AC linear anti-surge high-voltage-resistant module

Abstract

According to the AC linear anti-surge high-voltage-resistant module, the stress of common-mode surge is improved by increasing the thickness of an insulating dielectric layer, and when the thickness of the insulating dielectric layer is 360 microns or above, the common-mode-surge-resistant stress can reach 4 KV or above. Therefore, when the module faces high common-mode surge voltage, the PCB is not prone to breakdown, and circuit faults caused by breakdown of the surge voltage are effectively avoided. The differential mode surge voltage is reduced step by step by adopting a four-stage protection circuit formed by the piezoresistors VR1-VR4 and the winding resistors RT1-RT4, so that the voltage finally reaching a rear-end circuit is in a safe range, the rear-end circuit is protected from being damaged by the high differential mode surge voltage, the differential mode surge stress resistance of the module is improved, and the differential mode surge stress resistance of the module is up to more than 6KV. According to the invention, the surge resistance and high-voltage stress resistance of the AC linear module are effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of intelligent lighting, and in particular to an AC linear surge and high-voltage resistant module. Background Art

[0002] Lightning surge (mainly simulating indirect lightning) refers to the interference voltage generated when a large amount of current flows into the external line or grounding resistance when lightning strikes the outdoor line. Another example is the voltage or current induced on the line by indirect lightning (such as lightning in clouds or clouds). Another example is when lightning strikes a nearby object and establishes an electromagnetic field around it, when the outdoor line passes through the electromagnetic field, voltage and current are induced on the line. Another example is when lightning strikes the nearby ground, the interference introduced by the ground current passing through the public grounding system.

[0003] In order to evaluate the tolerance of electronic equipment in a lightning environment, surge testing is one of the safety testing methods for AC linear modules. It is a process of testing the transient voltage and current of AC linear modules. The surge tolerance of AC linear modules is tested by simulating the voltage and current surge conditions that may be encountered in actual operation.

[0004] At present, the common mode surge stress resistance method of existing high-voltage modules is usually to arrange various lightning protection components between the live wire or neutral wire and the ground wire on the aluminum substrate to suppress the common mode surge. However, the surge stress resistance of this method is relatively limited, and generally can only withstand a surge voltage of about 2KV. If it exceeds this value, a breakdown phenomenon may occur, causing damage to the back-end circuit or load.

[0005] Therefore, there is an urgent need to provide an AC linear surge and high voltage resistant module to solve the above problems. Summary of the invention

[0006] The purpose of the present invention is to overcome the shortcomings and defects of the prior art and provide an AC linear surge and high-voltage resistant module to improve the common-mode surge stress resistance and differential-mode surge stress resistance of the AC linear module, so that the common-mode surge stress resistance reaches more than 4KV and the differential-mode surge stress resistance reaches more than 6KV.

[0007] The objective of the present invention is achieved through the following technical solutions:

[0008] An AC linear surge and high-voltage resistant module, which tests the surge stress of the module by simulating high-voltage surge impact through a lightning surge generator, characterized in that it comprises a PCB board and a varistor VR, the PCB board comprises a solder mask layer, a circuit layer, an insulating medium layer, and an aluminum material layer connected in sequence, the thickness of the insulating medium layer is greater than 360um, the live wire interface end L1 of the lightning surge generator is connected to the live wire interface end L of the solder mask layer, the zero wire interface end N1 of the lightning surge generator is connected to the zero wire interface end N of the solder mask layer, and the ground wire interface end G1 of the lightning surge generator is connected to the ground wire interface end G of the aluminum material layer;

[0009] At the same time, the live line interface terminal L1 of the lightning surge generator is connected to the first pin of the varistor VR, the second pin of the varistor VR is connected to the neutral line interface terminal N1 of the lightning surge generator, and the varistor VR is connected to the load.

[0010] As a preferred technical solution of the present invention, the module further comprises a fuse F1, the input end of the fuse F1 is connected to the live wire interface end L1 of the lightning surge generator, and the output end of the fuse F1 is connected to the first pin of the varistor VR1.

[0011] As a preferred technical solution of the present invention, a rectifier bridge circuit is further provided between the varistor VR and the load, the varistor VR is connected to the input end of the rectifier bridge circuit, and the output end of the rectifier bridge circuit is connected to the load.

