A distribution network control device and method

Abstract

The present invention provides a distribution network control device and method, the control device and method include a circuit breaker, a double-side voltage detection unit, a current detection unit, an input-output unit, a digital-to-analog conversion component, a central processing unit, a controller and an input-output unit, wherein the circuit breaker is connected to the double-side voltage detection unit, the current detection unit, the input-output unit and the controller, the double-side voltage detection unit and the current detection unit are respectively connected to the digital-to-analog conversion component, the digital-to-analog conversion component is connected to the central processing unit, the central processing unit is connected to the input-output unit and the input-output unit, the input-output unit is connected to the controller, the control device and method automatically judge the distribution network fault, isolate the fault area and control the distribution network to self-heal. The advantages of the distribution network control device are: it does not rely on communication, quickly, accurately and reliably completes the automatic isolation of various distribution network faults and automatic power supply to non-fault areas.

Description

Technical Field

[0001] The present invention relates to a control device and method, in particular to a distribution network control device and method, belonging to the technical field of relay protection and automation of power system distribution network. Background Art

[0002] Smart grids are reliable, high-quality, efficient, compatible, and interactive. They are the development direction of modern power grids and have received great attention from the power industry at home and abroad. In recent years, summarizing the lessons learned from several major power outages in the world, domestic and foreign experts and companies have conducted a lot of research on improving the self-healing ability of large-scale transmission networks and thus improving the safety and stability of power grids, and have achieved a series of research results. However, the existing technology has little development and research on the self-healing ability of distribution networks.

[0003] my country's distribution network generally adopts a neutral point low current grounding method. After a single-phase grounding fault, there is no obvious short-circuit current, but the voltage of the non-fault phase increases, and the fault section is difficult to identify and quickly isolate. There is a huge threat to people and equipment near the grounding point. For a long time, due to the failure to quickly and effectively isolate single-phase grounding faults, personal electric shock accidents have occurred from time to time, especially electric shock casualties of social personnel. The distribution network is directly facing the user, and its short-circuit and grounding fault isolation and self-healing capabilities will directly affect the power supply quality of the power grid to users. Circuit breakers are important equipment in the distribution network. By controlling the circuit breakers, the distribution network fault isolation and self-healing can be achieved.

[0004] In summary, it is necessary to provide a distribution network control device and method that can overcome the defects of the prior art. Summary of the invention

[0005] The present invention aims to provide a distribution network control device and method, which can overcome the defects of the prior art. The purpose of the present invention is achieved through the following technical solutions.

[0006] One embodiment of the present invention provides a distribution network control device, wherein the control device includes a circuit breaker, a double-sided voltage detection unit, a current detection unit, an input / output unit, a digital-to-analog conversion component, a central processing unit, a controller and an input / output unit, the controller includes a closing control component, wherein the circuit breaker is connected to the double-sided voltage detection unit, the current detection unit, the input / output unit and the controller, the double-sided voltage detection unit and the current detection unit are respectively connected to the digital-to-analog conversion component, the digital-to-analog conversion component is connected to the central processing unit, the central processing unit is connected to the input / output unit and the input / output unit, the input / output unit is connected to the controller, the double-sided voltage detection unit is used to detect the respective phase voltages and respective zero-sequence voltages on three lines at both ends of the circuit breaker, the current detection unit is used to detect the respective phase currents and zero-sequence currents on the three lines passing through the circuit breaker, the input / output unit is used to detect the position contacts of the circuit breaker and transmit the signal of the central processing unit to the controller, and the closing control component is used to control the closing of the circuit breaker after charging.

[0007] According to the distribution network control device provided by one embodiment of the present invention, the control device comprises:

[0008] The double-side voltage detection unit detects the voltages UA, UB, UC, 3UO at both ends of the circuit breaker and transmits the detection results to the central processor through the digital-to-analog conversion component, the current detection unit detects the currents IA, IB, IC and transmits the detection results to the central processor through the digital-to-analog conversion component, and the input and output unit detects the switch position state of the circuit breaker and transmits the detection results to the central processor;

[0009] The central processor determines whether the voltages UA, UB, and UC on both sides of the circuit breaker are equal. If so, the central processor controls the charging of the closing control component through the input and output unit; and

[0010] The central processor determines whether the switch position state of the circuit breaker is in the "closed" position. If so, the central processor performs the section circuit breaker monitoring / self-healing process; if not, the central processor performs the connecting circuit breaker self-healing process.

[0011] According to the distribution network control device provided by one embodiment of the present invention, the section circuit breaker monitoring / self-healing process includes:

[0012] The double-side voltage detection unit detects the voltages UA, UB, UC, 3UO at both ends of the circuit breaker and transmits the detection results to the central processor through the digital-to-analog conversion component. The current detection unit detects the currents IA, IB, IC, 3IO and transmits the detection results to the central processor through the digital-to-analog conversion component.

