An auto-disturbance rejection control scheme for hybrid power compensators

In application of power electronics devices, one of the major concerns is related to correcting power factors and eliminating the harmonic currents in network-side. In this paper an auto-disturbance rejection control (ADRC) scheme for hybrid power compensators (HPC) is presented, which has the function to correct power factor and eliminate harmonics effectively. The original is firstly changed into a tracing problem, where the reference input is a sinusoidal signal with given phase. Then disturbances can be estimated by extended state observer (ESO) and compensated. And a nonlinear state-error-feedback (NLSEF) is employed to realize the tracing of reference input. A distinguished feature of the control strategy is that it needs not to detect harmonics accurately. Hybrid power compensators built on the basis of this control scheme have strong adaptability for different typical loads and the variations in magnitude and phase of load-side currents. Test results prove the effectiveness of the control scheme.