Laboratory research on the series-type solid-state variable capacitive reactance compensators based on (1) the voltage-source converter topology and (2) the current-source converter topology is reported. The two topologies are circuit duals of each other and are studied together to evaluate their relative merits. The capacitive reactance compensators are based on GTOs, which have both gate-turn-on and gate-turn-off capabilities, operated under pulse width modulation (PWM). The practicality of the concepts is demonstrated by 1 kVA size bipolar transistors converters as laboratory models of the GTO stations. After experimental demonstration, the research is followed by digital simulations. >