A radiation-resistant low-harmonic LED driving circuit and LED lamp

Abstract

The present invention provides a radiation-resistant low-harmonic LED driving circuit, comprising a rectifier unit and a driving unit. The input end of the rectifier unit is used to connect an external power supply, and the output end is connected to the driving unit, and is used to obtain a direct current power supply after rectifying and filtering the external power supply, and output it to the driving unit. The driving unit is used to convert the voltage of the direct current power supply into the working voltage of the LED light source. The driving unit comprises a first chip SM2315, a first capacitor, and a second resistor. The first pin of the first chip SM2315 is connected to the output end of the rectifier unit, the second pin and the ninth pin are grounded, the third pin is connected to the first capacitor and then to the ground, the fourth pin is connected to the second resistor and then to the ground, and the eighth pin, the seventh pin, the sixth pin and the fifth pin are used to connect the LED light source. Correspondingly, an LED lamp is also provided. The LED driving circuit can effectively withstand the radiation dose within the life of the lamp, and meet the life and power distribution requirements.

Description

Technical Field

[0001] The present invention relates to the field of lighting technology, and in particular to a radiation-resistant low-harmonic LED driving circuit and an LED lamp. Background Art

[0002] There are high-energy rays in the nuclear radiation contaminated areas of nuclear power plants. If the LED (Light-Emitting Diode) driving circuit uses a digital integrated circuit chip, the LED driving circuit will be damaged when the radiation reaches a certain dose, which will cause the lamp to malfunction.

[0003] At present, radiation-resistant driving circuits use heavy metals such as lead as shielding materials to protect the circuits from radiation damage. However, this method significantly increases the weight of the lamp. Some radiation-resistant lamps also need to be earthquake-resistant. The increase in the weight of the lamp poses a challenge to the earthquake-resistant identification and installation and fixation of the lamp. Alternatively, flexible lead-free radiation shielding materials can be used. However, the technical maturity of these new materials is low and the cost is high. Alternatively, the circuit and light source can be arranged separately. For example, the circuit and other parts with weak radiation resistance can be arranged in low-irradiation areas, but this arrangement method makes it difficult to install the lamp. Therefore, there is an urgent need for an LED driving circuit that can effectively withstand the radiation dose during the life of the lamp and meet the life and power distribution requirements. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a radiation-resistant low-harmonic LED drive circuit and an LED lamp in view of the above-mentioned deficiencies in the prior art, which can effectively withstand the radiation dose during the life of the lamp and meet the life and power distribution requirements.

[0005] The present invention provides a radiation-resistant low-harmonic LED driving circuit, comprising a rectifier unit and a driving unit. The input end of the rectifier unit is used to connect an external power supply, and the output end is connected to the input end of the driving unit, and is used to obtain a DC power supply after rectifying and filtering the external power supply, and output the DC power supply to the driving unit. The output end of the driving unit is used to connect an LED light source, and the driving unit is used to convert the voltage of the DC power supply into the working voltage of the LED light source 3.

[0006] The driving unit includes a first chip SM2315, a first capacitor C1, and a second resistor R2. The first pin of the first chip SM2315 is connected to the output end of the rectifier unit, the second pin and the ninth pin of the first chip SM2315 are grounded, the third pin of the first chip SM2315 is connected to the first capacitor C1 and then to the ground, the fourth pin of the first chip SM2315 is connected to the second resistor R2 and then to the ground, and the eighth pin, seventh pin, sixth pin and fifth pin of the first chip SM2315 are used to connect to the LED light source.

[0007] Preferably, the radiation-resistant low-harmonic LED driving circuit further comprises an adjusting unit for adjusting the output current value of the driving unit. The input end of the adjusting unit is connected to the output end of the rectifying unit, and the output end of the adjusting unit is connected to the first pin of the first chip SM2315.

[0008] Preferably, the regulating unit comprises a first resistor R1, one end of the first resistor R1 is connected to the output end of the rectifying unit, and the other end is connected to the first pin of the first chip SM2315.

[0009] Preferably, the LED driving circuit further comprises a protection unit, which is used to cut off the entire circuit when an internal overload or short circuit fault occurs in the LED driving circuit. The input end of the protection unit is used to connect to an external power supply, and the output end is connected to the rectifier unit.

