A method and device for measuring phase quantities with load during the power transmission of the startup and standby transformer

Abstract

The present application provides a method and device for measuring phase quantities with load during the power transmission of the startup and standby transformer, relating to the technical field of power equipment operation and maintenance, including: controlling the startup and standby transformer system to perform voltage transformer phase checking and capacitor bank charging; after the voltage transformer phase checking is correct and the capacitor charging is completed, controlling the closing of the side switch of the startup and standby transformer, and performing the test of the secondary current and phase of the differential protection under the closing of the side switch of the startup and standby transformer to obtain the first test result; wherein, the first test result includes the phasor of the startup and standby transformer; determining whether the startup and standby transformer can be safely put into operation according to the pre-calculated current, voltage, phase of the current transformer and the first test result. The present application can achieve the purpose of measuring phase quantities with load during the power transmission of the startup and standby transformer by replacing the plant load.

Description

Technical Field

[0001] The present application relates to the field of operation and maintenance of power equipment, and specifically to a method and device for measuring phasors with load during the power transmission of the startup and standby transformer. Background Art

[0002] During the live phase of the step-up substation system in a newly built power plant, phasor tests can usually be carried out by using the line no-load charging current and switching reactors. Specifically, the phasors of the voltage and current secondary circuits of various protection devices, measuring devices, and automation devices are tested, and then combined with the operating conditions of the primary equipment to judge the correctness of the secondary circuits of these devices.

[0003] In the step-up substation system, the power reception of the startup and standby transformer generally occurs in the initial stage of the power plant construction. Various auxiliary machines are in the installation and commissioning stage. After the commissioning conditions of specialties such as thermal engineering, steam turbine, and boiler are met, equipment such as the mill, auxiliary circulating water pump, motor-driven feed pump, induced draft fan, primary air fan, and forced draft fan in the 10 kV section of the plant service can be started. Therefore, the plant service auxiliary machines are usually in an unloaded state, with a very small actual load, and there are situations such as three-phase asymmetry or large fluctuations in the load, which easily cause the problem that the load is large when measuring the amplitude of one-phase current, while the load is small when measuring the amplitude of another-phase current, making it difficult to meet the phasor test requirements. In order to correctly put into operation the differential protection of the startup and standby transformer as soon as possible, the dispatcher generally requires the power plant to quickly start the load for the protection phasor test so that the relevant protection devices can be put into operation. However, during the load organization stage of the phasor test, it is usually the first time that a large number of auxiliary machines in the power plant are energized, which poses a safety risk. It requires close cooperation among multiple professionals, and the time from load organization to the end of the test is relatively long, and load organization is difficult. Therefore, it is necessary to find a device to replace the plant service load to achieve the purpose of measuring phasors with load. Summary of the Invention

[0004] Aiming at the problems in the prior art, the present application provides a method and device for measuring phasors with load during the power transmission of the startup and standby transformer, which can replace the plant service load to achieve the purpose of measuring phasors with load during the power transmission of the startup and standby transformer.

[0005] To solve the above technical problems, the present application provides the following technical solutions:

[0006] In a first aspect, the present application provides a method for measuring phasors with load during the power transmission of the startup and standby transformer, including:

[0007] Controlling the startup and standby transformer system to perform voltage transformer phase checking and capacitor bank charging;

[0008] After the voltage transformer phase checking is correct and the capacitor charging is completed, controlling the closing of the side switch of the startup and standby transformer, and performing the test of the differential protection secondary current and phase under the closing of the side switch of the startup and standby transformer to obtain a first test result; wherein, the first test result includes the phasor of the startup and standby transformer;

[0009] Determine whether the start-up and standby transformer can be safely put into operation based on the pre-calculated current, voltage, phase of the current transformer and the first test result.

[0010] Further, controlling the start-up and standby transformer system to perform voltage transformer phase checking and capacitor bank charging includes:

[0011] After determining that the insulation state of the primary equipment is normal, control the closing of the standby incoming line switches of each section;

[0012] Perform voltage transformer phase checking on the high-voltage side voltage of the start-up and standby transformer and the incoming line voltages of each section;

[0013] Control the closing of the capacitor bank switch to charge the capacitor bank.

[0014] Further, the first test result further includes the transformation ratio of the current transformer, the current direction, the load-side measured current phasor and phase, and the current phase of the corresponding phase on the power supply side; performing the test on the secondary current and phase of the differential protection under the closing of the start-up and standby transformer side switch to obtain the first test result includes:

[0015] Measure the current value of the equipment related to the secondary current and the phase angle of the reference phasor to obtain the phasor of the start-up and standby transformer;

[0016] Calculate the differential current according to the current value and the phase angle of the reference phasor;

[0017] When the differential current meets the threshold, check the transformation ratio of each current transformer, the current direction, the load-side measured current phasor and phase, and the current phase of the corresponding phase on the power supply side.

[0018] Further, determining whether the start-up and standby transformer can be safely put into operation according to the pre-calculated current, voltage, phase of the current transformer and the first test result includes:

[0019] Calculate the required current, required voltage and required phase of the current transformer according to the current loop structure of the start-up and standby transformer system and the capacity of the capacitor bank;

[0020] Judge whether the secondary polarity of the current transformer is correct according to the required current, required voltage and required phase, the power flow direction of the start-up and standby transformer system and the first test result, so as to determine whether the start-up and standby transformer can be safely put into operation.

[0021] Further, the method for measuring the phasor of the start-up and standby transformer when it is energized with load further includes:

[0022] Control the closing of the switch in the start-up and standby transformer, and perform the test on the secondary current and phase of the differential protection under the closing of the switch in the start-up and standby transformer to obtain the second test result;

[0023] Based on the second test result, determine whether the secondary polarity of the current transformer of the switch in the start-up and standby transformer is correct. If it is, put the start-up and standby transformer into operation.

[0024] In a second aspect, the present application provides a device for measuring phase vectors during the power transmission of a start-up and standby transformer, including:

[0025] A phase verification and charging unit for controlling the start-up and standby transformer system to perform voltage transformer phase verification and capacitor bank charging;

[0026] A first phase vector test unit for controlling the closing of the start-up and standby transformer side switch and testing the secondary current and phase of the differential protection under the closing of the start-up and standby transformer side switch to obtain a first test result after the voltage transformer phase verification is correct and the capacitor charging is completed; wherein, the first test result includes the phase vectors of the start-up and standby transformer.

[0027] A first operation safety detection unit for determining whether the start-up and standby transformer can be safely put into operation according to the pre-calculated current, voltage, phase of the current transformer and the first test result.

[0028] Further, the phase verification and charging unit includes:

[0029] An incoming line closing control module for controlling the closing of each section of standby incoming line switch after determining that the insulation state of the primary equipment is normal;

[0030] A voltage phase verification module for performing voltage transformer phase verification on the high-voltage side voltage of the start-up and standby transformer and the voltage of each section of incoming line;

[0031] A capacitor charging module for controlling the closing of the capacitor bank switch to charge the capacitor bank.

