Non-dimming LED power supply control system capable of slowly extinguishing in case of power failure

Abstract

The utility model provides a power-off slow-extinguishing non-dimming LED power supply control system, the control system is connected with an LED lamp group comprising a plurality of LED lamps which are connected in series to control the on-off of the LED lamp group, the control system comprises an energy maintaining unit, an on control unit and an off slow-extinguishing control unit, the energy maintaining unit comprises a working power supply and a control inductor, and the control inductor is connected with the on control unit. The positive electrode of the working power supply is connected with one end of the LED lamp set through the control inductor, the positive electrode of the working power supply is connected with the control end of the turn-on control unit, the turn-on control unit is further connected with the other end of the LED lamp set and the negative electrode of the working power supply, and the positive electrode of the working power supply is further connected with the control end of the turn-off slow-extinguishing control unit. And the turn-off slow-extinguishing control unit is also connected with the other end of the LED lamp group and the negative electrode of the working power supply at the same time. According to the utility model, after the working power supply is switched off, the LED lamp group is ensured to be extinguished slowly, and the probability of occurrence of safety accidents is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of LED lamp control, in particular to a non-dimming LED power supply control system with slow power-off. Background Art

[0002] In the existing power supply of LED lamps, most of them adopt the power supply mode that the power supply is directly connected in series with the LED lamp, and the power supply safety of the LED lamp is protected by setting a current limiting resistor. However, this power supply mode makes the LED lamp drive voltage discharge instantly through the circuit formed by the LED lamp and the current limiting resistor after the mains is disconnected, and the LED lamp will be extinguished instantly. This sudden change of brightness and darkness of the LED lamp may cause instant blindness and may cause safety accidents. Utility Model Content

[0003] The purpose of the utility model is to overcome the shortcomings of the prior art that LED lamps will go out instantly after power failure, causing instantaneous blindness and easily causing safety accidents, and provide a non-dimming LED power supply control system with slow-extinguishing function after power failure. By adding an on control unit and a off slow-extinguishing control unit, the on circuit and the off circuit of the LED lamp group are distinguished. When the LED lamp group needs to be turned off, the discharge of the controlled inductor can be used to make the LED lamp group go out slowly after the working power is disconnected, thereby avoiding the instantaneous extinguishing of the LED lamp group and reducing the probability of safety accidents.

[0004] The purpose of this utility model is achieved through the following technical solutions:

[0005] A non-dimming LED power supply control system with power-off slow-extinguishing is connected to an LED lamp group including a plurality of LED lamps connected in series to control the on and off of the LED lamp group. The control system comprises an energy maintenance unit, an on control unit and a off slow-extinguishing control unit. The energy maintenance unit comprises a working power supply and a control inductor. The positive electrode of the working power supply is connected to one end of the LED lamp group through the control inductor. The positive electrode of the working power supply is connected to the control end of the on control unit. The on control unit is also connected to the other end of the LED lamp group and the negative electrode of the working power supply. The positive electrode of the working power supply is also connected to the control end of the off slow-extinguishing control unit. The off slow-extinguishing control unit is also connected to the other end of the LED lamp group and the negative electrode of the working power supply. The on and off of the on control unit and the off slow-extinguishing control unit are controlled by the output voltage of the positive electrode of the working power supply.

[0006] Furthermore, the activation control unit includes a first switching element, the first end of the first switching element is the control end of the activation control unit, the first end of the first switching element is connected to the positive pole of the working power supply, the second end of the first switching element is connected to the other end of the LED light group, and the third end of the first switching element is connected to the negative pole of the working power supply.

[0007] Furthermore, the shutdown slow-down control unit includes a second switching element, the first end of the second switching element is the control end of the shutdown slow-down control unit, the first end of the second switching element is connected to the positive pole of the working power supply, the second end of the second switching element is connected to the other end of the LED light group, and the third end of the second switching element is connected to the negative pole of the working power supply.

[0008] Furthermore, the shutdown slow-down control unit also includes a control element, which includes a switching diode and a protection resistor, the positive electrode of the switching diode is connected to the first end of the second switching element, the negative electrode of the switching diode is connected to the second end of the second switching element, and the negative electrode of the switching diode is also connected to the other end of the LED lamp group through the protection resistor.

