Fault diagnosis method for three-phase power grid, apparatus, and computer device
In the fault diagnosis method, apparatus, and computer device, the method includes acquiring line voltage values in real time according to a voltage collector connected to phase lines (S 100 ); according to the line voltage values and preset system parameters, obtaining a voltage peak balance degree and a phase angle offset of the three-phase power grid (S 200 ); and obtaining a fault diagnosis result according to the voltage peak balance degree and the phase angle offset (S 300 ). In such a way, a real-time diagnosis operation of whether a three-phase power grid is balanced can be implemented only by performing on-line calculation and analysis on line voltage values, which has simple analysis operation to reduce the system complexity; and only a voltage collector is added, and no other hardware costs are required, moreover high diagnosis reliability is obtained.
1. A fault diagnosis method for a three-phase power grid, comprising:
acquiring line voltage values of the three-phase power grid, wherein the line voltage values are collected and sent in real time by a voltage collector connected to a phase line of the three-phase power grid;
obtaining a voltage peak balance degree and a phase angle offset of the three-phase power grid based on the line voltage values and a preset system parameter; and
obtaining a fault diagnosis result based on the voltage peak balance degree and the phase angle offset;
wherein said obtaining a voltage peak balance degree and a phase angle offset of the three-phase power grid based on the line voltage values and a preset system parameter comprises:
performing filtering analysis based on the line voltage values and the preset system parameter to obtain a filtered output line voltage value; and
obtaining a voltage peak balance degree and a phase angle offset of the three-phase power grid based on the filtered output line voltage value.
2. The fault diagnosis method as claimed in claim 1 , wherein the line voltage values comprise at least two of a first-phase line voltage value corresponding to a first phase, a second-phase line voltage value corresponding to a second phase, and a third-phase line voltage value corresponding to a third phase in the three-phase power grid.
3. The fault diagnosis method as claimed in claim 1 , wherein said obtaining a voltage peak balance degree and a phase angle offset of the three-phase power grid based on the filtered output line voltage value comprises:
obtaining a voltage peak value; and a phase voltage value, a phase angle value and a phase voltage peak value of a phase corresponding to the filtered output line voltage value, based on the filtered output line voltage value;
obtaining a voltage peak balance degree based on the voltage peak value and the phase voltage peak value; and
obtaining a phase angle offset based on the phase voltage value, the phase voltage peak value and the phase angle value.
4. The fault diagnosis method as claimed in claim 3 , wherein the line voltage values comprise a first-phase line voltage value and a second-phase line voltage value, and said performing filtering analysis based on the line voltage value and the preset system parameter to obtain a filtered output line voltage value comprises:
performing filter analysis based on the first-phase line voltage value and the preset system parameter to obtain a first-phase filtered output line voltage value; and
performing filter analysis based on the second-phase line voltage value and the preset system parameter to obtain a second-phase filtered output line voltage value.
5. The fault diagnosis method as claimed in claim 4 , wherein said obtaining a voltage peak value; and a phase voltage value, a phase angle value and a phase voltage peak value of a phase corresponding to the filtered output line voltage value, based on the filtered output line voltage value comprises:
obtaining a phase angle value of a phase corresponding to the first-phase filtered output line voltage value based on the first-phase filtered output line voltage value;
performing derivation to the first-phase filtered output line voltage value to obtain a processed first-phase filtered output line voltage value after derivation;
obtaining a phase voltage peak value of a phase corresponding to the first-phase filtered output line voltage value, and a voltage peak value, based on the first-phase filtered output line voltage value and the processed first-phase filtered output line voltage value; and
obtaining a phase voltage value of a phase corresponding to the first-phase filtered output line voltage value based on the voltage peak value and the second-phase filtered output line voltage value.
6. The fault diagnosis method as claimed in claim 1 , wherein said obtaining a fault diagnosis result based on the voltage peak balance degree and the phase angle offset comprises:
producing a detection result indicating an unbalanced three-phase power grid, once the voltage peak balance degree is not equal to 1 or the phase angle offset is not equal to 0; and
producing a detection result indicating a balanced three-phase power grid, once the voltage peak balance degree is equal to 1 and the phase angle offset is equal to 0.
7. A fault diagnosis apparatus for a three-phase power grid, comprising:
a voltage acquisition module, configured to acquire line voltage values of the three-phase power grid, wherein the line voltage values are collected and sent in real time by a voltage collector connected to a phase line of the three-phase power grid;
a parameter analysis module, configured to obtain a voltage peak balance degree and a phase angle offset of the three-phase power grid based on the line voltage values and a preset system parameter; and
a fault analysis module, configured to obtain a fault diagnosis result based on the voltage peak balance degree and the phase angle offset.
8. A computer device, comprising a memory and a processor, the memory being stored with computer programs, the processor being configured to execute the computer programs to implement steps of the method according to claim 1 .