scholarly journals Power Quality Enhancement in Grid Connected PV Systems using High Step Up DC-DC Converter

Author(s):  
V S Prasadarao K ◽  
K V Krishna Rao ◽  
P Bala Koteswara Rao ◽  
T. Abishai

Renewable energy sources (RES) are gaining more importance in the present scenario due to the depletion of fossil fuels and increasing power demand. Solar energy is the one of the most promising as it is clean and easily available source. The voltage obtained from the PV system is low. This voltage is increased by high step up dc-dc converter which uses only one switch leads to low switching losses and hence the efficiency of this converter is high. To get the good response this converter is operated in closed loop manner. Integration of PV system with existing grid has so many issues like distorted voltage, current and reactive power control etc. This paper presents a four leg inverter which works on hysteresis current control technique to address the power quality issues like reactive power compensation, balanced load currents and compensation of neutral current. The switching to the inverter is designed in such a way that it supplies the extra current to stabilise the current of the grid that is being supplied to the loads. Finally, the proposed technique is validated by using mat lab/Simulink software and corresponding results are presented in this paper.

2013 ◽  
Vol 385-386 ◽  
pp. 1224-1228
Author(s):  
Yun Liang Wang ◽  
Qi Liang Guo

In this paper, the hysteresis current control (HCC) technique based on space vector modulation (SVM) for active power filter (APF) is proposed. The switching control algorithms of the HCC based SVM manage to generate compensated current according to the reference current. Harmonics extraction is calculated for the power compensation based on the instantaneous active and reactive power theorem in time domain. A closed loop control system is carried out and the APF manages to generate better compensated harmonics currents to the power grid.


2014 ◽  
Vol 15 (3) ◽  
pp. 263-277 ◽  
Author(s):  
Nagesh Geddada ◽  
Srinivas B. Karanki ◽  
Mahesh K. Mishra

Abstract This paper proposes a modified four-leg distribution static compensator (DSTATCOM) topology for compensation of unbalanced and nonlinear loads in three-phase four-wire distribution system. DSTATCOM, connected in parallel to the load, supplies reactive and harmonic powers demanded by unbalanced nonlinear loads. In this proposed topology, the voltage source inverter (VSI) of DSTATCOM is connected to point of common coupling (point of interconnection of source, load, DSTATCOM) through interface inductor and series capacitance, unlike the conventional topology which consists of interface inductor alone. Load compensation with a lower value of input DC link voltage of VSI is possible in this modified topology compared to conventional topology. A comparative study on modified and conventional topologies in terms of voltage rating of inverter power switches, switching losses in VSI and power rating of input DC capacitor of VSI is presented. The detailed design aspects of DC link capacitor and interface series capacitor are also presented. The reference filter currents are generated using instantaneous symmetrical component theory and are tracked using hysteresis current control technique. A detailed simulation study is carried out, to compare the compensation performances of conventional, modified topologies using PSCAD simulator and experimental studies are done to validate the simulation results.


Author(s):  
P Hari Pallavi and P Ankineedu Prasad

Grid-connected photovoltaic (PV) systems are increasingly attracting the attention of industry and academia as a means of providing an alternative to conventional fossil-fuel generation and pollution-free power. This project aims to improve the power quality level of a grid-tied PV distribution system using shunt active power filter (APF) along with adaptive current control technique. In this work Artificial Neural Network controller used to destroy the voltage and current harmonics in a grid-tied PV system. A reference current generation strategy is implemented to mitigate the current harmonics by extracting the fundamental constituents (FCs) from the nonlinear load currents. MCCF is employed to separate the FC from the distorted grid voltages and eliminates the voltage harmonics during extremely polluted grid voltage condition. The comparative analysis is analyzed to check the effectiveness of the proposed hybrid control scheme with existing and adaptive control techniques in respect of power quality, better dc offset rejection, better FC and frequency extraction, and grid synchronization.


Author(s):  
B Anand Swaroop and K Jagadeesh

Grid-connected photovoltaic (PV) systems are increasingly attracting the attention of industry and academia as a means of providing an alternative to conventional fossil-fuel generation and pollution-free power. This project aims to improve the power quality level of a grid-tied PV distribution system using shunt active power filter (APF) along with adaptive current control technique. In this work Fuzzy Logic controller used to destroy the voltage and current harmonics in a grid-tied PV system. A reference current generation strategy is implemented to mitigate the current harmonics by extracting the fundamental constituents (FCs) from the nonlinear load currents. MCCF is employed to separate the FC from the distorted grid voltages and eliminates the voltage harmonics during extremely polluted grid voltage condition. The comparative analysis is analyzed to check the effectiveness of the proposed hybrid control scheme with existing and adaptive control techniques in respect of power quality, better dc offset rejection, better FC and frequency extraction, and grid synchronization.


