scholarly journals Decoupled Control of Three Phase Grid Connected Solar PV System

A reliable grid connected Photovoltaic (PV) system require effective control schemes for efficient use of solar energy. This paper presents a three-phase grid tied PV system with decoupled real and reactive power control to achieve desired power factor with Maximum Power Point Tracking (MPPT) controller to get maximum solar energy. The synchronous reference frame (dq) control along with decoupling concept is used to control the DC-AC inverter output, while the Phase Locked Loop (PLL) synchronization technique is used to monitor and synchronize the voltage and current at the grid side. The DC-DC converter with Incremental Conductance (InC) based MPPT model is also designed in this paper due to better accuracy compared to Perturb & Observe (P&O) algorithm. The simulation is performed in MATLAB/SIMULINK and a 31.5 kW PV system is modelled to get 30 kW power with the help of MPPT at Standard Test Conditions (STC). Any power factor value between 0.85 lagging to 0.9 leading can be obtained by changingreference q current in this inverter control strategy. The simulation results show that the change of reactive powerdoes not affecttheactive power values of the system, which verifies the effectiveness of the decoupled control strategy of the inverter.

2013 ◽  
Vol 336-338 ◽  
pp. 450-453
Author(s):  
Jian Ying Li ◽  
Wei Dong Yang ◽  
Ni Na Ma

In view of the fact that active power and reactive power have coupling relation, a novel vector decoupling control strategy is presented for three-phase voltage source PWM rectifier. In the paper, the power control mathematical mode of the PWM rectifier is deduced based on the mathematical model of rectifier in synchronous d-q rotating coordinates, and a new voltage feed forward decoupling compensation control strategy is proposed. The simulation results show that the voltage and current of the three-phase PWM rectifier have better respond preference, the current aberrance is smaller and the voltage is steady under the control strategy. The PWM rectifier can implement PWM commute with unity power factor, but also feed back the energy to AC side with unity power factor.


2020 ◽  
Vol 182 ◽  
pp. 02011
Author(s):  
WAN Qian ◽  
Xia Chengjun ◽  
Azeddine Houari ◽  
Zhao Xue ◽  
Xia Chengjun ◽  
...  

Renewable energy sources (RESs) generally connected with electric power system via power electronic interface. This paper presents a reactive power and voltage (Q/V) control strategy of three-phase photovoltaic (PV) system to offering reactive power based on the typical dual-loop control topology. It is worth mentioning that control strategy can support reactive power when a low voltage fault occurs in AC bus without additional compensation device. With the help of the decoupling control, the PV array can generate active power as much as possible in variable external solar radiation conditions. The voltage of PV arrays is adopted as the objective, which on account of the easy availability and controllability of voltage, to control output active power. Besides, accurately modeling process from a PV cell to PV array is described in the beginning to acquire the P-V and V-I characteristics of PV arrays, which promote the designment of Q/V control.


2020 ◽  
Vol 167 ◽  
pp. 05005
Author(s):  
Elsayed Saad ◽  
Yasser Elkoteshy ◽  
Usama AbouZayed

Recently, solar-PV energy becomes one of the most vital renewable resources of electrical energy as it is utilized in all life applications. In case of connecting the solar-PV system with the utility grid a voltage-sourced converter (VSC) is required to convert the extracted solar-PV array’s DC power into AC. There are many methods to dominate the active and reactive power produced from the VSC. In the following model we use the current mode control as it has some features such as highly output accuracy, protection against over current troubles, robustness against AC side voltage and load variations. As the produced power from the solar cells is intermittent, the point of maximum power has to be tracked using an MPPT technique. Also, in order to reduce the system harmonics a filter must be implemented in the model. In this paper, a complete model of 50KW grid-connected solar-PV system using current-mode controlled two-level three-phase VSC (grid imposed frequency VSC) is implemented. Also, the Incremental Conductance model to track the point of maximum available power (MPPT) and LCL filter has been provided into the system with total harmonic distortion (THD) analysis in PSCAD/EMTDC


Author(s):  
Namratha Sampath ◽  
P.V.S.S.A Parimala

The set of restrictions defined for a system's electrical characteristics so that the entire electrical system can function in the intended manner and without losses is known as power quality. Power quality issues such as transients, harmonics, voltage swell, sag, flicker, fluctuations, and power factor difficulties are becoming more common as power electronic devices become more widely used. The usage of a Distribution Static Compensator (D-STATCOM) to mitigate power quality issues is discussed in this study. In this case, D-STATCOM functions as a shunt active power filter to reduce harmonics caused by non-linear loads. The simulation studies on a PV-based Cascaded-H-Bridge Multi-Level Inverter i.e Solar PV and Cascaded H Bridge MLI are integrated using Selective Harmonic Elimination method with D-STATCOM injected at the load side to improve power quality are presented in this project. The Solar PV system is mathematically modelled using Boost regulator and P&O MPPT technique and to the D-STATCOM the controller is designed utilizing Synchronous Reference Frame Theory (SRFT) out of many control strategies for reactive power compensation, harmonic mitigation, and power factor enhancement as it is more accurate. A 2nd order low pass filter is employed at the load side to reduce the harmonics to some extent, and both 5-level and 7-level models are evaluated. MATLAB/SIMULINK is used for simulation.


2021 ◽  
Vol 309 ◽  
pp. 01124
Author(s):  
Srinivasa Rao Jalluri ◽  
Ramesh Babu Veligatla ◽  
Ranjit Mahamkali ◽  
Purushothama Raghavendra Reddy Gogireddy

Solar energy is among the abundant forms of energy, it is very important to make the best use of it. But intermittent nature of solar energy makes PV generation unreliable at times. The use of a battery as an energy storage device can help to mitigate this problem to some extent. A Bidirectional DC-DC converter must be used to connect the battery to the DC link in order to maintain a steady voltage. DC link then connected to a load. In this paper, P&O MPPT technique used to get maximum power from PV array. Fuzzy logic control is used for the effective control of Bidirectional DC-DC converter to charge and discharge battery to keep the DC link voltage constant. Simulations are carried out using MATLAB and outcomes are analysed.


2014 ◽  
Vol 533 ◽  
pp. 397-400 ◽  
Author(s):  
Chi Jui Wu ◽  
Yu Wei Liu ◽  
Shou Chien Huang

To modify the power factor and balance the three-phase currents simultaneously, this paper proposes the instantaneous compensator to calculate the compensation current. The instantaneous compensator utilizes two-dimensional instantaneous space vector and setting the active power as a constant for each cycle which can improve power quality effectively. Moreover, the instantaneous compensator requires an independent power source, whose capacity can be reduce by using a static var compensator (SVC). An SVC does not interfere with the capability of the instantaneous compensator. Field measurement data were analyzed. Simulation results confirmed the feasibility of correcting the power factor and balancing load currents simultaneously using the proposed method.


Sign in / Sign up

Export Citation Format

Share Document