A distribution network fault self-healing method and device based on master station and terminal protection collaboration

Abstract

The present invention discloses a distribution network fault self-healing method and device based on the coordination of master station and terminal protection. By receiving switch displacement information and protection action information sent by the distribution terminal when a fault occurs, the switches at both ends of the fault section are determined in combination with the network topology of the distribution network. According to the switch displacement information sent by the distribution terminal, the switches at both ends of the fault section are opened to isolate the power supply lines between the switches at both ends of the fault section. Then, in combination with the network topology of the distribution network, it is determined whether the switches at both ends of the fault section include a tie switch. When it is determined that the switches at both ends of the fault section do not include a tie switch, the tie switch is controlled to close to restore power supply to the non-fault section, thereby avoiding power loss in the non-fault section upstream of the fault point after the fault, reducing the scope of the fault power outage, and at the same time reducing the power supply recovery time downstream of the fault point, thereby improving power supply reliability.

Description

Technical Field

[0001] The present invention relates to the technical field of distribution network, and in particular to a distribution network fault self-healing method and device based on master station and terminal protection collaboration. Background Art

[0002] The distribution network is directly facing users, and its power supply reliability is directly related to the national economy and social stability. As users' requirements for power supply reliability continue to increase, power grid companies have spent a lot of manpower and material resources to improve the reliability of distribution network power supply. When a fault occurs, rapid isolation of the faulty section and rapid power supply restoration of the non-faulty section are effective means to improve power supply reliability.

[0003] At present, the existing distribution network fault self-healing method is that after the fault occurs, each terminal device sends the detected fault overcurrent information to the master station, and the master station derives the fault section based on the distribution network topology and overcurrent conditions. After determining the section, the master station sends a remote control command to complete the fault isolation and power supply restoration. However, when the distribution network topology is more complex, the existing distribution network fault self-healing method is prone to power outage in the non-fault section upstream of the fault point after the fault, resulting in a large range of fault power outages and a long fault handling time.

[0004] The information disclosed in this background technology section is only intended to deepen the understanding of the overall background technology of the present invention, and should not be regarded as acknowledging or suggesting in any form that the information constitutes the prior art known to those skilled in the art. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a distribution network fault self-healing method and device based on the coordination of master station and terminal protection, so as to avoid power loss in the non-fault section upstream of the fault point after the fault, reduce the scope of the fault power outage, and at the same time reduce the power supply recovery time downstream of the fault point, thereby improving power supply reliability.

[0006] In order to achieve the above object, the present invention provides a distribution network fault self-healing method based on master station and terminal protection collaboration, which is characterized by comprising:

[0007] Receive switch position change information and protection action information sent by the distribution terminal when a fault occurs;

[0008] Determine switches at both ends of the fault section according to the network topology of the distribution network and the switch displacement information and protection action information;

[0009] According to the switch displacement information, the switches at both ends of the fault section are opened to isolate the power supply lines between the switches at both ends of the fault section;

[0010] According to the network topology of the distribution network, determining whether the switches at both ends of the fault section include tie switches;

[0011] If the switches at both ends of the fault section do not include a connecting switch, the connecting switch is controlled to close to restore power supply to the non-fault section.

[0012] Preferably, the protection of the power distribution terminal adopts overcurrent protection.

[0013] Preferably, the switch position change information and protection action information include the switch position change information and protection action information sent by the first power distribution terminal;

[0014] The method of determining switches at both ends of the fault section according to the topological structure of the distribution network and the switch displacement information and protection action information includes:

[0015] According to the network topology of the distribution network and the switch position change information and protection action information sent by the first distribution terminal, it is determined that the first switch corresponding to the first distribution terminal and the second switch located downstream of the first switch are the switches at both ends of the fault section.

[0016] Preferably, the method of opening the switches at both ends of the fault section according to the switch displacement information and isolating the power supply lines between the switches at both ends of the fault section includes:

[0017] According to the switch position change information sent by the first power distribution terminal, the second switch located downstream of the first switch is controlled to trip, so that the switches at both ends of the fault section are opened, and the power supply line between the switches at both ends of the fault section is isolated.

[0018] Preferably, the protection of the power distribution terminal adopts longitudinal protection.

[0019] Preferably, the switch position change information and protection action information include the switch position change information and protection action information sent by the second power distribution terminal and the switch position change information and protection action information sent by the third power distribution terminal;

[0020] The method of determining switches at both ends of the fault section according to the topological structure of the distribution network and the switch displacement information and protection action information includes:

[0021] According to the switch change information and protection action information sent by the second distribution terminal and the switch change information and protection action information sent by the third distribution terminal, it is determined that the third switch corresponding to the second distribution terminal and the fourth switch corresponding to the third distribution terminal are the switches at both ends of the fault section.

[0022] Preferably, the method of opening the switches at both ends of the fault section according to the switch displacement information and isolating the power supply lines between the switches at both ends of the fault section includes:

[0023] According to the switch position change information sent by the second distribution terminal and the switch position change information sent by the third distribution terminal, confirm that the third switch corresponding to the second distribution terminal and the fourth switch corresponding to the third distribution terminal are in the open state, so that the switches at both ends of the fault section are opened, and the power supply lines between the switches at both ends of the fault section are isolated.

[0024] Another aspect of the present invention provides a distribution network fault self-healing device based on master station and terminal protection collaboration, comprising:

[0025] An information receiving module, used to receive switch position change information and protection action information sent by the power distribution terminal when a fault occurs;

[0026] A fault determination module is used to determine the switches at both ends of the fault section according to the network topology of the distribution network and the switch displacement information and protection action information;

[0027] A fault isolation module, used to open the switches at both ends of the fault section according to the switch displacement information sent by the power distribution terminal, and isolate the power supply line between the switches at both ends of the fault section;

[0028] A type judgment module, used to judge whether the switches at both ends of the fault section include tie switches according to the network topology of the distribution network;

[0029] The power supply recovery module is used to control the connecting switch to close and restore the power supply to the non-fault section if the switches at both ends of the fault section do not include a connecting switch.