[0032] Further, the first test result further includes the transformation ratio of the current transformer, the current direction, the load measurement current phase vector and phase, and the current phase of the corresponding phase on the power supply side; the first phase vector test unit includes:

[0033] A phase vector measurement module for measuring the current value of the secondary current-related equipment and the phase angle of the reference phase vector to obtain the phase vectors of the start-up and standby transformer;

[0034] A differential current calculation module for calculating the differential current from the current value and the phase angle of the reference phase vector;

[0035] A current measurement module for checking the transformation ratio of each current transformer, the current direction, the load measurement current phase vector and phase, and the current phase of the corresponding phase on the power supply side when the differential current meets the threshold.

[0036] Further, the operation safety detection unit includes:

[0037] A demand calculation module, used to calculate the demand current, demand voltage and demand phase of the current transformer according to the current loop structure of the start-up and standby transformer system and the capacity of the capacitor bank;

[0038] The commissioning safety detection module is used to judge whether the secondary polarity of the current transformer is correct according to the required current, required voltage and required phase, the flow direction of the starting and standby transformer system and the first test result, so as to determine whether the starting and standby transformer can be safely commissioned.

[0039] Furthermore, the device for measuring phase quantities of power transmission with load also includes:

[0040] A second phasor test unit is used to control the closing of the switch in the standby transformer and to test the secondary current and phase of the differential protection when the switch in the standby transformer is closed to obtain a second test result;

[0041] The second operation safety detection unit is used to determine whether the secondary polarity of the current transformer of the switch in the standby transformer is correct according to the second test result, and if so, put the standby transformer into operation.

[0042] In a third aspect, the present application provides an electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the method for measuring phase quantities of a standby transformer with load when executing the program.

[0043] In a fourth aspect, the present application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method for measuring phase quantities of a standby transformer with load.

[0044] In a fifth aspect, the present application provides a computer program product, including a computer program / instruction, which, when executed by a processor, implements the steps of the method for measuring phase quantities of a standby transformer with load.

[0045] In response to the problems in the prior art, the method and device for measuring the phase quantity of the starting and standby transformer with load provided in the present application can complete the phase quantity test of each unit of the starting and standby transformer at one time, greatly shortening the test time. After the polarity of the current transformers and the related protection differential current of the booster station and the starting and standby transformer are correctly re-measured, the starting and standby transformer protection can be put into operation as soon as possible, that is, the booster station and the starting and standby transformer can be started and put into production, ensuring the efficiency of the test and providing safety guarantee for the system trial operation of the units. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0047] Figure 1 It is a flowchart of the method for measuring phase vectors with load when the startup and standby transformer is energized in the embodiment of the present application;

[0048] Figure 2 It is a flowchart of voltage transformer phase checking and capacitor bank charging in the embodiment of the present application;

[0049] Figure 3 It is a flowchart of the test of the secondary current and phase of the differential protection when the side switch of the startup and standby transformer is closed in the embodiment of the present application;

[0050] Figure 4 It is one of the flowcharts for detecting whether the startup and standby transformer can be safely put into operation in the embodiment of the present application;

[0051] Figure 5 It is another flowchart for detecting whether the startup and standby transformer can be safely put into operation in the embodiment of the present application;

[0052] Figure 6 It is one of the structural diagrams of the device for measuring phase vectors with load when the startup and standby transformer is energized in the embodiment of the present application;

[0053] Figure 7 It is the structural diagram of the phase checking and charging unit in the embodiment of the present application;

[0054] Figure 8 It is the structural diagram of the first phase vector test unit in the embodiment of the present application;

[0055] Figure 9 It is the structural diagram of the safe operation detection unit in the embodiment of the present application;

[0056] Figure 10 It is another structural diagram of the device for measuring phase vectors with load when the startup and standby transformer is energized in the embodiment of the present application;

[0057] Figure 11 It is the structural schematic diagram of the electronic device in the embodiment of the present application;

[0058] Figure 12 It is the structural schematic diagram of the startup and standby transformer and the main wiring of the plant in the embodiment of the present application;

[0059] Figure 13 It is the schematic diagram of the operating modes of each switch when measuring the phase vectors of the startup and standby transformer in the embodiment of the present application;

[0060] Figure 14 Schematic diagram of load change in the embodiment of the present application. Detailed implementation manners

[0061] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0062] In the technical solutions of the present application, the acquisition, storage, use, and processing of data all comply with the relevant regulations of laws and regulations.

[0063] In one embodiment, referring to Figure 1 , in order to be able to replace the auxiliary load to achieve the purpose of measuring the phase vector when the start-up and standby transformer supplies power and is loaded, the present application provides a method for measuring the phase vector when the start-up and standby transformer supplies power and is loaded, including:

[0064] S101: Control the start-up and standby transformer system to perform voltage transformer phase checking and capacitor bank charging;

[0065] S102: After the voltage transformer phase checking is correct and the capacitor charging is completed, control the closing of the start-up and standby transformer side switch, and perform the test of the secondary current and phase of the differential protection under the closing of the start-up and standby transformer side switch to obtain a first test result; wherein, the first test result includes the phase vector of the start-up and standby transformer;

[0066] S103: Determine whether the start-up and standby transformer can be safely put into operation according to the pre-calculated current, voltage, phase of the current transformer and the first test result.

[0067] It can be understood that Figure 12 Schematic diagram of the structure of the start-up and standby transformer and the auxiliary main wiring in the embodiment of the present application. Among them, it includes: start-up and standby transformer side switch 1 of the step-up substation; middle switch of the start-up and standby transformer of the step-up substation; 2 high-voltage side disconnectors 3 of the start-up and standby transformer; standby incoming line switch 4 of 10kV 1A section of Unit 1; standby incoming line switch 5 of 10kV 1B section of Unit 1; standby incoming line switch 6 of 10kV 2A section of Unit 2; standby incoming line switch 7 of 10kV 2B section of Unit 2; capacitor bank switch 8 of 10kV 1A section of Unit 1; capacitor bank switch 9 of 10kV 1B section of Unit 1; capacitor bank switch 10 of 10kV 2A section of Unit 2; capacitor bank switch 11 of 10kV 2B section of Unit 2. Among them, PT refers to the voltage transformer; CT refers to the current transformer.

[0068] The primary wiring mode of the booster station is "one and a half circuit breaker wiring". The power supply of the starter transformer is connected by stepping down the 500kV busbar. Two units share one starter transformer, of which the 10kV 1A and 1B sections supply the plant load of unit 1, and the 10kV 2A and 2B sections supply the plant load of unit 2. The 10kV side of the starter transformer is connected to the 10kV working busbar of each unit through the common box busbar as the starting / standby power supply; the control, monitoring and signal circuits of the switch and auxiliary knife switch of the booster station are realized through the network control NCS system; all the switch control circuits and signals of the 10kV starter transformer are controlled by the thermal DCS distributed control system. The operator operates the electrical switch through the NCS / DCS control system. The NCS / DCS screen button is connected to the NCS / DCS logic drive level. When the controller receives the NCS / DCS command, it drives the relay to close and connects to the switch's closing and opening circuit through the secondary cable to realize remote control of the switch. Therefore, the execution subject of the embodiment of the present application may be an NCS / DCS control system, the core of which is a controller.

