CN112763801B - Method for measuring maximum switching phase angle of phase selection switching-on device of extra-high voltage converter station - Google Patents
Method for measuring maximum switching phase angle of phase selection switching-on device of extra-high voltage converter station Download PDFInfo
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R25/00—Arrangements for measuring phase angle between a voltage and a current or between voltages or currents
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- G—PHYSICS
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- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/327—Testing of circuit interrupters, switches or circuit-breakers
- G01R31/3271—Testing of circuit interrupters, switches or circuit-breakers of high voltage or medium voltage devices
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Abstract
The invention relates to the technical field of extra-high voltage power transmission, in particular to a method for measuring a maximum switching-on phase angle of a phase selection switching-on device of an extra-high voltage converter station, which comprises the following steps: carrying out a capacitive current test on a circuit breaker of an alternating current filter field of the converter station to obtain the maximum withstand inrush current of the converter station; building a PSCAD simulation model according to the electric main wiring and the actual parameters of the converter station; carrying out simulation operation according to a PSCAD simulation model, and calculating the inrush current condition of the alternating current filter field under different closing phase angles; and obtaining the maximum switching-on phase angle of the phase selection switching-on device of the extra-high voltage converter station based on the inrush current condition and according to the maximum tolerant inrush current. The invention provides a brand-new method for measuring the maximum switching-on phase angle of an alternating current filter field phase selection switching-on device of an extra-high voltage converter station, which considers the actual parameters and the running condition of the converter station and can more accurately measure the maximum switching-on phase angle of the phase selection switching-on device; the method provided by the invention is based on test data, the reliability is higher, and the measurement result is more accurate.
Description
Technical Field
The invention relates to the technical field of extra-high voltage power transmission, in particular to a method for measuring a maximum switching-on phase angle of a phase selection switching-on device of an extra-high voltage converter station.
Background
The direct current transmission has the advantages of large transmission power, low line cost, good control performance and the like, is an important means for high-voltage, large-capacity and long-distance power transmission and asynchronous networking in developed countries at present, and large-scale application of high-voltage direct current transmission is a necessary choice when large-scale western and east power transmission is realized in China. The alternating current filter is one of important devices in a direct current transmission system, and not only provides reactive power required by current conversion, but also can filter harmonic waves.
The phase selection closing device can control the circuit breaker to perform closing operation at a proper time, and effectively shortens the transient process generated by the input of the filter, so that the existing alternating current filter mostly adopts the circuit breaker with the phase selection closing function. The measurement of the maximum switching-on phase angle of the phase selection switching-on device is an important step for reducing switching-on inrush current within a reasonable range, and the existing measurement method of the maximum switching-on phase angle of the phase selection switching-on device is mostly based on the operation of other converter stations, and the operation parameters and the actual conditions of a target converter station are not fully considered, so that the measurement method is often inaccurate.
Therefore, it is necessary to design a more accurate method for measuring the maximum closing phase angle of the phase selection closing device.
Disclosure of Invention
The invention aims to at least solve one of the technical problems in the prior art and provides a method for measuring the maximum switching phase angle of a phase selection switching-on device of an extra-high voltage converter station.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows: a method for measuring a maximum switching phase angle of a phase selection switching-on device of an extra-high voltage converter station comprises the following steps:
step 2, building a PSCAD simulation model according to the electric main wiring and actual parameters of the converter station;
step 3, carrying out simulation operation according to the PSCAD simulation model, and calculating the inrush current condition of the alternating current filter field under different closing phase angles;
and 4, obtaining the maximum switching-on phase angle of the phase selection switching-on device of the extra-high voltage converter station based on the inrush current condition and according to the maximum tolerant inrush current.
Further, in step 1, the capacitive current test includes a basic test and a current open/close limit test, and the basic test is performed first, and then the current open/close limit test is performed.
Further, the basic test comprises a first test, the first test comprises 48 opening operation tests, the test conditions of the first test comprise that the operating voltage of the tripper adopts the highest voltage, the operating and breaking pressure adopts the lowest functional pressure, and the test current is 10-40 percent of the breaking current of the rated filter bank.
Further, the basic test comprises a second test, the second test comprises a 120-time switching-on/switching-off operation test, and the test conditions of the second test comprise that the operating voltage of the tripper adopts the highest voltage, the operating and switching-off pressures adopt the rated voltage, and the test current is more than 100 percent of the switching-off current of the rated filter bank.
Further, the basic test comprises a third test, the third test comprises a 12-time opening operation test, and the test conditions of the third test comprise that the operating voltage of the tripper adopts the highest voltage, the operating and breaking pressures adopt the rated pressure, and the test current is more than 100 percent of the breaking current of the rated filter bank.
Further, the current switching limit test includes 60 switching-on operation tests performed in a first polarity, 48 switching-on/off operation tests performed in a first polarity and switching-on operation performed in an unloaded state, 60 switching-on operation tests performed in a second polarity, and 48 switching-on/off operation tests performed in a second polarity and switching-on operation performed in an unloaded state.
