Multi-circuit current-limiting power supplying circuit, controlling method thereof and current-limiting power supplying method thereof

Abstract

The invention discloses a multi-circuit current-limiting power supplying circuit, a controlling method of the multi-circuit current-limiting power supplying circuit and a current-limiting power supplying method of the multi-circuit current-limiting power supplying circuit. The power supplying circuit comprises an alternating-current power source, a rectifier, a current-limiting switch circuit and a load. The wave form of the alternating-current power source is equal to that of a sine wave alternating current. The alternating-current power source is connected with an input end of the rectifier, and the rectifier comprises two output ends. The current-limiting switch circuit comprises three ends, a first end of the current-limiting switch circuit is connected with a first output end of the rectifier, a second end of the current-limiting switch circuit is connected with a second output end of the rectifier and one end of the load, and the other end of the load is connected with a third end of the current-limiting switch circuit. The power supplying method comprises the steps that full-bridge rectifying is conducted on the alternating current, wherein the alternating current is the sine wave alternating current; the alternating current supplies power to the load directly and an energy storage capacitor supplies powder to the load; when an alternating current voltage is less than a phase range of an energy storage capacitor voltage, the alternating current stops supplying power and the energy storage capacitor supplies power to the load. The multi-circuit current-limiting power supplying circuit, the controlling method and the current-limiting power supplying method have the advantages that power factor is high, efficiency is high, output flash frequency is improved and circuit is simple.

Description

technical field [0001] The invention relates to the field of power supply circuits, in particular to a multi-loop current-limiting power supply circuit, a control method thereof, and a current-limiting power supply method, and is especially suitable for constant-current driving of LED lighting. technical background [0002] At present, LED lighting is being rapidly promoted for its energy saving, environmental protection and long life, and LED lamps have been widely used in lighting applications in various fields. The LED cannot be directly connected to the mains, and needs to be equipped with a corresponding constant current drive device. The current LED drive scheme is mainly based on the traditional high-frequency switching power supply. This scheme requires a high-frequency switching circuit, the circuit is complicated, and the cost is high, making many Manufacturers switch to linear constant current drive solutions. [0003] figure 1 In the process, the commercial pow...

AI Technical Summary

Problems solved by technology

Since the rectifier 202 is not directly connected with a large energy storage capacitor, the power factor of the circuit is improved, but the current on the LED light-emitting tube is intermittent, and its intermittent period is twice the frequency of the commercial power, which will cause human eye-perceivable light flicker, additionally, the same figure 1 The disadvantage of the circuit is the same. When the voltage drop of the LED light-emitting tube is small, the efficiency of the circuit is also very low.

[0005] image 3 exist figure 1 On the basis of the AC circuit, a capacitor 306 is connected in series in the AC circuit, and the rectified DC voltage is reduced by using the capacitive reactance of the capacitor 306, so that the efficiency can be improved when the LED voltage is low, but the introduction of the AC capacitive reactance makes the power of the power supply circuit factor is still low

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