Harmonic Current Detection Method Using Nonlinear Load's DC Output Voltage and Current

Single-phase Shunt Active Power Filter by Using Piecewise Linear Look-up Table Controller

“…Normally, a proportional plus integral (PI) controller is implemented as the compensator for APF [6]- [7]. The PI controller is a simple first order system which offers quite fast response with zero steady state error.…”

“…This technique has been implemented in APF, that proved its capability in compensating reactive power and successfully mitigating current harmonic distortion [2]. The first objective of this paper is to apply the harmonic detection method proposed in [7] and using PL-LTC as the compensator of SAPF. In addition, its performance is evaluated based on the achievement of a total harmonic distortion (THD) index of source current and the improvement of system power factor.…”

“…As depicted in Figure 2, the compensator is drived by the error e which is the difference between reference compensated current and actual compensated current. Using the technique introduced in [7], the reference compensated current is generated. The system to be compensated is a first order system which represents a filter inductor and an equivalent series resistance (ESR).…”

“…And the source voltage is given as: In order to mitigate harmonic component in the source current and improve the system power factor, the DCC method shows in Figure 5 is chosen as the preferred current control method. Usually the load current which have fundamental and harmonic components is filtered according to control strategy proposed in [7] and depicted in Figure 6. Instead of applying the AC load current and source voltage, the DC load current and voltage are selected as the input of the control strategy.…”

“…The DCC method is widely chosen for SAPF application because of many reasons, however the ICC method has an advantage of simpler control structure and requires only three sensors at least [6]. By selecting the DC load voltage and current as inputs, the nonlinear load equivalent resistance control strategy is applied as the control strategy to mitigate current harmonic and compensate reactive power [7].…”