Large-power intelligent dimming multiple-output power supply for suppressing electric surge with field-effect transistor

Abstract

The invention provides a large-power intelligent dimming multiple-output power supply for suppressing electric surge with a field-effect transistor. The power supply comprises an electric surge suppression unit, an LLC (Inductor-Inductor-Capacitor) resonance conversion unit, a synchronous rectification unit and more than one constant-current-output intelligent dimming unit, wherein a power resistor in the electric surge suppression unit is connected in parallel with the source electrode and the drain electrode of a field-effect transistor, and the loss of an electric surge suppression circuit is very low due to the extremely small on-resistance of the field-effect transistor so that the whole efficiency of the power supply is improved. The invention acquires the output efficiency up to 95 percent by the optimization design of parameters of an LLC resonance network, the constant-current-output intelligent dimming unit circuit of the invention increases the mean value of the output current by increasing the duty cycle of an output current when sensing infrared rays of a human body; and otherwise, the constant-current-output intelligent dimming unit circuit decreases the duty cycle of the output current but not decreases the peak value while no body passes by so as to ensure LED luminous power and prevent light from scattering over the ground.

Description

【Technical field】 [0001] The invention relates to a high-power LED driving power supply, in particular to a manufacturing method and a power supply device for driving a high-efficiency power supply similar to LED street lamps. 【Background technique】 [0002] In the prior art, in order to suppress the impact on devices such as rectifier diodes due to excessive surge current at the moment of power-on, the traditional method is to connect a high-power resistor in series in the main circuit. The inrush current method has its drawbacks: if a thermistor with a large resistance value is selected and the inrush current at startup is small, it can effectively protect the power supply. However, since the thermistor is connected in series in the main circuit, it will , the power loss is very large, which leads to a decrease in the overall efficiency of the power supply; if a thermistor with a small resistance value is selected, the circuit loss can be reduced, but the surge current at ...

AI Technical Summary

Problems solved by technology

[0002] In the prior art, in order to suppress the impact on devices such as rectifier diodes due to excessive surge current at the moment of power-on, the traditional method is to connect a high-power resistor in series in the main circuit. The inrush current method has its drawbacks: if a thermistor with a large resistance value is selected and the inrush current at startup is small, it can effectively protect the power supply. However, since the thermistor is connected in series in the main circuit, it will , the power loss is very large, which leads to a decrease in the overall efficiency of the power supply; if a thermistor with a small resistance value is selected, the circuit loss can be reduced, but the surge current at startup is large, and the power supply is increasingly damaged by repeated large surge current impacts. short power supply life

[0004] In the prior art LED drive power supply, when the power supply is lightly loaded, the efficiency drops

At present, the full-load efficiency of general high-power LED drive power is only about 85%, and the efficiency is even lower at light load, which does not meet the development needs of LED lighting

[0005] Furthermore, in the secondary rectification in the prior art, if a diode is used for rectification, the tube voltage drop of the diode is 0.7V, and the loss is relatively large

[0006] There is also a defect in the prior art: in practical applications, LED lighting lamps are required to have a dimming function

When linear dimming is used, the output current is constant and continuous. As the output current becomes smaller, the luminescence of the LED device is weakened, and the luminous efficiency is reduced, which will cause the problem that the light does not fall to the ground, that is, the instantaneous light intensity is insufficient and cannot be irradiated to the ground.

[0007] Especially when LED lamps are used in street lighting, it will have a serious impact on traffic safety

[0008] Moreover, in different lighting fields, the requirements for LED dimming are different, and linear dimming is no longer suitable for the needs of the situation.

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