[0009] Furthermore, the first switch element is an NMOS tube, and the second switch element is a PMOS tube.

[0010] Furthermore, the output voltage of the positive electrode of the working power supply, the inductance value of the control inductor and the resistance value of the protection resistor are all adjustable.

[0011] Furthermore, a current limiting resistor is also connected to the positive electrode of the working power supply, one end of the current limiting resistor is connected to the positive electrode of the working power supply, and the other end of the current limiting resistor is respectively connected to the control end of the shutdown slow-extinguishing control unit and the control end of the opening control unit.

[0012] The beneficial effects of the utility model are:

[0013] On the basis of the working power supply, a control inductor is set, and the on circuit and the off circuit of the LED light group are further distinguished by adding an on control unit and a off slow-extinguishing control unit. When the LED light group needs to be turned on, it can be powered normally by the working power supply. When the LED light group needs to be turned off, the control inductor can be used to discharge in the absence of continuous voltage input. Therefore, after the working power supply is disconnected, the LED light group will not be extinguished instantly, but will be extinguished slowly, thereby reducing the probability of safety accidents. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural schematic diagram of the utility model;

[0015] Figure 2This is a schematic diagram of the overall circuit of a non-dimming LED power supply control system with slow power-off according to an embodiment of the utility model;

[0016] Figure 3 This is a circuit diagram of a discharge circuit when the LED lamp group is turned on in an embodiment of the utility model;

[0017] Figure 4 It is a circuit diagram of a discharge circuit when the LED lamp group is turned off according to an embodiment of the utility model.

[0018] Among them: 1. Energy maintenance unit, 11. Working power supply, 12. Control inductor, 2. Turn on control unit, 3. Turn off slow-extinguishing control unit, 4. LED light group. DETAILED DESCRIPTION

[0019] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0020] Example:

[0021] A non-dimming LED power supply control system is connected to an LED lamp group 4 including a plurality of LED lamps connected in series to control the on and off of the LED lamp group. Figure 1 As shown, it includes an energy maintenance unit 1, an opening control unit 2 and a shutdown slow-extinguishing control unit 3, the energy maintenance unit includes a working power supply 11 and a control inductor 12, the positive pole of the working power supply is connected to one end of the LED lamp group through the control inductor, the positive pole of the working power supply is connected to the control end of the opening control unit, the opening control unit is also connected to the other end of the LED lamp group and the negative pole of the working power supply, the positive pole of the working power supply is also connected to the control end of the shutdown slow-extinguishing control unit, the shutdown slow-extinguishing control unit is also connected to the other end of the LED lamp group and the negative pole of the working power supply, and the conduction and shutdown of the opening control unit and the shutdown slow-extinguishing control unit are controlled by the output voltage of the positive pole of the working power supply.

[0022] When the LED light group needs to be turned on, the output voltage of the positive pole of the working power supply is a high voltage. After the control end of the turning-on control unit receives the high voltage, the turning-on control unit will be turned on, and when the control end of the turning-off slow-extinguishing control unit receives the high voltage, the turning-off slow-extinguishing control unit will be turned off. At this time, the LED light group will be connected to the working power supply through the turning-on control unit to form a corresponding LED discharge circuit, and the working power supply continuously provides the working voltage for the LED light group.

[0023] When the LED light group is connected to the working power supply by turning on the control unit, the control inductor will also be connected to the corresponding LED discharge circuit for charging.

[0024] When the LED light group needs to be turned off, the working power supply will stop outputting voltage. At this time, the output voltage of the positive electrode of the working power supply is 0. According to the decrease in the output voltage of the positive electrode of the working power supply, the opening control unit is turned off, and the shutdown slow-off control unit will be turned on accordingly. At this time, the LED light group will be connected to the control inductor through the shutdown slow-off control unit to form a corresponding LED discharge circuit. At this time, the control inductor will discharge. Since the power of the control inductor is limited, this discharge process is the slow-off process of the LED lamp.

[0025] The activation control unit includes a first switching element, the first end of the first switching element is the control end of the activation control unit, the first end of the first switching element is connected to the positive pole of the working power supply, the second end of the first switching element is connected to the other end of the LED lamp group, and the third end of the first switching element is connected to the negative pole of the working power supply.

