Primary-side controlled driving switch power supply and outdoor LED lamp

Abstract

The application relates to a primary side controlled driving switching power supply and an outdoor LED lamp, wherein the driving switching power supply comprises an input connection end, a filter rectifier circuit, a control circuit, a transformer T2 and a power supply output circuit; the input connection end is connected with the filter rectifier circuit, is connected into an AC power supply as an AC input circuit and outputs a first DC power supply; the transformer T2 is controlled by the control circuit to convert the first DC power supply into a second DC power supply, which is output to a load through the power supply output circuit; the driving switching power supply further comprises a lightning protection circuit arranged in the AC input circuit to release a high-voltage power supply input into the AC input circuit to the shell ground, a peak value absorption circuit connected with a power supply output end of the filter rectifier circuit to absorb lightning peak values encountered by the AC input circuit and to perform filtering treatment on the first DC power supply; the driving power supply can be prevented from being damaged by high-energy voltage such as lightning and can resist voltage peak influence, so that the circuit is effectively protected and the circuit safety is improved.

Description

Technical Field

[0001] This invention relates to LED driver power supplies, and more particularly to a primary-side controlled driver switching power supply and an outdoor LED lighting fixture. Background Technology

[0002] LED lights are gradually replacing traditional lighting sources and are being used more and more widely in various lighting fields. With the rapid development of social and economic construction, the level of urban road lighting infrastructure has become an important indicator of the speed and quality of urban development. The quality of lighting projects not only affects the safety of vehicles and pedestrians but also relates to whether energy conservation and environmental protection goals can be achieved. Currently, energy consumption in my country's road lighting is very serious, with major problems including excessive lighting system design, outdated lighting control methods, flawed energy-saving concepts, and simplistic energy-saving measures. More importantly, there are issues with faulty protection mechanisms.

[0003] Everyone knows that outdoor lighting needs to function properly regardless of the weather, especially in remote areas. Harsh environments and fluctuations in grid voltage can cause unstable power output to LED lights, leading to malfunctions. For example, thunderstorms can easily damage LED lights and their drivers. Ultimately, this will result in customer complaints and resentment, ranging from returns and lost customers to severe financial losses that can cripple the business and even lead to bankruptcy. Finally, it will require significant investment of manpower, resources, and money for repairs and modifications. Summary of the Invention

[0004] In view of the above-mentioned defects in the prior art, the present invention aims to solve the technical problem that existing drive switching power supplies are easily affected by harsh environments and fluctuations in grid voltage.

[0005] The technical solution adopted by the present invention to solve its technical problem is: to construct a primary-side controlled drive switching power supply, including an input connection terminal, a filter and rectifier circuit, a control circuit, a transformer T2, and a power output circuit that can be connected to a load;

[0006] The input connection terminal is connected to the filter and rectifier circuit, serving as an AC input circuit to access AC power and outputting a first DC power supply after filtering and rectification. The first path of the power output terminal of the filter and rectifier circuit is connected to the control circuit, and the second path is connected to the transformer T2. The transformer T2 is connected to both the control circuit and the power output circuit. The control circuit controls the transformer T2 to convert the first DC power supply into a second DC power supply, which is then output to the load via the power output circuit.

[0007] The driving switching power supply also includes a lightning protection circuit and a peak absorption circuit; the lightning protection circuit is located in the AC input circuit; the peak absorption circuit is connected to the power output terminal of the filter rectifier circuit and is used to absorb lightning spikes encountered by the AC input circuit and to filter the first DC power supply output.

[0008] Preferably, the input connection terminal includes a live wire input terminal ACL for connecting the live wire, a neutral wire input terminal ACN for connecting the neutral wire, and a ground wire input terminal PG1 for connecting the ground wire.