[0013] The central processor determines whether a single-phase grounding fault occurs according to 3UO and 3I0 of the circuit breaker. If so, the central processor controls the circuit breaker to delay tripping through the input and output unit and the controller; if not, it determines whether a three-phase symmetrical fault occurs according to IA, IB, and IC of the circuit breaker. If so, the central processor controls the circuit breaker to delay tripping through the input and output unit and the controller; if not, the central processor determines whether a two-phase asymmetrical fault occurs according to IA, IB, and IC of the circuit breaker. If so, the central processor controls the circuit breaker to delay tripping through the input and output unit and the controller; if not, the central processor determines whether the three-phase voltage loss condition is met according to UA, UB, UC, and 3UO at both ends of the circuit breaker. If so, the central processor controls the circuit breaker to delay tripping through the input and output unit and the controller;

[0014] The double-side voltage detection unit detects the voltages UA, UB, UC, 3UO at both ends of the circuit breaker and transmits the detection results to the central processor through the digital-to-analog conversion component;

[0015] The central processor determines whether there is voltage on one side of the circuit breaker. If so, the central processor determines whether the voltage is an instantaneous residual voltage. If so, the closing controller discharges, and the input and output unit outputs the locking closing information; if not, the central processor controls the circuit breaker to delay closing through the input and output unit and the controller; and,

[0016] The circuit breaker determines whether it is closed in a fault state. If so, the circuit breaker accelerates tripping, the closing controller discharges, and the input and output unit outputs the locking closing information.

[0017] According to the distribution network control device provided by one embodiment of the present invention, the tie circuit breaker self-healing process includes:

[0018] The double-side voltage detection unit detects the voltages UA, UB, UC, 3UO at both ends of the circuit breaker and transmits the detection results to the central processor through the digital-to-analog conversion component;

[0019] The central processing unit determines whether there is no pressure on one side of the circuit breaker. If so, the central processing unit determines whether the preset self-healing delay time has been reached;

[0020] The central processor determines whether the preset self-healing delay time has been reached. If so, the central processor controls the circuit breaker to close through the input and output unit and the controller; if not, the double-side voltage detection unit detects the voltage UA, UB, UC, 3UO on the non-voltage side of the circuit breaker and transmits the detection result to the central processor through the digital-to-analog conversion component;

[0021] The central processing unit determines whether there is pressure on the no-pressure side. If so, the closing controller discharges and the input-output unit outputs the locking closing information.

[0022] According to the distribution network control device provided by the above-mentioned one embodiment of the present invention, the central processor determines whether the voltages UA, UB, and UC on both sides of the circuit breaker are equal. If not, the input-output unit reports an error.

[0023] According to the distribution network control device provided by one of the above embodiments of the present invention, the distribution network control device also includes starting the "successive fast action" and "weak feed protection" functions after a two-phase asymmetric fault occurs, and whether the "successive fast action" and "weak feed protection" functions are effective is set by the input and output unit. The "successive fast action" function is used to accelerate the isolation of the faulty distribution network, and the "weak feed protection" function is used to instantaneously trip the opposite side of the fault point when a fault occurs near the outlet on the power supply side of the distribution network line. While the faulty power supply side continues to sense the fault, it senses the change in electrical quantity again and accelerates the tripping.

[0024] According to the distribution network control device provided by the above-mentioned one embodiment of the present invention, the circuit breaker delayed tripping includes pre-setting different delay times according to different installation locations of the circuit breaker and fault types.

[0025] According to the distribution network control device provided by the above one embodiment of the present invention, the circuit breaker delayed closing includes pre-setting different delay times according to the line material, arc extinguishing time and user nature.

[0026] An embodiment of the present invention provides a distribution network control method, wherein the control method comprises multiple steps:

[0027] Step 1: Detect the voltages UA, UB, UC, 3UO at both ends of the circuit breaker, detect the currents IA, IB, IC and detect the switch position status of the circuit breaker;

[0028] Step 2: Determine whether the voltages UA, UB, and UC on both sides of the circuit breaker are equal. If so, charge and then execute step 3; and

[0029] Step 3: Determine whether the switch position status is in the "closed" position. If so, perform section circuit breaker monitoring / self-healing processing; if not, perform interconnection circuit breaker self-healing processing.