Further, the test conditions of the current switching limit test include that the operating voltage of the release adopts the highest voltage, the operating and switching pressures adopt rated voltages, and the test current is more than 100 percent of the switching current of the rated filter bank.
As can be seen from the above description of the present invention, compared with the prior art, the method for measuring the maximum switching phase angle of the phase selection and switching-on device of the extra-high voltage converter station according to the present invention has at least one of the following beneficial effects:
1. the invention provides a brand-new method for measuring the maximum switching-on phase angle of an alternating current filter field phase selection switching-on device of an extra-high voltage converter station, which is different from the previous measuring method based on the operation experience of other converter stations, takes the actual parameters and the operation condition of the converter stations into consideration, and can more accurately measure the maximum switching-on phase angle of the phase selection switching-on device;
2. the method provided by the invention is based on test data, the reliability is higher, and the measurement result is more accurate;
3. the method provided by the invention is simulated based on the actual operation parameters of the converter station, not only the actual operation parameters of the converter station are considered, but also the efficiency of calculating the inrush current condition of the alternating current filter field is improved, and the method is more feasible and persuasive.
Drawings
FIG. 1 is a flowchart illustrating steps of a method for measuring a maximum switching-on phase angle of a phase selection switching-on device of an extra-high voltage converter station according to an embodiment of the present invention;
fig. 2 is a diagram of the electrical main connections of the converter station in a preferred embodiment of the invention.
Detailed Description
The technical solutions in the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments.
In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "connected" and "connected" are to be interpreted broadly, e.g., as being fixed or detachable or integrally connected; can be mechanically or electrically connected; may be directly connected or indirectly connected through an intermediate. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
Referring to fig. 1-2, in a preferred embodiment of the present invention, a method for measuring a maximum switching phase angle of a phase selection and switching device of an extra-high voltage converter station includes the following steps:
step 2, building a PSCAD simulation model according to the electric main wiring and actual parameters of the converter station;
step 3, carrying out simulation operation according to the PSCAD simulation model, and calculating the inrush current condition of the alternating current filter field under different closing phase angles;
and 4, obtaining the maximum switching-on phase angle of the phase selection switching-on device of the extra-high voltage converter station based on the inrush current condition and according to the maximum tolerant inrush current.
The invention provides a brand-new method for measuring the maximum switching-on phase angle of an alternating current filter field phase selection switching-on device of an extra-high voltage converter station, which is different from the previous measuring method based on the operation experience of other converter stations, takes the actual parameters and the operation condition of the converter stations into consideration, and can more accurately measure the maximum switching-on phase angle of the phase selection switching-on device; the method provided by the invention is based on test data, the reliability is higher, and the measurement result is more accurate; the method provided by the invention is simulated based on the actual operation parameters of the converter station, not only the actual operation parameters of the converter station are considered, but also the efficiency of calculating the inrush current condition of the alternating current filter field is improved, and the method is more feasible and persuasive.
As a preferred embodiment of the present invention, it may also have the following additional technical features:
in this embodiment, in step 1, the capacitive current test includes a basic test and a current open/close limit test, and the basic test is performed first, and then the current open/close limit test is performed.
In the embodiment, the basic test comprises a first test, the first test comprises 48 opening operation tests, the test conditions of the first test comprise that the operating voltage of the tripper adopts the highest voltage, the operating and breaking pressure adopts the lowest functional pressure, and the test current is 10-40 percent of the breaking current of the rated filter bank.
In this embodiment, the basic test includes a second test, where the second test includes performing 120 switching-on/switching-off operation tests, and the test conditions of the second test include that the operating voltage of the trip unit adopts the highest voltage, the operating and switching-off pressures adopt the rated voltages, and the test current is more than 100 percent of the switching-off current of the rated filter bank.
In this embodiment, the basic test includes a third test, the third test includes performing 12 times of opening operation tests, and the test conditions of the third test include that the operating voltage of the trip unit adopts the highest voltage, the operating and breaking pressures adopt the rated voltage, and the test current is more than 100 percent of the breaking current of the rated filter bank.
In this embodiment, the current switching limit test includes 60 switching operations in a first polarity, 48 switching operations in a first polarity and no-load state, 60 switching operations in a second polarity, and 48 switching operations in a second polarity and no-load state.
In this embodiment, the test conditions of the current open-close limit test include that the operating voltage of the trip unit adopts the highest voltage, the operating and open pressures adopt the rated voltage, and the test current is more than 100 percent of the open current of the rated filter bank.
To facilitate an understanding of the invention, a more specific embodiment is provided below:
the test mode of the capacitive current opening and closing test is shown in table 1, the first test, the second test and the third test are basic tests, O represents opening and C represents closing.