[0010] Preferably, the protection unit adopts a chip fuse. The rectifier unit includes a diode rectifier bridge, a filter resistor R5 and a third capacitor C3, the input end of the diode rectifier bridge is connected to the output end of the protection unit, and the filter resistor R5 is connected in parallel with the third capacitor C3 and then connected in parallel with the output end of the diode rectifier bridge.

[0011] Preferably, the regulating unit further includes a third resistor R3, one end of the third resistor R3 is connected in parallel with one end of the first resistor R1 and then connected to the output end of the rectifying unit. The driving unit further includes a second chip SM2315, a first compensation resistor RJ1, a second compensation resistor RJ2, a third compensation resistor RJ3, a second capacitor C2, a fourth resistor R4, a fifth capacitor C5, a sixth capacitor C6, and a seventh capacitor C7. The first pin of the second chip SM2315 is connected to the other end of the third resistor R3, the second pin and the ninth pin of the second chip SM2315 are grounded, the third pin of the second chip SM2315 is connected to the second capacitor C2 and then grounded, the fourth pin of the second chip SM2315 is connected to the fourth resistor R4 and then grounded, the seventh pin, the sixth pin and the fifth pin of the second chip SM2315 are respectively connected in series with the third compensation resistor RJ3, the second compensation resistor RJ2 and the first compensation resistor RJ1, and then connected in parallel with the seventh pin, the sixth pin and the fifth pin of the second chip SM2315, and then connected in parallel with the fifth capacitor C5, the sixth capacitor C6, and the seventh capacitor C7, and then connected to the LED light source, the eighth pin of the first chip SM2315 and the eighth pin of the second chip SM2315 are connected in parallel to the LED light source.

[0012] Furthermore, the present invention also provides an LED lamp, comprising an LED light source, a substrate and the above-mentioned radiation-resistant low-harmonic LED driving circuit. The LED light source and the radiation-resistant low-harmonic LED driving circuit are arranged on the substrate, and the rectifier unit and the driving unit of the radiation-resistant low-harmonic LED driving circuit are respectively located at two ends of the LED light source.

[0013] Preferably, the substrate is made of ceramic.

[0014] Preferably, the LED light source includes four strings of LED lamp beads connected in series, and the eighth pin, the seventh pin, the sixth pin and the fifth pin of the first chip SM2315 are respectively connected to the four strings of LED lamp beads.

[0015] The radiation-resistant low-harmonic LED driving circuit and LED lamp of the present invention adopt a pure analog circuit to design the LED driving circuit, avoiding the use of components such as transformers and digital integrated chips that restrict the life of the lamp in a radiation environment, thereby improving the radiation resistance of the driving circuit and meeting the life requirements of the lamp. In particular, the linear constant current driving analog chip SM2315 is used to make the driving circuit have a lower harmonic distortion rate and meet the power distribution requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic structural diagram of a radiation-resistant low-harmonic LED driving circuit according to Embodiment 1 of the present invention;

[0017] Figure 2 This is a schematic diagram of the arrangement structure of the LED lamp according to Example 2 of the present invention. DETAILED DESCRIPTION

[0018] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0019] Embodiment 1:

[0020] like Figure 1 As shown, this embodiment provides a radiation-resistant low-harmonic LED driving circuit, and the LED driving circuit includes a rectifying unit 1 and a driving unit 4 .

[0021] The input end of the rectifier unit 1 is used to connect to an external power supply, and the output end is connected to the input end of the driver unit 4, and is used to obtain a DC power supply after rectifying and filtering the external power supply, and output the DC power supply to the driver unit 4. The output end of the driver unit 4 is used to connect to the LED light source 3, and the driver unit 4 is used to convert the voltage of the DC power supply into the working voltage of the LED light source 3. The driver unit 4 includes a first chip SM2315, a first capacitor C1, and a second resistor R2. The first pin of the first chip SM2315 is connected to the output end of the rectifier unit 1, the second pin and the ninth pin of the first chip SM2315 are grounded, the third pin of the first chip SM2315 is connected to the first capacitor C1 and then to the ground, the fourth pin of the first chip SM2315 is connected to the second resistor R2 and then to the ground, and the eighth pin, the seventh pin, the sixth pin and the fifth pin of the first chip SM2315 are used to connect to the LED light source 3.

