3-terminal bidirectional switching power supply with AC or DC input and AC or DC output

摘要

The bidirectional switching power supply has high output power, high efficiency, high reliability and very small size. One device operates as DC/DC, DC/AC, AC/DC or AC/AC converter. Short circuit protection is inherent. The switching power supply can be carried out in integrated form as 3-terminal device. Additional terminals can be established for reference and control signals. Numerous standard devices can be built by adding just a few components, possibly no power semiconductors. The switching power supply comprises an inductor which has a pair of terminals and attains a current. Three unidirectional switches are coupled to one terminal for selectively applying the current to the input, ground and output. Two other unidirectional switches are coupled to the other terminal for selectively applying the current to ground and output. A diode or unidirectional switch can be coupled to the other terminal for applying the current to the input. Regardless of the configuration and polarities of the input and output voltages, the inductor current flows in one direction.