Patent Application
20230151954
The present invention relates to a power adapter of an light-emitting diode (LED) light string, and move particularly to the power adapter of the LED light string having a valley-fill circuit.
A conventional power adapter of a holiday light string does not have an input voltage and a current synchronous valley fill circuit, thus having high work consumption. A power factor value is very low, for example, the power factor value is within 0.5 to 0.7, and the harmonic content is very high. Therefore, there is a great need for a high-efficiency, energy-saving, and low-cost LED power adapter for inventing valley-filling circuits.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages.
The primary objective of the present invention is to provide a power adapter of an LED light string having a valley-fill circuit which is capable of reducing the input loss, saving energy, and having a low cost.
To obtain above-mentioned objectives, a power adapter of an LED light string having a valley-fill circuit provided by the present invention contains: a casing and a plug fixed on a predetermined position of the casing.
The casing includes an energy-saving circuit board accommodated therein.
The casing further includes a connection portion which is electrically connected with a holiday light string, the energy-saving circuit board includes a wave filter, a rectifier, a valley fill circuit, and a transformer which are arranged from a voltage input end to a voltage output end of the energy-saving circuit board.
The valley fill circuit is defined between the rectifier and the wave filter so as to enhance a conduction angle of a rectifying tube and to change input currents from a spike to a waveform close to a sine wave, hence a power factor is close to above 0.7 to reduce a total harmonic distortion and an input loss, thus achieving energy saving.
The rectifier includes four diodes or a bridge rectifier circuit to rectify an alternating current (AC) voltage into a pulsating direct current (DC) voltage.
The transformer is comprised of at least one coil and a magnetic core so that when the electric currents pass through the at least one coil and change, an electromagnetic induction changes the AC voltage to generate a self-inductance voltage so as to block an increase or a decrease of the electric currents.
With reference to
The valley fill circuit 30 is defined between the rectifier 20 and the wave filter 10 so as to enhance a conduction angle of a rectifying tube and to change input currents from a spike to a waveform close to a sine wave, hence a power factor is close to above 0.7 to reduce a total harmonic distortion and an input loss, thus achieving energy saving.
The rectifier 20 includes four diodes or a bridge rectifier circuit to rectify an alternating current (AC) voltage into a pulsating direct current (DC) voltage, thus modulating the DC voltage via a switch efficiently.
Preferably, the transformer 40 is comprised of at least one coil and a magnetic core so that when the electric currents pass through the at least one coil and change, an electromagnetic induction changes the AC voltage to generate a self-inductance voltage so as to block an increase or a decrease of the electric currents.
Accordingly, the power adapter of the present invention has advantages as follows:
1) Reducing the input loss;
2) Saving energy; and
3) Having a low cost.
While the preferred embodiments of the invention have been set forth for the purpose of disclosure, modifications of the disclosed embodiments of the invention as well as other embodiments thereof may occur to those skilled in the art. Accordingly, the appended claims are intended to cover all embodiments which do not depart from the spirit and scope of the invention.
