Novel Control Method for a Hybrid Active Power Filter with Injection Circuit Using a Hybrid Fuzzy Controller

Abstract

This paper analyses the mathematical model and control strategies of a Hybrid Active Power Filter with Injection Circuit (IHAPF). The control strategy based on the load harmonic current detection is selected. A novel control method for a IHAPF, which is based on the analyzed control mathematical model, is proposed. It consists of two closed-control loops. The upper closed-control loop consists of a single fuzzy logic controller and the IHAPF model, while the lower closed-control loop is composed of an Adaptive Network based Fuzzy Inference System (ANFIS) controller, a Neural Generalized Predictive (NGP) regulator and the IHAPF model. The purpose of the lower closed-control loop is to improve the performance of the upper closedcontrol loop. When compared to other control methods, the simulation and experimental results show that the proposed control method has the advantages of a shorter response time, good online control and very effective harmonics reduction.

Improved p-q Harmonic Detection Method for Hybrid Active Power Filter

“…When the improved p-q method is used, the transient time is almost zero and 0.01s (0.2s ÷ 0.21s), the overshoot is almost zero when the load before and after change, total harmonic distortion of the supply current in steady-state is 1.21% (0.1s ÷ 0.2s) and 1.42% (0.3s ÷ 0.4s). In addition, the supply current of the proposed method is also compared to methods in [5], [6], [12], [13], [16] as summarized in Table 4, mainly compared in the transient duration. In summary, the simulation results demonstrate that the improved p-q harmonic detection method has cancelled the disadvantages of the traditional p-q harmonic detection method, which aims to reduce the transient time, reduce the overshoot.…”

“…Table 4. Comparison of Supply Current between the Proposed Method and the Methods in [5], [6], [12], [13], [16] Transient time (s) Overshoot (%) low-pass filter method [5] 0.05 23.59 High-pass filter method [6] 0.05 22.9 Neural method [12] 0.02 25.7 Active and reactive power method [13] 0.04 0,00 Improved FBD method [16] 0.025 0.00 Proposed method 0.01 0.00…”

“…There are many harmonic detection methods have been proposed for HAPF. Traditional harmonic detection methods include: the low-pass filter (LPF) [4], [5], high-pass filter (HPF) [6], fast Fourier transform [7] and p-q instantaneous power theory [8], [9]. The low-pass and high-pass filters have slow response and only a slight variation of frequency will also result in a significant phase shifting.…”

Cost-Effective APF/UPS System with Seamless Mode Transfer

“…To extract the load current harmonics from the synchronous d e -q e reference, implementation of a highpass filter is realized as (1-LPF). Implementation of the low-pass filter used in the controller is realized with a cutoff frequency of 20 Hz [16]. Detection of the source voltage also requires the use of a d-q transformation with an all-pass filter.…”

Versatile Shunt Hybrid Power Filter to Simultaneously Compensate Harmonic Currents and Reactive Power

“…Unfortunately, due to the series connection of passive and active parts, this type of SHPF can supply only a fixed amount of reactive power; it is unable to perform a dynamic reactive power compensation function when the load changes. To overcome this limitation, several novel SHPF topologies have been proposed to simultaneously take into account the harmonic currents and the reactive power [10][11][12][13][14]. In [10][11][12], additional passive components, such as capacitors, inductors, or coupling transformers, were inserted into the typical SHPF to improve harmonic current and reactive power compensation capability.…”