TABLE 1
The first test should include a total of 48O, the second test should include a total of 120 CO, the third test should include a total of 12O, and the current open/close limit test should include several cycles each with a total of 120C and 96 CO (C in unloaded condition).
The test frequency of the basic test mode is limited, in order to verify the limit of the filter bank current switching capacity and the heavy breakdown probability of the breaker, a user negotiates with a manufacturing plant, after the basic test, the filter bank current switching limit test is carried out on the same sample without any maintenance, the cycle is carried out in turn, the next round of test is carried out after each round of pass, 4 rounds of test are completed at most, and the operation cycle of each round of test is as follows:
test mode 4 (BCM)
-60C, distributed over the first polarity;
-48 CO (C in unloaded state), distributed over the first polarity;
-60C, distributed over the second polarity;
48 COs (C in the unloaded state) are distributed over the second polarity.
For the capacitive current test, the closing inrush current and the frequency are determined according to the optimized value (generally 20 kA/4 and 250 Hz) of the rated back-to-back filter bank closing inrush current, and can also be determined by negotiation between a manufacturer and a user according to the closing inrush current and the frequency calculated by a closing resistor or a phase selection controller.
The converter station generally has three filter banks, i.e. HP12/24, HP3 and SC, wherein HP12/24 and HP3 are filter banks for removing harmonic waves, and SC is a filter bank for reactive compensation.
Taking a certain converter station as an example, the electrical main wiring of the converter station is shown in fig. 2. And building a PSCAD simulation model according to the electrical main wiring diagram and the filter bank parameters.
According to the filter structure and parameters in practical application, the inrush current value of the SC filter bank is far greater than that of the HP12/24 and HP3 filter banks, so that only the inrush current generated by SC is considered. The detailed results of the maximum inrush current of the SC filter bank at different phase angles are shown in table 2.
TABLE 2
If the maximum tolerable inrush current obtained by the capacitive current test is 8KA, the maximum closing phase angle is 29 degrees according to the table 2.
The above additional technical features can be freely combined and used in superposition by those skilled in the art without conflict.
It is to be understood that the present invention has been described with reference to certain embodiments, and that various changes in the features and embodiments, or equivalent substitutions may be made therein by those skilled in the art without departing from the spirit and scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.
Claims (4)
1. A method for measuring the maximum switching phase angle of a phase selection switching-on device of an extra-high voltage converter station is characterized by comprising the following steps:
step 1, carrying out a capacitive current test on a circuit breaker of an alternating current filter field of a converter station to obtain the maximum withstand inrush current of the converter station;
step 2, building a PSCAD simulation model according to the electric main wiring and actual parameters of the converter station;
step 3, carrying out simulation operation according to the PSCAD simulation model, and calculating the inrush current condition of the alternating current filter field under different closing phase angles;
and 4, obtaining the maximum switching-on phase angle of the phase selection switching-on device of the extra-high voltage converter station based on the inrush current condition and according to the maximum tolerant inrush current.
2. The method for measuring the maximum switching-on phase angle of the phase selection and switching-on device of the extra-high voltage converter station according to claim 1 is characterized in that: in step 1, the capacitive current test includes a basic test and a current switching limit test, the basic test is performed first, and then the current switching limit test is performed, specifically, the basic test includes:
the first test comprises 48 times of opening operation tests, and the test conditions of the first test comprise that the operating voltage of the tripper adopts the highest voltage, the operating and breaking pressures adopt the lowest functional pressure, and the test current is 10-40 percent of the breaking current of a rated filter bank;
the second test comprises a 120-time switching-on and switching-off operation test, wherein the test conditions of the second test comprise that the operating voltage of the tripper adopts the highest voltage, the operating and switching-off pressures adopt rated pressures, and the test current is more than 100 percent of the switching-off current of a rated filter bank;
and a third test, wherein the third test comprises 12 times of opening operation tests, and the test conditions of the third test comprise that the operating voltage of the tripper adopts the highest voltage, the operating and breaking pressures adopt rated pressures, and the test current is more than 100 percent of the breaking current of the rated filter bank.
3. The method for measuring the maximum switching-on phase angle of the phase selection and switching-on device of the extra-high voltage converter station according to claim 2 is characterized in that: the current switching limit test comprises 60 switching-on operation tests on a first polarity, 48 switching-on and switching-off operation tests on the first polarity and switching-on operation under an unloaded state, 60 switching-on operation tests on a second polarity, and 48 switching-on and switching-off operation tests on the second polarity and switching-on operation under an unloaded state.
4. The method for measuring the maximum switching-on phase angle of the phase selection and switching-on device of the extra-high voltage converter station according to claim 3 is characterized in that: the test conditions of the current switching limit test comprise that the operating voltage of the tripper adopts the highest voltage, the operating and switching pressures adopt the rated voltage, and the test current is more than 100 percent of the switching current of the rated filter bank.
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