Adiabatic charging of capacitors by Switched Capacitor Converters with multiple target voltages

A method for adiabatic charging of a capacitor by Switched Capacitor Converters (SCC) with multiple target voltages is presented, analyzed and verified experimentally. The SCC automatically changes the target voltages from low to high and back, thereby emulating voltage steps. This reduces the energy losses due to small voltage deviations between the SCC output and the charged capacitor and by enabling the stored energy to be recovered back into the power supply. In comparison with the previous method a considerable economy in hardware is achieved by replacing a set of voltage sources by a single SCC. It is shown that the voltage source and the switch resistance in the regular charging circuit can be emulated by the SCC equivalent circuit. Furthermore, such emulation provides the same step response if the SCC is operated close to the no-charge (NC) mode. This theoretical prediction was approved experimentally using the binary SCC.