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US 9,287,790 B2Granted
Electric power converter
AssigneePanasonic Intellectual Property Management Co., Ltd.
InventorsTakaaki Norisada, Keiji Akamatsu
Life of this patent
Estimating the term…
Abstract
An electric power converter includes a capacitor, a bridge circuit that includes a plurality of switching elements, a transformer, a secondary side rectifier circuit, a smoothing circuit, a detector that detects a value based on at least one of a capacitor voltage and a current flowing from the capacitor, and a control device that outputs a primary side drive signal to turns on/off each of the plurality of switching elements at a switching frequency, the control device increasing the switching frequency when the detected value increases, the control device reducing the switching frequency when the detected value decreases.
Claims20
An electric power converter, comprising:
- a capacitor that smooths a first rectified voltage to generate a capacitor voltage;
- a bridge circuit that converts the capacitor voltage to a primary side AC voltage, the bridge circuit including a plurality of switching elements;
- a current detection resistance disposed between the capacitor and the bridge circuit;
- a transformer that converts the primary side AC voltage to a secondary side AC voltage, the transformer including a primary winding connected to the bridge circuit and a secondary winding electromagnetically coupled to the primary winding;
- a secondary side rectifier circuit that rectifies the secondary side AC voltage to generate a second rectified voltage, the secondary side rectifier circuit being connected to the secondary winding;
- a smoothing circuit that smooths the second rectified voltage;
- a detector that detects a value based on at least a capacitor current which flows from the capacitor to the bridge circuit through the current detection resistance;
- and
- a controller that outputs a primary side drive signal to turn on/off each of the plurality of switching elements at a switching frequency, the controller increasing the switching frequency when the detected value increases, the controller reducing the switching frequency when the detected value decreases.
6 more elements
An electric power converter, comprising:
- a capacitor that smooths a first rectified voltage to generate a capacitor voltage;
- a bridge circuit that converts the capacitor voltage to a primary side AC voltage, the bridge circuit including a plurality of switching elements;
- a transformer that converts the primary side AC voltage to a secondary side AC voltage, the transformer including a primary winding connected to the bridge circuit and a secondary winding electromagnetically coupled to the primary winding;
- a secondary side rectifier circuit that rectifies the secondary side AC voltage to generate a second rectified voltage, the secondary side rectifier circuit being connected to the secondary winding;
- a smoothing circuit that smooths the second rectified voltage, the smoothing circuit including a secondary side capacitor and a coil which is disposed on a current path extending between the secondary side capacitor and the secondary side rectifier circuit;
- a secondary side switching circuit that turns on/off electrical conduction between the secondary winding and the smoothing circuit, the secondary side switching circuit including a plurality of secondary side switching elements;
- a detector that detects a value based on at least one of the capacitor voltage and a current flowing from the capacitor;
- an output detector that detects an output value based on at least one of an output voltage and an output current from the smoothing circuit;
- and
- a controller that
- determines a phase difference between the primary side drive signal and a secondary side drive signal on the basis of the output value,
- outputs the secondary side drive signal to turn on/off each of the plurality of secondary side switching elements with a phase in accordance with the phase difference, and
- outputs a primary side drive signal to turn on/off each of the plurality of switching elements at a switching frequency, wherein
- the controller increases the phase difference when the output value increases, and reduces the phase difference when the output value decreases, and
- the controller increases the switching frequency when the detected value increases, and reduces the switching frequency when the detected value decreases.
12 more elements
An electric power converter, comprising:
- a capacitor that smooths a first rectified voltage to generate a capacitor voltage;
- a full bridge circuit that converts the capacitor voltage to a primary side AC voltage, the full bridge circuit including
- a first switching element disposed on a current path extending between one end of the capacitor and one end of the primary winding,
- a second switching element disposed on a current path extending between the one end of the capacitor and another end of the primary winding,
- a third switching element disposed on a current path extending between another end of the capacitor and the one end of the primary winding, and
- a fourth switching element disposed on a current path extending between the other end of the capacitor and the other end of the primary winding;
- a transformer that converts the primary side AC voltage to a secondary side AC voltage, the transformer including a primary winding connected to the full bridge circuit and a secondary winding electromagnetically coupled to the primary winding;
- a secondary side rectifier circuit that rectifies the secondary side AC voltage to generate a second rectified voltage, the secondary side rectifier circuit being connected to the secondary winding;
- a smoothing circuit that smooths the second rectified voltage;
- a detector that detects a value based on at least one of the capacitor voltage and a current flowing from the capacitor;
- and
- a controller that outputs a primary side drive signal to
- turn on/off the first switching element at a switching frequency and a fixed duty ratio and with a first fixed phase,
- turn on/off the fourth switching element at the switching frequency and the fixed duty ratio and with a second fixed phase that is different from the first fixed phase,
- complementarily turn on/off the second switching element relative to the fourth switching element at the switching frequency, and
- complementarily turn on/off the third switching element relative to the first switching element at the switching frequency, wherein
- the controller increases the switching frequency when the detected value increases, and reduces the switching frequency when the detected value decreases.
14 more elements
Dependencies are inferred from the claim text.