[0022] In this embodiment, since the LED driving circuit of the prior art usually includes a transformer and a digital integrated chip, and the transformer and the digital integrated chip are easily damaged by radiation, thereby affecting the life of the lamp. Therefore, in this embodiment, a linear constant current driving analog chip SM2315 is used to convert the external power supply voltage (AC power supply voltage) into the working voltage of the LED light source. The chip SM2315 has a low total harmonic distortion rate and a high power factor. When the power required by the LED light source 3 is 15W, the driving unit 4 includes the first chip SM2315.

[0023] Optionally, the LED driving circuit further includes an adjusting unit 6 for adjusting the output current value of the driving unit 4. The input end of the adjusting unit 6 is connected to the output end of the rectifying unit 1, and the output end of the adjusting unit 6 is connected to the first pin of the first chip SM2315.

[0024] In this embodiment, the adjustment unit 6 includes a first resistor R1, one end of which is connected to the output end of the rectifier unit 1, and the other end is connected to the first pin of the first chip SM2315. The output current value of the driving unit 4 is adjusted by setting the first resistor R1 in the adjustment unit 6, thereby adjusting the brightness of the LED light source 3. For example, the resistance value of R1 in this embodiment is 4.7 kilo-ohms.

[0025] Optionally, the LED driving circuit further comprises a protection unit 5 for cutting off the entire circuit when an internal overload or short circuit occurs in the LED driving circuit. The input end of the protection unit 5 is used to connect to an external power supply, and the output end is connected to the rectifier unit 1.

[0026] Optionally, the protection unit 5 uses a 2410 chip fuse, which is connected to the AC power phase line L and the neutral line N. In this embodiment, the 2410 chip fuse is used to consider the radiation resistance requirements and economy of the drive circuit, as well as the production process. Therefore, the use of a chip fuse is more economical than a circuit breaker.

[0027] The rectifier unit 1 includes a diode rectifier bridge, a filter resistor R5 and a third capacitor C3. The input end of the diode rectifier bridge is connected to the output end of the protection unit 5. The filter resistor R5 is connected in parallel with the third capacitor C3 and then connected in parallel with the output end of the diode rectifier bridge.

[0028] In this embodiment, the AC input side AC / AC is connected to the protection unit 5 , and the DC output side V+ / V− is connected to the regulation unit 6 after filtering to supply power to the drive unit 4 .

[0029] Optionally, the regulating unit 6 further includes a third resistor R3, one end of the third resistor R3 is connected in parallel with one end of the first resistor R1 and then connected to the output end of the rectifying unit 1. The driving unit 4 further includes a second chip SM2315, a first compensation resistor RJ1, a second compensation resistor RJ2, a third compensation resistor RJ3, a second capacitor C2, a fourth resistor R4, a fifth capacitor C5, a sixth capacitor C6, and a seventh capacitor C7. The first pin of the second chip SM2315 is connected to the third resistor R3, the second pin and the ninth pin of the second chip SM2315 are grounded, the third pin of the second chip SM2315 is connected to the second capacitor C2 and then grounded, the fourth pin of the second chip SM2315 is connected to the fourth resistor R4 and then grounded, the seventh pin, the sixth pin and the fifth pin of the second chip SM2315 are respectively connected in series with the third compensation resistor RJ3, the second compensation resistor RJ2 and the first compensation resistor RJ1, and then connected in parallel with the seventh pin, the sixth pin and the fifth pin of the second chip SM2315, and then connected in parallel with the fifth capacitor C5, the sixth capacitor C6, and the seventh capacitor C7, and then connected to the LED light source 3, the eighth pin of the first chip SM2315 and the eighth pin of the second chip SM2315 are connected in parallel to the LED light source 3.