[0009] Preferably, the peak absorption circuit includes a fifth diode D5, a twenty-seventh resistor R27 and a twenty-eighth resistor R28 for surge protection, and a third electrolytic capacitor CE3;

[0010] The anode of the fifth diode D5 is connected to the power output terminal of the filter rectifier circuit, the cathode of the fifth diode D5 is connected to the positive terminal of the third electrolytic capacitor CE3, and the negative terminal of the third electrolytic capacitor CE3 is connected to the first ground terminal; the first terminal of the twenty-seventh resistor R27 is connected to the anode of the fifth diode D5, and the second terminal of the twenty-seventh resistor R27 is connected to the cathode of the fifth diode D5 via the twenty-eighth resistor R28.

[0011] Preferably, the lightning protection circuit includes a first lightning protection unit; the first lightning protection unit is disposed between the input connection terminal and the filter rectifier circuit, and is connected to both the input connection terminal and the filter rectifier circuit respectively, so as to release the high voltage power supply of the AC input circuit to the chassis ground;

[0012] The first lightning protection unit includes a first varistor MOV1, a second varistor MOV2, and a second discharge tube FDG2; the two ends of the first varistor MOV1 are respectively connected to the live wire input terminal ACL and the neutral wire input terminal ACN; the first end of the second varistor MOV2 is connected to the neutral wire input terminal ACN, and the second end of the second varistor MOV2 is connected to the chassis ground through the second discharge tube FDG2.

[0013] Preferably, the filter and rectifier circuit includes a first EMC unit, a rectifier unit, and a second EMC unit; the first terminal of the first EMC unit is connected to the input terminal, the second terminal of the first EMC unit is connected to the rectifier unit and then to the first terminal of the second EMC unit, and the second terminal of the second EMC unit is connected to the control circuit on one side and to the transformer T2 on the other side.

[0014] Preferably, the first EMC unit includes a first common-mode inductor LF1, a first capacitor CY1, a second capacitor CY2, a third capacitor CX1, a first discharge tube FDG1, and a second common-mode inductor LF2;

[0015] The first input terminal of the first common-mode inductor LF1 is connected to the live wire input terminal ACL, the second input terminal of the first common-mode inductor LF1 is connected to the neutral wire input terminal ACN, the first output terminal of the first common-mode inductor LF1 is connected to the first terminal of the second capacitor CY2, the first terminal of the third capacitor CX1, and the first input terminal of the second common-mode inductor LF2; the second terminal of the third capacitor CX1 and the second input terminal of the second common-mode inductor LF2 are connected to the second output terminal of the first common-mode inductor LF1, and the second output terminal of the first common-mode inductor LF1 is connected to the chassis ground through the first capacitor CY1; the ground input terminal PG1 and the second terminal of the second capacitor CY2 are connected to the chassis ground; the first output terminal and the second output terminal of the second common-mode inductor LF2 are respectively connected to the rectifier unit; the two ends of the first discharge tube FDG1 are respectively connected to the first input terminal and the first output terminal of the second common-mode inductor LF2.

[0016] Preferably, the lightning protection circuit further includes a second lightning protection unit; the second lightning protection unit is disposed in the filter rectifier circuit and connected between the first EMC unit and the bridge rectifier BD1, so as to clamp the voltage at both ends of the AC input of the bridge rectifier BD1 when encountering high voltage input;

[0017] The second lightning protection unit includes a first TVS diode TSS1 and a third varistor MOV3; the first end of the first TVS diode TSS1 is connected to the first EMC unit, the second end of the first TVS diode TSS1 is connected to the first end of the third varistor MOV3, and the second end of the third varistor MOV3 is connected to the second output terminal of the second common mode inductor LF2.

[0018] Preferably, the control circuit includes a first controller U1, a plurality of first voltage dividing resistors for voltage division, a plurality of first filter capacitors for filtering, a first MOSFET Q1, an adjustable resistor circuit, and a voltage output adjustment circuit.

