5. POWER CONTROL BY INTEGRAL CYCLE SWITCHING WITHOUT GENERATING HARMONICS

we are using a comparator for zero crossing detection which is fed as an interrupt to the microcontroller of 8051 family. Here, the microcontroller delivers the output based on the interrupt received as the source from which triggering pulses are generated .In order to provide integral cycle control in accordance with the input switches interfaced to the microcontroller, we use these pulses to drive the opto- isolators, which in turn trigger the TRIAC. To validate the output, a series motor or lamp can be utilised instead of a linear load to be employed in the outp ut.An imbalance in the input current or voltage waveform as the cycles are turned on and off is one consequence of using this approach. off across the load. A lamp is provided in this project in place of a motor for demonstration purpose. The project output with a lamp appears to be a simple project of lamp flickering but the real objective is to verify in a CRO/DSO ,whether at the random switching also the load switches on at zero cross of the waveform or not.