Switching selection control method and system for filter of open-loop and closed-loop alternating-current system

Abstract

The invention relates to a switching selection control method and a switching selection control system for filters of a split-closed loop alternating current system. Priority initial values of switching-in and switching-off sequences are set for each group of filters; when a group of filters need to be selected for input, the filter with the highest input priority in the filters in the input state is selected for input, the cut-off priority of the input filter is set to be the lowest, and the cut-off priorities of other filters are improved by one level; when a group of filters need to be selected to be cut off, the filter with the highest cut-off priority in the filters in the cut-off state is selected to be put into use, the put-in priority of the put-in filter is set to be the lowest, and the put-in priorities of other filters are improved by one level. According to the method, the phenomenon of multi-switching or multi-switching of a filter field in a short time when an alternating current field bus tie circuit breaker trips off and is switched from closed-loop operation to open-loop operation is avoided, the situation that a certain alternating current filter is unavailable and the filter cannot be switched on or switched off due to reactive power control in a closed-loop operation mode is avoided, and normal operation of a direct current system is ensured.

Description

Technical field [0001] The invention relates to the technical field of high-voltage DC converter stations, and in particular to a filter switching selection control method and system for a split-loop AC system. Background technique [0002] The split-loop and closed-loop operation modes of the AC system of the high-voltage DC converter station can be realized through the opening and closing status of the bus tie breaker in the AC field. The corresponding filter field can also realize unified control of all filters or divide it into two filters based on the status of the bus tie breaker. The device field is controlled independently. Due to some abnormal reasons, the AC system and the filter field may be passively switched from closed-loop operation to split-loop operation due to the abnormal tripping of the bus coupler switch. If the reactive power control function is selected during the closed loop, the next sub-filter switching is selected. The design of the control method...

AI Technical Summary

Problems solved by technology

Due to some abnormal reasons, the AC system and the filter field may switch from closed-loop operation to split-loop operation mode passively due to abnormal bus-tie switch tripping, and if the loop is closed, the reactive power control function will switch to the next sub-filter to select The design of the control method is unreasonable, which leads to the unbalanced number of filters in the two filter fields after the split-loop operation. In the same period of time, a filter field in the AC system will continuously cut off multiple groups of filters due to excess reactive power. Another filter site is located in the AC system, because the harmonic performance or reactive power output does not meet the system requirements, multiple sets of filters are continuously used, which affects the stable operation of the system

[0003] At present, how to realize the balance of filter types and numbers in the two filter fields in the transition from ring closing to ring splitting based on the fact that the switching probability of each filter is equal to the current domestic HVDC converter station. Issue still in research discussion stage

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