[0030] Preferably, the protection of the power distribution terminal adopts overcurrent protection;

[0031] The information receiving module is specifically used to receive the switch position change information and protection action information sent by the first distribution terminal when a fault occurs;

[0032] The fault determination module is specifically used to determine that a first switch corresponding to the first distribution terminal and a second switch located downstream of the first switch are switches at both ends of the fault section according to the network topology of the distribution network and the switch displacement information and protection action information sent by the first distribution terminal;

[0033] The fault isolation module is specifically used to control the second switch located downstream of the first switch to trip according to the switch change information sent by the first distribution terminal, so as to open the switches at both ends of the fault section and isolate the power supply line between the switches at both ends of the fault section.

[0034] Preferably, the protection of the power distribution terminal adopts longitudinal protection;

[0035] The information receiving module is specifically used to receive the switch position change information and protection action information sent by the second distribution terminal and the switch position change information and protection action information sent by the third distribution terminal when a fault occurs;

[0036] The fault determination module is specifically used to determine that the third switch corresponding to the second power distribution terminal and the fourth switch corresponding to the third power distribution terminal are switches at both ends of the fault section according to the switch displacement information and protection action information sent by the second power distribution terminal and the switch displacement information and protection action information sent by the third power distribution terminal;

[0037] The fault isolation module is specifically used to confirm that the third switch corresponding to the second distribution terminal and the fourth switch corresponding to the third distribution terminal are in the open state based on the switch change information sent by the second distribution terminal and the switch change information sent by the third distribution terminal, so as to open the switches at both ends of the fault section and isolate the power supply line between the switches at both ends of the fault section.

[0038] The present invention has at least the following beneficial effects:

[0039] The present invention determines the switches at both ends of the fault section by receiving the switch displacement information and protection action information sent by the distribution terminal when the fault occurs, in combination with the network topology of the distribution network, and according to the switch displacement information sent by the distribution terminal, the switches at both ends of the fault section are opened to isolate the power supply lines between the switches at both ends of the fault section, and then in combination with the network topology of the distribution network, it is determined whether the switches at both ends of the fault section include a connecting switch. When it is determined that the switches at both ends of the fault section do not include a connecting switch, the connecting switch is controlled to close and the power supply to the non-fault section is restored, thereby avoiding power loss in the non-fault section upstream of the fault point after the fault, reducing the scope of the fault power outage, and at the same time reducing the power supply recovery time downstream of the fault point, thereby improving the power supply reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0041] Figure 1 It is a flow chart of a distribution network fault self-healing method based on master station and terminal protection collaboration in an embodiment of the present invention;

[0042] Figure 2 This is a schematic diagram of the structure of a power distribution network in an embodiment of the present invention;

[0043] Figure 3 It is a structural schematic diagram of a distribution network fault self-healing device based on master station and terminal protection collaboration in an embodiment of the present invention;

[0044] Figure 4 It is a structural diagram of a distribution network fault self-healing device based on master station and terminal protection collaboration in an embodiment of the present invention. DETAILED DESCRIPTION

[0045] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0046] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation method.

[0047] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0048] See also Figure 1 On the one hand, an embodiment of the present invention provides a distribution network fault self-healing method based on master station and terminal protection collaboration, including:

[0049] S110. Receive switch position change information and protection action information sent by the power distribution terminal when a fault occurs.

[0050] In an embodiment of the present invention, the distribution automation terminal (hereinafter referred to as the distribution terminal) of the distribution network power supply line has protection input. When a fault occurs, the protection of the distribution terminal that detects the fault is activated, and according to the different protection principles adopted, the distribution terminal that is judged as the fault section selectively trips the upstream switch of the fault location or the upstream / downstream switch of the fault location to cut off the fault, and sends the switch change information and protection action information to the distribution automation master station (hereinafter referred to as the distribution master station); while other distribution terminals that detect the fault are judged as non-fault sections, the protection returns, and the corresponding switches will not be tripped. It can be understood that the switch change information mainly refers to the information that the switch in the distribution network power supply line has a tripping action after the fault occurs. Among them, the switches in the distribution network power supply line include substation outlet switches and distribution automation switches, and the distribution automation switches can be divided into section switches on the main line, branch switches and boundary switches on the branch line, and contact switches.

[0051] S120. Determine switches at both ends of the fault section according to the topological structure of the distribution network, switch displacement information, and protection action information.

[0052] In an embodiment of the present invention, the distribution master station stores the network topology of the distribution network power supply line. By inspecting the distribution network power supply line based on the switch position change information and protection action information sent by the distribution terminal in the fault section, the switches corresponding to the distribution terminals at both ends of the fault section can be determined. Among them, the switches corresponding to the distribution terminals at both ends of the fault section refer to the switches corresponding to the upstream distribution terminal closest to the fault location and the switches corresponding to the downstream distribution terminal closest to the fault location. It can be understood that if the distribution terminal only sends the switch position change information and does not send the corresponding protection action information, the distribution master station will not determine that the switch corresponding to the distribution terminal is the switch corresponding to the upstream distribution terminal closest to the fault location or the switch corresponding to the downstream distribution terminal closest to the fault location. The distribution terminal must send the switch position change information and the protection action information at the same time to prevent misjudgment.

[0053] S130. According to the switch displacement information, the switches at both ends of the fault section are opened to isolate the power supply lines between the switches at both ends of the fault section.

[0054] In an embodiment of the present invention, by judging the switch position change information sent by the distribution terminal of the fault section, it can be confirmed whether the switch corresponding to the upstream distribution terminal closest to the fault location and the switch corresponding to the downstream distribution terminal closest to the fault location are in the open state, ensuring that the switches at both ends of the fault section are open, thereby isolating the power supply line between the switches at both ends of the fault section.

