Analytical Study of the Series Resonance in Power Systems With the Steinmetz Circuit

In traction systems, it is usual to connect reactances in delta configuration with single-phase loads to reduce voltage unbalances. This set is called a Steinmetz circuit. Parallel and series resonances can occur between the Steinmetz capacitor and system inductors, increasing harmonic voltage distortion. It is important to analyze the series resonance ldquoobservedrdquo from the supply system to avoid harmonic problems due to background voltage distortion. The paper studies this resonance analytically and presents simple expressions to locate it. Experimental measurements are also provided to validate the obtained analytical results.