[0030] According to the distribution network control method provided by one embodiment of the present invention, the section circuit breaker monitoring / self-healing process comprises multiple steps:

[0031] Step 4: Detect the voltages UA, UB, UC, 3UO and currents IA, IB, IC, 3IO at both ends of the circuit breaker;

[0032] Step 5: Determine whether a single-phase grounding fault occurs according to 3UO and 3I0 of the circuit breaker. If so, proceed to step 6; if not, determine whether a three-phase symmetrical fault occurs according to IA, IB, and IC of the circuit breaker. If so, proceed to step 6; if not, determine whether a two-phase asymmetrical fault occurs according to IA, IB, and IC of the circuit breaker. If so, proceed to step 6; if not, determine whether a three-phase voltage loss condition is met according to UA, UB, UC, and 3UO at both ends of the circuit breaker. If so, proceed to step 6; if not, proceed to step 4;

[0033] Step 6: Circuit breaker tripping with time delay;

[0034] Step 7: Detect the voltages UA, UB, UC, 3UO across the circuit breaker;

[0035] Step 8: Determine whether there is pressure on one side of the circuit breaker. If so, go to step 9; if not, go to step 7;

[0036] Step 9: Determine whether the voltage is an instantaneous residual voltage. If so, discharge and output the lockout closing information; if not, delay closing of the circuit breaker, and then execute step 10; and,

[0037] Step 10: Determine whether the circuit breaker is closed in a fault state. If so, accelerate tripping, discharge, and output lock-close information; if not, execute step 1.

[0038] According to the distribution network control method provided by one embodiment of the present invention, the tie circuit breaker self-healing process comprises multiple steps:

[0039] Step 12: Detect the voltages UA, UB, UC, 3UO across the circuit breaker;

[0040] Step 13: Determine whether there is no pressure on one side of the circuit breaker. If so, go to step 14; if not, go to step 12;

[0041] Step 14: Determine whether the preset self-healing delay time has been reached. If so, close the circuit breaker and then execute step 1; if not, detect the voltage UA, UB, UC, 3UO on the non-voltage side of the circuit breaker and then execute step 15; and,

[0042] Step 15: Determine whether there is pressure on the no-pressure side. If so, discharge, output the lock-close information, and then execute step 1; if not, execute step 14.

[0043] According to the distribution network control method provided by the above one embodiment of the present invention, the step 2 is: judging whether the voltages UA, UB, and UC on both sides of the circuit breaker are equal, and if not, reporting an error.

[0044] According to the distribution network control method provided by one of the above embodiments of the present invention, the distribution network control method also includes starting the "successive quick action" and "weak feed protection" functions after a two-phase asymmetric fault occurs, and whether the "successive quick action" and "weak feed protection" functions are effective is set by the input and output unit. The "successive quick action" function is used to accelerate the isolation of the faulty distribution network, and the "weak feed protection" function is used for instantaneous tripping of the opposite side of the fault point when a fault occurs near the outlet on the power supply side of the distribution network line. While the faulty power supply side continues to sense the fault, it senses the change in electrical quantity again and accelerates the tripping.

[0045] According to the distribution network control method provided by the above-mentioned one embodiment of the present invention, the circuit breaker delayed tripping includes pre-setting different delay times according to different installation locations of the circuit breaker and fault types.

[0046] According to the distribution network control method provided by the above one embodiment of the present invention, the circuit breaker delayed closing includes pre-setting different delay times according to the line material, arc extinguishing time and user nature.

[0047] The advantages of the distribution network control device are: it does not rely on communication, does not rely on the coordination of the 10kV line outlet protection and reclosing switch of the substation, does not rely on secondary reclosing, and the power grid will not suffer from multiple fault shocks; it can take into account the requirements of "selectivity" and "rapidity" at the same time; it can automatically identify whether the distribution network switch belongs to "segmentation" or "communication", and automatically put into the corresponding function; it can adapt to the "normal" and "abnormal" operation modes of the distribution network, and the functions can be put into normal operation in both "normal" and "abnormal" modes; the integrated design meets different application scenarios such as distribution network fault isolation, self-healing and user intelligent demarcation; the overall design of the device is simple, the reliability is high, plug and play, easy to maintain without power outage, and easy to promote. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The disclosure of the present invention will become easier to understand with reference to the accompanying drawings. It is easy for those skilled in the art to understand that these drawings are only used to illustrate the technical solution of the present invention and are not intended to limit the scope of protection of the present invention. In the drawings:

[0049] Figure 1 A block diagram of a distribution network control device according to an embodiment of the present invention is shown.

[0050] Figure 2 A flow chart of a distribution network control method according to an embodiment of the present invention is shown.

[0051] Figure 3 It shows that Figure 2 The figure shows a flow chart of section circuit breaker monitoring / self-healing processing of a distribution network control method according to an embodiment of the present invention.