[0055] S140: According to the topological structure of the distribution network, determine whether the switches at both ends of the fault section include a tie switch.

[0056] In the embodiment of the present invention, in combination with the network topology of the distribution network, the types of switches at both ends of the fault section can be determined to determine whether a tie switch is included.

[0057] S150. If the switches at both ends of the fault section do not include a tie switch, the tie switch is controlled to close to restore power supply to the non-fault section.

[0058] In an embodiment of the present invention, after the types of switches at both ends of the fault section are determined, if the switches at both ends of the fault section include a connecting switch, that is, the switch corresponding to the downstream distribution terminal closest to the fault location is a connecting switch, then the upstream of the connecting switch is the fault section, and at this time the connecting switch does not need to be closed to restore power supply to the non-fault section; if the switches at both ends of the fault section do not include a connecting switch, that is, the switch corresponding to the downstream distribution terminal closest to the fault location is not a connecting switch, then the upstream of the connecting switch is the non-fault section, and at this time it is necessary to send a closing command to the connecting switch according to the fault recovery strategy. After receiving the closing command, the connecting switch executes the closing command in combination with the state that one side of itself has pressure and the other side has no pressure, closes the connecting switch, and completes the power supply restoration of the non-fault section.

[0059] From the above, it can be seen that the embodiment of the present invention determines the switches at both ends of the fault section by receiving the switch position change information and protection action information sent by the distribution terminal when the fault occurs, combined with the network topology of the distribution network, and according to the switch position change information sent by the distribution terminal, the switches at both ends of the fault section are opened to isolate the power supply lines between the switches at both ends of the fault section, and then combined with the network topology of the distribution network, it is determined whether the switches at both ends of the fault section include a connecting switch. When it is determined that the switches at both ends of the fault section do not include a connecting switch, the connecting switch is controlled to close and the power supply to the non-fault section is restored, thereby avoiding the power loss of the non-fault section upstream of the fault point after the fault, reducing the scope of the fault power outage, and at the same time reducing the power supply recovery time downstream of the fault point, thereby improving the power supply reliability.

[0060] It should be noted that the protection principles adopted by the distribution terminals of the distribution network power supply lines are different, mainly including the overcurrent protection principle and the longitudinal protection principle. When a fault is detected, the distribution terminal will selectively trip the upstream switch of the fault location or the upstream / downstream switch of the fault location by adopting different protection principles. Therefore, the specific processes of executing step S120 and step S130 are also different, which are described in detail below.

[0061] Optionally, in some embodiments of the present invention, the protection of the power distribution terminal adopts overcurrent protection, and the switch position change information and the protection action information include the switch position change information and the protection action information sent by the first power distribution terminal;

[0062] Step S120 includes:

[0063] According to the network topology of the distribution network and the switch position change information and protection action information sent by the first distribution terminal, it is determined that the first switch corresponding to the first distribution terminal and the second switch located downstream of the first switch are the switches at both ends of the fault section.

[0064] In the embodiment of the present invention, the protection of the distribution terminal adopts overcurrent protection. When a fault occurs, the protection of the distribution terminal located upstream of the fault position detects the occurrence of the fault and the protection is started. Among them, the delay of the first switch corresponding to the upstream distribution terminal closest to the fault position (hereinafter referred to as the first distribution terminal) is the shortest. After the delay is reached, the first distribution terminal trips the corresponding first switch to complete the fault removal; while the protection of other distribution terminals upstream of the first distribution terminal returns, and their corresponding switches will not trip; while the protection of the distribution terminal located downstream of the fault position does not detect the occurrence of the fault, the protection action is not started, and its corresponding switch will not trip either. Therefore, the switch displacement information and protection action information sent by the distribution terminal after the fault occurs and received by the distribution master station only include the switch displacement information and protection action information sent by the first distribution terminal. The first switch corresponding to the first distribution terminal is the switch corresponding to the upstream distribution terminal closest to the fault position. Combined with the network topology of the distribution network, the second switch located downstream of the first switch is found to be the switch corresponding to the downstream distribution terminal closest to the fault position. In a specific implementation, there may be a branch downstream of the first switch. In this case, the second switch downstream of the first switch includes a segment switch on the main line downstream of the first switch and a branch switch or a boundary switch on the branch line.

[0065] Furthermore, in the above embodiment, step S130 includes:

[0066] According to the switch position information sent by the first power distribution terminal, the second switch located downstream of the first switch is controlled to trip, so that the switches at both ends of the fault section are opened, and the power supply line between the switches at both ends of the fault section is isolated.

[0067] In the embodiment of the present invention, according to the switch displacement information sent by the first power distribution terminal, the first switch corresponding to the first power distribution terminal is already in the open state, and at this time, the open command is sent to the power distribution terminal corresponding to the second switch located downstream of the first switch. After receiving the open command, the power distribution terminal, in combination with its own power failure state, trips the second switch to open the switches at both ends of the fault section, thereby isolating the power supply line between the switches at both ends of the fault section and completing fault isolation. In specific implementation, if the second switch located downstream of the first switch is a tie switch, the second switch itself is already in the open state, and there is no need to trip it again.

[0068] In specific implementation, the overcurrent protection is specifically a three-stage current protection.

[0069] Optionally, in some other embodiments of the present invention, the protection of the distribution terminal adopts longitudinal protection, and the switch position change information and protection action information include the switch position change information and protection action information sent by the second distribution terminal and the switch position change information and protection action information sent by the third distribution terminal;

[0070] Step S120 includes:

[0071] According to the switch position change information and protection action information sent by the second distribution terminal and the switch position change information and protection action information sent by the third distribution terminal, the third switch corresponding to the second distribution terminal and the fourth switch corresponding to the third distribution terminal are determined to be the switches at both ends of the fault section.