[0012] As a preferred technical solution of the present invention, the module also includes a winding resistor RT1 and a winding resistor RT2, the first pin of the varistor VR is connected to the first pin of the winding resistor RT1, the second pin of the varistor VR is connected to the first pin of the winding resistor RT2, the second pins of the winding resistor RT1 and the winding resistor RT2 are respectively connected to the input end of the rectifier bridge circuit, and the output end of the rectifier bridge circuit is connected to the load.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] The present invention increases the stress of common-mode surge by increasing the thickness of the insulating dielectric layer. When the thickness of the insulating dielectric layer is above 360um, the stress of common-mode surge can reach above 4KV, so that when the AC linear module faces high common-mode surge voltage, the PCB board is not easily broken down, effectively avoiding circuit failure caused by surge voltage breakdown. By using varistors VR1-VR4 and winding resistors RT1-RT4 to form a four-level protection circuit to gradually reduce the differential-mode surge voltage, the voltage that finally reaches the back-end circuit is within a safe range, thereby protecting the back-end circuit from damage by high differential-mode surge voltage, and improving the differential-mode surge stress of the AC linear module, so that its differential-mode surge stress is as high as above 6KV. The present application effectively improves the surge resistance and high-voltage stress resistance of the AC linear module. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of common mode surge occurrence of the present invention.

[0016] Figure 2 It is a schematic diagram of the occurrence of differential mode surge of the present invention.

[0017] Figure 3 This is a test waveform diagram of an embodiment of the present invention. DETAILED DESCRIPTION

[0018] The present invention is further described in detail below in conjunction with embodiments and drawings, but the embodiments of the present invention are not limited thereto.

[0019] The specific implementation process of the present invention is as follows:

[0020] An AC linear surge and high-voltage resistant module, which simulates high-voltage surge impact through a lightning surge generator to test the surge stress of the module, includes a PCB board and a varistor VR, the PCB board includes a solder mask layer, a circuit layer, an insulating medium layer, and an aluminum layer connected in sequence, the thickness of the insulating medium layer is greater than 360um, the live wire interface terminal L1 of the lightning surge generator is connected to the live wire interface terminal L of the solder mask layer, the zero wire interface terminal N1 of the lightning surge generator is connected to the zero wire interface terminal N of the solder mask layer, and the ground wire interface terminal G1 of the lightning surge generator is connected to the ground wire interface terminal G of the aluminum layer. Further, in this embodiment, if Figure 1As shown, when a common-mode surge voltage with the same phase and direction occurs between the neutral line N1 and the ground line G1, the surge voltage will propagate from the solder mask layer L and diffuse through the circuit layer. By setting an insulating dielectric layer below the circuit layer, the surge voltage cannot penetrate the insulating dielectric layer and flow into the aluminum layer below due to the obstruction of the insulating dielectric layer, so that the surge voltage is limited between the circuit layer and the insulating dielectric layer. At the same time, the surge voltage from the ground line G1 diffuses through the aluminum layer and also cannot penetrate the insulating dielectric layer, so that the PCB board will not be broken down. When a common-mode surge voltage with the same phase and direction occurs between the live line L1 and the ground line G1, the common-mode surge voltage will propagate from the solder mask layer N and diffuse through the circuit layer. Also, due to the obstruction of the insulating dielectric layer, the common-mode surge voltage cannot penetrate the insulating dielectric layer and flow into the aluminum layer below, and the common-mode surge voltage is limited between the circuit layer and the insulating dielectric layer. The common-mode surge voltage from the ground line G1 diffuses through the aluminum layer and also cannot penetrate the insulating dielectric layer. By setting the thickness of the insulating dielectric layer to more than 360um, it is not easy to break through the PCB board even if the common-mode surge voltage peak is as high as 4KV, thereby improving the module's common-mode surge resistance and effectively avoiding circuit failures caused by surge voltage breakdown.

[0021] At the same time, the live line interface terminal L1 of the lightning surge generator is connected to the first pin of the varistor VR, the second pin of the varistor VR is connected to the neutral line interface terminal N1 of the lightning surge generator, and the varistor VR is connected to the load. When the lightning surge simultaneously generates differential mode surge voltages with the same phase and opposite direction between the live line L1 and the neutral line N1, the varistor will clamp the voltage to around the maximum limiting voltage of the varistor, and then flow to the back-end circuit to supply power to the load after suppressing the differential mode surge voltage through the varistor, ensuring that the voltage finally reaching the back-end circuit is within a safe range, thereby protecting the back-end circuit from damage by high differential mode surge voltage, and improving the module's tolerance to high differential mode surge stress, making its tolerance to differential mode surge stress as high as 6KV or more.

