LED lighting lamp anti-stroboscopic control circuit

Abstract

The utility model belongs to the technical field of lighting circuit, more specifically, it is a kind of LED lighting lamp anti-stroboscopic control circuit, including power supply, anti-stroboscopic circuit, drive circuit and LED group, anti-stroboscopic circuit, drive circuit and LED group are sequentially connected through contact point, power supply is converted into low voltage direct current by drive circuit to control drive LED light emitting;The anti-stroboscopic circuit includes the resistance R and the capacitor C connected in parallel, the capacitor R, the resistance C and the indicating lamp terminal post of LED power supply are connected in parallel respectively;The single-phase ac power supply voltage of LED lighting lamp anti-stroboscopic control circuit is 220V.The utility model LED lighting lamp anti-stroboscopic control circuit can control the ac induction leakage current on LED indicating lamp in 0~10muA range, solves the problem of non-normal lighting of LED indicating lamp due to induction leakage current.

Description

Technical Field

[0001] This utility model belongs to the technical field of lighting circuits, and more specifically, relates to an anti-flicker control circuit for LED lighting. Background Technology

[0002] LED lighting technology boasts advantages such as small size, high luminous efficacy, low power consumption, good stability, and high reliability, and is currently widely used in home lighting. With the popularization and widespread application of electronic devices, LED power indicator lights, as a common functional device, have become an indispensable part of people's lives and work.

[0003] Chinese patent document CN220776121U discloses a low-flicker LED driver circuit supporting dimming and color adjustment. A thyristor dimming circuit and a flicker removal circuit are connected via contacts. The flicker removal circuit is then connected to a color adjustment circuit via contacts. The AC input to the thyristor dimming circuit is converted into pulsed DC current by a bridge rectifier. A transformer establishes an electrodynamic circuit with positive voltage at the top and negative voltage at the bottom. After filtering by a polarized capacitor, the output voltage and current are established. A resistor and diode are used to control the output open-circuit voltage. Temperature compensation is achieved through diodes, and voltage changes on the dimming bus are detected by a resistor. However, in practical applications, LED indicator lights and their control circuits have distributed capacitance, especially in long-distance control circuits where the distributed capacitance is large. Under AC current, this can easily cause the LED power indicator light to illuminate due to AC induced leakage current even when no power is supplied.

[0004] The power indicator lights on the distribution cabinets, reactive power compensation cabinets, drawer cabinets, switch cabinets, distribution boxes, and pump control columns installed in the company's power distribution room have numerous circuits, which are laid and buried together with control lines, power cables, and other control and power cables. Due to the large number and length of cables, distributed capacitance exists between the cable cores and within the control lines. This distributed capacitance, in turn, causes AC induced leakage current under AC voltage, which in turn affects the internal circuit capacitance of the LED indicator lights. The AC induced leakage current at both ends of the LED power indicator lights in this factory's power distribution room often reaches 30-280uA, causing frequent false lighting of the control columns and power distribution room indicator lights. On-site inspection and disassembly revealed that all these falsely lit LED indicator lights used capacitors as control elements. When the equipment is stopped, both the running and stop lights are on, making it impossible for on-site operators to accurately judge the equipment's operating status, posing a significant safety hazard. Utility Model Content

[0005] This utility model aims to overcome at least one of the defects of the prior art and provides an LED lighting anti-flicker control circuit. The LED lighting anti-flicker control circuit of this invention can control the AC induced leakage current on the LED indicator within the range of 0 to 10 μA, solving the problem of the LED indicator not lighting normally due to induced leakage current. It is also simple to manufacture and easy to install, reducing the downtime of equipment due to operator misjudgment, with high safety and reliability and significant application effect.

[0006] The detailed technical solution of this utility model is as follows: An LED lighting anti-flicker control circuit includes a power supply, an anti-flicker circuit, a driver circuit, and an LED group. The anti-flicker circuit, the driver circuit, and the LED group are connected in sequence through contacts. The power supply converts AC power into low-voltage DC power through the driver circuit to control the LED to emit light. The anti-lightning circuit includes a resistor R and a capacitor C connected in parallel. The capacitor C and the resistor R are connected in parallel to the two ends of the LED power indicator terminal. When there is AC induced leakage current at the two ends of the LED power indicator terminal, the AC induced leakage current is bypassed through the capacitor and resistor, which greatly reduces the AC induced leakage current at the two ends of the LED power indicator, making it lower than the LED power indicator lighting current, and finally achieving the effect of turning off the LED power indicator.

[0007] Furthermore, the driving circuit includes a protection unit, a rectification unit, and a constant current filter unit, which are connected in sequence through contacts and finally connected to the LED light group; The protection unit includes a capacitor C3 and a resistor R1 connected in parallel. Capacitor C3 is connected in series to the AC mains power supply circuit optimized for anti-flashover, absorbing overvoltage during AC mains spikes and preventing voltage surges. Resistor R1 absorbs the energy of capacitor C3, preventing excessive discharge current. The protection circuit reduces the current and voltage of the AC mains, protecting subsequent circuits.

