Power grid situation assessment method based on topology linkage and power flow calculation

Abstract

The present invention discloses a power grid situation assessment method based on topology linkage and power flow calculation. The method includes obtaining power grid topology and operation information, reconstructing a power grid topology calculation model, topology linkage modeling of backup and automatic switching strategies, real-time analysis of power grid equipment failures, power grid topology calculation analysis, and situation assessment results. Compared with existing technologies, this method achieves quasi-real-time assessment of power grid operation status under fault conditions, providing a solution for power grid dispatching and operation to quickly grasp the power grid operation status and assist in decision-making. Through topology linkage analysis and power flow calculation analysis, the power grid operation status is assessed from two levels: the scope of the power grid's impact and the degree of safety and stability. A quasi-real-time auxiliary decision-making solution can be provided, improving the level of intelligent deduction of power grid operation status under power grid equipment failure conditions.

Description

Technical Field

[0001] The present invention relates to the technical field of power grid operation safety analysis, and in particular to a power grid situation assessment method based on topology linkage and power flow calculation. Background Art

[0002] With the continuous development of new energy, the grid load is obviously transferred back to high voltage levels. The safe and stable operation level of the grid needs to be improved under the new power system. At the same time, severe weather occurs frequently, and the grid dispatching and operation personnel are under great pressure. It is particularly important to be able to actively and accurately deduce the grid operation status and assist the dispatching and operation personnel in the first time.

[0003] Power grid simulation analysis requires highly accurate digital power grid simulation modeling. Especially when a power outage occurs, the power grid topology will develop and change. Being able to know the changes in the first place, analyze the power grid operation status and risks, and quickly draw simulation conclusions has great practical significance. Summary of the Invention

[0004] The present invention provides a power grid situation assessment method based on topology linkage and power flow calculation.

[0005] The present invention is achieved through the following technical solutions:

[0006] The power grid situation assessment method based on topology linkage and power flow calculation includes the following steps:

[0007] Step 1: Obtain grid topology and operation information.

[0008] Obtain the primary equipment ledger, topological relationship and quasi-real-time primary equipment operation information of the power grid from the smart grid dispatching technology support platform. The primary equipment ledger of the power grid includes switches, circuit breakers, lines, transformers, busbars and stations. The quasi-real-time primary equipment operation information acquisition cycle is 5 minutes or 1 minute.

[0009] Step 2: Reconstruct the grid topology calculation model.

[0010] Using the power system analysis program PSD-BPA flow calculation file as the carrier, the data of the power grid primary equipment ledger, topological relationship and quasi-real-time primary equipment operation information in step one are directly reconstructed into a PSD-BPA flow data file through computer graph theory algorithm. The PSD-BPA flow data file is a power grid topology calculation model, which has both topology analysis basis and flow calculation function.

[0011] Step 3: Modeling the topological linkage of the backup and self-investment strategies.

[0012] Extract the automatic backup action strategy from the automatic backup ledger, map the action devices and linkage devices in the strategy with the power grid topology calculation model in step 2, and construct a topology linkage model.

[0013] Step 4: Real-time analysis of power grid equipment failures.

[0014] The remote signaling alarm information and switch position change information of the grid secondary equipment are obtained in real time from the smart grid dispatching technology support platform. The device with the grid status change is determined by the switch position change information. The remote signaling alarm information of the grid secondary equipment is further determined to be the device whose grid status change is caused by a fault, and the grid fault device information is then obtained.

[0015] Step 5: Grid topology calculation analysis and situation assessment results.

[0016] Based on steps 2 and 3, the grid fault device in step 4 is placed in the grid topology model at the moment before the equipment failure. By simulating the equipment failure and outage, the backup and automatic switching strategy linkage simulation is realized, and the impact range of the grid outage after the equipment outage is given.

[0017] The power grid topology calculation model after fault simulation is analyzed through power flow calculation to give the thermal stability of the power grid and form the ultra-short-term operation status results of the power grid.

