Power conversion apparatus having an AC/DC converter which outputs to a DC/DC converter which is controlled by a controller

摘要

A power conversion apparatus includes a high-power-factor converter section converting an AC voltage to a DC voltage, a smoothing capacitor, a DC/DC converter section, and a control circuit. The control circuit controls the high-power-factor converter section such that the power factor of AC is controlled and a DC voltage follows a target value, and performs duty control for semiconductor switching devices such that a DC voltage from the DC/DC converter section to a load follows an instruction value. In accordance with the DC voltage, the control circuit adjusts the DC voltage target value of the high-power-factor converter section such that the duty ratio of the semiconductor switching devices approaches a set value, thereby optimizing the duty ratio of the semiconductor switching devices and reducing power loss.

主权项

1. A power conversion apparatus comprising:
an AC/DC converter which converts an AC voltage to a DC voltage; a smoothing capacitor connected to the DC side of the AC/DC converter; a DC/DC converter, comprising a semiconductor switch, which performs DC/DC conversion for DC power of the smoothing capacitor and outputs the resultant power to a load; and a controller which controls the AC/DC converter such that a power factor of AC is controlled and the DC voltage of the AC/DC converter follows a DC voltage target value, and which controls the DC/DC converter by controlling a duty ratio of the semiconductor switch such that a DC input/output between the DC/DC converter and the load follows an instruction value, wherein the controller adjusts the DC voltage target value of the AC/DC converter such that the duty ratio of the semiconductor switch of the DC/DC converter approaches a set value.