[0052] Figure 4 It shows that Figure 2 The figure shows a flow chart of the self-healing process of the tie circuit breaker of the distribution network control method according to one embodiment of the present invention. DETAILED DESCRIPTION

[0053] Figure 1-4 The following description describes the optional embodiments of the present invention to teach those skilled in the art how to implement and reproduce the present invention. In order to teach the technical solution of the present invention, some conventional aspects have been simplified or omitted. Those skilled in the art will understand that variations or replacements derived from these embodiments will fall within the scope of protection of the present invention. Those skilled in the art will understand that the following features can be combined in various ways to form multiple variations of the present invention. Thus, the present invention is not limited to the following optional embodiments, but is only limited by the claims and their equivalents.

[0054] Figure 1 A distribution network control device according to an embodiment of the present invention is shown, wherein the control device includes a circuit breaker 1, a double-side voltage detection unit 2, a current detection unit 3, an input / output unit 4, a digital-to-analog conversion component 5, a central processing unit 6, a controller 7 and an input / output unit 8, wherein the controller 7 includes a closing control component, wherein the circuit breaker 1 is connected to the double-side voltage detection unit 2, the current detection unit 3, the input / output unit 4 and the controller 7, the double-side voltage detection unit 2 and the current detection unit 3 are respectively connected to the digital-to-analog conversion component 5, the digital-to-analog conversion component 5 is connected to the central processing unit 6, the central processing unit 6 is connected to the input / output unit 4 and the input / output unit 8, the input / output unit 4 is connected to the controller 7, the double-side voltage detection unit 2 is used to detect the respective phase voltages and zero-sequence voltages on the three lines at both ends of the circuit breaker 1, the current detection unit 3 is used to detect the respective phase currents and zero-sequence currents on the three lines passing through the circuit breaker 1, the input / output unit 4 is used to detect the position contacts of the circuit breaker 1 and transmit the signal of the central processing unit 6 to the controller 7, and the closing control component is used to control the closing of the circuit breaker 1 after charging.

[0055] According to the distribution network control device provided by one embodiment of the present invention, the control device comprises:

[0056] The double-side voltage detection unit 2 detects the voltages UA, UB, UC, 3UO at both ends of the circuit breaker 1 and transmits the detection results to the central processor 6 through the digital-to-analog conversion component 5, the current detection unit 3 detects the currents IA, IB, IC and transmits the detection results to the central processor 6 through the digital-to-analog conversion component 5, and the input and output unit 4 detects the switch position state of the circuit breaker 1 and transmits the detection results to the central processor 6;

[0057] The central processor 6 determines whether the voltages UA, UB, and UC on both sides of the circuit breaker 1 are equal. If so, the central processor 6 controls the closing control component to charge through the input and output unit 4; and

[0058] The central processor 6 determines whether the switch position state of the circuit breaker 1 is in the "closed" position. If so, the central processor 6 performs monitoring / self-healing processing of the section circuit breaker 1; if not, the central processor 6 performs self-healing processing of the connecting circuit breaker 1.

[0059] According to the distribution network control device provided by one embodiment of the present invention, the monitoring / self-healing process of the section circuit breaker 1 includes:

[0060] The double-side voltage detection unit 2 detects the voltages UA, UB, UC, 3UO at both ends of the circuit breaker 1 and transmits the detection results to the central processor 6 through the digital-to-analog conversion component 5. The current detection unit 3 detects the currents IA, IB, IC, 3IO and transmits the detection results to the central processor 6 through the digital-to-analog conversion component 5.

[0061] The central processor 6 determines whether a single-phase grounding fault occurs according to 3UO and 3I0 of the circuit breaker 1. If so, the central processor 6 controls the circuit breaker 1 to delay tripping through the input and output unit 4 and the controller 7; if not, it determines whether a three-phase symmetrical fault occurs according to IA, IB, and IC of the circuit breaker 1. If so, the central processor 6 controls the circuit breaker 1 to delay tripping through the input and output unit 4 and the controller 7; if not, the central processor 6 determines whether a two-phase asymmetrical fault occurs according to IA, IB, and IC of the circuit breaker 1. If so, the central processor 6 controls the circuit breaker 1 to delay tripping through the input and output unit 4 and the controller 7; if not, the central processor 6 determines whether a three-phase voltage loss condition is met according to UA, UB, UC, and 3UO at both ends of the circuit breaker 1. If so, the central processor 6 controls the circuit breaker 1 to delay tripping through the input and output unit 4 and the controller 7;

[0062] The double-side voltage detection unit 2 detects the voltages UA, UB, UC, 3UO at both ends of the circuit breaker 1 and transmits the detection results to the central processor 6 through the digital-to-analog conversion component 5;

[0063] The central processor 6 determines whether there is voltage on one side of the circuit breaker 1. If so, the central processor 6 determines whether the voltage is an instantaneous residual voltage. If so, the closing controller 7 discharges, and the input and output unit 8 outputs the locking closing information; if not, the central processor 6 controls the circuit breaker 1 to delay closing through the input and output unit 4 and the controller 7; and,

[0064] The circuit breaker 1 determines whether it is closed in a fault state. If so, the circuit breaker 1 accelerates to trip, the closing controller 7 discharges, and the input-output unit 8 outputs the locking closing information.