[0019] The power output terminal of the filter rectifier circuit has one path connected to the sixth pin of the first controller U1 for power supply through a portion of the first voltage divider resistor, and another path connected to the first pin of the first controller U1 for current compensation control through two portions of the first voltage divider resistor and a portion of the first filter capacitor. The fifth pin of the first controller U1 for outputting pulse signals is connected to the gate of the first MOSFET Q1, and the drain of the first MOSFET Q1 is connected to the transformer T2. The adjustable resistor circuit is connected to the third pin of the first controller U1 for current detection, and the output current of the transformer T2 can be adjusted by adjusting the resistance value of the adjustable resistor circuit. The voltage output adjustment circuit is connected to the eighth pin of the first controller U1 as a PWM dimming input, and is used to adjust the second DC power supply output by the transformer T2.

[0020] Preferably, the first controller U1 is a control chip with the model number SY5882AFAC.

[0021] The present invention also constructs an outdoor LED lamp, including a light source module and a driving power supply device connected to the light source module; the driving power supply device includes the aforementioned primary-side controlled driving switching power supply.

[0022] The implementation of this invention has the following beneficial effects: the primary-side controlled drive switching power supply constructed in this invention can improve the lightning protection level, prevent high-energy voltages such as lightning from damaging the drive power supply, resist the impact of voltage spikes, effectively protect the circuit, improve the safety of the circuit, and can be applied to outdoor drive power supplies. Attached Figure Description

[0023] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings:

[0024] Figure 1 This is a circuit schematic diagram of the primary-side control section of the drive switching power supply of the present invention.

[0025] Figure 2 This is a circuit diagram of the secondary output section of the primary-side controlled drive switching power supply of the present invention. Detailed Implementation

[0026] To provide a clearer understanding of the technical features, objectives, and effects of this invention, specific embodiments are now described in detail with reference to the accompanying drawings. In the following description, it should be understood that the orientations or positional relationships indicated by terms such as "front," "rear," "upper," "lower," "left," "right," "longitudinal," "horizontal," "vertical," "horizontal," "top," "bottom," "inner," "outer," "head," and "tail" are based on the orientations or positional relationships shown in the accompanying drawings, and are constructed and operated in a specific orientation. They are only for the convenience of describing this technical solution and do not indicate that the device or element referred to must have a specific orientation; therefore, they should not be construed as limitations on this invention.

[0027] It should also be noted that, unless otherwise explicitly specified and limited, terms such as "installation," "connection," "linking," "fixing," and "setting" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. When an component is referred to as being "on" or "below" another component, the component can be located "directly" or "indirectly" on the other component, or there may be one or more intermediary components. The terms "first," "second," "third," etc., are only for the convenience of describing this technical solution and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, features defined with "first," "second," "third," etc., may explicitly or implicitly include one or more of that feature. For those skilled in the art, the specific meaning of the above terms in this invention can be understood according to the specific circumstances.

[0028] Figure 1 , Figure 2 The circuit schematic of the primary-side controlled drive switching power supply provided in the first embodiment of this application is shown. For ease of explanation, only the parts relevant to this embodiment are shown, specifically:

[0029] A primary-side controlled drive switching power supply includes an input connection terminal 1, a protection circuit, a filter and rectifier circuit 2, a control circuit 4, a transformer T2, and a power output circuit 5.

[0030] Input terminal 1 is connected in sequence to a protection circuit and a filter / rectifier circuit 2, serving as an AC input circuit. Input terminal 1 is used to connect to an AC power source. The protection circuit provides overload protection. The filter / rectifier circuit 2 is used to filter and rectify the connected AC power source and output a first DC power source. The first output of the filter / rectifier circuit 2 is connected to the control circuit 4, and the second output is connected to the transformer T2. The transformer T2 is connected to the control circuit 4 and the power output circuit 5. The power output circuit 5 is used to connect to the load. Specifically, the control circuit 4 controls the transformer T2 to convert the first DC power source into a second DC power source, which is then output to the load via the power output circuit 5.

