Control strategy is researched for cascaded medium high static synchronous compensator to provide synthetic compensation ability of reactive power, harmonics and asymmetric currents.Basing on selective harmonic compensation strategy, a reference current detection method utilizing the combination of synchronous reference frame transformation and discrete Fourier transformation is proposed.The tracking control Salad Spinner of instruction current is implemented by multi-copyright pulse width modulation (PWM).In allusion to the multi-copyright PWM, the capacitor voltage balancing control at the dc side is Cable Tidy Solutions realized by a type of software based on the energy balance principle of the inverter bridge.
The proposed control strategy is convenient for engineering implementation given its low calculation burden and simplicity.The effectiveness of the proposed control strategy is proven by both simulation and experimental results.