[0065] According to the distribution network control device provided by one embodiment of the present invention, the self-healing process of the tie circuit breaker 1 includes:

[0066] The double-side voltage detection unit 2 detects the voltages UA, UB, UC, 3UO at both ends of the circuit breaker 1 and transmits the detection results to the central processor 6 through the digital-to-analog conversion component 5;

[0067] The central processor 6 determines whether there is no pressure on one side of the circuit breaker 1. If so, the central processor 6 determines whether the preset self-healing delay time has been reached;

[0068] The central processor 6 determines whether the preset self-healing delay time has been reached. If so, the central processor 6 controls the circuit breaker 1 to close through the input and output unit 4 and the controller 7; if not, the double-side voltage detection unit 2 detects the voltages UA, UB, UC, 3UO on the non-voltage side of the circuit breaker 1 and transmits the detection results to the central processor 6 through the digital-to-analog conversion component 5;

[0069] The central processing unit 6 determines whether there is pressure on the non-pressure side. If so, the closing controller 7 discharges and the input-output unit 8 outputs the locking closing information.

[0070] According to the distribution network control device provided by the above-mentioned one embodiment of the present invention, the central processor 6 determines whether the voltages UA, UB, and UC on both sides of the circuit breaker 1 are equal. If not, the input-output unit 8 reports an error.

[0071] According to the distribution network control device provided by the above-mentioned one embodiment of the present invention, the distribution network control device also starts the "successive fast action" and "weak feed protection" functions after a two-phase asymmetric fault occurs, and the input and output unit 8 has a switch for controlling whether the "successive fast action" and "weak feed protection" functions are effective. Whether to start the "successive fast action" and "weak feed protection" functions is set by turning on / off the switch. The "successive fast action" function is used to accelerate the isolation of the faulty distribution network, and the "weak feed protection" function is used for instantaneous tripping of the opposite side of the fault point when a fault occurs near the outlet on the power supply side of the distribution network line. While the faulty power supply side continues to sense the fault, it senses the change in electrical quantity again and accelerates the tripping.

[0072] According to the distribution network control device provided by one embodiment of the present invention, the circuit breaker delayed tripping includes pre-setting different delay times according to the installation position of the circuit breaker and the fault type, such as 0 to 0.3 seconds or longer for a three-phase symmetrical fault, 0 to 0.6S or longer for a two-phase asymmetrical fault, and single-phase fault does not need to consider coordination with the main grid and can be set from 10S or longer.

[0073] According to the distribution network control device provided by the above-mentioned one embodiment of the present invention, the circuit breaker delayed closing includes pre-setting different delay times, such as 1 to 3 seconds or longer, according to factors such as power line material, arc extinguishing time, user nature, etc.

[0074] Figure 2A flow chart of a distribution network control method according to an embodiment of the present invention is shown, wherein the control device controls the distribution network including multiple steps:

[0075] Step 100: Detecting voltages UA, UB, UC, 3UO across the circuit breaker, detecting currents IA, IB, IC, and detecting a switch position state of the circuit breaker;

[0076] Step 101: Determine whether the voltages UA, UB, and UC on both sides of the circuit breaker are equal. If so, execute step 102;

[0077] Step 102: Charging; and,

[0078] Step 103: Determine whether the switch position state of the circuit breaker is in the "closed" position. If so, execute the section circuit breaker monitoring / self-healing process 104; if not, execute the connecting circuit breaker self-healing process 105.

[0079] According to the distribution network control device provided by the above embodiment of the present invention, the step 101: determining whether the voltages UA, UB, and UC on both sides of the circuit breaker are equal, if not, executing step 106;

[0080] Step 106: Report an error.