[0031] The driving switching power supply also includes a lightning protection circuit and a peak absorption circuit 33; the lightning protection circuit is located in the AC input circuit; the peak absorption circuit 33 is connected to the power output terminal of the filter rectifier circuit, and is used to absorb lightning spikes encountered by the AC input circuit and to filter the first DC power supply output.

[0032] Furthermore, the input connection terminal 1 includes a live wire input terminal ACL for connecting the live wire, a neutral wire input terminal ACN for connecting the neutral wire, and a ground wire input terminal PG1 for connecting the ground wire;

[0033] Furthermore, the protection circuit can be a fuse F1, which will melt and cut off the current when the current abnormally rises to a certain level and temperature, thus protecting the safe operation of the circuit. Specifically, the first end of the fuse F1 is connected to the live wire input terminal ACL, and the second end of the fuse F1 is connected to the filter rectifier circuit 2, specifically connected to the first common mode inductor LF1 in the filter rectifier circuit 2.

[0034] Furthermore, the filter rectifier circuit 2 includes a first EMC unit 21, a rectifier unit 22, and a second EMC unit 23; the first end of the first EMC unit 21 is connected to the input connection terminal 1, the second end of the first EMC unit 21 is connected to the rectifier unit 22 and then to the first end of the second EMC unit 23, and the second end of the second EMC unit 23 is connected to the control circuit 4 on one side and to the transformer T2 on the other side.

[0035] Furthermore, the first EMC unit 21 includes a first common-mode inductor LF1, a first capacitor CY1, a second capacitor CY2, a third capacitor CX1, a first discharge transistor FDG1, and a second common-mode inductor LF2. Specifically, the first input terminal of the first common-mode inductor LF1 is connected to the live wire input terminal ACL, the second input terminal of the first common-mode inductor LF1 is connected to the neutral wire input terminal ACN, and the first output terminal of the first common-mode inductor LF1 is connected to the first terminal of the second capacitor CY2, the first terminal of the third capacitor CX1, and the first input terminal of the second common-mode inductor LF2; the third capacitor CY1... The second terminal of X1 and the second input terminal of the second common-mode inductor LF2 are connected to the second output terminal of the first common-mode inductor LF1, and the second output terminal of the first common-mode inductor LF1 is connected to the chassis ground through the first capacitor CY1; the ground input terminal PG1 and the second terminal of the second capacitor CY2 are connected to the chassis ground; the first output terminal and the second output terminal of the second common-mode inductor LF2 are respectively connected to the rectifier unit 22, specifically the two AC input terminals of the bridge rectifier BD1; the two ends of the first discharge tube FDG1 are respectively connected to the first input terminal and the first output terminal of the second common-mode inductor LF2.

[0036] The rectifier unit 22 can be a bridge rectifier BD1; specifically, the first end of the bridge rectifier BD1 is connected to the first EMC unit 21, and the second end is connected to the second EMC unit 23.

[0037] The second EMC unit 23 includes a first differential mode inductor L1, a fourth capacitor CB1, and a fifth capacitor CB2. Specifically, the first terminal of the first differential mode inductor L1 is connected to the first terminal of the fourth capacitor CB1 and the positive output terminal of the rectifier unit 22, and the second terminal of the first differential mode inductor L1 is connected to the first terminal of the fifth capacitor CB2. The second terminals of the fourth capacitor CB1 and the fifth capacitor CB2 are connected to the first ground terminal.

[0038] Understandably, the electromagnetic interference suppression capabilities of common-mode and differential-mode inductors, along with the filtering capabilities of capacitors, enable switching power supplies to pass EMC tests.

[0039] Furthermore, the surge protection circuit includes a first surge protection unit 31, which is located between the input connection terminal 1 and the filter rectifier circuit 2, and is connected to both the input connection terminal 1 and the filter rectifier circuit 2 to release the high-voltage power supply entering the AC input circuit to the chassis ground. Specifically, the first surge protection unit 31 includes a first varistor MOV1, a second varistor MOV2, and a second discharge tube FDG2. The two ends of the first varistor MOV1 are connected to the live wire input terminal ACL and the neutral wire input terminal ACN, respectively. The first end of the second varistor MOV2 is connected to the neutral wire input terminal ACN, and the second end of the second varistor MOV2 is connected to the chassis ground through the second discharge tube FDG2.

