ACTIVE AND REACTIVE POWER CONTROL OF GRID CONNECTED PHOTOVOLTAIC SYSTEM (original) (raw)

Direct control of active and reactive power for a grid-connected single-phase photovoltaic inverter

International Journal of Power Electronics and Drive Systems (IJPEDS), 2021

This paper presents a single-phase grid-connected photovoltaic system with direct control of active and reactive power through a power management system of a Photovoltaic inverter. The proposed control algorithm is designed to allow maximum utilization of the inverter’s available KVA capacity while maintaining grid power factor and current total harmonic distortion (THD) requirements within the grid standards. To reduce the complexity and improve the efficiency of the system, two independent PI controllers are implemented to control single-phase unipolar PWM voltage source inverter. One controller is used to control the power angle, and hence the active power flow, while the other controller is used to control the reactive power, and consequently the power factor by adjusting thevoltage modulation index of the inverter. The proposed system is modelled and simulated using MATLAB/Simulink. The PV inverter has been examined while being simultaneously connected to grid and local load. Results obtained showed the ability of the PV inverter to manage the active and reactive power flow at, and below rated levels of solar irradiances; resulting in an increased inverter utilization factor, and enhanced power quality. The proposed system, was capable of operating at power factors in the range of 0.9 lead or lag for reactive power compensation purposes and delivered its power at a wide range of solar irradiance variations.

Active and reactive power control of three phase grid connected PV system

International Journal of Smart Grid and Green Communications, 2018

This paper deals with active and reactive power control of a three phase grid connected photovoltaic system. Maximum power point tracking (MPPT) algorithm is used to track the MPP. The MPPT algorithm uses the I PV and V PV of the PV array and gives the MPP and a V dc,ref. This voltage is then passed on to the inverter and then further to the three-phase grid. The behaviour of the active and reactive power of the grid which is supplied by the PV array is investigated. The various currents such as inverter current, grid current and load currents are also investigated. MATLAB/simulink has been used to carry out the simulations. The proposed work has also been experimentally verified.

Active Power Control in Grid Connected Photovoltaic System

This paper proposes a design of grid connected photo-voltaic (PV) system through implementation of active power control & MPPT control using MATLAB/Simulink. In the present scenario of world energy sector renewable sources are growing their importance day by day. The overall system model consists of a PV array, MPPT controller, Inverter and a distribution system to deliver usable power to the end grid. However, the output of solar arrays varies due to change of solar irradiation and weather conditions. Therefore, the maximum power point tracking algorithm is implemented in DC/DC converter to enable PV arrays to operate at maximum power point. The Perturb & Observe (P&O) algorithm is employed to control the boost converter. Then the central inverter is controlled by using the PI controller for active power control, which is necessary to ensure that all maximum power is transferred to the grid. Active power control is cost effective & it improves the efficiency of the system. After the complete designing of the grid connected photovoltaic system, we analysed the performance results of the PV system in MATLAB. Keywords: active power control, grid connected photovoltaic system, maximum power point tracking (MPPT), PI control, voltage source inverter ________________________________________________________________________________________________________

Operation Methods for Grid-Connected PV System for Voltage Control in Distribution System – a Review

ASIAN JOURNAL OF CONVERGENCE IN TECHNOLOGY, 2019

PV solar systems employ inverters to transform dc power from solar panels into ac power for injecting into the power grids. Inverters that perform multiple functions in addition to real power production are known as "smart inverters". This paper presents a novel control of PV inverter as a dynamic reactive power compensator-STATCOM. This "smart PV inverter" control enables a PV solar inverter to operate in three modes-i) Full PV, ii) Partial STATCOM, and iii) Full STATCOM, depending upon system needs.