[0081] Figure 3 It shows that Figure 2 The flow chart of the section circuit breaker monitoring / self-healing process of the distribution network control device and method according to one embodiment of the present invention is shown, wherein the section circuit breaker monitoring / self-healing process 104 includes multiple steps:

[0082] Step 200: Detect the voltages UA, UB, UC, 3UO and the currents IA, IB, IC, 3IO at both ends of the circuit breaker;

[0083] Step 201: Determine whether a single-phase grounding fault occurs according to circuit breakers 3U0 and 3I0. If yes, execute step 205; if no, execute step 202;

[0084] Step 202: Determine whether a three-phase symmetrical fault occurs according to IA, IB, and IC of the circuit breaker. If so, execute step 205; if not, execute step 203;

[0085] Step 203: Determine whether a two-phase asymmetric fault occurs according to IA, IB, and IC of the circuit breaker. If so, execute step 205; if not, execute step 204;

[0086] Step 204: Determine whether the three-phase voltage loss condition is met according to UA, UB, UC, and 3UO of the circuit breaker. If so, execute step 205; if not, execute step 200;

[0087] Step 205: Delayed tripping of the circuit breaker;

[0088] Step 206: Detect the voltages UA, UB, UC, 3UO across the circuit breaker;

[0089] Step 207: Determine whether there is pressure on one side of the circuit breaker. If so, execute step 208; if not, execute step 206;

[0090] Step 208: Determine whether the voltage is an instantaneous residual voltage. If so, execute step 212; if not, execute step 209;

[0091] Step 209: Delay closing of the circuit breaker;

[0092] Step 210: Determine whether the circuit breaker is closed in a fault state. If so, execute step 211; if not, execute step 100;

[0093] Step 211: Circuit breaker accelerated tripping; and,

[0094] Step 212: Discharge and output lockout closing information.

[0095] Figure 4 It shows that Figure 2 The figure shows a flow chart of the tie breaker self-healing process of the distribution network control device and method according to one embodiment of the present invention, wherein the tie breaker self-healing process 105 includes multiple steps:

[0096] Step 300: Detect the voltages UA, UB, UC, 3UO across the circuit breaker;

[0097] Step 301: Determine whether there is no pressure on one side of the circuit breaker. If so, execute step 302; if not, execute step 300;

[0098] Step 302: Determine whether the preset self-healing delay time has been reached, if so, execute step 303; if not, execute step 304;

[0099] Step 303: the circuit breaker is closed, and then step 100 is executed;

[0100] Step 304: Detect the voltages UA, UB, UC, 3UO on the non-voltage side of the circuit breaker;

[0101] Step 305: Determine whether there is pressure on the non-pressure side. If so, execute step 306; if not, execute step 302; and

[0102] Step 306: Discharge, output lockout closing information, and then execute step 1.

[0103] According to the distribution network control device provided by one of the above embodiments of the present invention, the distribution network control device also includes starting the "successive fast action" and "weak feed protection" functions after a two-phase asymmetric fault occurs, and whether the "successive fast action" and "weak feed protection" functions are effective is set by the input and output unit. The "successive fast action" function is used to accelerate the isolation of the faulty distribution network, and the "weak feed protection" function is used to instantaneously trip the opposite side of the fault point when a fault occurs near the outlet on the power supply side of the distribution network line. While the faulty power supply side continues to sense the fault, it senses the change in electrical quantity again and accelerates the tripping.

[0104] According to the distribution network control device provided by one embodiment of the present invention, the circuit breaker delayed tripping includes pre-setting different delay times according to the installation position of the circuit breaker and the fault type, such as 0 to 0.3 seconds or longer for a three-phase symmetrical fault, 0 to 0.6S or longer for a two-phase asymmetrical fault, and single-phase fault does not need to consider coordination with the main grid and can be set from 10S or longer.

[0105] According to the distribution network control device provided by the above-mentioned one embodiment of the present invention, the circuit breaker delayed closing includes pre-setting different delay times, such as 1 to 3 seconds or longer, according to factors such as power line material, arc extinguishing time, user nature, etc.

[0106] The advantages of the distribution network control device are: it does not rely on communication, does not rely on the coordination of the 10kV line outlet protection and reclosing switch of the substation, does not rely on secondary reclosing, and the power grid will not suffer from multiple fault shocks; it can take into account the requirements of "selectivity" and "rapidity" at the same time; it can automatically identify whether the distribution network switch belongs to "segmentation" or "communication", and automatically put into the corresponding function; it can adapt to the "normal" and "abnormal" operation modes of the distribution network, and the functions can be put into normal operation in both "normal" and "abnormal" modes; the integrated design meets different application scenarios such as distribution network fault isolation, self-healing and user intelligent demarcation; the overall design of the device is simple, reliable, plug-and-play, easy to maintain, no power outage required, and easy to promote.

