DZK-type impedance converter is one translation unit in Electric unit combination of DDZ-Ⅲ. It includes voltage output and current output. Voltage output is used to reduce the output impedance in Ⅲ-model system; Current-output is used to expanse load capacity in Ⅲ-model system. In addition, the impedance converter also applies to the voltage / current or current / voltage conversing occasions.