[0026] The shutdown slow-off control unit includes a second switch element, a first end of the second switch element is a control end of the shutdown slow-off control unit, a first end of the second switch element is connected to the positive pole of the working power supply, a second end of the second switch element is connected to the other end of the LED lamp group, and a third end of the second switch element is connected to the negative pole of the working power supply.

[0027] The first switch element is an NMOS tube, and the second switch element is a PMOS tube.

[0028] The shutdown slow-down control unit also includes a control element, which includes a switching diode and a protection resistor. The positive electrode of the switching diode is connected to the first end of the second switching element, the negative electrode of the switching diode is connected to the second end of the second switching element, and the negative electrode of the switching diode is also connected to the other end of the LED lamp group through the protection resistor.

[0029] The shutdown slow-off control unit can control the current flow direction through the control element, thereby realizing the control of the LED discharge circuit switching when the LED lamp group is turned off.

[0030] The output voltage of the positive electrode of the working power supply, the inductance value of the control inductor and the resistance value of the protection resistor are all adjustable.

[0031] The discharge formula of the control inductor is: Ip [ 1-e -t / τ ]=0;

[0032] Among them, I p It is the current during normal operation, which is related to the output voltage of the positive electrode of the working power supply and the resistance value in the loop, while τ=L / R, which is related to the inductance value of the control inductor and the resistance value connected to the loop. t is the discharge time of the control inductor, that is, the light-off time of the LED lamp group.

[0033] According to the discharge formula of the control inductor, the discharge time of the control inductor is only related to I p And τ, and because when the LED lamp group is turned off, the corresponding LED discharge circuit has a protective resistor connected to the shutdown slow-off control unit, so τ can be adjusted according to the resistance value of the protective resistor and the inductance value of the control inductor, and I p In addition to being related to the output voltage of the positive pole of the working power supply, it is also related to the resistance value in the circuit. Therefore, the output voltage of the positive pole of the power supply, the inductance value of the control inductor and the resistance value of the protection resistor are all set to be adjustable. The light-off time t of the LED lamp group can be controlled by adjusting the output voltage of the positive pole of the power supply, the inductance value of the control inductor and the resistance value of the protection resistor.

[0034] A current limiting resistor is also connected to the positive electrode of the working power supply, one end of the current limiting resistor is connected to the positive electrode of the working power supply, and the other end of the current limiting resistor is respectively connected to the control end of the shutdown slow-extinguishing control unit and the control end of the opening control unit.

[0035] Since both the opening control unit and the closing slow-extinguishing control unit realize the switching of the corresponding discharge circuit of the LED lamp group by adjusting the conduction and shutdown of the switching element, in order to ensure the safety of circuit operation, corresponding current limiting resistors are set at the control end of the closing slow-extinguishing control unit and the control end of the opening control unit.

[0036] In addition, the impedance of the shutdown slow-extinguishing control unit in this embodiment is greater than that of the startup control unit. After switching the discharge circuit of the LED lamp group, the output load can be reduced to achieve the effect of slow-extinguishing the LED lamp group.

[0037] The overall circuit diagram of the non-dimming LED power supply control system with slow power-off in this embodiment is as follows: Figure 2 As shown, the LED lamp group includes LED1, LED2, LED3 and a current limiting resistor R1 connected in series, the energy maintenance unit includes a working power supply EC1 and a control inductor L1, the opening control unit includes a MOS tube Q1 and a current limiting resistor R5, the shutdown slow-extinguishing control unit includes a MOS tube Q2, a protection resistor R2, a diode D1 and a current limiting resistor R4, and also includes a current limiting resistor R3 connected between the positive electrode of the working power supply and the control end of the shutdown slow-extinguishing control unit and the control end of the opening control unit.

[0038] When the LED light group needs to be turned on and the working power supply EC1 supplies power, the positive electrode LED+ of the working power supply EC1 provides sufficient voltage to the gate of the MOS tube Q1 from the resistor R3. The gate levels of the MOS tube Q1 and the gate levels of the MOS tube Q2 are both high, the MOS tube Q1 is turned on, and the MOS tube Q2 is turned off. At this time, the control inductor L1 is charged, and LED1, LED2, and LED3 are lit at the same time. At this time, the discharge circuit of the LED light group is the positive electrode LED+ of the working power supply EC1, the control inductor L1, the current limiting resistor R1, LED1, LED2, LED3, the MOS tube Q1, and the negative electrode LED- of the working power supply EC1. The circuit diagram is as follows: Figure 3 shown.

