• What is MPPT and why it is needed? (Maximum power point tracking)It is needed a controller (MPPT) to achieve the highest efficiency and provide a stable power under the intermittent weather condition
• Why IC technique ?It shows good performance under the intermittent of solar irradiance
The simulation result will show how good is the performance of this IC technique.
PV Model• A solar cell basically is a p-n semiconductor
junction. When exposed to light, a dc current is generated.
PV Characteristic
IC MPPT Technique• The incremental conductance method is
developed under the fact of slope of the PV array power curve is zero at the MPP
IC MPPT Algorithm
Block Diagram of the Proposed PV System
PV ARRAY
BOOSTCONVERTER
PVINVERTER
3-PHASEGRID
IC MPPT CONTROL
I
V
PV INVERTERCONTROL
AC
DCDC
SIMULATION SYSTEM
Under mask the system
Simulation under constant solar irradiance• The maximum standard operating for constant solar irradiance is assumed
to be 1000 W/m2 in the study.
(A) The measured output of PV Module (B) The respond of IC MPPT tracking algorithm
Under 1000 W/m2 of solar irradiance, The duty cycle for boost converter is a constant value 0.45 and the booster convert around 92kW of power with constant ouput voltage 500 V to the PV inverter.
Output from boost converter
The PV module provides 100kW and the boost converter convert 92kW of energy
Comparison of the measured output of PV module with output of boost converter
Simulation under decreasing solar irradiance
(A) Decreasing of solar irradiance (B) Duty cycle of boost converter
The figure shows the decreasing solar irradiance (1000 W/m2- 800 W/m2 -250 W/m2).
(A) The measured output of PV Module (B) The respond of IC MPPT tracking algorithm
The figure shows the power, voltage, current of boost converter. Under (1000 W/m2- 800 W/m2 -250 W/m2) of solar irradiance, the booster convert around 92kW - 80 kW - 25 kW of power. The
booster maintains the output of voltage to be 500 V to the PV inverter.
Output from boost converter
The PV module provides 100kW (1000 W/m2) 80kW (800W/m2) 25kW (250 W/m2) and the boost converter convert 92kW, 74kW, 20 kW
Comparison of the measured output of PV module with output of boost converter
Simulation under different solar irradiance
Figure B shows the duty cycle of boost converter responding to different solar irradiance. In fact, an extreme variation of solar irradiance occur rarely.
The figure A shows the variations of solar irradiance (600 W/m2- 800 W/m2 - 400 W/m2 -600 W/m2)
(A) The measured output of PV Module (B) The respond of IC MPPT tracking algorithm
The figure shows the measurement output from boost converter. The figure shows the power, voltage, current of boost converter. Under (600 W/m2- 800 W/m2 - 400 W/m2 -600 W/m2) of solar irradiance, the booster maintains output voltage to be 500 V constantly.
Output from boost converter
The power efficiency is approximately 90%. The simulation result shows the MPPT works and respond fast and well even in any behavior of solar irradiance and also gain a high efficiency
Comparison of the measured output of PV module with output of boost converter
PV module connected to gridThe simulation is under 1000 W/m2 of solar irradiance.
Output voltage of PV Inverter
Output voltage of load
The figure shows the voltage after connected to the grid. to phase A-B in 25 kV voltage level.
Output voltage of grid