Abstract
This paper presents an improved selective harmonics elimination
technique for PV assisted single phase
grid-tied pulse width modulated (PWM) voltage source
inverter (VSI). The switching angles are determined offline
through numerical techniques and stored in microcontroller
memory as a function of modulation index md for online
application. For multiple solution, the solution which leads to
lower change of switching angles (α) from the previous md, is considered
for storing in the processor memory. This leads to less no. of sections
for the processor when a piecewise mixed model is considered for storing
the entire switching angle curve. This technique is well suited for
limiting voltage THD in two level grid connected VSI with L-C filter.
The verification of theoretical concept is done in laboratory prototype
of PV (500 W) connected to grid-tied PWM inverter. The control
environment is realized in embedded FPGA interfaced national instrument
hardware.