Multi-inductor Parameters Identification and Power Decoupling Control in Induction Heating Power Supply

To solve the problems of gradient heating and power control in irregularly shaped metals, we design a three-sensor induction heating power process, which has three segments and joint-induction coil heating. We establish a mathematical model and identification method based on key parameters, such as frequency, power, and heating time in aluminum. We also studied the coupling problem by analyzing the heating equivalent circuit for a three-sensor power supply, which obtains the same phase of a three-section multi-sensor output current as the key to power decoupling. Using this theory, we developed a simulation model and prototype, and the simulation results show that using the recursive least squares parameter estimation algorithm will result in a good identification model. This system reaches the allowable error limit when the frequency and heating power have reached 300 and 1 000 recurrence times, respectively. Prototype experimental results show that this method effectively eliminates power coupling between segments of the induction coil, and that accurate gradient heating and power control of irregularly shaped metals can be achieved.