Research of the Reactive Power Control Possibilities in the Grid-tied PV Power Plant

Electronics and Electrical Engineering, 2013

Results of control possibilities research of the reactive power generated by grid-tied PV power plant are presented in this paper. The innovative grid-connected inverter with the intermediate power storage chain (DC/DC converter) is used for the PV power plant. The converter operates well when DC input voltage generated by the PV source changes in a wide range. Mathematical description for the circuit part between the inverter output and the grid is presented. Detailed researches of PV system were carried out by means of the mathematical simulation. The researches disclosed dependence of the system reactive power on the phase of sinusoidal modulation voltage of the inverter. It is defined that phase of the modulation voltage must be positive and can vary in the range 0÷20 degrees. Researches show that researched PV system can generate the capacitive reactive power for compensation of the inductive reactive power of the grid. Operation mode of the system when the reactive power is equal to zero can be achieved in this system. It is defined that electromagnetic distortion (THD) of the grid has maximal value at the point when the reactive power is equal to zero. Consequently, this feature must be evaluated at the design of the inverter filter.

Simulation and Implementation of Power Control Strategy Grid Connected Photovoltaic System

2015

This paper introduces a direct power control strategy for a grid-connected voltage-source inverter. The proposed control strategy is implemented in the stationary reference frame without the necessity of the synchronous d-q transformation. The proposed control strategy based on the deadbeat current control technique and the relations between the grid currents and the instantaneous active and reactive power in the stationary reference frame. Then, the required inverter voltage in α-β reference frame is calculated directly based on instantaneous errors of active and reactive power. For its advantages, space vector modulation (SVM) is chosen to generate the VSI gating signals. Due the simplicity of the proposed control strategy, a fixed point microcontroller is used for control implementation. Extensive simulation and experimental results are provided which confirm the validity of the proposed control technique.

Reactive Power Compensation of the Grid Connected PV System

HELIX, 2019

Renewable energy has been a subject of research owing to the continuous environmental concerns across the globe. The overall power factor of the power systems is reduced due to DC energy fed to the grid using electronic energy inverters. Increased grid load due to poor power factor triggers losses in the grid. Active and reactive power can be produced by proper control of multistage inverters. Instantaneous reactive power theory enables the control of the active currents and reactive currents of the inverter by regulating the amplitude and phase angle of the inverter. This paper deals with the instantaneous reactive power theory by implementing the hysteresis current controller. The proposed control scheme consists of instantaneous reactive power theory (IRPT) based on the current source inverter (CSI) to suppress harmonic currents and reactive power compensation. Improvement of the power factor through compensation of the reactive power at an ideal level was attempted using the control system of grid-connected photovoltaic systems. The effectiveness of the proposed control strategy was implemented with the help of simulation using MATLAB/SIMULINK.

CONTROL AND ANALYSIS OF GRID-CONNECTED PV SYSTEM USING CURRENT CONTROL TECHNIQUES OF INVERTER

IJARW, 2022

Solar photovoltaic is one of the most promising renewable energy sources that converts solar energy into electricity in an environmentally friendly way. However, the efficiency is low and the relative costs are high. To overcome these drawbacks, a grid-connected photovoltaic system must be required to meet the load demand. In this paper, the analysis and simulation of a single-stage grid-connected photovoltaic system using the hybrid inverter and its control methods for implementing DC to AC power conversion are presented. The design of a single-stage grid-connected photovoltaic system by modeling and simulation of hybrid inverters is carried out in the MATLAB-Simulink environment. A fixed DC i/p voltage is supplied using the PV module to the hybrid inverter and a controlled AC o/p power is obtained by adjusting the value of Id and Iq, thus varying the on/off periods of the l hybrid inverter. components.investor. The hybrid inverter used in this article features a single-phase version of SSI with enhancements to the PWM inverter topology. the fundamental frequency to raise the input source voltage into the intermediate circuit voltage. In this inverter, one of the full-bridge arms is subject to a constant duty cycle change, while the other is subject to a sinusoidal variable duty cycle change. The variation of the duty cycle is obtained using a pulse width modulation [PWM] generator block. Therefore, by varying the value of Id and Iq, the active and reactive o/p power can be proscribed using the decoupled current control method in the hybrid inverter.