สายชล ชุดเจือจีน. LLC Resonant Inverter for Induction Heating Applications. Doctoral Degree(Computer Engineering). King Mongkut's University of Technology Thonburi. KMUTT Library. : King Mongkut's University of Technology Thonburi, 2011.
LLC Resonant Inverter for Induction Heating Applications
Abstract:
inverter for induction heating applications. The LLC load configuration is a
combination of a series inductor, a matching transformer, and an inductor and a
capacitor connected in parallel. The proposed control is a modification of the classical
LLC load by moving the series inductor to the primary winding of the matching
transformer. The proposed configuration has the benefit of smaller inductance and
inherent short-circuit protection capability in case that the short circuit occurs at the
induction coil or from transformer saturation. The output power is controlled by using
the asymmetrical voltage cancellation technique. With the use of a phase-locked loop
control, the operating frequency is automatically adjusted to maintain the desired
constant lagging phase angle under load parameter variation during the heating process.
The proposed technique has the benefit of tum on switching loss being zero through
zero voltage switching. A design procedure is presented that covers the LLC load
configurations in the case of low quality factor (Q < 10). The validity of the proposed
method is verified through computer simulation and hardware experiment at the
operating frequency of 108.7 to 110.6 kHz. A correlation between theory, computer
simulation and the experiment has been observed.