[0022] In an embodiment of the present invention, the module further includes a fuse F1, the input end of the fuse F1 is connected to the live wire interface end L1 of the lightning surge generator, and the output end of the fuse F1 is connected to the first pin of the varistor VR1. The fuse F1 is used to quickly fuse and cut off the circuit when a short circuit or a large current abnormality occurs in the back-end circuit, thereby protecting the back-end circuit and preventing the electronic device from spontaneous combustion.

[0023] In an embodiment of the present invention, a rectifier bridge circuit is further provided between the varistor VR and the load, the varistor VR is connected to the input end of the rectifier bridge circuit, and the output end of the rectifier bridge circuit is connected to the load. The rectifier bridge circuit is used to rectify the input alternating current into direct current output. Specifically, the alternating current suppressed by the varistor VR enters the rectifier bridge circuit through the input end, is rectified into pulsating direct current by the rectifier bridge circuit, and is output to the load for use. A varistor may also be provided after the rectifier bridge circuit as the last line of defense to ensure that the voltage is completely reduced to a safe range before being output to the load.

[0024] In an embodiment of the present invention, the module further includes a winding resistor RT1 and a winding resistor RT2, a first pin of the varistor VR is connected to a first pin of the winding resistor RT1, a second pin of the varistor VR is connected to a first pin of the winding resistor RT2, the second pins of the winding resistor RT1 and the winding resistor RT2 are respectively connected to the input end of the rectifier bridge circuit, and the output end of the rectifier bridge circuit is connected to the load. The winding resistor is used to absorb the residual voltage after the varistor is clamped. Specifically, when the differential mode surge voltage is too high, after being suppressed by the overvoltage clamping of the first-level varistor VR, the voltage still cannot be reduced to a safe range, then the winding resistor absorbs the remaining excessive voltage to the next-level surge circuit or other protection circuit for suppression and clamping until the voltage is reduced to a safe range, and then rectified by the rectifier circuit and supplied to the back-end circuit or load for use.

[0025] In this embodiment, in order to protect the module from damage caused by higher differential mode surge voltage, a multi-level protection circuit is provided to suppress the surge voltage step by step. In this embodiment, a four-level protection circuit is taken as an example. Figure 2As shown, when a lightning surge simultaneously generates a differential-mode surge voltage with the same phase and opposite direction between the live wire L1 and the neutral wire N1, the varistor VR will clamp the voltage to about the maximum limit voltage of the varistor VR. Specifically, when the lightning surge generator outputs a differential-mode surge voltage, the first-stage varistor will respond first, and the varistor VR1 will clamp the voltage to about its maximum limit voltage, which is much higher than the normal working voltage, but much lower than the voltage that may damage the circuit. The residual voltage after the voltage is clamped by the varistor VR1 is absorbed by the winding resistors RT1 and RT2 to the second stage. The second-stage varistor VR2 will further reduce the amplitude of the residual voltage, and the residual voltage after the varistor VR2 is processed is absorbed by the winding resistors RT3 and RT4 to the third stage. The third-stage varistor VR3 will further reduce the amplitude of the residual voltage. The residual voltage after the third-stage clamping is transmitted to the rectifier circuit DB1 for rectification and then clamped by the varistor VR4 for the final clamping. The voltage is reduced to a safe range and then transmitted to the load RL. After four levels of protection, the high differential mode surge voltage has been greatly reduced, and the back-end circuit or load can be safely powered. The protection circuit is composed of varistors VR1-VR4 and winding resistors RT1-RT4. The voltage of each level is lower than the previous level, which can gradually reduce the amplitude of the surge voltage and ensure that the voltage that finally reaches the back-end circuit is within a safe range.

[0026] By conducting an experimental test on the module of increasing the thickness of the insulating dielectric layer and setting the four-level protection circuit in this embodiment, the experimental waveform is as follows: Figure 3 As shown, the test steps are as follows:

[0027] Test Step 1

[0028] Test voltage: +6000V; Surge times: 5 / automatic; Surge interval: 60s; Trigger phase: Phase synchronization / cruise; Coupling path: L3->N; Output impedance: 2Ω

[0029] Test Step 2

[0030] Test voltage: -6000V; Surge times: 5 / automatic; Surge interval: 60s; Trigger phase: Phase synchronization / cruise; Coupling path: L3->N; Output impedance: 2Ω