[0030] In this embodiment, since the power required by the LED light source 3 is 30W, two chips SM2315 are connected in parallel to provide a constant current power supply for the LED light source 3. Specifically, the first pin of the chip SM2315 is the DC power supply end of the chip. The first pin is connected to the rectifier unit 1 through the adjustment unit 6 (for example, R1=R3=4.7 kiloohms) to obtain a DC power supply. The second pin is the chip enable end, which is directly grounded to ensure that the chip SM2315 works as soon as it is powered on. The third pin is the chip compensation port, which ensures that the drive circuit has a lower total harmonic voltage and current distortion rate by connecting the first capacitor C1 and the second capacitor C2. The fourth pin is the output current setting port, which sets the rated output current value of the chip SM2315 by connecting the second resistor R2 and the fourth resistor R4 (for example, R2=R4=11 ohms). The fifth pin, the sixth pin, the seventh pin, and the eighth pin are constant current output ports. After the two chips SM2315 are connected in parallel, they provide constant current power for the LED light source 3 through the first compensation resistor RJ1, the second compensation resistor RJ2, the third compensation resistor RJ3 and the fifth capacitor C5, the sixth capacitor C6, and the seventh capacitor C7. For example, the resistance values ​​of the first compensation resistor RJ1, the second compensation resistor RJ2, and the third compensation resistor RJ3 are all set to 0 ohms for jumper use, and the capacitance values ​​of the fifth capacitor C5, the sixth capacitor C6, and the seventh capacitor C7 are all set to 104 farads for EMC (electromagnetic compatibility). The LED light source 3 includes four strings of LED lamp beads connected in series. When the voltage output of the driving unit 4 is greater than the voltage drop of the first string of LED lamp beads of the LED light source 3 (for example, the voltage of pin 8 is 120V), the first segment of LEDs lights up; when the voltage is greater than the sum of the first string of LEDs and the second string of LEDs of the LED light source 3 (for example, the voltage of pin 8 is 120V, and the voltage value of pin 7 is 180V), these two strings of lamp beads light up; and so on. When the voltage is greater than the sum of all the lamp beads of the LED light source 3, all the lamp beads are lit.

[0031] The radiation-resistant low-harmonic LED driving circuit of this embodiment adopts a pure analog circuit design to avoid using components such as transformers and digital integrated chips that restrict the life of lamps in radiation environments, thereby improving the radiation resistance of the driving circuit. In particular, the linear constant current driving analog chip SM2315 is used to make the driving circuit have a lower harmonic distortion rate and meet the power distribution requirements. The radiation-resistant low-harmonic LED driving circuit of this embodiment adopts a pure analog circuit design to avoid using components such as transformers and digital integrated chips that restrict the life of lamps in radiation environments, thereby improving the radiation resistance of the driving circuit. 60 The steady-state total dose test of Coγ-ray was carried out. The test results showed that the driver circuit can effectively withstand the radiation dose of 1.5x10 4Gy, according to the test of GB17625.1-2012 "Electromagnetic compatibility limit harmonic current emission limit (equipment current per phase ≤ 16A)", the total harmonic distortion rate of voltage and current of the circuit is less than 15%. Therefore, the radiation-resistant low-harmonic LED drive circuit of this embodiment can increase the service life of the lamp, reduce the replacement frequency of the lamp, and reduce the radiation dose received by the operation and maintenance personnel.

[0032] Embodiment 2:

[0033] like Figure 2 As shown, this embodiment provides an LED lamp, including an LED light source 3, a substrate 2 and the radiation-resistant low-harmonic LED driving circuit described in Embodiment 1.

[0034] The LED light source 3 and the radiation-resistant low-harmonic LED driving circuit are arranged on the substrate 2 , and the rectifying unit 1 and the driving unit 4 of the radiation-resistant low-harmonic LED driving circuit are respectively located at two ends of the LED light source 3 .

[0035] In this embodiment, the rectifier unit 1 and the drive unit 4 are respectively arranged at the two ends of the LED light source 3, so that the positional spatial separation of the drive unit 4 and the rectifier unit 1 can be achieved, thereby realizing the positional isolation of the strong current part and the weak current part in the circuit, preventing the strong current part circuit from interfering with the weak current circuit, thereby ensuring the stable operation of the drive circuit and improving the stability of the drive circuit.

[0036] Optionally, the substrate 2 is made of ceramic to meet the requirement that the lamp does not contain aluminum in a radiation environment.

[0037] Optionally, the LED light source 3 includes four strings of LED lamp beads connected in series, and the eighth pin, the seventh pin, the sixth pin and the fifth pin of the first chip SM2315 are respectively connected to the four strings of LED lamp beads.