[0107] It should be appreciated that although the foregoing description has been made by way of example of the present invention, such and other modifications and changes to the present invention that will be apparent to those skilled in the art should be considered to fall within the broad scope of the present invention as set forth herein. Therefore, although the present invention has been described with reference to preferred embodiments, it is not intended that the novel device be limited thereby, but rather that it is intended to include various modifications and equivalent modifications within the broad scope of the above disclosure and claims.

Claims

1. A distribution network control device, characterized in that: The control device comprises a circuit breaker, a double-side voltage detection unit, a current detection unit, an input / output unit, a digital-to-analog conversion component, a central processing unit, a controller and an input / output unit, wherein the controller comprises a closing control component, wherein the circuit breaker is connected to the double-side voltage detection unit, the current detection unit, the input / output unit and the controller, the double-side voltage detection unit and the current detection unit are respectively connected to the digital-to-analog conversion component, the digital-to-analog conversion component is connected to the central processing unit, the central processing unit is connected to the input / output unit and the input / output unit, the input / output unit is connected to the controller, the double-side voltage detection unit is used to detect the respective phase voltages and respective zero-sequence voltages on the three wires at both ends of the circuit breaker, the current detection unit is used to detect the respective phase currents and zero-sequence currents on the three wires passing through the circuit breaker, the input / output unit is used to detect the position contacts of the circuit breaker and transmit the signal of the central processing unit to the controller, and the closing control component is used to control the closing of the circuit breaker after charging; The double-side voltage detection unit detects the voltages UA, UB, UC, 3UO at both ends of the circuit breaker and transmits the detection results to the central processor through the digital-to-analog conversion component, the current detection unit detects the currents IA, IB, IC and transmits the detection results to the central processor through the digital-to-analog conversion component, and the input and output unit detects the switch position state of the circuit breaker and transmits the detection results to the central processor; The central processor determines whether the voltages UA, UB, and UC on both sides of the circuit breaker are equal. If so, the central processor controls the charging of the closing control component through the input and output unit; and the central processor determines whether the switch position state of the circuit breaker is in the "closed" position. If so, the central processor performs the section circuit breaker monitoring / self-healing processing; if not, the central processor performs the connecting circuit breaker self-healing processing; The section circuit breaker monitoring / self-healing process includes: The double-side voltage detection unit detects the voltages UA, UB, UC, 3UO at both ends of the circuit breaker and transmits the detection results to the central processor through the digital-to-analog conversion component. The current detection unit detects the currents IA, IB, IC, 3IO and transmits the detection results to the central processor through the digital-to-analog conversion component. The central processor determines whether a single-phase grounding fault occurs according to 3UO and 3I0 of the circuit breaker. If so, the central processor controls the circuit breaker to delay tripping through the input and output unit and the controller; if not, it determines whether a three-phase symmetrical fault occurs according to IA, IB, and IC of the circuit breaker. If so, the central processor controls the circuit breaker to delay tripping through the input and output unit and the controller; if not, the central processor determines whether a two-phase asymmetrical fault occurs according to IA, IB, and IC of the circuit breaker. If so, the central processor controls the circuit breaker to delay tripping through the input and output unit and the controller; if not, the central processor determines whether the three-phase voltage loss condition is met according to UA, UB, UC, and 3UO at both ends of the circuit breaker. If so, the central processor controls the circuit breaker to delay tripping through the input and output unit and the controller; The double-side voltage detection unit detects the voltages UA, UB, UC, 3UO at both ends of the circuit breaker and transmits the detection results to the central processor through the digital-to-analog conversion component; The central processor determines whether there is voltage on one side of the circuit breaker. If so, the central processor determines whether the voltage is an instantaneous residual voltage. If so, the closing controller discharges, and the input-output unit outputs the blocking closing information; if not, the central processor controls the circuit breaker to delay closing through the input-output unit and the controller; and the circuit breaker determines whether it is closed in a fault state. If so, the circuit breaker accelerates tripping, the closing controller discharges, and the input-output unit outputs the blocking closing information; The tie circuit breaker self-healing process includes: The double-side voltage detection unit detects the voltages UA, UB, UC, 3UO at both ends of the circuit breaker and transmits the detection results to the central processor through the digital-to-analog conversion component; The central processor determines whether there is no pressure on one side of the circuit breaker. If so, the central processor determines whether the preset self-healing delay time has been reached; The central processor determines whether the preset self-healing delay time has been reached. If so, the central processor controls the circuit breaker to close through the input and output unit and the controller; if not, the double-side voltage detection unit detects the voltage UA, UB, UC, 3UO on the non-voltage side of the circuit breaker and transmits the detection result to the central processor through the digital-to-analog conversion component; The central processing unit determines whether there is pressure on the no-pressure side. If so, the closing controller discharges and the input-output unit outputs the locking closing information.