[0031] Test Step 3

[0032] Test voltage: +4000V; Surge times: 5 / automatic; Surge interval: 60s; Trigger phase: Phase synchronization / cruise; Coupling path: L3->PE; Output impedance: 12Ω

[0033] Test Step 4

[0034] Test voltage: -4000V; Surge times: 5 / automatic; Surge interval: 60s; Trigger phase: Phase synchronization / cruise; Coupling path: L3->PE; Output impedance: 12Ω

[0035] Test Step 5

[0036] Test voltage: +4000V; Surge times: 5 / automatic; Surge interval: 60s; Trigger phase: Phase synchronization / cruise; Coupling path: N->PE; Output impedance: 12Ω;

[0037] Test Step 6

[0038] Test voltage: -4000V; Surge times: 5 / automatic; Surge interval: 60s; Trigger phase: Phase synchronization / cruise; Coupling path: N->PE; Output impedance: 12Ω;

[0039] The experimental results show that by increasing the thickness of the insulating dielectric layer to more than 360um, the common-mode surge withstand stress can reach more than 4KV; by setting up a four-level protection circuit, the module's differential-mode surge withstand stress can reach more than 6KV.

[0040] The present invention has the following beneficial effects:

[0041] 1. The circuit is simple and clear, without the need for additional differential mode protection components, effectively reducing the complexity and cost of the system;

[0042] 2. Low cost, no need for expensive discharge tubes, etc., only a few varistors and winding resistors are needed to achieve a differential mode protection effect of up to 6KV or more;

[0043] 3. All electronic components are common products on the market and are highly replaceable;

[0044] 4. The reference power switch mode is adopted to avoid the switching frequency problem, reduce the conducted and radiated interference, and no additional safety components are required, which reduces the cost and makes it easier to pass the certification.

[0045] 5. The common mode surge stress is increased by increasing the thickness of the insulating dielectric layer. When the insulating dielectric layer is above 360um, the common mode surge stress can reach more than 4KV;

[0046] 6. The use of high thermal conductivity aluminum-based material improves the thermal conductivity of the product and ensures the long life and reliability of the product.

[0047] The present application has broad application prospects and can be widely used in various lighting fixtures in technical fields such as intelligent lighting, healthy lighting, plant lighting, commercial lighting, outdoor lighting, and entertainment lighting, including but not limited to downlights, ceiling lamps, ceiling lamps, chandeliers, floor lamps for indoor use, as well as explosion-proof lamps and floodlights required for specific occasions, and fan lamps that combine lighting and practical functions.

[0048] The above-mentioned embodiments only express the implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be based on the attached claims.

Claims

1. An AC linear surge and high-voltage resistant module, which simulates high-voltage surge impact through a lightning surge generator to test the surge stress of the module, characterized in that: It comprises a PCB board and a varistor VR, wherein the PCB board comprises a solder resist layer, a circuit layer, an insulating dielectric layer, and an aluminum material layer connected in sequence, wherein the thickness of the insulating dielectric layer is greater than 360um, the live wire interface end L1 of the lightning surge generator is connected to the live wire interface end L of the solder resist layer, the zero wire interface end N1 of the lightning surge generator is connected to the zero wire interface end N of the solder resist layer, and the ground wire interface end G1 of the lightning surge generator is connected to the ground wire interface end G of the aluminum material layer; At the same time, the live line interface terminal L1 of the lightning surge generator is connected to the first pin of the varistor VR, the second pin of the varistor VR is connected to the neutral line interface terminal N1 of the lightning surge generator, and the varistor VR is connected to the load.

2. The AC linear surge and high voltage resistant module according to claim 1, characterized in that: The module further comprises a fuse F1, an input end of the fuse F1 is connected to a live wire interface end L1 of a lightning surge generator, and an output end of the fuse F1 is connected to a first pin of a varistor VR1.

3. The AC linear surge and high voltage resistant module according to claim 1, characterized in that: A rectifier bridge circuit is further provided between the varistor VR and the load. The varistor VR is connected to the input end of the rectifier bridge circuit, and the output end of the rectifier bridge circuit is connected to the load.

4. The AC linear surge and high voltage resistant module according to claim 3, characterized in that: The module also includes a winding resistor RT1 and a winding resistor RT2, a first pin of the varistor VR is connected to a first pin of the winding resistor RT1, a second pin of the varistor VR is connected to a first pin of the winding resistor RT2, second pins of the winding resistor RT1 and the winding resistor RT2 are respectively connected to an input end of a rectifier bridge circuit, and an output end of the rectifier bridge circuit is connected to a load.

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