Single-stage type LED drive power supply without electrolytic capacitor

Abstract

The invention discloses a single-stage type LED drive power supply without an electrolytic capacitor. The single-stage type LED drive power supply without the electrolytic capacitor is an AC / DC converter in essence, and the single-stage type LED drive power supply without the electrolytic capacitor is composed of an input filter rectification circuit, a fly-back primary switch circuit, an auxiliary winding full-bridge bidirectional circuit and a secondary rectification filter circuit. The single-stage type LED drive power supply without the electrolytic capacitor realizes the power factor correction through fixing the duty ratio of a main switch MOS tube Q1 and works in a current discontinuous mode to avoid the reverse recovery of a secondary diode QR; the main circuit thereof is a fly-back converter which is composed of the part 1, part 2 and part 4, an isolating transformer of the fly-back converter is provided with a winding, the auxiliary winding side uses a bidirectional power flow full-bridge converter to balance the instantaneous pulse difference between the input power and the output power, and the capacitance of an auxiliary energy storage capacitor is reduced through increasing the average voltage and voltage pulse of the auxiliary energy storage capacitor; the single-stage type LED drive power supply without the electrolytic capacitor removes double power frequency alternating current component of the output current, reduces the output filter capacitor capacitance and realizes the small volume and long service life, and the electrolytic capacitor can be substituted by a film capacitor; the output current of the LED drive power supply is constant current.

Description

Technical field: [0001] The invention relates to a single-stage non-electrolytic capacitor LED drive power supply, which belongs to the application field of switching power supplies, especially LED drive power supplies. Background technique: [0002] With the rapid development of human society, the demand for energy consumption is increasing rapidly, and the energy crisis is becoming more and more serious. There are two main ways to solve the energy crisis. One way is to develop renewable energy and reduce dependence on traditional fossil energy; the other way is to seek new energy-saving technologies to reduce energy consumption and improve energy utilization efficiency. Among them, lighting is an important aspect of human energy consumption. Traditional lighting products such as incandescent lamps, fluorescent lamps, and high-pressure sodium lamps have serious problems of high power consumption and low efficiency. Therefore, reducing the power required for lighting will h...

AI Technical Summary

Problems solved by technology

The life of electrolytic capacitors is generally only 5,000 hours, and the life of the LED body is 100,000 hours. The working life of the two is very different. Therefore, electrolytic capacitors are the key factors that limit the life of LED drive power supplies.

And the volume of the electrolytic capacitor is large, which affects the further improvement of the power density of the driving power supply

Images