2. The distribution network control device according to claim 1, characterized in that: The central processing unit determines whether the voltages UA, UB, and UC on both sides of the circuit breaker are equal. If not, the input and output unit reports an error.

3. The distribution network control device according to claim 1, characterized in that: The distribution network control device also includes starting the "successive fast action" and "weak feed protection" functions after a two-phase asymmetric fault occurs. Whether the "successive fast action" and "weak feed protection" functions are effective is set by the input and output unit. The "successive fast action" function is used to accelerate the isolation of the faulty distribution network. The "weak feed protection" function is used to instantaneously trip the opposite side of the fault point when a fault occurs near the outlet on the power supply side of the distribution network line. While the faulty power supply side continues to sense the fault, it senses the change in electrical quantity again and accelerates the tripping.

4. The distribution network control device according to claim 3, characterized in that: The circuit breaker delayed tripping includes presetting different delay times according to different installation locations of the circuit breaker and fault types.

5. The distribution network control device according to claim 3, characterized in that: The circuit breaker delayed closing includes presetting different delay times according to different line materials, arc extinguishing time and user properties.

6. A distribution network control method, characterized in that: The control method comprises a plurality of steps: Step 1: Detect the voltages UA, UB, UC, 3UO at both ends of the circuit breaker, detect the currents IA, IB, IC and detect the switch position status of the circuit breaker; Step 2: Determine whether the voltages UA, UB, and UC on both sides of the circuit breaker are equal. If so, charge and then proceed to step 3; as well as Step 3: Determine whether the switch position is in the "closed" position. If so, perform the section circuit breaker monitoring / self-healing process; if not, perform the connecting circuit breaker self-healing process; Step 4: Detect the voltages UA, UB, UC, 3UO at both ends of the circuit breaker, and detect the currents IA, IB, IC, 3IO; Step 5: Determine whether a single-phase grounding fault occurs according to 3UO and 3I0 of the circuit breaker. If so, proceed to step 6; if not, determine whether a three-phase symmetrical fault occurs according to IA, IB, and IC of the circuit breaker. If so, proceed to step 6; if not, determine whether a two-phase asymmetrical fault occurs according to IA, IB, and IC of the circuit breaker. If so, proceed to step 6; if not, determine whether a three-phase voltage loss condition is met according to UA, UB, UC, and 3UO at both ends of the circuit breaker. If so, proceed to step 6; if not, proceed to step 4; Step 6: Circuit breaker tripping with time delay; Step 7: Detect the voltages UA, UB, UC, 3UO across the circuit breaker; Step 8: Determine whether there is pressure on one side of the circuit breaker. If so, go to step 9; if not, go to step 7; Step 9: Determine whether the voltage is an instantaneous residual voltage. If so, discharge and output the lockout closing information; if not, delay closing of the circuit breaker, and then execute step 10; and, Step 10: Determine whether the circuit breaker is closed in a fault state. If so, accelerate tripping, discharge, and output lock-close information; If not, go to step 1; Step 12: Detect the voltages UA, UB, UC, 3UO across the circuit breaker; Step 13: Determine whether there is no pressure on one side of the circuit breaker. If so, go to step 14; if not, go to step 12; Step 14: Determine whether the preset self-healing delay time has been reached. If so, close the circuit breaker and then execute step 1; if not, Detect the voltage UA, UB, UC, 3UO on the non-voltage side of the circuit breaker, and then execute step 15; and, Step 15: Determine whether there is pressure on the no-pressure side. If so, discharge, output the lock-close information, and then execute step 1; if not, execute step 14.

7. The distribution network control method according to claim 6, characterized in that: Step 2: determine whether the voltages UA , UB , and UC on both sides of the circuit breaker are equal, if not, report an error.

8. The distribution network control method according to claim 6, characterized in that: The distribution network control method also includes starting the "successive fast action" and "weak feed protection" functions after a two-phase asymmetric fault occurs. Whether the "successive fast action" and "weak feed protection" functions are effective is set by the input and output unit. The "successive fast action" function is used to accelerate the isolation of the faulty distribution network. The "weak feed protection" function is used to instantaneously trip the opposite side of the fault point when a fault occurs near the outlet on the power supply side of the distribution network line. While the faulty power supply side continues to sense the fault, it senses the change in electrical quantity again and accelerates the tripping.

9. The distribution network control method according to claim 8, characterized in that: The circuit breaker delayed tripping includes presetting different delay times according to different installation locations of the circuit breaker and fault types.

10. The distribution network control method according to claim 9, characterized in that: The circuit breaker delayed closing includes presetting different delay times according to different line materials, arc extinguishing time and user properties.

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