[0072] In an embodiment of the present invention, the protection of the distribution terminal adopts longitudinal protection. When a fault occurs, the protection of the distribution terminals located upstream of the fault location detects the occurrence of the fault and the protection is started. Among them, the delay of the third switch corresponding to the upstream distribution terminal closest to the fault location (hereinafter referred to as the second distribution terminal) is the shortest. After the delay is reached, the second distribution terminal trips the corresponding third switch to complete the fault removal. Other distribution terminals upstream of the second distribution terminal are judged as non-fault sections, and the protection is returned, and their corresponding switches will not trip. At the same time, since the distribution terminals at both ends of the fault section can exchange information, the downstream distribution terminal closest to the fault location (hereinafter referred to as the third distribution terminal) will also start the protection action and trip the corresponding fourth switch. Therefore, the received switch position change information and protection action information sent by the distribution terminal after the fault occurs include the switch position change information and protection action information sent by the second distribution terminal and the switch position change information and protection action information sent by the third distribution terminal. The third switch corresponding to the second distribution terminal is the switch corresponding to the upstream distribution terminal closest to the fault location, and the fourth switch corresponding to the third distribution terminal is the switch corresponding to the downstream distribution terminal closest to the fault location. In specific implementation, there may be a branch downstream of the third switch. At this time, the fourth switch located downstream of the third switch includes a segment switch on the main line downstream of the third switch and a branch switch or a boundary switch on the branch line.

[0073] Furthermore, in the above embodiment, step S130 includes:

[0074] According to the switch position change information sent by the second distribution terminal and the switch position change information sent by the third distribution terminal, confirm that the third switch corresponding to the second distribution terminal and the fourth switch corresponding to the third distribution terminal are in the open state, so that the switches at both ends of the fault section are open, and the power supply lines between the switches at both ends of the fault section are isolated.

[0075] In the embodiment of the present invention, according to the switch position change information sent by the second power distribution terminal and the switch position change information sent by the third power distribution terminal, the third switch corresponding to the second power distribution terminal and the fourth switch corresponding to the third power distribution terminal are already in the open state, and at this time, it can be confirmed that the switches at both ends of the fault section are open, thereby isolating the power supply lines between the switches at both ends of the fault section and completing the fault isolation. In specific implementation, if the third switch corresponding to the second power distribution terminal or the fourth switch corresponding to the third power distribution terminal is in the closed state, an alarm prompt is sent and the process is switched to manual processing.

[0076] In specific implementation, the longitudinal protection is specifically current differential protection or longitudinal directional protection.

[0077] In order to further facilitate understanding of the technical solution provided by the embodiment of the present invention, the application of the distribution network fault self-healing method based on master station and terminal protection collaboration provided by the embodiment of the present invention in a specific scenario is explained below with reference to the accompanying drawings.

[0078] See also Figure 2 , a schematic diagram of the structure of the power supply line of the distribution network in the embodiment of the present invention. Among them, CB1 represents the outgoing line switch of the substation, FB1, FB2, and FB3 represent the section switches on the trunk line, FB11 and FB21 represent the branch switches on the branch line, and LB1 and LB2 represent the tie switches.

[0079] First, take the overcurrent protection of the power distribution terminal as an example to illustrate:

[0080] Assuming that a fault occurs at position f1, the distribution terminal protection corresponding to switch CB1 upstream of position f1 senses overcurrent, protection is activated, and switch CB1 is tripped; the distribution terminal protection corresponding to switch FB1 downstream of position f1 does not sense overcurrent, protection is not activated, and switch FB1 is not tripped. At this time, only the distribution terminal corresponding to switch CB1 sends switch position change information and protection action information to the distribution master station. After receiving, the distribution master station confirms that switch CB1 is the switch corresponding to the upstream distribution terminal closest to the fault position. Combined with the network topology of the distribution network, it is determined that switch FB1 located downstream of switch CB1 is the switch corresponding to the downstream distribution terminal closest to the fault position. Since switch CB1 is already in the open state and switch FB1 is still in the closed state, an open command is sent to the distribution terminal corresponding to switch FB1 to trip switch FB1, thereby isolating the power supply line between the switches at both ends of the fault section and completing fault isolation. At the same time, the distribution master station determines that the switches CB1 and FB1 at both ends of the fault section are the substation outgoing line switches and the section switches on the main line respectively according to the network topology of the distribution network, that is, the switches at both ends of the fault section do not include the connecting switch. The distribution master station selects one of the connecting switches LB1 and LB2 as the connecting switch to complete the power supply recovery based on the power supply transfer strategy and the load capacity of the power supply point on the other side, and sends a closing command to the corresponding distribution terminal. After receiving the closing command, the distribution terminal executes the closing command and closes the connecting switch in combination with the state that there is pressure on one side and no pressure on the other side, thereby completing the power supply recovery of the non-fault section.

[0081] Assuming that a fault occurs at position f2, the distribution terminal protections corresponding to switches CB1 and FB1 upstream of position f2 both sense overcurrent and the protection is activated, but only the distribution terminal corresponding to switch FB1 trips switch FB1; the distribution terminal protections corresponding to switches FB11 and FB2 downstream of position f2 do not sense overcurrent and the protection is not activated. At this time, only the distribution terminal corresponding to switch FB1 sends switch position change information and protection action information to the distribution master station. After receiving the information, the distribution master station confirms that switch FB1 is the switch corresponding to the upstream distribution terminal closest to the fault position. Combined with the network topology of the distribution network, switches FB11 and FB2 located downstream of switch FB1 are determined to be the switches corresponding to the downstream distribution terminal closest to the fault position. Since switch FB1 is already in the open state, switches FB11 and FB2 are still in the closed state, so an open command is sent to the distribution terminals corresponding to switches FB11 and FB2 to trip switches FB11 and FB2, thereby isolating the power supply line between the switches at both ends of the fault section and completing fault isolation. At the same time, the distribution master station determines that the switches FB1 and switches FB11 and FB2 at both ends of the fault section are the section switches on the main line and the branch switches on the branch line, and the section switches on the main line according to the network topology of the distribution network, that is, the switches at both ends of the fault section do not include the connecting switch. The distribution master station selects one of the connecting switches LB1 and LB2 as the connecting switch to complete the power supply recovery based on the power supply transfer strategy and the load capacity of the power supply point on the other side of the connecting switches LB1 and LB2, and sends a closing command to the corresponding distribution terminal. After receiving the closing command, the distribution terminal executes the closing command and closes the connecting switch to complete the power supply recovery of the non-fault section in combination with the state that there is pressure on one side and no pressure on the other side.