[0038] It is to be understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, but the present invention is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A radiation-resistant low-harmonic LED driving circuit, used in nuclear radiation contaminated areas of nuclear power plants, characterized in that: The LED driving circuit comprises a rectifying unit 1 and a driving unit 4. The input end of the rectifier unit 1 is used to connect to an external power supply, and the output end is connected to the input end of the drive unit 4, and is used to obtain a DC power supply after rectifying and filtering the external power supply, and output the DC power supply to the drive unit 4. The output end of the driving unit 4 is used to connect to the LED light source 3. The driving unit 4 is used to convert the voltage of the DC power supply into the working voltage of the LED light source 3. The driving unit 4 includes a first chip SM2315, a first capacitor C1, and a second resistor R2. The first chip has a low total harmonic distortion rate and a high power factor. The first pin of the first chip SM2315 is connected to the output end of the rectifier unit 1, the second pin and the ninth pin of the first chip SM2315 are grounded, the third pin of the first chip SM2315 is connected to the first capacitor C1 and then grounded, the fourth pin of the first chip SM2315 is connected to the second resistor R2 and then grounded, and the eighth pin, seventh pin, sixth pin and fifth pin of the first chip SM2315 are used to connect the LED light source 3.

2. The radiation-resistant low-harmonic LED driving circuit according to claim 1, characterized in that: The LED driving circuit further includes an adjusting unit 6 for adjusting the output current value of the driving unit 4. The input end of the regulating unit 6 is connected to the output end of the rectifying unit 1 , and the output end of the regulating unit 6 is connected to the first pin of the first chip SM2315 .

3. The radiation-resistant low-harmonic LED driving circuit according to claim 2, characterized in that: The regulating unit 6 includes a first resistor R1 , one end of which is connected to the output end of the rectifying unit 1 , and the other end of which is connected to the first pin of the first chip SM2315 .

4. The radiation-resistant low-harmonic LED driving circuit according to claim 3, characterized in that: The LED driving circuit also includes a protection unit 5, which is used to cut off the entire circuit when an internal overload or short circuit occurs in the LED driving circuit. The input end of the protection unit 5 is used to connect to an external power supply, and the output end is connected to the rectification unit 1 .

5. The radiation-resistant low-harmonic LED driving circuit according to claim 4, characterized in that: Protection unit 5 uses a chip fuse. The rectifier unit 1 includes a diode rectifier bridge, a filter resistor R5 and a third capacitor C3. The input end of the diode rectifier bridge is connected to the output end of the protection unit 5. The filter resistor R5 is connected in parallel with the third capacitor C3 and then connected in parallel with the output end of the diode rectifier bridge.

6. The radiation-resistant low-harmonic LED driving circuit according to claim 5, characterized in that: The regulating unit 6 further includes a third resistor R3, one end of which is connected in parallel with one end of the first resistor R1 and then connected to the output end of the rectifying unit 1. The driving unit 4 further includes a second chip SM2315, a first compensation resistor RJ1, a second compensation resistor RJ2, a third compensation resistor RJ3, a second capacitor C2, a fourth resistor R4, a fifth capacitor C5, a sixth capacitor C6, and a seventh capacitor C7. The first pin of the second chip SM2315 is connected to the other end of the third resistor R3, the second pin and the ninth pin of the second chip SM2315 are grounded, the third pin of the second chip SM2315 is connected to the second capacitor C2 and then grounded, the fourth pin of the second chip SM2315 is connected to the fourth resistor R4 and then grounded, the seventh pin, the sixth pin and the fifth pin of the second chip SM2315 are respectively connected in series with the third compensation resistor RJ3, the second compensation resistor RJ2 and the first compensation resistor RJ1, and then connected in parallel with the seventh pin, the sixth pin and the fifth pin of the second chip SM2315, and then connected in parallel with the fifth capacitor C5, the sixth capacitor C6, and the seventh capacitor C7, and then connected to the LED light source 3, the eighth pin of the first chip SM2315 and the eighth pin of the second chip SM2315 are connected in parallel to the LED light source 3.

7. An LED lamp, characterized in that: It comprises an LED light source 3, a substrate 2 and a radiation-resistant low-harmonic LED driving circuit as claimed in any one of claims 1 to 6, The LED light source 3 and the radiation-resistant low-harmonic LED driving circuit are arranged on the substrate 2. The rectifier unit 1 and the driver unit 4 of the radiation-resistant low-harmonic LED driver circuit are respectively located at two ends of the LED light source 3 .

8. The LED lamp according to claim 7, characterized in that: The substrate 2 is made of ceramic.

9. The LED lamp according to claim 8, characterized in that: The LED light source 3 includes four strings of LED lamp beads connected in series. The eighth pin, the seventh pin, the sixth pin and the fifth pin of the first chip SM2315 are respectively connected to four strings of LED lamp beads.

Images