The transmission apparatus (1) has a power interface (2) which is coupled to one voltage domain, where another power interface (3) is coupled to another voltage domain. A detecting medium (4) detects the state of charge (SOC) of an energy storage of the latter voltage domain. A direct current-to-direct current converter (5) is connected between the former power interface and latter power interface. The converter is designed to transfer electric power from the former voltage domain to the latter voltage domain in response to the detected state of charge. An independent claim is included for a method for transferring electric energy in an electric vehicle with two voltage domains.

Transmission apparatus for electric vehicle two voltage domains, has direct current-to-direct current converter that is connected between power interfaces, and transfers electric power from one voltage domain to another voltage domain

The direct voltage converter for transferring charge between batteries of different terminal voltages has a static inverter coupled via a transformer to a rectifier. The static inverter consists of four semi-conductor controlled rectifiers (23-26) connected to form a bridge with a capacitor (28) in one diagonal. The rectifier is so poled that it supplies current to one battery when the transformer (12) magnetic field collapses. The controlled rectifiers are controlled from a variable frequency oscillator (31), which is itself controlled (40) in conjunction with the rectifier output voltage. The advantage of this converter arrangement lies in its giving maximum reliability and optimum energy transfer.

Habasch Ahmed

Papers

DC voltage converter for battery charge transfer - has rectifier, transformer and static inverter with four SCRs