Non-ideal Mains Voltage Conditions Research Articles

Neural network-based shunt active filter with direct current control for power quality conditioning

In this paper, a novel phase locked loop less control algorithm for harmonic and reactive power compensation with power factor improvement using three-phase shunt active power filter under non-ideal mains voltage conditions is presented. The performance of APF mainly depends upon how quickly and accurately compensation signal are estimated. The artificial neural network trained with conventional compensator data, can deliver compensation signals more accurately at varied load condition. The non-sinusoidal mains voltage problem is resolved by using neural network-based control system which estimates the reference compensation currents by extracting fundamental frequency components. The compensation process is based on sensing source currents only, without sensing source voltage and load currents, which gives more simplicity in control with less number of sensors. The proposed compensation approach has been first evaluated in MATLAB/Simulink. The simulated results are validated experimentally by developing a laboratory prototype using a floating-point DSP TMS320F28335 to show the effectiveness of the controller.

Control of a 3-phase 4-leg active power filter under non-ideal mains voltage condition

In this paper, instantaneous reactive power theory (IRP), also known as p– q theory based a new control algorithm is proposed for 3-phase 4-wire and 4-leg shunt active power filter (APF) to suppress harmonic currents, compensate reactive power and neutral line current and balance the load currents under unbalanced non-linear load and non-ideal mains voltage conditions. The APF is composed from 4-leg voltage source inverter (VSI) with a common DC-link capacitor and hysteresis–band PWM current controller. In order to show validity of the proposed control algorithm, compared conventional p– q and p– q– r theory, four different cases such as ideal and unbalanced and balanced-distorted and unbalanced-distorted mains voltage conditions are considered and then simulated. All simulations are performed by using Matlab-Simulink Power System Blockset. The performance of the 4-leg APF with the proposed control algorithm is found considerably effective and adequate to compensate harmonics, reactive power and neutral current and balance load currents under all non-ideal mains voltage scenarios.

Harmonic and reactive power compensation with shunt active power filter under non-ideal mains voltage

This paper presents a new control algorithm for an active power filter (APF) to compensate harmonic and reactive power of a 3-phase thyristor bridge rectifier under non-ideal mains voltage scenarios. Sensing load current, dc bus voltage and source voltages compute reference currents of the APF. APF driving signals are produced with these signals via a hysteresis band current controller. Matlab/simulink power system toolbox is used to simulate the proposed system. The proposed method's performance is compared with conventional instantaneous power ( p– q) theory. The simulation results are presented and discussed showing the effectiveness of the control algorithm. The proposed algorithm is found quite satisfactory to compensate the reactive power and harmonics under non-ideal mains voltage conditions. The increased performance of the active power filter under different non-sinusoidal mains voltage and dynamic load conditions are extensively demonstrated.