[0082] Assuming that a fault occurs at position f3, the distribution terminal protections corresponding to switches CB1, FB1, FB2, and FB3 upstream of position f3 all sense overcurrent, and the protection is activated, but only the distribution terminal corresponding to switch FB3 trips switch FB3. At this time, only the distribution terminal corresponding to switch FB3 sends switch position change information and protection action information to the distribution master station. After receiving, the distribution master station confirms that switch FB3 is the switch corresponding to the upstream distribution terminal closest to the fault position. Combined with the network topology of the distribution network, it is determined that switch LB2 located downstream of switch FB3 is the switch corresponding to the downstream distribution terminal closest to the fault position. At the same time, since switch LB2 is a tie switch, that is, the switches at both ends of the fault section include the tie switch, and the tie switch LB2 itself is already in the open state, it does not need to be tripped at this time. The distribution master station does not need to send a break command to the distribution terminal corresponding to the tie switch LB2, nor does it need to restore the power supply to the non-fault section, and the fault process processing ends.

[0083] Next, we will take the longitudinal protection of the distribution terminal as an example to explain:

[0084] Assuming that a fault occurs at position f1, the distribution terminal protection corresponding to switch CB1 upstream of position f1 senses overcurrent. At the same time, since switch CB1 and switch FB1 form a protection section, the distribution terminal corresponding to switch CB1 exchanges fault information with the distribution terminal corresponding to switch FB1, and the protection is activated, and switches CB1 and FB1 are tripped. At this time, the distribution terminal corresponding to switch CB1 and the distribution terminal corresponding to switch FB1 both send switch position change information and protection action information to the distribution master station. After receiving the information, the distribution master station confirms that switch CB1 and switch FB1 are the switches corresponding to the upstream distribution terminal closest to the fault position and the switches corresponding to the downstream distribution terminal closest to the fault position, respectively. Since switch CB1 and switch FB1 are both in the open state, it can be confirmed that the switches at both ends of the fault section are open, thereby isolating the power supply line between the switches at both ends of the fault section and completing fault isolation. At the same time, the distribution master station determines that the switches CB1 and FB1 at both ends of the fault section are the substation outgoing line switches and the section switches on the main line respectively according to the network topology of the distribution network, that is, the switches at both ends of the fault section do not include the connecting switch. The distribution master station selects one of the connecting switches LB1 and LB2 as the connecting switch to complete the power supply recovery based on the power supply transfer strategy and the load capacity of the power supply point on the other side, and sends a closing command to the corresponding distribution terminal. After receiving the closing command, the distribution terminal executes the closing command and closes the connecting switch in combination with the state that there is pressure on one side and no pressure on the other side, thereby completing the power supply recovery of the non-fault section.

[0085] Assuming that a fault occurs at position f2, the distribution terminal protections corresponding to switches CB1 and FB1 upstream of position f2 both sense overcurrent. However, since switch CB1 and switch FB1 form a protection section, after the distribution terminal corresponding to switch CB1 exchanges fault information with the distribution terminal corresponding to switch FB1, the distribution terminal protection corresponding to switch CB1 does not operate. Switch FB1 forms a protection section with switches FB2 and FB11. After the distribution terminal corresponding to switch FB1 exchanges fault information with the distribution terminal corresponding to switch FB2 and the distribution terminal corresponding to switch FB11, the distribution terminal protections corresponding to switch FB1, switch FB2 and FB11 are activated, and switch FB1 and switches FB2 and FB11 are tripped. At this time, the distribution terminal corresponding to switch FB1 and the distribution terminals corresponding to switches FB2 and FB11 all send switch change information and protection action information to the distribution master station. After receiving the information, the distribution master station confirms that switch FB1 is the switch corresponding to the upstream distribution terminal closest to the fault location, and switches FB2 and FB11 are the switches corresponding to the downstream distribution terminal closest to the fault location. Since switches FB1 and switches FB2 and FB11 are all in the open state, it can be confirmed that the switches at both ends of the fault section are open, thereby isolating the power supply lines between the switches at both ends of the fault section and completing fault isolation. At the same time, the distribution master station determines that the switches FB1 and switches FB2 and FB11 at both ends of the fault section are sectional switches on the main line and sectional switches on the main line and branch switches on the branch line according to the network topology of the distribution network, that is, the switches at both ends of the fault section do not include the connecting switch. The distribution master station selects one of the connecting switches LB1 and LB2 as the connecting switch to complete the power supply recovery based on the power supply transfer strategy and the load capacity of the power supply point on the other side of the connecting switches LB1 and LB2, and sends a closing command to the corresponding distribution terminal. After receiving the closing command, the distribution terminal executes the closing command and closes the connecting switch to complete the power supply recovery of the non-fault section in combination with the state that there is pressure on one side and no pressure on the other side.