[0040] Understandably, a discharge tube is a high-voltage protection device. When the voltage across the discharge tube exceeds its rated range, it will short-circuit internally. A varistor, on the other hand, is a non-linear resistive device. When the voltage across the varistor is below its threshold, the current flowing through it is minimal, equivalent to a closed valve. When the voltage exceeds its threshold, its resistance decreases, causing the current flowing through it to surge. In other words, when encountering a high voltage exceeding the threshold values ​​of the first varistor MOV1, the second varistor MOV2, and the second discharge tube FDG2, the second discharge tube FDG2 short-circuits, and the first varistor MOV1 and the second varistor MOV2 approximately conduct, connecting the live wire input terminal ACL and the neutral wire input terminal ACN to the chassis ground, releasing the high voltage to effectively protect the subsequent circuitry.

[0041] The surge protection circuit also includes a second surge protection unit 32, which is located in the filter rectifier circuit 2. Specifically, the second surge protection unit 32 is connected between the first EMC unit 21 and the rectifier unit 22. Specifically, the second surge protection unit 32 includes a first TVS diode TSS1 and a third varistor MOV3. The first end of the first TVS diode TSS1 is connected to the first EMC unit 21, specifically connected to the second output end of the second common-mode inductor LF2 in the first EMC unit 21. The second end of the first TVS diode TSS1 is connected to the first end of the third varistor MOV3, and the second end of the third varistor MOV3 is connected to the second output end of the second common-mode inductor LF2.

[0042] Understandably, when input terminal 1 encounters high voltage input such as lightning strike, a momentary high voltage will be generated at input terminal 1. The resistance of the third varistor MOV3 will decrease momentarily, and the first TVS transistor TSS1 will be short-circuited internally for a moment. At the moment of encountering high voltage input such as lightning strike, the voltage across the AC input terminals of the bridge rectifier BD1 is clamped, effectively protecting the subsequent circuits.

[0043] Furthermore, the peak absorption circuit 33 is located between the power output terminal of the filter rectifier circuit 2 and the transformer T2. Specifically, the two ends of the peak absorption circuit 33 are connected to the second EMC unit 23 and the transformer T2, respectively. Specifically, the peak absorption circuit 33 includes a fifth diode D5, a surge-resistant twenty-seventh resistor R27 and a twenty-eighth resistor R28, and a third electrolytic capacitor CE3. The anode of the fifth diode D5 is connected to the power output terminal of the filter rectifier circuit 2, specifically connected to the second end of the first differential mode inductor L1. The cathode of the fifth diode D5 is connected to the positive terminal of the third electrolytic capacitor CE3, and the negative terminal of the third electrolytic capacitor CE3 is connected to the first ground terminal. The first end of the twenty-seventh resistor R27 is connected to the anode of the fifth diode D5, and the second end of the twenty-seventh resistor R27 is connected to the cathode of the fifth diode D5 via the twenty-eighth resistor R28.

[0044] Understandably, when the AC input circuit encounters a lightning strike spike, the peak value, after being current-limited by the resistor, charges the electrolytic capacitor. When the periodic spike transitions to the second half of the cycle, the electrolytic capacitor discharges through the current-limiting resistor, thus effectively protecting the subsequent circuitry. Simultaneously, because the electrolytic capacitor has a filtering function, it can filter the first DC power supply passing through the peak absorption circuit 33, resulting in a purer DC power supply.

[0045] Furthermore, the first lightning protection unit 31, the second lightning protection unit 32, and the peak absorption circuit 33 can be individually set in the driving switching power supply, or they can be a combination of two or all three set in the same driving switching power supply. When the above three circuit units are set in the same driving switching power supply, the lightning protection level can reach 10KV, which is the most effective.

