Virtual voltage source control for 2×27 MVA machine test bench

摘要

In this paper, a special control solution called “Virtual Voltage Source” is developed for no-load tests of induction machines. This concept is applied to a 2×27 MVA high-power machine test bench, where the test bench is requested to precisely characterize e.g. 3 MW machines at no-load currents. The developed Virtual Voltage Source thoroughly solves the stability issue of induction machines at low speed ranges. A set of optimizations is presented here that systematically improves the voltage precision of the test bench. Experimental results prove that the proposed concept achieves 0.08-0.12% voltage unbalance, less than 1% current unbalance, with less than 0.3% Harmonic-Voltage-Factor, verified by more than 100 induction machines.