Realization of a multiple resonant DC-link converter

The realization of a passively clamped resonant DC-link converter containing both a three-phase controlled rectifier and a DC-motor drive is presented. The control electronics are described, and current and voltage waveforms are presented for documentation of the passively clamped converter. A passively clamped resonant DC-link converter with an oscillating link frequency of 65 kHz was realized in the laboratory, using insulated-gate bipolar transistors (IGBTs). The three-phase converter uses two current modulation methods, modified current regulated delta modulation (MCRΔM) and current regulated delta modulation (CRΔM). Both modulation methods are realized with analog electronics: MCRΔM uses an electrically programmable read-only memory (EPROM). MCRΔM is the most intelligent modulation method which restricts the changes of switch state in order to minimize the clamp energy