[0086] Assuming that a fault occurs at position f3, the distribution terminal protections corresponding to switches CB1, FB1, FB2, and FB3 upstream of position f3 all sense overcurrent, but only after the distribution terminal corresponding to switch FB3 exchanges fault information with the distribution terminal corresponding to the tie switch LB2, the protection of the distribution terminal corresponding to switch FB3 is activated, and switch FB3 is tripped. At this time, only the distribution terminal corresponding to switch FB3 sends switch position change information and protection action information to the distribution master station. After receiving, the distribution master station confirms that switch FB3 is the switch corresponding to the upstream distribution terminal closest to the fault position. Combined with the network topology of the distribution network, it is determined that switch LB2 located downstream of switch FB3 is the switch corresponding to the downstream distribution terminal closest to the fault position. At the same time, since switch LB2 is a tie switch, that is, the switches at both ends of the fault section include the tie switch, and the tie switch LB2 itself is already in the open state, it does not need to be tripped at this time. The distribution master station does not need to send a break command to the distribution terminal corresponding to the tie switch LB2, nor does it need to restore the power supply to the non-fault section, and the fault process processing ends.

[0087] In specific implementation, the distribution terminal on the power supply line is installed at the line switch as the detection point. The current i(t) of each detection point is collected in real time and compared with the fault detection setting threshold Iset1. When there are three consecutive current sampling values ​​i(t) greater than the fault detection setting threshold Iset1, it is determined that a fault has occurred and the distribution terminal protection is activated. Among them, when it is determined that a fault has occurred, according to different protection principles, the current of each detection point is differentiated as follows:

[0088] If the overcurrent protection principle is adopted, the current at each detection point is subjected to Fourier operation, the current amplitude I at each detection point is calculated, and compared with the overcurrent protection setting value Iset2. If the current amplitude I is greater than the overcurrent protection setting value Iset2, after a certain delay t, the protection action outlet is tripped, the distribution terminal switch is opened, and the fault is removed.

[0089] If the longitudinal directional protection principle is adopted, the current of each detection point is subjected to Fourier operation, the real part Ia1 and imaginary part Ib1 of the current of each detection point are calculated, and the data is sent to the terminal at the opposite end of the protection section, and the difference is calculated with the real part Ia2 and imaginary part Ib2 of the data transmitted by the opposite end of the protection section. The difference is compared with the set value Iset2. If ΔI is greater than Iset2, it is judged as a fault section, and the switches at both ends / three ends of the protection section are tripped to complete the fault isolation; if ΔI is less than Iset2, it is judged as a non-fault section and the protection does not operate.

[0090] See also Figure 3 On the other hand, the embodiment of the present invention further provides a distribution network fault self-healing device based on master station and terminal protection collaboration, including:

[0091] The information receiving module 110 is used to receive the switch position change information and protection action information sent by the power distribution terminal when a fault occurs;

[0092] A fault determination module 120 is used to determine switches at both ends of the fault section according to the network topology of the distribution network, switch displacement information and protection action information;

[0093] The fault isolation module 130 is used to open the switches at both ends of the fault section according to the switch displacement information, and isolate the power supply line between the switches at both ends of the fault section;

[0094] A type determination module 140 is used to determine whether the switches at both ends of the fault section include tie switches according to the topology of the distribution network;

[0095] The power supply recovery module 150 is used to control the connecting switch to close and restore the power supply to the non-fault section if the switches at both ends of the fault section do not include a connecting switch.

[0096] Optionally, in some embodiments of the present invention, the protection of the power distribution terminal adopts overcurrent protection;

[0097] The information receiving module 110 is specifically used to receive the switch position change information and protection action information sent by the first distribution terminal when a fault occurs;

[0098] The fault determination module 120 is specifically configured to determine, according to the network topology of the distribution network and the switch displacement information and protection action information sent by the first distribution terminal, that a first switch corresponding to the first distribution terminal and a second switch located downstream of the first switch are switches at both ends of the fault section;

[0099] The fault isolation module 130 is specifically used to control the second switch located downstream of the first switch to trip according to the switch displacement information sent by the first distribution terminal, so as to open the switches at both ends of the fault section and isolate the power supply line between the switches at both ends of the fault section.

[0100] Optionally, in some other embodiments of the present invention, the protection of the power distribution terminal adopts longitudinal protection;

[0101] The information receiving module 110 is specifically used to receive the switch position change information and protection action information sent by the second distribution terminal and the switch position change information and protection action information sent by the third distribution terminal when a fault occurs;

[0102] The fault determination module 120 is specifically used to determine that the third switch corresponding to the second power distribution terminal and the fourth switch corresponding to the third power distribution terminal are switches at both ends of the fault section according to the switch displacement information and protection action information sent by the second power distribution terminal and the switch displacement information and protection action information sent by the third power distribution terminal;

[0103] The fault isolation module 130 is specifically used to confirm that the third switch corresponding to the second distribution terminal and the fourth switch corresponding to the third distribution terminal are in the open state according to the switch change information sent by the second distribution terminal and the switch change information sent by the third distribution terminal, so as to open the switches at both ends of the fault section and isolate the power supply line between the switches at both ends of the fault section.

[0104] From the above, it can be seen that the embodiment of the present invention determines the switches at both ends of the fault section by receiving the switch position change information and protection action information sent by the distribution terminal when the fault occurs, combined with the network topology of the distribution network, and according to the switch position change information sent by the distribution terminal, the switches at both ends of the fault section are opened to isolate the power supply lines between the switches at both ends of the fault section, and then combined with the network topology of the distribution network, it is determined whether the switches at both ends of the fault section include a connecting switch. When it is determined that the switches at both ends of the fault section do not include a connecting switch, the connecting switch is controlled to close and the power supply to the non-fault section is restored, thereby avoiding the power loss of the non-fault section upstream of the fault point after the fault, reducing the scope of the fault power outage, and at the same time reducing the power supply recovery time downstream of the fault point, thereby improving the power supply reliability.

