Power supply

Abstract

The invention discloses a power supply, which comprises a constant current power supply, wherein at least two current limiting protection branches are connected in parallel on an output loop of the constant current power supply; each of the current limiting protection branches comprises at least one load and a current limiting protector; the designed current limiting value of the current limiting protector of each branch is larger than the designed work current value of the current limiting protection branch where the current limiting protector is located; when the current of any branch in the current limiting protection branches is equal to or smaller than the designed work current of the branch, the current limiting protector in the branch works in a saturation conducting state; and when the current of any one in the current limiting protection branches is larger than the designed work current of the branch and reaches the designed current limiting value of the current limiting protector in the branch, the current limiting protector in the branch works in a current limiting state. Compared with the prior art, shorted faults can be effectively controlled, and when a shorted fault of the load does not occur, the current limiting protector works in a low power consumption state, which is beneficial to energy conservation and environment protection.

Description

technical field [0001] The invention relates to a power supply. Background technique [0002] At present, loads that need to be driven by a constant current usually work in series with multiple loads, and due to reliability and operating voltage, the number of loads in series cannot be too large, so in some high-power applications, it is generally used combination of series and parallel. [0003] figure 1 It is a kind of power supply in the prior art. As shown in the figure, it includes a constant current power supply, and multiple strings of load branches connected to the constant current power supply and connected in parallel with each other. The load is a load that needs to be driven by a constant current. Specifically, The load is LED, and the output current of the constant current power supply will be naturally distributed by these light strips during operation. However, when this series-parallel combination of LED lamps is working, if one of the loads has an LED sho...

AI Technical Summary

Problems solved by technology

However, when this series-parallel combination of LED lamps is working, if one of the loads has an LED short-circuit (short circuit is one of the most common failure forms of LEDs), the sum of the Vf of each LED in this branch is smaller than that of other circuits. , will lead to a substantial increase in the branch current, which often exceeds the maximum operating current of the LED, which can easily cause the LED to overheat and burn out

Images