Power converter

Abstract

The invention discloses a power converter. On the basis of an existing power converter circuit, a load characteristic match circuit is added, and meanwhile a dual voltage rectifying filter circuit and a constant-current output circuit are adopted. A current continuation circuit in the load characteristic match circuit enables an electronic transformer connected with the converter to maintain certain small current input when output of the electronic transformer is close to the lowest value. A current balance resistor in the load characteristic match circuit enables the electronic transformer to limit charging current in a filter capacitor in the dual voltage rectifying filter circuit when the electronic transformer outputs the alternating current peak value, and when the alternating current peak value outputted by the electronic transformer passes, certain charging current for the filter capacitor is maintained. By means of the load characteristic match circuit, the load characteristic of a light emitting diode (LED) lamp connected with the power converter is close to the load characteristic of the electronic transformer, and therefore the phenomena that LED spots are not lightened, flicker and are extremely low in brightness caused by the fact that the LED lamp is connected with the electronic transformer are avoided, and the power converter is applied to transformers of different types.

Description

technical field [0001] The invention belongs to the technical field of lighting appliances, and relates to a power converter and an LED lamp, in particular to a power converter for switching LED light sources. Background technique [0002] At present, the high-power power converters on the market use the low-voltage output of the electronic transformer of the halogen lamp cup to perform step-up rectification and filtering, and then drive it with a constant current to supply power to the high-power LED lamp group. The utility model with the patent number 201090000531.6 discloses a power converter and an LED lamp. The circuit includes an EMI filter circuit, a voltage doubler rectifier filter circuit and a constant current output circuit. When the halogen lamp cup electronic transformer outputs 6V to 12V AC When the current passes through the EMI filter circuit and the voltage doubler rectification filter circuit, a DC power with a voltage more than twice the input voltage is f...

AI Technical Summary

Problems solved by technology

Due to the mismatch between the power converter and the electronic transformer, that is, the load characteristics of the LED lamp are different from those of the electronic transformer, when this type of driver is used in conjunction with the existing electronic transformer, it will appear that the dot does not light up, flickers, and the brightness is extremely low. Phenomenon

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