Method and System for AC Line Distance Protection in AC/DC Hybrid Power Grid, and Storage Medium

A system for AC line distance protection in AC/DC hybrid power grid, comprising:

• a data collection device, a first processor for current calculation, a second processor for virtual fault location calculation and a third processor for protection control,
• the data collection device configured to collect operation parameters of inverter-side converter, AC parameters, converter bus voltage, current of a distance protection installation and operation parameters of smoothing reactor of inverter station;
• the first processor for current calculation configured to determine a conduction state of the inverter-side converter, according to the operation parameters of the inverter-side converter;
• and configured to determine current fed into the AC system from the DC system corresponding to the conduction state, according to the operation parameters of the inverter-side converter, the operation parameters of the smoothing reactor of the inverter station and the converter bus voltage;
• the second processor for virtual fault location calculation configured to determine a virtual fault location and a virtual transition resistance, according to a fault type, the current fed into the AC system from the DC system and the AC parameters;
• the third processor for protection control configured to control a corresponding protection device to perform protection action, according to the current at distance protection installation the virtual fault location and the virtual transition resistance.

A non-transitory machine-readable storage medium comprising instructions that when executed cause a processor of a computing device to:

• collecting operation parameters of inverter-side converter, AC parameters, converter bus voltage, current of distance protection installation and operation parameters of smoothing reactor of inverter station;
• determining conduction state of the inverter-side converter according to the operation parameters of the inverter-side converter;
• determining current fed into the AC system from the DC system corresponding to the conduction state according to the operation parameters of the inverter-side converter, the operation parameters of the smoothing reactor of the inverter station and the converter bus voltage;
• determining a virtual fault location and a virtual transition resistance according to a fault type, the current fed into the AC system from the DC system and the AC parameters;
• controlling a corresponding protection device to perform protection action according to the current at the distance protection installation, the virtual fault location and the virtual transition resistance.