controller as claimed in claim 2, is characterized in that, The reactor may be an iron-core reactor or an air-core reactor. 4. ring network controller as claimed in claim 3, is characterized in that, The iron core saturation point current of the iron core reactor should not be less than the maximum steady-state current flowing through the ring network controller. 5. The ring network controller of claim 1, wherein the switchgear comprises: Mechanical switches and thyristors; The mechanical switch, thyristor, reactor and arrester are connected in parallel with each other; The mechanical switch and the thyristor are jointly connected with the control device; The mechanical switch is used to switch on or bypass the reactor and the arrester, and is also used to realize overcurrent protection; The thyristor is used to quickly bypass reactors and arresters. 6. ring network controller as claimed in claim 5, is characterized in that, The thyristor should be able to withstand line short-circuit impulse current. 7. ring network controller as claimed in claim 5, is characterized in that, The mechanical switch should be able to withstand line short-circuit impulse current, and the withstand voltage level between terminals of the mechanical switch may be lower than the insulation voltage level to ground. 8. The ring network controller according to claim 5, wherein the control device comprises: Measurement module and control module; the control module is connected with the mechanical switch and the thyristor; The measurement module is connected with the control module, and is used for collecting the instantaneous voltage value and the instantaneous value of the current of the ring network controller near the load side, and formulating an opening command and a closing command. 9. ring network controller as claimed in claim 8, is characterized in that, The reactor, the arrester, the thyristor, the mechanical switch, the measurement module and the control module are all fixedly installed at the busbar outlet of the ring network circuit. 10. The ring network controller of claim 8, wherein The reactor, the arrester, the thyristor and the mechanical switch are fixedly installed at the bus outlet of the ring network circuit; When the loop network circuit is closed or unlooped, the measurement module and the control module are connected with the reactor, the arrester, the thyristor and the mechanical switch as moving parts. 11. The ring network controller of claim 8, wherein When there is switchgear at the bus outlet of the ring network circuit, the reactor, arrester, thyristor, mechanical switch, measurement module and control module can be installed as moving parts at the bus outlet of the ring network circuit. 12. The ring network controller of claim 1, wherein, When the ring network circuit is a single ring network, the ring network controller is installed at the outlet of two bus bars of the single ring network, and a total of two ring network controllers are installed on the wiring lines of the single ring network; When the ring network circuit is a double ring network, the ring network controller is installed at the outlet of the four bus bars of the double ring network, and a total of four ring network controllers are installed on the wiring lines of the double ring network; When the ring network circuit is the N supply and one standby wiring distribution network, the ring network controller is installed at all the busbar outlets of the N supply one standby wiring distribution network, and N+1 is required to be installed in the N supply one standby wiring line. Taiwan ring network controller; When the ring network circuit is an N-1 wiring distribution network, the ring network controller is installed at all the busbar outlets of the N-1 wiring distribution network, and a total of N ring network controllers need to be installed on the N-1 wiring line. .

Images