Development of Fault Current Limiters for Electric Power Systems.

摘要

In the report,current commutation to a parallel resistor is shown to be a feasible fault current limiter concept in general,and specifically a conceptual limiter using a sand fuse as the arc voltage source or commutation device and a linear ohmic resistor as the parallel resistance is developed for at least to a 72.5kV system voltage. A simple current rate of rise (di/dt) sensing criteria with appropriate time delay (delta t) to filter out noise etc. is employed as the fault sensor. Finally, a bypass switch is developed to carry the continuous load current,and fuse selector and fuse insertion switches introduce a new current commutating fuse after each operation of the fault current limiter. An LC resonant fault current limiter is shown to be economically attractive at system voltages of 242kV and above. Voltage sensing is determined to be the best means of fault detection for the resonant limiter. Various capacitor and inductor designs are analyzed and presented,and other fault current limiter concepts including a cryogenic/superconducting type are also discussed.