[0046] Furthermore, transformer T2 is a flyback transformer, comprising a primary winding T2-A, a feedback winding T2-B, and a secondary winding T2-D. Specifically, the first end of the primary winding T2-A is connected to a second DC power supply, and the second end of the primary winding T2-A is connected to the control circuit 4, specifically to the drain of the first MOSFET Q1 in the control circuit 4; the first end of the feedback winding T2-B is connected to the control circuit 4, specifically, the first end of the feedback winding T2-B is sequentially connected to the voltage output regulation circuit 42 and the first controller U1 in the control circuit 4; the second end of the feedback winding T2-B is connected to the first ground terminal; and the two ends of the secondary winding T2-D are respectively connected to the power output circuit 5.

[0047] Optionally, transformer T2 is also connected to an RCD snubber circuit; the RCD snubber circuit can be used to reduce voltage spikes caused by leakage inductance in the transformer.

[0048] Furthermore, the control circuit 4 includes a first controller U1, several first voltage divider resistors for voltage division, several first filter capacitors for filtering, a first MOSFET Q1, an adjustable resistor circuit 41, and a voltage output regulation circuit 42. Specifically, one power output terminal of the filter rectifier circuit 2 is connected to the sixth pin of the first controller U1 for power supply through a portion of its first voltage divider resistors, and the other power output terminal of the filter rectifier circuit 2 is connected to the first pin of the first controller U1 for current compensation control through two portions of its first voltage divider resistors and a portion of its first filter capacitors; the fifth pin of the first controller U1 for outputting pulse signals is connected to the gate of the first MOSFET Q1, the drain of the first MOSFET Q1 is connected to the transformer T2, specifically the drain of the first MOSFET Q1 is connected to the second terminal of the primary winding T2-A, and the source of the first MOSFET Q1 is connected to the first ground terminal; the adjustable resistor circuit 41 is connected to the third pin of the first controller U1 for current detection, and the output current of the transformer T2 can be adjusted by adjusting the resistance value of the adjustable resistor circuit 41; the voltage output adjustment circuit 42 is connected to the eighth pin of the first controller U1 as the PWM dimming input, and is used to adjust the second DC power supply output by the transformer T2.

[0049] Furthermore, the voltage output regulation circuit 42 includes a second diode D2, a third transistor Q3, a first Zener diode ZD1, a first electrolytic capacitor CE1, a portion of the first voltage divider resistors used in the voltage output regulation circuit 42, and an eleventh resistor R11 used to clamp the voltage at a specified potential. The portion of the first voltage divider resistors used in the voltage output regulation circuit 42 includes a ninth resistor R9, a tenth resistor R10, and a twelfth resistor R12. Specifically, the anode of the second diode D2 is connected to the transformer T2, specifically to the first terminal of the feedback winding T2-B in the transformer T2; the cathode of the second diode D2 is connected to the collector of the third transistor Q3, the positive terminal of the first electrolytic capacitor CE1, and the second terminal of the eleventh resistor R11 through the ninth resistor R9; the base of the third transistor Q3 is connected to the first terminal of the eleventh resistor R11 and the cathode of the first Zener diode ZD1; the emitter of the third transistor Q3 is connected to the eighth pin of the first controller U1 through the twelfth resistor R12; the tenth resistor R10 is connected in parallel with the ninth resistor R9, and the two ends of the tenth resistor R10 are respectively connected to the two ends of the ninth resistor R9; the negative terminal of the first electrolytic capacitor CE1 and the anode of the first Zener diode ZD1 are both connected to the first ground terminal.

[0050] Furthermore, the first grounding terminal is the power supply ground.

[0051] Understandably, the output of transformer T2 can be adjusted by setting different specifications of the first voltage regulator ZD1.

[0052] Optionally, the first controller U1 can be a control chip of model SY5882AFAC. The second pin of the first controller U1 is connected to the first end of the feedback winding T2-B in transformer T2.

