Three phase inverter control using DSP controller for dynamic voltage restorer (DVR) application

This paper discusses the control technique improvement of a three-phase inverter using directquadrature- zero (d-q-0) controller based on DSP TMS320F2812 for dynamic voltage restorer (DVR) applications. The output of the inverter is then connected to a voltage grid via a second order filter and injection transformer. The control algorithms are developed using TMS320F 2812 DSP. The proposed technique achieves voltage regulation with low total harmonics distortion (THD) for both voltage and current. This paper also highlights a series of discussion, analysis and studies performed on the proposed control technique, including L-C filter design issue and the concept of DVR in the distribution system. An analysis and experimental results validate the effectiveness of the DSP controller in mitigating voltage sags and harmonics issues in the distribution syste

Voltage Swells Improvement in Low Voltage Network Using Dynamic Voltage Restorer

Abstract: Problem statement: Voltage disturbances are the most common power quality problem due to the increased use of a large numbers of sophisticated electronic equipment in industrial distribution system. The voltage disturbances such as voltage sags, swells, harmonics, unbalance and flickers. High quality in the power supply is needed, since failures due to such disturbances usually have a high impact on production cost. There are many different solutions to compensate voltage disturbances but the use of a DVR is considered to be the most cost effective method. The objective of this study is to propose a new topology of a DVR in order to mitigate voltage swells using a powerful power custom device namely the Dynamic Voltage Restorer (DVR). Approach: New configuration of a DVR with an improvement of a controller based on direct-quadrature-zero method has been introduced to compensate voltage swells in the network. Results: The effectiveness of the DVR with its controller were verify using Matlab/Simulink’s SimPower Toolbox and then implemented using 5KVA DVR experimental setup. Simulations and experimental results demonstrate the effective dynamic performance of the proposed configuration. Conclusion: The implimentation of the proposed DVR validate the capabilities in mitigating of voltage swells effectiveness.During voltage swells, the DVR injects an appropriate voltage to maintain the load voltage at its nominal value

DSP-based flexible digital hysteresis in switched capacitor active power filter

This paper proposes implementation of digital signal processor (DSP) to perform flexible-band digital hysteresis current control in a switched capacitor active power filter (SCAPF). By integrating hysteresis current control with digital-based neural network harmonic detection, the proposed SCAPF forces the supply current to be sinusoidal, to have low current harmonics, and to be in phase with the line voltage. Simulation on MATLAB Simulink verified the controller's algorithm design, and a purpose-built laboratory SCAPF system tested its feasibility

Experimental investigation of on-site degradation of crystalline silicon PV modules under Malaysian climatic condition

Photovoltaic (PV) power plant capacity is growing very fast in Malaysia. The operating capacity of a PV plant digresses from the installed capacity after several years of operation. The degradation rate of different poly and mono crystalline silicon PV modules due to real field aging at various time spans has been detected by EL imaging, maximum power measurement and dark I-V analysis. The obtained degradation values of PV modules are 1.78, 7.06, 13.92, 17.04 and 17.42% due to ageing at a period of 8 months, 16 months, 4 years, 9 years and 11 years, respectively. The reason behind this degradation is attributed to the reduction of shunt resistance which declines gradually as result of aging. The degradation rate of a PV module has been estimated as 18.61% after 21 years of aging. Temperature coefficient of maximum power of PV module also degrades due to aging. And the rate of temperature coefficient of maximum power degradation decreases with the increase of aging period

New Topology of a Three Phase Dynamic Voltage Restorer (DVR) for Voltage Swells Mitigation in Electrical Distribution System

This paper proposed three topologies of a three phase dynamic voltage restorer (DVR), these new topologies comprises of filtering schemes, dc-link capacitor and three phase four wire of a three phase transformer connection. The new Topology of the DVR based on direct- quadrature –zero (d-q-0) transformation technique controller is presented .The proposed topologies of a DVR can compensate three phase voltage swells outages. MATLAB/SIMULINK power system toolbox is used to simulate the proposed system. To validate the effectiveness of the control proposed a three phase DVR prototype with a power rating of 5KVA has been successfully developed. Simulation and experimental results verify the capabilities of the proposed topologies in mitigating voltage swells in the distribution network. Keywords: filtering scheme, prototype, dynamic voltage restorer, voltage swells, three phase voltage. swells in the distribution network

Impact of fill factor on input current ripple of photovoltaic system

This paper discusses the impact of fill factor on the input current ripple of the photovoltaic module and the loss effect on power extracted. Photovoltaic module's P-V curve produces exponential curve. The curvature of this curve indicates the fill factor of the particular cell; hence, by increasing the fill factor, the available extracted power increases. Yet, this paper states that losses due to photovoltaic current increases by increasing the fill factor

Fuzzy Logic Control Approach of a Maximum Power Point Employing SEPIC Converter for Standalone Photovoltaic System

AbstractThis paper presents a new fuzzy logic controller as a maximum power point tracker employing single-ended primary-inductor (SEPIC) converter. The new controller improves perturb and observe search method with rules to fuzzify and eliminate its drawbacks. An accurate and fast converging to maximum power point is offered by fuzzy logic tracker during both steady-state and varying weather conditions compared to conventional maximum power point tracking methods. The performance of the proposed maximum power point tracker is demonstrated in both simulation and experiment at different operating conditions

Modeling and simulation of new configuration of dynamic voltage restorer for power quality improvement

The dynamic voltage restorer (DVR) is a custom device that is used to maintain the voltage at the load terminals from various power quality problems from a disurbed incoming supply. In this paper, a novel control strategy is described for mitigation of voltage sags and swells on sensitive loads. The new control of the compensation voltages in the DVR based on the dq0 algorithm is discussed. The MATLAB/SIMULINK SimPower System toolbox has been used to obtain simulation results in order to verify the proposed scheme. From the results, it shows that the DVR is able to compensate the voltage sag or swell at sensitive loads by injecting an appropriate voltage through the injection transformer

Multi-Stage Fast Charging Technique for Lithium Battery in Photovoltaic systems

In renewable energy resources such as photovoltaic (PV) systems, fast charging is an emerging case for the battery charger. In this paper, constant-current (CC) and constant-voltage (CV) charging scheme has been studied since it has the highest possible reliability for lithium based batteries. In this work a new charging technique to expedite charging time is proposed. This is a multi-stage technique which improves the threshold voltage detection during CC-stage. Thus the transition to CV-stage occurs accurately at the knee voltage. The novelty of the proposed technique is in the charging algorithm. An experiment was setup based on PIC18f4520 microcontroller. The performance of the proposed technique and the conventional CC-CV Li-ion battery charger has been compared. The result of the proposed technique shows that there is 20% improvement in charging time compared to the conventional CC-CV Li-ion battery charger. © 2022 IEEE

Three-phase switched capacitor active power filter with modified artificial neural network and flexible-band hysteresis.

This paper presents design and development of a three-phase switched capacitor active power filter (APF) to reduce line-current harmonics and operate in-phase with line voltage. Its control design combines a modified artificial neural network (ANN) harmonic detection technique and flexible-band hysteresis current control. The modified ANN with a suitable learning rate produces good and fast harmonic reference current for use in the switching algorithm, which performs flexible-band through embedded with band and without band hysteresis current control. MATLAB Simulink software verified the proposed APF's topology and controller. A laboratory-built three-phase switched capacitor APF tested its feasibility. Simulation and experimental results verified its performance. It compensated harmonic current well, and the source current waveform became almost sinusoidal with near unity power factor. The results show that the three-phase switched capacitor APF with the modified ANN and the digital flexible-band hysteresis current algorithms could reduce THD and could increase power factor of the system