[0105] For the description of the relevant parts of a distribution network fault self-healing device based on coordination of master station and terminal protection provided by an embodiment of the present invention, please refer to the detailed description of the corresponding parts of a distribution network fault self-healing method based on coordination of master station and terminal protection provided by an embodiment of the present invention, and both have the corresponding effects of a distribution network fault self-healing method based on coordination of master station and terminal protection provided by an embodiment of the present invention, which will not be repeated here.

[0106] The distribution network fault self-healing device based on the collaboration of the master station and the terminal protection mentioned above is described from the perspective of the functional module. Furthermore, another aspect of the embodiment of the present invention provides a distribution network fault self-healing device based on the collaboration of the master station and the terminal protection, which is described from the perspective of hardware.

[0107] See also Figure 4 , the device comprises:

[0108] Memory 410, used for storing computer programs;

[0109] The processor 420 is used to implement the steps of the distribution network fault self-healing method based on master station and terminal protection collaboration as provided in any of the above embodiments when executing the computer program.

[0110] Among them, the processor 420 may include one or more processing cores, such as a 4-core processor, an 8-core processor, etc. The processor 420 can be implemented in at least one hardware form of DSP (Digital Signal Processing), FPGA (Field-Programmable Gate Array), and PLA (Programmable Logic Array). The processor 420 may also include a main processor and a coprocessor. The main processor is a processor for processing data in the awake state, also known as a CPU (Central Processing Unit); the coprocessor is a low-power processor for processing data in the standby state. In some embodiments, the processor 420 may be integrated with a GPU (Graphics Processing Unit), which is responsible for rendering and drawing the content to be displayed on the display screen. In some embodiments, the processor 420 may also include an AI (Artificial Intelligence) processor, which is used to process computing operations related to machine learning.

[0111] The memory 410 may include one or more computer-readable storage media, which may be non-transitory. The memory 410 may also include a high-speed random access memory, and a non-volatile memory, such as one or more disk storage devices, flash memory storage devices. In this embodiment, the memory 410 is at least used to store the following computer program, wherein, after the computer program is loaded and executed by the processor, the relevant steps of the distribution network fault self-healing method based on the coordination of the master station and the terminal protection disclosed in any of the aforementioned embodiments can be implemented. In addition, the resources stored in the memory 410 may also include an operating system and data, etc., and the storage method may be temporary storage or permanent storage. Among them, the operating system may include Windows, Unix, Linux, etc., and the data may include but is not limited to data corresponding to the test results, etc.

[0112] It is understandable that if the distribution network fault self-healing method based on the coordination of master station and terminal protection provided in any of the above embodiments is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or part of the contribution to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium to execute all or part of the steps of each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), electrically erasable programmable ROM, register, hard disk, removable disk, CD-ROM, disk or optical disk and other media that can store program code.

[0113] In view of this, another aspect of an embodiment of the present invention provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the distribution network fault self-healing method based on the collaboration of master station and terminal protection as provided in any of the above embodiments are implemented.

[0114] The functions of each functional module of the computer-readable storage medium provided in the embodiment of the present invention can be specifically implemented according to the method in any of the above method embodiments. The specific implementation process can refer to the relevant description of any of the above method embodiments, which will not be repeated here.

[0115] Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A distribution network fault self-healing method based on master station and terminal protection collaboration, characterized in that: include: Receive switch position change information and protection action information sent by the distribution terminal when a fault occurs; When a fault occurs, the protection of the distribution terminal that detects the fault is activated, and the distribution terminal in the fault section selectively trips the upstream switch of the fault location or the upstream / downstream switch of the fault location to cut off the fault, and sends the switch position change information and protection action information at the same time; Determine switches at both ends of the fault section according to the topological structure of the distribution network and the switch displacement information and protection action information; By inspecting the distribution network power supply lines by judging the switch position change information and protection action information sent by the distribution terminals in the fault section, it can be determined that the switches corresponding to the distribution terminals at both ends of the fault section are the switches corresponding to the upstream distribution terminals closest to the fault location or the switches corresponding to the downstream distribution terminals closest to the fault location; According to the switch displacement information, the switches at both ends of the fault section are opened to isolate the power supply lines between the switches at both ends of the fault section; According to the network topology of the distribution network, determining whether the switches at both ends of the fault section include tie switches; If the switches at both ends of the fault section do not include a tie switch, the tie switch is controlled to close to restore power supply to the non-fault section; The protection of the power distribution terminal adopts overcurrent protection; the switch position change information and protection action information include the switch position change information and protection action information sent by the first power distribution terminal; The method of determining switches at both ends of the fault section according to the topological structure of the distribution network and the switch displacement information and protection action information includes: According to the network topology of the distribution network and the switch position change information and protection action information sent by the first distribution terminal, it is determined that the first switch corresponding to the first distribution terminal and the second switch located downstream of the first switch are the switches at both ends of the fault section.

2. A distribution network fault self-healing method based on master station and terminal protection collaboration, characterized in that: include: Receive switch position change information and protection action information sent by the distribution terminal when a fault occurs; When a fault occurs, the protection of the distribution terminal that detects the fault is activated, and the distribution terminal in the fault section selectively trips the upstream switch of the fault location or the upstream / downstream switch of the fault location to cut off the fault, and sends the switch position change information and protection action information at the same time; Determine switches at both ends of the fault section according to the network topology of the distribution network and the switch displacement information and protection action information; By inspecting the distribution network power supply lines by judging the switch position change information and protection action information sent by the distribution terminals in the fault section, it can be determined that the switches corresponding to the distribution terminals at both ends of the fault section are the switches corresponding to the upstream distribution terminals closest to the fault location or the switches corresponding to the downstream distribution terminals closest to the fault location; According to the switch displacement information, the switches at both ends of the fault section are opened to isolate the power supply lines between the switches at both ends of the fault section; According to the network topology of the distribution network, determining whether the switches at both ends of the fault section include tie switches; If the switches at both ends of the fault section do not include a tie switch, the tie switch is controlled to close to restore power supply to the non-fault section; The protection of the distribution terminal adopts longitudinal protection; the switch position change information and protection action information include the switch position change information and protection action information sent by the second distribution terminal and the switch position change information and protection action information sent by the third distribution terminal; The method of determining switches at both ends of the fault section according to the topological structure of the distribution network and the switch displacement information and protection action information includes: According to the switch change information and protection action information sent by the second distribution terminal and the switch change information and protection action information sent by the third distribution terminal, it is determined that the third switch corresponding to the second distribution terminal and the fourth switch corresponding to the third distribution terminal are the switches at both ends of the fault section.

