Constant DC Current Source Using Asymmetrical SRC Operated in Discontinuous Conduction Mode

This paper presents a converter that provides constant output current. This converter is implemented by using asymmetrical series resonant converter (SRC) operated in discontinuous conduction mode (DCM) with variable switching frequency control. It is shown in the paper the output current only depends on input voltage and switching frequency. Hence, the load condition does not have any effect on the load current during steady state. However, there is one condition that the output voltage has to be lower than the input voltage. In addition, the proposed converter also provides common ground between input and output. With diode configuration setting at the output, the proposed converter has a capability to be selected for noninverting (positive) and inverting (negative) output. Common ground is still remained for both configurations. State-plane diagram representing steady state response of the converter is presented. It is also shown that the proposed converter during steady state is also analyzed by utilizing state-plane diagram technique. Example for converter design is also presented together with computer simulation that confirms the analytical work.