[0069] The embodiment of the present application installs capacitors in the 10kV standby load switch cabinet, and after the standby transformer is powered on, the capacitor bank is used as the load detection phasor. The entire debugging method has a simple operation process, and the phasor tests of the standby transformer plant unit 1 and unit 2 can be completed at one time, which greatly shortens the debugging time, enables the standby transformer protection to be put into operation as soon as possible, ensures the high efficiency of the test, and provides safety guarantee for the unit system test operation.

[0070] The following points need to be explained:

[0071] First, the test of the phase and size of each CT winding using the working voltage and load current is the last test to verify the correctness of the CT polarity and ratio, to ensure the safe and reliable operation of the equipment after commissioning, and to prevent malfunctions such as differential protection. Therefore, during the start-up and standby power transmission process, the phasor test of all CT circuits can be completed and protection can be put into use as soon as possible to meet the requirements of the "Inspection Regulations for Relay Protection and Grid Safety Automatic Devices".

[0072] Second, unlike conventional operations before load testing, the capacitor current load testing method adopted in the embodiment of the present application can save a large number of operating steps for primary equipment, reduce the risk of the first trial operation of auxiliary equipment, and also help to improve the efficiency of plant power-on, making a significant contribution to the system trial operation of the unit.

[0073] Third, when using the capacitor current load method for testing, based on the capacitor capacity and current loop information, on the one hand, the secondary amplitude (current) of the CT used for the corresponding protection and the phase relationship between current and voltage can be calculated; on the other hand, combined with the flow direction, the quadrant of the vector diagram in which the current of each phase measured by the phase meter is located can be predicted; a vector diagram is made based on the test data for verification, and then it is determined whether the secondary polarity of the current transformer is correct.

[0074] Fourth, the capacitor current load method is adopted. If a secondary wiring error occurs during the test, the corresponding capacitor can be withdrawn without affecting the test work of other CT circuits. On the other hand, the capacitor 10kV switch comprehensive protection device is in protection-in state. If there is a fault protection, the switch of the corresponding capacitor can be tripped to ensure the safety of personnel and equipment.

[0075] Fifth, the conventional load method requires a long operation and load time, and the current amplitude and phase are greatly affected by the load changes, which can easily affect the first test result. The capacitor current load method has simple operation steps and short test time. The capacitor load test can ensure the continuous, stable and safe operation of the system, with significant economic benefits.

[0076] Sixth, since the capacitive current amplitude depends entirely on the capacity of the capacitor, and the current phase always leads the voltage by 90° and is not affected by load changes, it provides a more stable and reliable basis for judging the commissioning of power equipment.

[0077] When testing the phase quantity, connect the voltage and current to the intelligent three-phase phase volt-ampere meter and select the reference voltage U a As a reference, record the three-phase current (I a , I b , I c ) size and angle, draw the measured current and voltage two-dimensional relationship into the XY coordinate system, and check I a and U a The angle between the two is correct. a Ahead I b The angle is 120 degrees, I b Ahead I c The angle is 120 degrees. At the same time, check that the sampling of the protection device is correct and the start-up differential flow is displayed correctly, further confirming the correctness of the start-up differential phase quantity test.

[0078] From the above description, it can be seen that the method for measuring the phase quantity of the starting and standby transformer under load provided in the present application can complete the phase quantity test of each unit of the starting and standby transformer plant at one time, which greatly shortens the test time. After the polarity of the current transformers and the related protection differential current of the booster station and the starting and standby transformer are correctly re-measured, the starting and standby transformer protection can be put into operation as soon as possible, that is, the booster station and the starting and standby transformer can be started and put into production, ensuring the efficiency of the test and providing safety guarantee for the system trial operation of the units.

[0079] The following will separately elaborate on steps S101 to S103 in detail.

[0080] Step S101: Control the start-up and standby transformer system to perform voltage transformer phase checking and capacitor bank charging.

[0081] It can be understood that in order to perform phasor testing on the start-up and standby transformer system, it is necessary to pre-complete the phase checking of the voltage transformers in the start-up and standby transformer system and complete the capacitor bank charging.

[0082] Figure 2 This is a specific embodiment of the method for realizing the measurement of phasors with load during the power transmission of the start-up and standby transformer in the embodiments of the present application.

[0083] In one embodiment, referring to Figure 2 , the control of the start-up and standby transformer system to perform voltage transformer phase checking and capacitor bank charging includes:

[0084] S201: After determining that the insulation state of the primary equipment is normal, control the closing of the standby incoming line switches of each section;

[0085] S202: Perform voltage transformer phase checking on the high-voltage side voltage of the start-up and standby transformer and the incoming line voltages of each section;

[0086] S203: Control the closing of the capacitor bank switch to charge the capacitor bank.

[0087] It can be understood that before the start-up and standby transformer and the plant receiving power, it is necessary to calculate the load capacity according to the load carried by the start-up and standby transformer in the booster station. For example, if the capacity of the start-up and standby transformer is S = 80 MVA, the high-voltage side voltage level is U1 = 525 kV, the high-voltage side CT transformation ratio is n1 = 4000 / 1, the low-voltage side voltage level is U2 = 10.5 kV, and the low-voltage side CT transformation ratio is n2 = 4000 / 1, then in order to ensure that the load current should meet the accuracy requirements of the test instrument, the secondary value of the high-voltage side current transformer should be greater than 10 mA. According to the high-voltage side CT transformation ratio, the high-voltage side primary current is calculated as I1 = n1 × 10 mA = 4000 × 10 mA = 40 A, and then the high-voltage side primary current is converted to the low-voltage side primary current as Since the low-voltage side has 4 branches, the primary current required for each branch is According to the primary current of 500 A required for each branch on the low-voltage side, according to the capacitor capacity The actually installed capacitor bank capacity on site is 10000 Kavr. Configure the capacitor bank in advance according to the calculated load capacity, connect the capacitors to the corresponding switches of each section of 10 kV respectively, and check that the capacitor bank is normal.

[0088] Next, close the isolating switch on the high-voltage side of the start-up and standby transformer, and then close the start-up and standby transformer side switch at the step-up substation. Conduct the first charging of the start-up and standby transformer, check the conditions of the primary and secondary equipment after energization, and check whether the insulation of the newly commissioned primary equipment is in good condition. Then, conduct voltage transformer phase verification for the system voltage on the high-voltage side of the start-up and standby transformer and the voltages of each section on the low-voltage side of the start-up and standby transformer.

[0089] Use an AC voltmeter to measure the secondary voltage of phase A on the high-voltage side against the secondary voltage of phase A on the low-voltage side to determine the actual wiring group of the primary side of the transformer. Then, record the group marking on the transformer nameplate and compare it with the setting sheet printed during the verification of the start-up and standby transformer. They should be consistent. When the secondary voltage difference between the two sides of phase A is close to 0V, the wiring groups on both sides are the same. When the secondary voltage difference between the two sides of phase A is close to 30V, one side is in delta connection.

[0090] Next, conduct phase verification between the voltage on the high-voltage side of the start-up and standby transformer and the PTs of each incoming line at 10kV. Specifically, close the standby incoming line switches of each section at 10kV for Unit 1 respectively to charge each section of the 10kV busbar, and conduct phase verification between the PT of the 10kV busbar and the PT of the 10kV standby incoming line. Close the standby incoming line switches of each section at 10kV for Unit 2 respectively to charge the 10kV busbar, and conduct phase verification between the PT of the 10kV busbar and the PT of the 10kV standby incoming line. Close the capacitor bank switches of each section at 10kV for Unit 1 respectively to charge the capacitor bank. Close the capacitor bank switches of each section at 10kV for Unit 2 respectively to charge the capacitor bank.

