REACTION POWER COMPENSATOR Russian patent published in 1994 - IPC

FIELD: electrical engineering. SUBSTANCE: compensator can be used at A C substation for control over reactive power. Single-phase bridges built on two thyristors and two diode valves placed into opposite arms of bridge are connected in each phase between supply buses and three-phase input of both bridges. Current limiting reactor providing for limitation of emergency currents and voltages is put into D C arm of bridge. Optimization of control over thyristors is achieved due to setting of regulation angles for each bridge of compensator. In this case under condition of consumption of reactive power regulation angle of first bridge is close to 75 el. deg and of second bridge - to (105-δ) el. deg. and with generation of reactive power they are close to 75 el. deg. and (105-δ) el. deg. correspondingly, where δ is equal to 2 arctg ( p/IQI), where p is loss of active power in compensator and Q is absolute value of reactive power consumed or generated by compensator. Thanks to such approach reduction of cost of thyristor groups of key bridges is achieved as flow of emergency currents through them and effects of high overvoltages are avoided. Operation of compensator is optimized due to improvement of law of control over thyristors. EFFECT: reduced cost and enhanced reliability of compensator by way of limiting of emergency currents and overvoltages and optimization of switching angles of first and second bridges. 1 dwg, 1 tbl