Title :
Decreasing the commutation failure frequency in HVDC transmission systems
Author :
Hansen, Arne ; Havemann, Henrik
Author_Institution :
Dept. of Electr. Power Eng., Tech. Univ. Denmark, Lyngby, Denmark
fDate :
7/1/2000 12:00:00 AM
Abstract :
In this paper we show how a fairly large proportion of those commutation failures that are due to single-phased short circuits to earth can be avoided. In a control circuit based on a digital signal processor (DSP) it is possible, with instantaneous results, to switch from a normal control strategy with equidistant firing pulses to a strategy that takes into consideration the potentially dangerous voltage changes on the supply lines, If the supply voltages are monitored continuously, it is possible to calculate the necessity of advancing the firing pulses to avoid commutation failures. In the paper such a calculation technique is described. The monitoring times may be approximately 50 μsec apart corresponding to a distance of 0.016 radians or about 1
Keywords :
HVDC power transmission; commutation; digital control; digital signal processing chips; monitoring; power system faults; power transmission control; short-circuit currents; switching; voltage measurement; DSP; HVDC transmission systems; commutation failure frequency decrease; commutation failures avoidance; control circuit; digital control; digital signal processor; equidistant firing pulses; normal control strategy; potentially dangerous voltage changes; single-phased short circuits; supply lines voltage changes; supply voltages monitoring; Condition monitoring; Digital signal processing; Digital signal processors; Earth; Frequency; HVDC transmission; Pulse circuits; Switches; Switching circuits; Voltage control;
Journal_Title :
Power Delivery, IEEE Transactions on