[0091] As can be seen from the above description, the method for measuring phase vectors during the power transmission of the start-up and standby transformer provided in this application can control the start-up and standby transformer system to conduct voltage transformer phase verification and capacitor bank charging.

[0092] Step S102: After the voltage transformer phase verification is correct and the capacitor charging is completed, control the closing of the start-up and standby transformer side switch, and conduct the test of the secondary current and phase of the differential protection under the closing of the start-up and standby transformer side switch to obtain the first test result; wherein, the first test result includes the phase vectors of the start-up and standby transformer.

[0093] It can be understood that after the voltage transformer phase verification is correct and the capacitor charging is completed, the closing of the start-up and standby transformer side switch can be controlled, and the test of the secondary current and phase of the differential protection under the closing of the start-up and standby transformer side switch can be conducted.

[0094] Figure 3 This is a specific embodiment of the method for realizing the power transmission of the start-up and standby transformer with load phase measurement in the embodiments of this application.

[0095] In one embodiment, refer to Figure 3, the first test result further includes the transformation ratio of the current transformer, the current direction, the load-side measured current phasor and phase, and the current phase of the corresponding phase on the power supply side; performing the test on the differential protection secondary current and phase under the closing of the start-up and standby transformer side switch to obtain the first test result, including:

[0096] S301: Measure the current value of the equipment related to the secondary current and the phase angle of the reference phasor to obtain the phasor of the start-up and standby transformer;

[0097] S302: Calculate the differential current according to the current value and the phase angle of the reference phasor;

[0098] S303: When the differential current meets the threshold, check the transformation ratio, current direction, load-side measured current phasor and phase, and the current phase of the corresponding phase on the power supply side of each current transformer.

[0099] It can be understood that in this step, the capacitor load current connected to 10 kV is used to check the transformer protection, T-zone protection, and 10 kV related protection of the start-up and standby transformer. For the test of the secondary current and phase of each side of the differential protection, use a phase meter to test all relevant current values and the phase angle with the reference phasor of the current circuits on the protection cabinets and switch cabinets where all secondary currents arrive, check that the secondary current circuit is correct, the phase currents of each phase should be in positive phase sequence, the phase difference is 120 degrees, and the current should meet the setting requirements.

[0100] Next, enter the differential protection menu of the protection device in the start-up and standby transformer power protection cabinet, check that the differential current displayed on the differential protection panel should be close to 0, the differential current should not be greater than 0.1 A, and record it. Next, perform secondary current tests on metering equipment, measuring equipment, standby groups, and other related equipment, use a phase meter to test all relevant current values and the phase angle with the reference phasor of the current circuits on the protection cabinets and switch cabinets where all secondary currents arrive, check that the secondary current circuit is correct, and the current should meet the metering and measurement requirements. Next, perform the correctness check of the transformation ratio of each group of circuit transformers and the differential current of the differential protection, use the data obtained from the test to analyze and check that the CT transformation ratio is correct, the current direction is correct, and the phase difference between the load-side measured current phasor of the differential protection and the current phase of the corresponding phase on the power supply side is 180 degrees.

[0101] After completing the phasor test, disconnect the start-up and standby transformer side switch in the booster station.

[0102] As can be seen from the above description, the method for measuring the phasor with the start-up and standby transformer energized provided by this application can perform the test on the differential protection secondary current and phase under the closing of the start-up and standby transformer side switch to obtain the first test result.

[0103] Figure 4 This is a specific embodiment of the method for realizing the phasor measurement with the start-up and standby transformer energized in the embodiment of this application.

[0104] In one embodiment, referring to Figure 4 , determining whether the start-up and standby transformer can be safely put into operation according to the current, voltage, phase of the pre-calculated current transformer and the first test result includes:

[0105] S401: Calculate the required current, required voltage and required phase of the current transformer according to the current loop structure of the start-up and standby transformer system and the capacity of the capacitor bank;

[0106] S402: Judge whether the secondary polarity of the current transformer is correct according to the required current, required voltage and required phase, the power flow direction of the start-up and standby transformer system and the first test result, so as to determine whether the start-up and standby transformer can be safely put into operation.

[0107] It can be understood that in the embodiment of the present application, for the installation of capacitors in the 10kV standby load switch cabinet, the current load method of capacitors is adopted. According to the capacitor capacity and current loop information, the secondary amplitude of the CT used for the corresponding protection and the phase relationship between current and voltage are calculated. According to the capacity of each section of capacitors on the low-voltage side S = 10000Kvar, the voltage level of the high-voltage side of the start-up and standby transformer U1 = 525kV, the transformation ratio of the differential CT on the high-voltage side of the start-up and standby transformer protection is n1 = 600 / 1, the voltage level of the low-voltage side of the start-up and standby transformer U2 = 10.5kV, and the transformation ratio of the differential CT on the low-voltage side of the start-up and standby transformer protection is n2 = 4000 / 1, the secondary current of each section on the low-voltage side of the start-up and standby transformer The primary current of each section on the low-voltage side of the start-up and standby transformer is I 低 = I ； 低 ×n2 = 137mA×4000 = 548A, and the primary current of the high-voltage side of the start-up and standby transformer is Then, according to the transformation ratio of the differential CT on the high-voltage side of the start-up and standby transformer protection n1 = 600 / 1, the secondary amplitude of the CT is calculated as Since the load is a capacitive load of the capacitor, the current leads the voltage by 90°. Therefore, taking the voltage of phase A on the low-voltage side as the reference, the phase of the current of phase A on the low-voltage side is measured as 90°, and the currents of other phases should be 120° out of phase with the current of phase A; combined with the power flow direction, predict which quadrant of the phasor diagram the currents of each phase measured by the phase meter are located in. If it is a capacitive load, the current of phase A should be in the second quadrant of the phasor diagram. If it is an inductive load, the current of phase A should be in the first quadrant of the phasor diagram; after the start-up and standby transformer is powered on, use the capacitor bank as the load to detect the phasor method, and make a phasor diagram according to the test data for verification; taking the polarity of the differential protection of the start-up and standby transformer as an example, the phase difference between the CT on the low-voltage side and the voltage is 90°. According to the principle of differential protection, the angles of the CTs on both sides should differ by 180°. Therefore, the phase difference between the CT on the high-voltage side and the voltage is 270°, so as to judge whether the secondary polarity of the current transformer is correct. Refer to Figure 14 as shown.

[0108] Since the amplitude of the capacitive current depends entirely on the capacitance of the capacitor, and the current phase always leads the voltage by 90°, which is not affected by load changes, it provides a more stable and reliable basis for the commissioning of power equipment.

[0109] As can be seen from the above description, the method for measuring the phase vector of the start-up and standby transformer during power transmission with load provided by this application can determine whether the start-up and standby transformer can be safely put into operation based on the current, voltage, phase of the current transformer calculated in advance, and the first test result.