[0008] The rectifier unit is a bridge rectifier unit DB, which includes four diodes. During the positive and negative half-cycles of the AC mains power, the AC mains signal is rectified into a DC signal by the alternating conduction of diodes D1, D3 and D2, D4 respectively.

[0009] The constant current filter unit includes three constant current diodes CRD1, CRD2, and CRD3, and two capacitors C1 and C2. The constant current diodes are constant current devices with two ends. When working in the forward direction, there is a constant current region in which the current hardly changes with the voltage.

[0010] Furthermore, the resistance R of the anti-lightning circuit is selected as 220kΩ, and the resistance value can be increased or decreased according to the leakage current of the indicator light on site; the capacitance value of the anti-lightning circuit is selected as 4μF, and the capacitance value can be increased or decreased according to the leakage current of the indicator light on site; the voltage rating of the capacitor needs to be greater than the power supply voltage of the LED indicator light.

[0011] Furthermore, the power supply for the LED lighting anti-flicker control circuit is a single-phase AC power supply with a voltage of 220V.

[0012] The LED lighting anti-flicker control circuit shown in this utility model can control the AC induced leakage current on LED indicator lights within the range of 0-10μA, essentially solving the problem of all LED indicator lights lighting up abnormally due to induced leakage current. Furthermore, it is simple to manufacture and easy to install. It reduces equipment downtime caused by operator misjudgment, offers high safety and reliability, and has significant application effects.

[0013] Compared with the prior art, the beneficial effects of this utility model are as follows: This invention employs a method of connecting capacitor C and resistor R in parallel to the two ends of the LED power indicator terminal. When there is AC induced leakage current in the drive circuit, the AC induced leakage current is bypassed through the capacitor and resistor, which can reduce the value of AC induced leakage current to be lower than the starting current value of the LED power indicator. This solves the problem that the LED indicator lights up due to the large distributed capacitance caused by the long control line distance, even without power supply, and effectively avoids the occurrence of LED power indicator flickering faults. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of an LED lighting anti-flicker control circuit according to the present invention. Detailed Implementation

[0015] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0016] Example 1 However, in practical applications, LED indicator lights and their control circuits have distributed capacitance, especially in long-distance control circuits where the distributed capacitance is relatively large. Under AC power, this can easily cause the LED power indicator light to illuminate due to AC induced leakage current even when no power is supplied. When the equipment is stopped, both the running and stop lights will illuminate, making it impossible for on-site operators to accurately judge the equipment's operating status, posing a significant safety hazard. This embodiment provides an LED lighting anti-flicker control circuit that can control the AC induced leakage current on LED indicator lights within the range of 0-10μA, essentially solving the problem of all LED indicator lights illuminating abnormally due to induced leakage current. Furthermore, it is simple to manufacture and easy to install, reducing equipment downtime due to operator misjudgment, offering high safety and reliability, and demonstrating significant application effects.

[0017] The present invention adopts the following technical solution: As one implementation method, such as Figure 1 As shown, it includes a power supply, a lightning protection circuit, a driver circuit, and an LED group. The lightning protection circuit, the driver circuit, and the LED group are connected by contacts. The power supply converts AC power into low-voltage DC power through the driver circuit to control the LEDs to emit light. The anti-flash circuit includes a resistor R and a capacitor C connected in parallel. The capacitor C and the resistor R are connected in parallel to the two ends of the LED power indicator terminal. When there is AC induced leakage current at the two ends of the LED power indicator terminal, the AC induced leakage current is bypassed through the capacitor and resistor, which greatly reduces the AC induced leakage current at the two ends of the LED power indicator, making it lower than the LED power indicator lighting current, and finally achieving the effect of turning off the LED power indicator. In this embodiment, the indicator light can be dimly lit when the AC induced current is 50μA, and the indicator light is close to normal brightness when it is 300μA.

[0018] LEDs are characteristically sensitive semiconductor devices. Due to the nature of their light source, LEDs cannot be directly connected to a 220V AC mains power supply. They require a matching driver power supply. The driver circuit converts the AC power supply into a specific low-voltage DC power to control and drive the LED to emit light. Because of the LED's current-voltage and temperature characteristics, current LED lamp driver power supplies use a constant current source for startup. The constant current driver circuit outputs a constant current, while the output DC voltage varies within a certain range depending on the load resistance. A lower load resistance results in a lower output voltage, and a higher load resistance results in a higher output voltage. This constant output current ensures uniform LED brightness, long-term reliable light emission, and meets energy-saving requirements.