[0053] Furthermore, such as Figure 2 As shown, the power output circuit 5 includes a third common-mode inductor LF3, several second voltage divider resistors, a second filter capacitor, and an output capacitor. The output terminal of the power output circuit 5 can be connected to a load to supply power to it. For specific connection methods, please refer to the attached diagram in the instruction manual. Figure 1 I won't go into details here.

[0054] Based on the same concept, the present invention also constructs an outdoor LED lamp, including a light source module and a driving power supply device connected to the light source module; the driving power supply device includes the aforementioned primary-side controlled driving switching power supply.

[0055] The primary-side controlled drive switching power supply constructed in this invention includes a first lightning protection unit 31, a second lightning protection unit 32, and a peak absorption circuit 33 within a drive switching power supply that already has a filter and rectifier circuit 2. The first lightning protection unit 31 discharges the lightning current and clamps the voltage at the input connection terminal 1 when the drive switching power supply is struck by lightning, and automatically disconnects itself from the AC power supply when the lightning current is too large. The second lightning protection unit 32 cuts off the path between the AC power supply and the filter and rectifier circuit 2 when the first lightning protection unit 31 fails due to a lightning strike and the drive switching power supply is struck by lightning again. The peak absorption circuit 33 clamps the voltage between the input terminal and the corresponding output terminal when a voltage spike is generated at one of the input terminals of the filter and rectifier circuit 2 due to a lightning strike. The entire primary-side controlled drive switching power supply features surge protection, surge failure protection, and resistance to voltage spikes, enhancing surge protection levels to up to 10KV. This prevents damage from high-energy voltages such as lightning strikes, effectively protecting the circuit and improving its safety. It can be applied to outdoor drive power supplies. Furthermore, transformer isolation further improves circuit safety, simplifies the external circuitry, and reduces circuit costs.

[0056] It is understood that the above embodiments only illustrate preferred embodiments of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can freely combine the above technical features without departing from the concept of the present invention, and can also make several modifications and improvements, all of which fall within the protection scope of the present invention. Therefore, all equivalent transformations and modifications made with respect to the scope of the claims of the present invention should fall within the scope of the claims of the present invention.

Claims

1. A primary-side controlled driving switching power supply, characterized in that, The drive switching power supply comprises an input connection end (1), a filter rectifier circuit (2), a control circuit (4), a transformer T2 and a power output circuit (5) connectable with a load. The input connection end (1) is connected with the filter rectifier circuit (2) and is connected to an AC power supply as an AC input circuit and outputs a first DC power supply after filtering and rectifying the AC power supply; a power output end of the filter rectifier circuit (2) is connected with the control circuit (4) in a first path and is connected with the transformer T2 in a second path; the transformer T2 is connected with the control circuit (4) and the power output circuit (5) respectively, and the control circuit (4) controls the transformer T2 to convert the first DC power supply into a second DC power supply and outputs the second DC power supply to the load through the power output circuit (5); The filter rectifier circuit (2) comprises a first EMC unit (21), a rectifier unit (22) and a second EMC unit (23); a first end of the first EMC unit (21) is connected with the input connection end (1), a second end of the first EMC unit (21) is connected with the rectifier unit (22) and then connected with a first end of the second EMC unit (23), and a second end of the second EMC unit (23) is connected with the control circuit (4) in one path and connected with the transformer T2 in another path; The rectifier unit (22) comprises a bridge rectifier BD1; The drive switching power supply further comprises a lightning protection circuit and a peak absorption circuit (33); the lightning protection circuit is arranged in the AC input circuit; the peak absorption circuit (33) is connected with a power output end of the filter rectifier circuit (2) and is located in front of the control circuit (4) and is used for absorbing a lightning peak encountered by the AC input circuit and filtering the first DC power supply output; The lightning protection circuit comprises a first lightning protection unit (31) and a second lightning protection unit (32); the first lightning protection unit (31) is arranged between the input connection end (1) and the filter rectifier circuit (2) and is connected with the input connection end (1) and the filter rectifier circuit (2) respectively, so as to release a high-voltage power supply input into the AC input circuit to a case ground; the second lightning protection unit (32) is arranged in the filter rectifier circuit (2) and is connected between the first EMC unit (21) and the bridge rectifier BD1, so as to clamp a voltage between two AC input ends of the bridge rectifier BD1 when a high-voltage input is encountered; The peak absorption circuit (33) comprises a fifth diode D5, a twenty-seventh resistor R27 and a twenty-eighth resistor R28 which can resist a surge, and a third electrolytic capacitor CE3. Anode of the fifth diode D5 is connected to one end of the transformer T2 in the second EMC unit (23), cathode of the fifth diode D5 is connected to positive pole of the third electrolytic capacitor CE3, negative pole of the third electrolytic capacitor CE3 is connected to first ground terminal; first end of the twenty-seventh resistor R27 is connected to anode of the fifth diode D5, second end of the twenty-seventh resistor R27 is connected to cathode of the fifth diode D5 through the twenty-eighth resistor R28.