[0110] Figure 5 This is a specific embodiment of the method for realizing the phase vector measurement of the start-up and standby transformer during power transmission with load in the embodiments of this application.

[0111] In one embodiment, referring to Figure 5 , the method for measuring the phase vector of the start-up and standby transformer during power transmission with load further includes:

[0112] S501: Control the switch in the start-up and standby transformer to close, and perform the test on the secondary current and phase of the differential protection under the closing of the switch in the start-up and standby transformer to obtain the second test result;

[0113] S502: Judge whether the secondary polarity of the current transformer of the switch in the start-up and standby transformer is correct according to the second test result. If it is correct, put the start-up and standby transformer into operation.

[0114] It can be understood that after completing the test on the secondary current and phase of the differential protection under the closing of the side switch of the start-up and standby transformer, the test on the secondary current and phase of the differential protection under the closing of the switch in the start-up and standby transformer can be further carried out. Combining the results of the two tests, judge whether the secondary polarity of the current transformer of the switch in the start-up and standby transformer is correct.

[0115] Specifically, close the switch in the start-up and standby transformer of the step-up substation, and use the load current to check (CT phase measurement) the differential protection of the start-up and standby transformer and the three-side protection of the T area. The specific CT phase-checking method is the same as the CT phase-checking method when performing the test on the secondary current and phase of the differential protection under the closing of the side switch of the start-up and standby transformer.

[0116] Open the capacitor bank switches of each section of 10kV of Unit 1 and Unit 2 in sequence; open the standby incoming line switches of each section of 10kV of Unit 1 and Unit 2 in sequence; transfer all switches from hot standby to cold standby, and remove the capacitors of each section of 10kV; after the above work is completed, the start-up and standby transformer is charged again for 24-hour trial operation; thus, the work of measuring the phase vector of the start-up and standby transformer with load is all completed.

[0117] As can be seen from the above description, the method for measuring the phase vector of the start-up and standby transformer during power transmission with load provided by this application can perform the test on the secondary current and phase of the differential protection under the closing of the switch in the start-up and standby transformer, and judge whether the secondary polarity of the current transformer of the switch in the start-up and standby transformer is correct.

[0118] To more clearly illustrate the method provided by this application, a numerical example is given below. See Figure 12 and Figure 13 as shown

[0119] First, the preparatory work before the test.

[0120] (1) Estimate the load capacity according to the load carried by the startup and standby transformer 51B in the booster station;

[0121] (2) Configure capacitor banks in advance according to the estimated load capacity;

[0122] (3) Connect the capacitors in the capacitor bank to the corresponding 10 kV switches, and conduct inspection work on the capacitors;

[0123] (4) The installed capacity of the startup and standby transformer capacitors for the 1000 MW unit project is 40000 kvar.

[0124] Second, the on-site measurement method for the phase vector of the load with capacitors on the startup and standby transformer.

[0125] (1) The booster station NCS closes the 50216 disconnecting switch;

[0126] (2) The 5021 switch in the booster station is changed from cold standby to hot standby, and the charging overcurrent protection of this switch is put into operation as required;

[0127] (3) The 5021 switch in the booster station is changed from hot standby to operation, and the 51B startup and standby transformer is charged for the first time. Closely monitor and inspect the conditions of the primary and secondary equipment after pressurization, measure and record the magnetizing inrush current and transient waveforms, and check whether the insulation of the newly commissioned primary equipment is in good condition and whether the wiring is correct; The CVT on the high-voltage side of the 51B startup and standby transformer in the booster station is phase-checked with the CVT on the 500 kV #1M busbar.

[0128] (4) The CVT on the high-voltage side of the startup and standby transformer is phase-checked with the PTs of the 10 kV 1A and 10 kV 1B incoming lines of the 1F generator, and the CVT on the high-voltage side of the startup and standby transformer is phase-checked with the PTs of the 10 kV 2A and 10 kV 2B incoming lines of the 2F generator;

[0129] (5) The 10 kV switches 10BBA01, 10BBB01, 20BBA01, 20BBB01, 10BBA05, 10BBB05, 20BBA05, and 20BBB05 on the low-voltage side of the startup and standby transformer are sequentially changed from cold standby to hot standby;

[0130] (6) The DCS closes the 10BBA01 switch of the 1st unit and charges the 10 kV 1A busbar, and conducts phase-checking between the PT of the 10 kV 1A busbar and the standby incoming PT of the 10 kV 1A;

[0131] (7) The DCS closes the 10BBB01 switch of Unit 1 to charge the 10kV 1B busbar and perform phase checking between the PT of the 10kV 1B busbar and the standby incoming line PT of 10kV 1B;

[0132] (8) The DCS closes the 20BBA01 switch of Unit 2 to charge the 10kV 2A busbar and perform phase checking between the PT of the 10kV 2A busbar and the standby incoming line PT of 10kV 2A;

[0133] (9) The DCS closes the 20BBB01 switch of Unit 2 to charge the 10kV 2B busbar and perform phase checking between the PT of the 10kV 2B busbar and the standby incoming line PT of 10kV 2B;

[0134] (10) The DCS closes the 10BBA05 switch of Unit 1 to charge the #1 capacitor bank, record the 500kV busbar voltage, and record the operation of the lightning arrester;

[0135] (11) The DCS closes the 10BBB05 switch of Unit 1 to charge the #2 capacitor bank, record the 500kV busbar voltage, and record the operation of the lightning arrester;

[0136] (12) The DCS closes the 20BBA05 switch of Unit 2 to charge the #3 capacitor bank, record the 500kV busbar voltage, and record the operation of the lightning arrester;

[0137] (13) The DCS closes the 20BBB05 switch of Unit 2 to charge the #4 capacitor bank, record the 500kV busbar voltage, and the step-up substation uses the capacitor load current to check the protection of the 51B startup and standby transformer, the T zone protection, and the relevant 10kV protection;

[0138] (14) The 5022 switch in the cold standby state of the step-up substation is transferred to the hot standby state, and the charging overcurrent protection of this switch is put into operation as required;

[0139] (15) The 5022 switch in the hot standby state of the step-up substation is transferred to the operating state;

[0140] (16) The 5021 switch in the operating state of the step-up substation is transferred to the hot standby state, and the charging overcurrent protection of this switch is withdrawn as required;

[0141] (17) The step-up substation uses the load current to check the protection of the 51B startup and standby transformer and the T zone protection;

[0142] (18) The DCS sequentially opens the 20BBB05, 20BBA05, 10BBB05, and 10BBA05 switches;

[0143] (19) The DCS sequentially opens the 20BBB01, 20BBA01, 10BBB01, and 10BBA01 switches;

[0144] (20) Transfer the 10 kV switches 20BBB05, 20BBA05, 10BBB05, 10BBA05, 20BBB01, 20BBA01, 10BBB01, and 10BBA01 from hot standby to cold standby.

[0145] (21) Transfer the operation of the 5022 switch in the step-up substation to hot standby, and withdraw the overcurrent protection for charging of this switch as required.

[0146] (22) Use the 5022 switch in the step-up substation to switch the 51B startup standby transformer on and off twice. Each time, the energized time shall not be less than 5 minutes, and the operating interval time is 5 minutes. Closely monitor and check the conditions of the primary and secondary equipment after pressurization, measure and record the magnetizing inrush current and transient waveforms, and check whether the insulation condition of the newly commissioned primary equipment is good.