3. The distribution network fault self-healing method based on master station and terminal protection collaboration according to claim 1 is characterized in that: The method of opening the switches at both ends of the fault section according to the switch displacement information and isolating the power supply lines between the switches at both ends of the fault section includes: According to the switch position change information sent by the first power distribution terminal, the second switch located downstream of the first switch is controlled to trip, so that the switches at both ends of the fault section are opened, and the power supply line between the switches at both ends of the fault section is isolated.

4. The distribution network fault self-healing method based on master station and terminal protection collaboration according to claim 2 is characterized in that: The method of opening the switches at both ends of the fault section according to the switch displacement information and isolating the power supply lines between the switches at both ends of the fault section includes: According to the switch position change information sent by the second distribution terminal and the switch position change information sent by the third distribution terminal, confirm that the third switch corresponding to the second distribution terminal and the fourth switch corresponding to the third distribution terminal are in the open state, so that the switches at both ends of the fault section are opened, and the power supply lines between the switches at both ends of the fault section are isolated.

5. A distribution network fault self-healing device based on master station and terminal protection collaboration, characterized in that: include: An information receiving module, used to receive switch position change information and protection action information sent by the power distribution terminal when a fault occurs; When a fault occurs, the protection of the distribution terminal that detects the fault is activated, and the distribution terminal in the fault section selectively trips the upstream switch of the fault location or the upstream / downstream switch of the fault location to cut off the fault, and sends the switch position change information and protection action information at the same time; A fault determination module is used to determine the switches at both ends of the fault section according to the network topology of the distribution network and the switch displacement information and protection action information; By inspecting the distribution network power supply lines by judging the switch position change information and protection action information sent by the distribution terminals in the fault section, it can be determined that the switches corresponding to the distribution terminals at both ends of the fault section are the switches corresponding to the upstream distribution terminals closest to the fault location or the switches corresponding to the downstream distribution terminals closest to the fault location; A fault isolation module, used to open the switches at both ends of the fault section according to the switch displacement information, and isolate the power supply line between the switches at both ends of the fault section; A type determination module, used to determine whether the switches at both ends of the fault section include tie switches according to the network topology of the distribution network; A power supply recovery module, used for controlling the connecting switch to close and recovering the power supply to the non-fault section if the switches at both ends of the fault section do not include a connecting switch; The protection of the power distribution terminal adopts overcurrent protection; The information receiving module is specifically used to receive the switch position change information and protection action information sent by the first distribution terminal when a fault occurs; The fault determination module is specifically used to determine that a first switch corresponding to the first distribution terminal and a second switch located downstream of the first switch are switches at both ends of the fault section according to the network topology of the distribution network and the switch displacement information and protection action information sent by the first distribution terminal; The fault isolation module is specifically used to control the second switch located downstream of the first switch to trip according to the switch change information sent by the first distribution terminal, so as to open the switches at both ends of the fault section and isolate the power supply line between the switches at both ends of the fault section.

6. A distribution network fault self-healing device based on master station and terminal protection collaboration, characterized in that: include: An information receiving module, used to receive switch position change information and protection action information sent by the power distribution terminal when a fault occurs; When a fault occurs, the protection of the distribution terminal that detects the fault is activated, and the distribution terminal in the fault section selectively trips the upstream switch of the fault location or the upstream / downstream switch of the fault location to cut off the fault, and sends the switch position change information and protection action information at the same time; A fault determination module is used to determine the switches at both ends of the fault section according to the network topology of the distribution network and the switch displacement information and protection action information; By inspecting the distribution network power supply lines by judging the switch position change information and protection action information sent by the distribution terminals in the fault section, it can be determined that the switches corresponding to the distribution terminals at both ends of the fault section are the switches corresponding to the upstream distribution terminals closest to the fault location or the switches corresponding to the downstream distribution terminals closest to the fault location; A fault isolation module, used to open the switches at both ends of the fault section according to the switch displacement information, and isolate the power supply line between the switches at both ends of the fault section; A type determination module, used to determine whether the switches at both ends of the fault section include tie switches according to the network topology of the distribution network; A power supply recovery module, used for controlling the connecting switch to close and recovering the power supply to the non-fault section if the switches at both ends of the fault section do not include a connecting switch; The protection of the distribution terminal adopts longitudinal protection; The information receiving module is specifically used to receive the switch position change information and protection action information sent by the second distribution terminal and the switch position change information and protection action information sent by the third distribution terminal when a fault occurs; The fault determination module is specifically used to determine that the third switch corresponding to the second power distribution terminal and the fourth switch corresponding to the third power distribution terminal are switches at both ends of the fault section according to the switch displacement information and protection action information sent by the second power distribution terminal and the switch displacement information and protection action information sent by the third power distribution terminal; The fault isolation module is specifically used to confirm that the third switch corresponding to the second distribution terminal and the fourth switch corresponding to the third distribution terminal are in the open state based on the switch change information sent by the second distribution terminal and the switch change information sent by the third distribution terminal, so as to open the switches at both ends of the fault section and isolate the power supply line between the switches at both ends of the fault section.

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