This Paper presents a control strategy of the grid interconnected inverter Renewable Energy Sources (RES). This system can achieve the maximum benefits from these grid interconnected inverter when installed in 3-phase 4-wire distribution system. Increasing electrification of daily life causes growing electricity consumption and the rising number of sensitive or critical loads demand for high quality electricity. One of the main problems facing today is that related with the transmission and distribution of electricity. Due to the rapid increase in global energy consumption and the diminishing of fossil fuels, the customer demand for new generation capacities and efficient energy production, delivery and utilization keeps rising. Utilizing distributed generation, renewable energy and energy storage can potentially solve problems as energy shortage. With the increase in load demand, the Renewable Energy Sources (RES) are increasingly connected in the distribution systems which utilizes power electronic Converters/Inverters. The inverter can perform as a multi function device by incorporating active power filter functionality. The inverter can thus be utilized as: 1) power converter to inject power generated from RES to the grid, and 2) shunt APF to compensate current unbalance, load current harmonics, load reactive power demand and load neutral current. All of these functions may be accomplished either individually or simultaneously. This new control concept is demonstrated with extensive MATLAB/Simulink simulation studies and validated through digital signal processor-based laboratory experimental results.


Author(s):  
P Hari Pallavi and P Ankineedu Prasad

Grid-connected photovoltaic (PV) systems are increasingly attracting the attention of industry and academia as a means of providing an alternative to conventional fossil-fuel generation and pollution-free power. This project aims to improve the power quality level of a grid-tied PV distribution system using shunt active power filter (APF) along with adaptive current control technique. In this work Artificial Neural Network controller used to destroy the voltage and current harmonics in a grid-tied PV system. A reference current generation strategy is implemented to mitigate the current harmonics by extracting the fundamental constituents (FCs) from the nonlinear load currents. MCCF is employed to separate the FC from the distorted grid voltages and eliminates the voltage harmonics during extremely polluted grid voltage condition. The comparative analysis is analyzed to check the effectiveness of the proposed hybrid control scheme with existing and adaptive control techniques in respect of power quality, better dc offset rejection, better FC and frequency extraction, and grid synchronization.


2020 ◽  
Vol 29 (16) ◽  
pp. 2050256 ◽  
Author(s):  
B. N. Ch. V. Chakravarthi ◽  
G. V. Siva Krishna Rao

In grid-connected solar PV system, power quality gets affected seriously due to the variable real power penetration. The transformer is mandatory to integrate and isolate the solar PV and powered network. However, due to presence of this transformer, size and cost of the entire solar PV station get increased and it requires more space while supplying poor quality of power. In order to overcome this drawback, this paper proposes a double boost integrated multilevel inverter to inject the power into utility grid. In addition, the optimal control strategy is used to tap maximum power generation from solar PV and injected into grid with improved power quality. This paper presents an adaptive digital hysteresis current control approach to penetrate optimal power into grid. To validate the proposed work, the simulation results are carried out using PSCAD/EMDTC software. Furthermore, to confirm theoretical study and simulation study, the experimental test was performed and detailed results with validation were presented in this paper.


Energies ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 331
Author(s):  
Safa Haq ◽  
Shuvra Prokash Biswas ◽  
Md. Kamal Hosain ◽  
Md. Ashib Rahman ◽  
Md. Rabiul Islam ◽  
...  

Due to global warming and shortage of fossil fuels, the grid-connected solar photovoltaic (PV) system has gained significant popularity all over the world. The modular multilevel cascaded (MMC) inverter is the natural choice for step-up transformer and line filter less direct medium voltage grid integration of solar PV systems. However, power quality and loss are the important issues while connecting the PV system to the medium voltage grid through MMC inverter. Modulation technique is the key to maintain output power quality, e.g., total harmonic distortion (THD) and to ensure low switching and conduction losses. In this paper, an advanced modulation technique named “triangle saturated common mode pulse width modulation (TSCMPWM)” control is proposed for a 3-phase 5-level MMC inverter-based grid-tied PV system. Compared to traditional modulation techniques, the proposed TSCMPWM control offers the lowest voltage THD as well as lower inverter power losses. Performance of the proposed modulation technique is evaluated in MATLAB/Simulink environment and tested with a reduced scale prototype test platform. Both simulation and experimental results show the effectiveness of the proposed modulation technique.


Author(s):  
CH. Sri Prakash ◽  
G. Kesava Rao ◽  
Obbu Chandrasekhar ◽  
P. V. Satyaramesh

Distribution Generation plays a significant role in remote areas where the utility grid is affected and initializing by renewable energy sources to acquire the sufficient power demand. In distribution system, it is very exigent consumer related concern which is confronted due to mis-operation of massive non-linear load apparatus. A multi-functional distributed static compensator incorporates the best choice for enhancing the power quality features with effective control scheme under rambled non-linear loads. Conventional control schemes are more adversed with greater switching losses due to extreme harmonic frequencies in a refernce current component. This paper proposes, a novel multi-objective fundamental reference current control scheme based multi-functional DSTATCOM furnishes the current harmonic compensation at PCC, reactive power compensation, power factor correction, active power exchanging, minimizing the switching losses, incredible efficiency and power factor correction. The validation of proposed multi-functional DSTATCOM with proposed control strategy under rated capacity of distribution generation is evaluated by using Matlab/Simulink platform and simulation results are presented.


Sign in / Sign up

Export Citation Format

Share Document