[0147] (23) Use the 5021 switch in the step-up substation to switch the 51B startup standby transformer on and off twice. Each time, the energized time shall not be less than 5 minutes, and the operating interval time is 5 minutes. Closely monitor and check the conditions of the primary and secondary equipment after pressurization, measure and record the magnetizing inrush current and transient waveforms, and check whether the insulation condition of the newly commissioned primary equipment is good.

[0148] (24) Transfer the 5021 and 5022 switches in the step-up substation from hot standby to operation, and input the operating protection setting values for the 5021 and 5022 switches and the 51B startup standby transformer as required.

[0149] (25) After the above work is completed, the 51B startup standby transformer is energized for 24-hour trial operation; thus, all the work of measuring the phase vectors with the startup standby transformer under load is completed.

[0150] (26) Phase vector test records (the 1A and 1B branches of the No. 1 generator and the 2A and 2B branches of the No. 2 generator are all capacitive loads). (See Table 1)

[0151] Table 1 Phase vector test records

[0152]

[0153]

[0154]

[0155] Since the load is a capacitive load of a capacitor, the current leads the voltage by 90°. Therefore, taking the voltage of phase A on the low-voltage side as the reference, the phase of the current of phase A on the low-voltage side is measured to be 90°, and the currents of the three phases A, B, and C are 120° out of phase with each other; the current of phase A of the capacitive load should be in the second quadrant of the phasor diagram; taking the polarity of the differential protection of the startup standby transformer as an example, the phase difference between the CT on the low-voltage side and the voltage is 90°. According to the principle of differential protection, the angles of the CTs on both sides should differ by 180°. Therefore, the phase difference between the CT on the high-voltage side and the voltage is 270°, and this is used to judge whether the secondary polarity of the current transformer is correct.

[0156] It can be seen that the relevant protection of the startup and standby transformer has passed the phasor test in the system test, and the phase, phase sequence, polarity, and transformation ratio of the CT and PT are correct, so it can be put into operation.

[0157] Based on the same inventive concept, the embodiment of the present application also provides a device for measuring phasors during the power transmission of the startup and standby transformer with load, which can be used to implement the method described in the above embodiment, as described in the following embodiment. Since the principle of solving problems by the device for measuring phasors during the power transmission of the startup and standby transformer with load is similar to that of the method for measuring phasors during the power transmission of the startup and standby transformer with load, the implementation of the device for measuring phasors during the power transmission of the startup and standby transformer with load can refer to the implementation of the method for determining based on software performance benchmarks, and the repeated parts will not be described again. Hereinafter, the term "unit" or "module" can be a combination of software and / or hardware that can achieve a predetermined function. Although the system described in the following embodiments is preferably implemented in software, implementation in hardware, or a combination of software and hardware is also possible and contemplated.

[0158] In one embodiment, referring to Figure 6 , in order to be able to replace the plant load to achieve the purpose of measuring phasors during the power transmission of the startup and standby transformer with load, the present application provides a device for measuring phasors during the power transmission of the startup and standby transformer with load, including:

[0159] A phase verification and charging unit 601, configured to control the startup and standby transformer system to perform voltage transformer phase verification and capacitor bank charging;

[0160] A first phasor test unit 602, configured to control the closing of the startup and standby transformer side switch after the voltage transformer phase verification is correct and the capacitor charging is completed, and perform a test on the differential protection secondary current and phase under the closing of the startup and standby transformer side switch to obtain a first test result; wherein, the first test result includes the phasor of the startup and standby transformer;

[0161] A first commissioning safety detection unit 603, configured to determine whether the startup and standby transformer can be safely put into operation according to the current, voltage, phase of the current transformer calculated in advance and the first test result.

[0162] In one embodiment, referring to Figure 7 , the phase verification and charging unit 601 includes:

[0163] An incoming line closing control module 701, configured to control the closing of each section of standby incoming line switch after determining that the insulation state of the primary equipment is normal;

[0164] A voltage phase verification module 702, configured to perform voltage transformer phase verification on the high-voltage side voltage of the startup and standby transformer and the incoming line voltages of each section;

[0165] A capacitor charging module 703, configured to control the closing of the capacitor bank switch to charge the capacitor bank.

[0166] In one embodiment, refer to Figure 8 The first test result further includes the transformation ratio of the current transformer, the current direction, the load-side measured current phasor and phase, and the current phase of the corresponding phase on the power supply side; the first phasor test unit 602 includes:

[0167] A phasor measurement module 801 for measuring the current value of the secondary current-related device and the phase angle of the reference phasor to obtain the phasor of the startup and standby transformer;

[0168] A differential current calculation module 802 for calculating the differential current based on the current value and the phase angle of the reference phasor;

[0169] A current measurement module 803 for checking the transformation ratio, current direction, load-side measured current phasor and phase, and the current phase of the corresponding phase on the power supply side of each current transformer when the differential current meets the threshold.

[0170] In one embodiment, refer to Figure 9 The commissioning safety detection unit 603 includes:

[0171] A demand calculation module 901 for calculating the demand current, demand voltage and demand phase of the current transformer according to the current loop structure of the startup and standby transformer system and the capacity of the capacitor bank;

[0172] A commissioning safety detection module 902 for judging whether the secondary polarity of the current transformer is correct according to the demand current, demand voltage and demand phase, the power flow direction of the startup and standby transformer system and the first test result, so as to determine whether the startup and standby transformer can be safely commissioned.

[0173] In one embodiment, refer to Figure 10 The device for measuring phasors when the startup and standby transformer is energized and under load further includes:

[0174] A second phasor test unit 1001 for controlling the closing of the switch in the startup and standby transformer and testing the differential protection secondary current and phase under the closing of the switch in the startup and standby transformer to obtain a second test result;

[0175] A second commissioning safety detection unit 1002 for judging whether the secondary polarity of the current transformer of the switch in the startup and standby transformer is correct according to the second test result. If so, the startup and standby transformer is put into operation.

[0176] From the hardware level, in order to be able to replace the plant load to achieve the purpose of measuring phasors when the startup and standby transformer is energized and under load, this application provides an embodiment of an electronic device for implementing all or part of the content in the method for measuring phasors when the startup and standby transformer is energized and under load. The electronic device specifically includes the following content:

[0177] A processor, a memory, a communications interface, and a bus; wherein, the processor, the memory, and the communications interface complete communication with each other through the bus; the communications interface is used to implement information transmission between the device for measuring phase vectors during start-up, standby power transmission, and load connection and related devices such as a core business system, a user terminal, and a related database, etc.; this logic controller can be a desktop computer, a tablet computer, a mobile terminal, etc., and this embodiment is not limited thereto. In this embodiment, this logic controller can be implemented with reference to the embodiments of the method for measuring phase vectors during start-up, standby power transmission, and load connection in the embodiments, as well as the embodiments of the device for measuring phase vectors during start-up, standby power transmission, and load connection. The content is incorporated herein, and the repeated parts will not be elaborated again.

[0178] It can be understood that the user terminal may include a smart phone, a tablet electronic device, an Internet set-top box, a portable computer, a desktop computer, a personal digital assistant (PDA), a vehicle-mounted device, a smart wearable device, etc. Among them, the smart wearable device may include smart glasses, a smart watch, a smart bracelet, etc.