[0019] Preferably, the driving circuit includes a protection unit, a rectification unit, and a constant current filter unit, which are connected in sequence through contacts and finally connected to the LED light group; The protection unit includes a capacitor C3 and a resistor R1 connected in parallel. Capacitor C3 is connected in series with the AC mains power supply circuit to absorb overvoltage during AC mains spikes and prevent voltage surges. Resistor R1 absorbs the electrical energy of capacitor C3, preventing excessive discharge current. The protection circuit reduces the current and voltage of the AC mains power, thus protecting subsequent circuits.

[0020] The rectifier unit is a bridge rectifier unit DB; it consists of four diodes. During the positive and negative half-cycles of the AC mains power, the AC mains signal can be rectified into a DC signal by the alternating conduction of diodes D1, D3 and D2, D4 respectively.

[0021] The constant current filter unit includes three constant current diodes CRD1, CRD2, and CRD3, and two capacitors C1 and C2. The constant current diodes are two-terminal constant current devices; during forward operation, there is a constant current region where the current hardly changes with voltage variations. Using three constant current diodes as the main components for constant current, combined with capacitors C1 and C2, ensures that the front-end constant current diodes may not always operate in the constant current region due to voltage fluctuations. Therefore, the capacitors store charge, ensuring that when the front-end constant current diodes are not in the constant current region, the potential at the capacitors is higher, thus guaranteeing that the back-end constant current diodes always operate in the constant current region, resulting in a constant output current.

[0022] Three constant current diodes and two capacitors together form a filter circuit. Even if the power supply voltage is unstable or the load resistance changes greatly, the LED driver circuit can ensure that the output current is constant, so that the LED light emission is stable, the flicker frequency is reduced, and the life of the LED is also improved.

[0023] Preferably, the resistor R of the anti-lightning circuit is selected as 220kΩ, and the resistance value can be increased or decreased according to the leakage current of the indicator light on site; the capacitor value of the anti-lightning circuit is selected as 4μF, and the capacitor value can be increased or decreased according to the leakage current of the indicator light on site; the withstand voltage of the capacitor needs to be greater than the power supply voltage of the LED indicator light.

[0024] In this circuit, capacitor C mainly serves as a current shunt, which can effectively reduce the leakage current of the LED indicator and filter out spike pulse interference in the power supply. The parallel resistor R is used to discharge the capacitor. After being powered on, it forms a discharge circuit in the circuit to release the stored energy in the capacitor, prevent the voltage from increasing after the capacitor is charged, which would burn out the indicator light, and at the same time prevent the capacitor discharge from causing harm to the human body after the power is cut off.

[0025] This type of LED lighting anti-flicker control circuit can control the AC induced leakage current on LED indicator lights within the range of 0-10μA, essentially solving the problem of all LED indicator lights lighting up abnormally due to induced leakage current. Furthermore, it is simple to manufacture and easy to install. It reduces equipment downtime caused by operator misjudgment, offers high safety and reliability, and demonstrates significant application effects.

[0026] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A flicker-proof control circuit for LED lighting, characterized in that, It includes a power supply, a lightning protection circuit, a driver circuit, and an LED group. The lightning protection circuit, driver circuit, and LED group are connected in sequence through contacts. The power supply converts AC power into low-voltage DC power through the driver circuit to control the LED to emit light. The anti-lightning circuit includes a resistor R and a capacitor C connected in parallel, with capacitor R and resistor C connected in parallel to the two ends of the indicator terminal of the LED power supply.

2. The LED lighting anti-flicker control circuit according to claim 1, characterized in that, The driving circuit includes a protection unit, a rectification unit, and a constant current filter unit, which are connected in sequence through contacts and finally connected to the LED light group. The protection unit includes a capacitor C3 and a resistor R1 connected in parallel. The capacitor C3 is connected in series to the AC mains power supply circuit optimized by the anti-frequency lightning circuit, and the resistor R1 is used to absorb the electrical energy of the capacitor C3. The rectifier unit is a bridge rectifier unit DB, which includes four diodes. During the positive and negative half-cycles of the AC mains power, the AC mains signal is rectified into a DC signal by the alternating conduction of diodes D1, D3 and D2, D4 respectively. The constant current filter unit includes three constant current diodes CRD1, CRD2, and CRD3, and two capacitors C1 and C2.

3. The LED lighting anti-flicker control circuit according to claim 2, characterized in that, The resistor R of the anti-lightning circuit is selected to be 220kΩ; the capacitor value of the anti-lightning circuit is selected to be 4μF; the voltage rating of the capacitor is greater than the power supply voltage of the LED indicator.

4. The LED lighting anti-flicker control circuit according to claim 3, characterized in that, The power supply for the LED lighting anti-flicker control circuit is a single-phase AC power supply with a voltage of 220V.

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