Influence of Mechanical Speed on Generator Voltage

The increase in population and the pollution is the biggest issue that world is facing, the use of conventional fuels is the key problem of pollution around the world. Majority of countries ae moving to the non pollutant energy sources. The use of solar is on the top, while the use of wind is also increasing day by day. The sun is the main foundation of energy for the photovoltaic which converts heat energy into electricity. Wind is use to drive the rotor of the wind turbine which converts kinetic energy to electrical energy. Both the sources are subjected to uncertainties due to variation in atmospheric parameters. The actual output from PV and wind is dependent on the certain conditions, that is known as capacity factor. The capacity factor of WT is around 20-40% while in case of PV its around 12-15%. However it always dependent on the location, wind speed, solar irradiation and temperature of that particular location [2]. The solar power available during day time and peak during afternoon periods while the wind power is available most of the time specially during night due to high wind velocity [7]. tIntpractice,tthis impliest thet  possibility toftforming tathybrid tpowertsystemt totmediatetthetpowertimbalances,  withtthet PVtcells  tprovidingtelectricitytduring the tday tand  twindtprovidingt electricitytat night in wintertandtsummertseasons.

Efficiency of inverter is defined as the how much power from DC is converted into the AC power losttastheat,tandtalsotsometstand-bytpowertistconsumedtfor keeping the inverter in poweredtmode.tThetgeneraltefficiency formula is

The rotor current of DFIG is controllable by the dual stage converter stage, still any change in rotor current affect the stator voltage as the current in the rotor winding changes the flux of rotor and the induced voltage on stator terminal also get affected. To smoothly control the stator voltage of the DFIG the rotor fed control from converter must be implemented.

As the frequency of rotor varies the stator frequency also changes, two factor are important for stator frequency one is the mechanical speed of rotor and second is rotor frequency. Mechanical speed can be controlled by gear box arrangement still perfect control is not possible while the rotor frequency can be controllable from the converter stage. Any change in rotor frequency will leads to change in stator frequency.

The rotor current of DFIG is controllable by the dual stage converter stage, still any change in rotor current affect the stator voltage as the current in the rotor winding changes the flux of rotor and the induced voltage on stator terminal also get affected. To smoothly control the stator voltage of the DFIG the rotor fed control from converter must be implemented.

Influence of Variable Rotor Frequency on Stator Frequency

The full report is attached below designed using PVsyst utilized in evolution mode.

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