[0179] In practical applications, part of the method for measuring phase vectors during start-up, standby power transmission, and load connection can be executed on the electronic device side as described above, or all operations can be completed in the client device. Specifically, it can be selected according to the processing capacity of the client device and the limitations of the user usage scenario, etc. This application does not make any limitations in this regard. If all operations are completed in the client device, the client device may further include a processor.

[0180] The above-mentioned client device may have a communication module (i.e., a communication unit), and can be communicatively connected to a remote server to achieve data transmission with the server. The server may include a server on the task scheduling center side, and in other implementation scenarios, it may also include a server of an intermediate platform, such as a server of a third-party server platform communicatively linked to the task scheduling center server. The server may include a single computer device, or may include a server cluster composed of multiple servers, or a server structure of a distributed device.

[0181] Figure 11 This is a schematic block diagram of the system composition of the electronic device 9600 according to an embodiment of the present application. As Figure 11 shown, the electronic device 9600 may include a central processing unit 9100 and a memory 9140; the memory 9140 is coupled to the central processing unit 9100. It should be noted that this Figure 11 is exemplary; other types of structures can also be used to supplement or replace this structure to achieve telecommunication functions or other functions.

[0182] In one embodiment, the method function of starting up the transformer with load phase measurement can be integrated into the central processor 9100. The central processor 9100 can be configured to perform the following control:

[0183] S101: Control the standby transformer system to charge the voltage transformer phase and capacitor bank;

[0184] S102: After the voltage transformer phase is correct and the capacitor is charged, the start-up and standby transformer switch is controlled to close, and the secondary current and phase of the differential protection under the start-up and standby transformer switch is tested to obtain a first test result; wherein the first test result includes the phase quantity of the start-up and standby transformer;

[0185] S103: Determine whether the standby transformer can be safely put into operation according to the pre-calculated current, voltage, phase of the current transformer and the first test result.

[0186] From the above description, it can be seen that the method for measuring the phase quantity of the starting and standby transformer under load provided in the present application can complete the phase quantity test of each unit of the starting and standby transformer plant at one time, which greatly shortens the test time. After the polarity of the current transformers and the related protection differential current of the booster station and the starting and standby transformer are correctly re-measured, the starting and standby transformer protection can be put into operation as soon as possible, that is, the booster station and the starting and standby transformer can be started and put into production, ensuring the efficiency of the test and providing safety guarantee for the system trial operation of the units.

[0187] In another embodiment, the device for measuring the phase quantity of the power transformer with load can be configured separately from the central processing unit 9100. For example, the device for measuring the phase quantity of the power transformer with load of the data composite transmission device can be configured as a chip connected to the central processing unit 9100, and the function of the method for measuring the phase quantity of the power transformer with load can be realized through the control of the central processing unit.

[0188] like Figure 11 As shown, the electronic device 9600 may also include: a communication module 9110, an input unit 9120, an audio processor 9130, a display 9160, and a power supply 9170. It is worth noting that the electronic device 9600 does not necessarily have to include Figure 11 In addition, the electronic device 9600 may also include Figure 11 For components not shown, reference may be made to the prior art.

[0189] like Figure 11 As shown, the central processing unit 9100 is sometimes also referred to as a controller or an operation control, and may include a microprocessor or other processor device and / or logic device. The central processing unit 9100 receives input and controls the operation of various components of the electronic device 9600.

[0190] Among them, the memory 9140 can be, for example, one or more of a buffer, a flash memory, a hard drive, a removable medium, a volatile memory, a non-volatile memory, or other suitable devices. The above information related to failures can be stored, and in addition, a program for executing relevant information can also be stored. And the central processing unit 9100 can execute the program stored in the memory 9140 to achieve information storage or processing, etc.

[0191] The input unit 9120 provides input to the central processing unit 9100. The input unit 9120 is, for example, a key or a touch input device. The power supply 9170 is used to supply power to the electronic device 9600. The display 9160 is used to display display objects such as images and texts. The display can be, for example, an LCD display, but is not limited thereto.

[0192] The memory 9140 can be a solid-state memory. For example, a read-only memory (ROM), a random access memory (RAM), a SIM card, etc. It can also be a memory that stores information even when power is off, can be selectively erased and has more data. An example of this memory is sometimes called an EPROM, etc. The memory 9140 can also be some other type of device. The memory 9140 includes a buffer memory 9141 (sometimes called a buffer). The memory 9140 can include an application / function storage unit 9142, which is used to store application programs and function programs or the processes for operating the electronic device 9600 through the central processing unit 9100.

[0193] The memory 9140 can also include a data storage unit 9143, which is used to store data, such as contacts, digital data, pictures, sounds, and / or any other data used by the electronic device. The driver storage unit 9144 of the memory 9140 can include various drivers of the electronic device for communication functions and / or for performing other functions of the electronic device (such as a messaging application, an address book application, etc.).

[0194] The communication module 9110 is a transmitter / receiver 9110 that transmits and receives signals via the antenna 9111. The communication module (transmitter / receiver) 9110 is coupled to the central processing unit 9100 to provide input signals and receive output signals, which can be the same as in the case of a conventional mobile communication terminal.

[0195] Based on different communication technologies, in the same electronic device, multiple communication modules 9110 can be provided, such as a cellular network module, a Bluetooth module, and / or a wireless local area network module, etc. The communication module (transmitter / receiver) 9110 is also coupled to a speaker 9131 and a microphone 9132 via an audio processor 9130 to provide an audio output via the speaker 9131 and receive an audio input from the microphone 9132, so as to implement normal telecommunication functions. The audio processor 9130 can include any suitable buffers, decoders, amplifiers, etc. Additionally, the audio processor 9130 is also coupled to a central processor 9100, so that recording can be performed on the local device through the microphone 9132, and the sound stored on the local device can be played through the speaker 9131.

[0196] An embodiment of the present application also provides a computer-readable storage medium capable of implementing all steps in the method for measuring phasors with load during start-up, standby power supply transformation, and power transmission with the execution subject being a server or a client in the above embodiments. A computer program is stored on the computer-readable storage medium, and when the computer program is executed by a processor, all steps in the method for measuring phasors with load during start-up, standby power supply transformation, and power transmission with the execution subject being a server or a client in the above embodiments are implemented. For example, when the processor executes the computer program, the following steps are implemented:

[0197] S101: Control the start-up and standby power transformation system to perform voltage transformer phase checking and capacitor bank charging;

[0198] S102: After the voltage transformer phase checking is correct and the capacitor charging is completed, control the closing of the start-up and standby transformer side switch, and perform a test on the secondary current and phase of the differential protection under the closing of the start-up and standby transformer side switch to obtain a first test result; wherein, the first test result includes the phasor of the start-up and standby transformer;

[0199] S103: Determine whether the start-up and standby transformer can be safely put into operation according to the pre-calculated current, voltage, phase of the current transformer, and the first test result.

