A series tuned high power IPT stage lighting controller

Abstract

Traditional stage lighting systems inherently suffer significant cost in materials/installation and can be affected by audible noise when operating at mains frequency. A new circuit for stage lighting is introduced to mitigate these issues; it comprises a series tuned IPT pickup with a new AC control topology. This topology builds on previous work by improving the waveform across the load & pickup and by lowering the switch ratings. The circuit is analyzed, simulated and a working system is measured and presented herein, including the relationship between the switch and the reactive elements for the design. A 1.2 kW 240 V Philips Broadway lamp is successfully powered by this controller. The waveforms across the load are sinusoidal which lower the peak values for a given RMS voltage or current level, reducing noise and simplifying the design. The output voltage is regulated to 1% by implementing closed loop control on the system.