[0018] Furthermore, in the step 2, the PSD-BPA tidal current data file is reconstructed by:

[0019] Automatically convert busbars and unit equipment into B cards in the BPA node model;

[0020] Line equipment automatically converts to BPA branch model L card;

[0021] Automatically convert two-winding transformers into BPA branch model T-cards;

[0022] The three-winding transformer is automatically converted into three BPA branch model T cards and one virtual node model B card;

[0023] The T-connection point in the power grid T-connection structure is converted into a virtual node B card, the circuit breaker in the power grid 3 / 2 connection is converted into a virtual branch L card, and a virtual node B card is generated between the two circuit breakers;

[0024] The busbar circuit breaker is converted into a virtual branch L card;

[0025] The circuit breaker / knife switch disconnect device status is converted to branch card status;

[0026] Convert real-time measurement data into calculation model operation status and load data;

[0027] Based on the graph theory layer-order traversal algorithm, the data of the largest connected subgraph of the power grid is retained, the isolated island data is discarded, the data card status is modified, and the power flow data file is assembled according to the PSD-BPA program rules.

[0028] The beneficial effects of the present invention are:

[0029] The proposed grid situation assessment method, based on topology linkage and power flow calculation, achieves near-real-time assessment of grid operating status in the event of a fault, compared to existing technologies. This provides a solution for grid dispatchers to quickly understand grid operating status and assist in decision-making. Through topology linkage analysis and power flow calculation, the grid operating status is assessed from two perspectives: the scope of impact and the degree of safety and stability. Assisted decision-making solutions can be provided in near-real time, improving the level of intelligent deduction of grid operating status in the event of a grid equipment fault. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a flow chart of the power grid situation assessment method based on topology linkage and power flow calculation provided by the present invention. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be described in further detail. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0032] The present invention is achieved through the following technical solutions:

[0033] See also Figure 1 , Figure 1 This is a flow chart of the power grid situation assessment method based on topology linkage and power flow calculation provided by the present invention.

[0034] The power grid situation assessment method based on topology linkage and power flow calculation includes the following steps:

[0035] Step 1: Obtain grid topology and operation information.

[0036] Obtain the primary equipment ledger, topological relationship and quasi-real-time primary equipment operation information of the power grid from the smart grid dispatching technology support platform. The primary equipment ledger of the power grid includes switches, circuit breakers, lines, transformers, busbars and stations. The quasi-real-time primary equipment operation information acquisition cycle is 5 minutes or 1 minute.

[0037] Step 2: Reconstruct the grid topology calculation model.

[0038] Using the power system analysis program PSD-BPA flow calculation file as the carrier, the data of the power grid primary equipment ledger, topological relationship and quasi-real-time primary equipment operation information in step one are directly reconstructed into a PSD-BPA flow data file through computer graph theory algorithm. The PSD-BPA flow data file is a power grid topology calculation model, which has both topology analysis basis and flow calculation function.

[0039] The specific reconstruction method of the PSD-BPA tidal current data file is as follows:

[0040] Automatically convert busbars, units and other equipment into B cards in the BPA node model;

[0041] Line equipment automatically converts to BPA branch model L card;

[0042] Automatically convert two-winding transformers into BPA branch model T-cards;

[0043] The three-winding transformer is automatically converted into three BPA branch model T cards and one virtual node model B card;

[0044] The T-connection point in the power grid T-connection structure is converted into a virtual node B card, the circuit breaker in the power grid 3 / 2 connection is converted into a virtual branch L card, and a virtual node B card is generated between the two circuit breakers;

[0045] The busbar circuit breaker is converted into a virtual branch L card;

[0046] The state of the circuit breaker / knife switch and other disconnecting devices is converted to the branch card state;

[0047] Convert real-time measurement data into calculation model operation status and load data;

[0048] Based on the graph theory layer-order traversal algorithm, the data of the largest connected subgraph of the power grid is retained, the isolated island data is discarded, the data card status is modified, and the power flow data file is assembled according to the PSD-BPA program rules.

[0049] Step 3: Modeling the topological linkage of the backup and self-investment strategies.

[0050] Extract the automatic backup action strategy from the automatic backup ledger, map the action devices and linkage devices in the strategy with the power grid topology calculation model in step 2, and construct a topology linkage model.

[0051] Step 4: Real-time analysis of power grid equipment failures.

[0052] The remote signaling alarm information and switch position change information of the grid secondary equipment are obtained in real time from the smart grid dispatching technology support platform. The device with the grid status change is determined by the switch position change information. The remote signaling alarm information of the grid secondary equipment is further determined to be the device whose grid status change is caused by a fault, and the grid fault device information is then obtained.

