Wide-voltage-range output current feed converter

Abstract

The invention provides a wide-voltage-range output current feed converter, which comprises a primary side power circuit, a first secondary side rectification circuit, a second secondary side rectification circuit and a change-over switch circuit, wherein the primary side power circuit is connected to the first secondary side rectification circuit and the second secondary side rectification circuitthrough a main power transformer; the first secondary side rectification circuit and the second secondary side rectification circuit are respectively connected with the change-over switch circuit; and the change-over switch circuit adjusts the output ends to be connected in series or in parallel by controlling the on-off state. According to the change-over switch circuit, the output ends are adjusted to be connected in series or in parallel by controlling the on-off state, high-voltage small current is output during series connection, low-voltage large current is output during parallel connection, the wide-voltage-range output requirement of the converter is further met, voltage and current stress of components such as a main power switch tube, a transformer and an alternating-current inductor in the circuit design is small, and therefore the power density and the efficiency of the power source can be effectively improved.

Description

technical field [0001] The present invention relates to a converter, in particular to a wide voltage range output current feeding converter. Background technique [0002] Wide voltage range output power requires that the output voltage of the converter can be continuously adjusted in a very wide range. At present, according to the different modulation methods, it can be roughly divided into a pulse width modulation (PWM) type topology and a frequency modulation type (PFM) type topology. PWM-type topology can realize wide-range voltage adjustment through the adjustment of duty cycle, such as traditional buck, boost, buck-boost and its derived isolation topologies. This type of topology generally outputs maximum power when outputting maximum voltage. When the output power supply with a wide voltage range requires this type of topology to output the maximum power at a small voltage, due to the large current, the duty cycle is extremely small, the current RMS value is large, th...

AI Technical Summary

Problems solved by technology

However, when the output voltage range is wide, the switching frequency adjustment range is extremely wide, especially at high frequencies, the switching loss, rectifier diode reverse recovery loss, driving loss, etc. increase sharply, seriously affecting the converter efficiency, so the PFM topology is not Suitable for occasions with a wide output voltage range

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