A Novel Control for Load Voltage Conditioning by a Series Power Quality Controller without DC Energy Source

The ride through capability is quite crucial for Series Power Quality Controllers (SPQC). While both the in-phase control and the energy optimized control for SPQC can’t provide very long ride through time as the system power loss. In this paper, a novel control strategy for SPQC without DC energy source is proposed, which increases the ride through capability by absorbing some active power to compensate the system power loss in the time of source voltage disturbance compensation, and a detailed analysis on this improved control strategy is presented accordingly. Firstly a specific phasor diagram representation of SPQC is introduced, which uses load current phasor as reference phasor and leads simple relationship for related variables, and the phasor diagram analysis is done accordingly, for in the time of both source voltage disturbances and normal state. Then the compensating voltage magnitude of SPQC using this novel control strategy is obtained quantitatively in both the voltage disturbances and normal state, and the quantitative maximal compensable range is discussed also. Subsequently, a unified implementation method for this novel control is proposed and analyzed extensively. In the end, the computer simulation and the prototype experimental results are shown to verify the validity of all the analysis of control.