[0200] As can be seen from the above description, the method for measuring phasors with load during start-up, standby power supply transformation, and power transmission provided by the present application can complete the phasor test of each unit in the start-up and standby transformer plant in one go, greatly shortening the test time. After the polarities of the current transformers in the step-up substation and the start-up and standby transformer and the relevant protection differential current are retested correctly, the start-up and standby transformer protection can be put into operation as soon as possible, that is, the step-up substation and the start-up and standby transformer are started and put into production, ensuring the high efficiency of the test and providing a safety guarantee for the subsystem commissioning of the unit.

[0201] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, an apparatus, or a computer program product. Therefore, the present invention can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk memory, CD-ROM, optical memory, etc.) that contain computer-usable program code.

[0202] The present invention is described with reference to the flowcharts and / or block diagrams of methods, apparatus (devices), and computer program products according to embodiments of the present invention. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of flows and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing devices generate a device for implementing the functions specified in Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0203] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, such that the instructions stored in the computer-readable memory generate a manufactured article including an instruction device that implements the functions specified in Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0204] These computer program instructions can also be loaded onto a computer or other programmable data processing device, such that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process, and thus the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0205] Specific embodiments are applied in the present invention to elaborate on the principles and implementation manners of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A method for measuring phase quantities with load during the power transmission of the startup and standby transformer, characterized in that, Including: Controlling the start-up and standby transformer system to perform voltage transformer phase verification and capacitor bank charging; After the voltage transformer phase verification is correct and the capacitor charging is completed, controlling the closing of the start-up and standby transformer side switch, and performing tests on the secondary current and phase of the differential protection under the closing of the start-up and standby transformer side switch to obtain a first test result; wherein, the first test result includes the phasor of the start-up and standby transformer, the transformation ratio of the current transformer, the current direction, the load-side current phasor and phase, and the current phase of the corresponding phase on the power supply side; the performing tests on the secondary current and phase of the differential protection under the closing of the start-up and standby transformer side switch to obtain a first test result includes: measuring the current value of the equipment related to the secondary current and the phase angle of the reference phasor to obtain the phasor of the start-up and standby transformer; calculating the differential current according to the current value and the phase angle of the reference phasor; when the differential current meets the threshold, checking the transformation ratio, current direction, load-side current phasor and phase, and the current phase of the corresponding phase on the power supply side of each current transformer; Determining whether the start-up and standby transformer can be safely put into operation according to the pre-calculated current, voltage, phase of the current transformer and the first test result.

2. The method for measuring phase quantities under load during the power transmission of the startup and standby transformer according to claim 1, wherein The controlling the start-up and standby transformer system to perform voltage transformer phase verification and capacitor bank charging includes: After determining that the insulation state of the primary equipment is normal, controlling the closing of each section of the standby incoming line switch; Performing voltage transformer phase verification on the high-voltage side voltage of the start-up and standby transformer and the incoming line voltages of each section; Controlling the closing of the capacitor bank switch to charge the capacitor bank.

3. The method for measuring phase quantities with load when the start-up and standby transformer is powered on according to claim 1, wherein, The determining whether the start-up and standby transformer can be safely put into operation according to the pre-calculated current, voltage, phase of the current transformer and the first test result includes: Calculating the required current, required voltage and required phase of the current transformer according to the current loop structure of the start-up and standby transformer system and the capacity of the capacitor bank; Judging whether the secondary polarity of the current transformer is correct according to the required current, required voltage and required phase, the power flow direction of the start-up and standby transformer system and the first test result to determine whether the start-up and standby transformer can be safely put into operation.

4. The method for measuring phase quantities with load when starting-up and standby transformers are put into power supply according to claim 1, wherein, Also including: Controlling the closing of the switch in the start-up and standby transformer, and performing tests on the secondary current and phase of the differential protection under the closing of the switch in the start-up and standby transformer to obtain a second test result; Judging whether the secondary polarity of the current transformer of the switch in the start-up and standby transformer is correct according to the second test result, and if so, putting the start-up and standby transformer into operation.

5. A device for measuring phase quantities with load during the power transmission of the startup and standby transformer, characterized in that, Including: A phase verification and charging unit for controlling the start-up and standby transformer system to perform voltage transformer phase verification and capacitor bank charging; The first phasor test unit is used to control the closing of the start-up and standby transformer side switch after the voltage transformer phase verification is correct and the capacitor charging is completed, and to test the differential protection secondary current and phase under the closing of the start-up and standby transformer side switch, so as to obtain the first test result; wherein, the first test result includes the phasor of the start-up and standby transformer, the transformation ratio of the current transformer, the current direction, the load-side measured current phasor and phase, and the current phase of the corresponding phase on the power supply side; the first phasor test unit includes: a phasor measurement module, which is used to measure the current value of the equipment related to the secondary current and the phase angle of the reference phasor to obtain the phasor of the start-up and standby transformer; a differential current calculation module, which is used to calculate the differential current based on the current value and the phase angle of the reference phasor; a current measurement module, which is used to check the transformation ratio of each current transformer, the current direction, the load-side measured current phasor and phase, and the current phase of the corresponding phase on the power supply side when the differential current meets the threshold value. The first commissioning safety detection unit is used to determine whether the start-up and standby transformer can be safely commissioned according to the current, voltage, phase of the current transformer calculated in advance and the first test result.

6. The device for measuring phase quantities under load during start-up and standby transformer power transmission according to claim 5, characterized in that, The phase verification and charging unit includes: An incoming line closing control module, which is used to control the closing of each section of standby incoming line switch after determining that the insulation state of the primary equipment is normal. A voltage phase verification module, which is used to perform voltage transformer phase verification on the high-voltage side voltage of the start-up and standby transformer and the incoming line voltage of each section. A capacitor charging module, which is used to control the closing of the capacitor bank switch to charge the capacitor bank.

7. The device for measuring phase quantities with load when the start-up and standby transformers are powered on according to claim 5, characterized in that, The commissioning safety detection unit includes: A demand calculation module, which is used to calculate the required current, required voltage and required phase of the current transformer according to the current loop structure of the start-up and standby transformer system and the capacity of the capacitor bank. A commissioning safety detection module, which is used to judge whether the secondary polarity of the current transformer is correct according to the required current, required voltage and required phase, the power flow direction of the start-up and standby transformer system and the first test result, so as to determine whether the start-up and standby transformer can be safely commissioned.

8. The device for measuring phase quantities with load when the startup and standby transformers are energized according to claim 5, characterized in that, It also includes: The second phasor test unit is used to control the closing of the switch in the start-up and standby transformer, and to test the differential protection secondary current and phase under the closing of the switch in the start-up and standby transformer, so as to obtain the second test result. The second commissioning safety detection unit is used to judge whether the secondary polarity of the current transformer of the switch in the start-up and standby transformer is correct according to the second test result. If so, the start-up and standby transformer will be put into operation.

9. An electronic device, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, When the processor executes the program, it realizes the steps of the method for measuring the phasor with load during the power transmission of the start-up and standby transformer according to any one of claims 1 to 4.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it realizes the steps of the method for measuring the phasor with load during the power transmission of the start-up and standby transformer according to any one of claims 1 to 4.

11. A computer program product comprising a computer program / instructions, characterized in that, When the computer program / instructions are executed by the processor, it realizes the steps of the method for measuring the phasor with load during the power transmission of the start-up and standby transformer according to any one of claims 1 to 4.

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