Priyank Shah

Optimal control scheme for single stage grid interfaced SECS for power quality improvement

This paper presents an improved generalized integrator based control scheme with a frequency locked loop for multifunctional single stage three phase grid interfaced solar energy conversion system (SECS) for power quality improvement of the distribution network. The perturb and observe (P&O) based maximum power point tracking (MPPT) algorithm is used to obtain crest power from solar photovoltaic (PV) array under varying atmospheric conditions. The control scheme serves unity power factor operation, load balancing, harmonics mitigation and reactive power compensation. The improved generalized integrator control scheme has an advantage of better DC offset and harmonics rejection capabilities as compared to a conventional second order generalized integrator (SOGI) algorithm. To validate the control scheme, tests are performed on a developed prototype in the laboratory for various operating conditions. Test results show the satisfactory behaviour under steady state and dynamic conditions such as load unbalance, insolation variation, voltage sag and swell. The THDs (Total Harmonic Distortions) of grid currents and voltages are found within limits of grid code compliance of an IEEE 519 standard.

ISOGI-Q based control algorithm for single stage grid tied SPV system

This paper deals with a single stage solar photovoltaic (SPV) array tied with a three phase grid by using an improved second order generalized integrator quadrature signal generator (ISOGI-QSG) based control algorithm to improve power quality of the grid. The maximum point power tracking (MPPT) is achieved by using an incremental conductance method. The incremental conductance MPPT method is effective to extract maximum power from a SPV array as well as to regulate the DC link voltage. ISOGI-QSG based control algorithm is robust and enhances the power quality in terms of load balancing, noise elimination and power factor correction (PFC) very effectively. Having D-STATCOM capabilities of SPV based system is useful to supply the active power to grid as well as to loads. The control algorithm is verified on proposed system topology and obtained responses are found satisfactory and total harmonic distortion (THD) of source currents within standard limit.

FOGI-QSG based control of multifunctional grid tied SECS

This paper deals with a solar energy conversion system (SECS) interfaced with three phase grid using a fourth order generalized integrator quadrature signal generator (FOGI-QSG)based control algorithm, which helps to mitigate the power quality problems like power factor correction, load balancing, harmonics elimination and noise cancellation. The perturb and observe (P&O) based maximum power tracking point (MPPT) algorithm is used to extract the maximum power from solar photovoltaic (SPV) array. The reference voltage is obtained from MPPT algorithm which helps to maintain DC link voltage of a voltage source converter (VSC). The FOGI-QSG based control algorithm is an easily realizable without compromising accuracy. The control algorithm is validated experimentally on developed hardware in the laboratory. Total harmonic distortion of source current of distribution network has been found within limit according to an IEEE-519 standard at common coupling point.

Single stage SECS interfaced with grid using ISOGI-FLL based control algorithm

This paper deals with the solar energy conversion system (SECS) tied to a three phase grid by using an improved second order generalized integrator with frequency locked loop (ISOGI-FLL) based control algorithm to mitigate the power quality problems. The steepest descent maximum power point tracking (MPPT) algorithm is used to extract the maximum power from solar photovoltaic (SPV) array to increase the efficiency of system as well as to maintain DC link voltage of the voltage source converter (VSC). The ISOGI-FLL based control algorithm is very effective to mitigate power quality problems like harmonics, load unbalancing and poor power factor of the grid while supplying an active power to the grid. Experimental results on developed prototype have verified satisfactory operation of proposed topology for different conditions like load unbalancing, SPV (solar photovoltaic) to DSTATCOM (distribution static compensator) mode, DSTATCOM to SPV mode at variable solar insolation. Moreover, total harmonic distortions (THDs) of grid currents are found within limit of an IEEE-519 standard.