[0039] When the LED light group needs to be turned off, the working power supply EC1 is disconnected, and the voltage of the positive electrode LED+ of the working power supply EC1 is 0, that is, the gate levels of the MOS tube Q1 and the MOS tube Q2 are both low, the MOS tube Q1 is turned off, the MOS tube Q2 is turned on, and the discharge circuit of the LED light group is switched. The discharge circuit of the switched LED light group is the positive electrode LED+ of the working power supply EC1, the control inductor L1, the current limiting resistor R1, LED1, LED2, LED3, the protection resistor R2, the MOS tube Q2 and the negative electrode LED- of the working power supply EC1. The circuit diagram is as follows Figure 4 shown.

[0040] At this time, since there is no continuous voltage input to the control inductor L1, it is in a discharge state, and its discharge process is the process of the LED lamp group slowly turning off.

[0041] The above-described embodiment is only a preferred solution of the present invention and does not limit the present invention in any form. There are other variations and modifications without exceeding the technical solution described in the claims.

Claims

1. A non-dimming LED power supply control system with slow power-off, connected to an LED lamp group including a plurality of LED lamps connected in series, to control the on and off of the LED lamp group, characterized in that: It includes an energy maintenance unit, an opening control unit and a shutdown slow-extinguishing control unit. The energy maintenance unit includes a working power supply and a control inductor. The positive pole of the working power supply is connected to one end of the LED lamp group through the control inductor, the positive pole of the working power supply is connected to the control end of the opening control unit, the opening control unit is also connected to the other end of the LED lamp group and the negative pole of the working power supply, the positive pole of the working power supply is also connected to the control end of the shutdown slow-extinguishing control unit, the shutdown slow-extinguishing control unit is also connected to the other end of the LED lamp group and the negative pole of the working power supply, and the conduction and shutdown of the opening control unit and the shutdown slow-extinguishing control unit are controlled by the output voltage of the positive pole of the working power supply.

2. According to claim 1, a non-dimming LED power supply control system with slow power-off, characterized in that: The activation control unit includes a first switching element, the first end of the first switching element is the control end of the activation control unit, the first end of the first switching element is connected to the positive pole of the working power supply, the second end of the first switching element is connected to the other end of the LED lamp group, and the third end of the first switching element is connected to the negative pole of the working power supply.

3. A non-dimming LED power supply control system with slow power-off according to claim 2, characterized in that: The shutdown slow-off control unit includes a second switch element, a first end of the second switch element is a control end of the shutdown slow-off control unit, a first end of the second switch element is connected to the positive pole of the working power supply, a second end of the second switch element is connected to the other end of the LED lamp group, and a third end of the second switch element is connected to the negative pole of the working power supply.

4. A non-dimming LED power supply control system with slow power-off according to claim 3, characterized in that: The shutdown slow-down control unit also includes a control element, which includes a switching diode and a protection resistor. The positive electrode of the switching diode is connected to the first end of the second switching element, the negative electrode of the switching diode is connected to the second end of the second switching element, and the negative electrode of the switching diode is also connected to the other end of the LED lamp group through the protection resistor.

5. According to claim 3, a non-dimming LED power supply control system with slow power-off is characterized in that: The first switch element is an NMOS tube, and the second switch element is a PMOS tube.

6. A non-dimming LED power supply control system with slow power-off according to claim 4, characterized in that: The output voltage of the positive electrode of the working power supply, the inductance value of the control inductor and the resistance value of the protection resistor are all adjustable.

7. A non-dimming LED power supply control system with slow power-off according to claim 1, characterized in that: A current limiting resistor is also connected to the positive electrode of the working power supply, one end of the current limiting resistor is connected to the positive electrode of the working power supply, and the other end of the current limiting resistor is respectively connected to the control end of the shutdown slow-extinguishing control unit and the control end of the opening control unit.

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