Small size and low weight DC/DC converter with no magnetic elements

A new type of DC power supply containing no inductors or transformers is presented. The DC-to-DC boost power converter contains only switches and capacitors. The switching-capacitor circuit is used for controlling the DC energy transfer from an unregulated input voltage to a regulated output. The output voltage is kept constant despite large variation in the input voltage or load. The power converter operates at a constant switching frequency, the regulation being of PWM type. The operation of the main switches in the energy flow path is dictated by the output of a PWM chip. The absence of magnetic elements in the power converter structure guarantees an overall small size, low weight and high power density. The design of the circuit parameters (capacitor values and switching frequency) assures minimum losses of energy at the switching moments. The transient currents have nondangerous peaks; consequently, no overrating of the transistors is necessary, assuring small conduction losses. As a result, the new power converter presents high efficiency. Experimental results, obtained on a prototype built according to the exposed design procedure, are presented