[0053] Step 5: Grid topology calculation analysis and situation assessment results.

[0054] Based on steps 2 and 3, the grid fault device in step 4 is placed in the grid topology model at the moment before the equipment failure. By simulating the equipment failure and outage, the backup and automatic switching strategy linkage simulation is realized, and the impact range of the grid outage after the equipment outage is given.

[0055] The power grid topology calculation model after fault simulation is analyzed through power flow calculation to give the thermal stability of the power grid and form the ultra-short-term operation status results of the power grid.

[0056] The beneficial effects of the present invention are:

[0057] The proposed grid situation assessment method, based on topology linkage and power flow calculation, achieves near-real-time assessment of grid operating status in the event of a fault, compared to existing technologies. This provides a solution for grid dispatchers to quickly understand grid operating status and assist in decision-making. Through topology linkage analysis and power flow calculation, the grid operating status is assessed from two perspectives: the scope of impact and the degree of safety and stability. Assisted decision-making solutions can be provided in near-real time, improving the level of intelligent deduction of grid operating status in the event of a grid equipment fault.

[0058] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely preferred examples of the present invention and are not intended to limit the present invention. Various changes and improvements may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and improvements fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. A power grid situation assessment method based on topology linkage and power flow calculation, characterized in that: The following steps are involved: Step 1: Obtain grid topology and operation information; Obtaining the primary equipment ledger, topological relationships, and quasi-real-time primary equipment operating information from the smart grid dispatching technology support platform. The primary equipment ledger includes switches, circuit breakers, lines, transformers, busbars, and stations. The quasi-real-time primary equipment operating information acquisition cycle is 5 minutes or 1 minute. Step 2: Reconstruct the grid topology calculation model; Using the power system analysis program PSD-BPA power flow calculation file as the carrier, the data of the power grid primary equipment ledger, topological relationship and quasi-real-time primary equipment operation information in step 1 are directly reconstructed into a PSD-BPA power flow data file through computer graph theory algorithms. The PSD-BPA power flow data file is a power grid topology calculation model that has both a topology analysis foundation and a power flow calculation function. Reconstruct the PSD-BPA tidal current data file. The specific reconstruction method is: Automatically convert busbars and unit equipment into B cards in the BPA node model; Line equipment automatically converts to BPA branch model L card; Automatically convert two-winding transformers into BPA branch model T-cards; The three-winding transformer is automatically converted into three BPA branch model T cards and one virtual node model B card; The T-connection point in the power grid T-connection structure is converted into a virtual node B card, the circuit breaker in the power grid 3 / 2 connection is converted into a virtual branch L card, and a virtual node B card is generated between the two circuit breakers; The busbar circuit breaker is converted into a virtual branch L card; The circuit breaker / knife switch disconnect device status is converted to branch card status; Convert real-time measurement data into calculation model operation status and load data; Based on the graph theory layer-order traversal algorithm, the largest connected subgraph data of the power grid is retained, isolated island data is discarded, the data card status is modified, and the power flow data file is assembled according to the PSD-BPA program rules; Step 3: Modeling the topology linkage of the backup and self-investment strategies; Extract the automatic backup operation strategy from the automatic backup operation ledger, map the action devices and linkage devices in the strategy to the power grid topology calculation model in step 2, and thus construct a topology linkage model; Step 4: Real-time analysis and judgment of power grid equipment failures; Real-time remote signaling alarm information and switch position information of grid secondary equipment are obtained from the smart grid dispatching technology support platform. The switch position information is used to determine the device with the grid status change. The remote signaling alarm information of the grid secondary equipment is used to further determine whether the device is causing the grid status change due to a fault, thereby obtaining the grid fault device information. Step 5: Grid topology calculation analysis and situation assessment results; Based on steps 2 and 3, the grid topology model immediately before the device failure is populated with the faulty device from step 4. By simulating the device failure and outage, a coordinated simulation of the backup and automatic switching strategies is implemented to determine the impact of the grid outage after the device outage. The power grid topology calculation model after fault simulation is analyzed through power flow calculation to give the thermal stability of the power grid and form the ultra-short-term operation status results of the power grid.

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