Control model of a closed loop power-controlled series-type resonant induction heating system

This work presents the mathematical modeling of a power controlled, resonant operated inductive heating system. Experimentally the power is measured over the heating coil and processed to have the real power as a feedback signal that manages a pulse density (delta) modulator topology with a PID compensation network. The results shows that it is possible to directly control the real output power of the inverter, opening the possibility to obtain information about the energy transferred to the load in situations where this is critical, for example, in precise heating processes.

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