ABSTRACT
This chapter introduces a three-element current source resonant inverter (CSRI): Π-CLL CSRI consists of three energy-storage elements CLL, the ΠCLL. A bipolar current source is employed in this circuit as described in the previous chapter and shown in Figure 13.7. Since there is no transformer and the circuit is not working in push-pull operation, the control circuit is very simple and power losses are low. This Π-CLL CSRI is shown in Figure 14.1. The energy source is a DC voltage Vin, which is chopped by two mains switches S1 and S2. The three energy-storing elements are C, L1 and L2. Two inductors can be different, i.e., L2 = p L1 with p as a random value. The load can be a coil, transformer or HF annealing equipment. A resistance Req is assumed. Its equivalent circuit diagram is shown in Figure 14.2.