2. The primary-side controlled driving switching mode power supply of claim 1, wherein, The input connection end (1) comprises an active line input end ACL for connecting an active line, a neutral line input end ACN for connecting a neutral line, and a ground line input end PG1 for connecting a ground line.

3. The primary side controlled driving switching mode power supply of claim 2, wherein, The first lightning protection unit (31) comprises a first MOV MOV1, a second MOV MOV2, and a second discharge tube FDG2; two ends of the first MOV MOV1 are connected to the active line input end ACL and the neutral line input end ACN respectively; a first end of the second MOV MOV2 is connected to the neutral line input end ACN, and a second end of the second MOV MOV2 is connected to the case ground through the second discharge tube FDG2.

4. The primary side controlled driving switching mode power supply of claim 3, wherein, The first EMC unit (21) comprises a first common mode inductor LF1, a first capacitor CY1, a second capacitor CY2, a third capacitor CX1, a first discharge tube FDG1, and a second common mode inductor LF2. A first input end of the first common mode inductor LF1 is connected to the active line input end ACL, a second input end of the first common mode inductor LF1 is connected to the neutral line input end ACN, a first output end of the first common mode inductor LF1 is connected to a first end of the second capacitor CY2, a first end of the third capacitor CX1, and a first input end of the second common mode inductor LF2; a second end of the third capacitor CX1 and a second input end of the second common mode inductor LF2 are connected to a second output end of the first common mode inductor LF1, and the second output end of the first common mode inductor LF1 is connected to the case ground through the first capacitor CY1; the ground line input end PG1 and a second end of the second capacitor CY2 are connected to the case ground; a first output end and a second output end of the second common mode inductor LF2 are connected to the rectifier unit (22) respectively; two ends of the first discharge tube FDG1 are connected to the first input end and the first output end of the second common mode inductor LF2 respectively.

5. The primary side controlled driving switching mode power supply of claim 4, wherein, The second lightning protection unit (32) comprises a first TVS tube TSS1 and a third MOV MOV3; a first end of the first TVS tube TSS1 is connected to the first EMC unit (21), a second end of the first TVS tube TSS1 is connected to a first end of the third MOV MOV3, and a second end of the third MOV MOV3 is connected to a second output end of the second common mode inductor LF2.

6. The primary side controlled driving switching mode power supply of claim 1 or 2, wherein, The control circuit (4) comprises a first controller U1, a plurality of first voltage dividing resistors for voltage division, a plurality of first filter capacitors for filtering, a first MOS tube Q1, an adjustable resistor circuit (41), and a voltage output adjusting circuit (42). The power output end of the filter rectifier circuit (2) is connected to the sixth pin of the first controller U1 for power supply through one part of the first voltage dividing resistor, and is connected to the first pin of the first controller U1 for current compensation control through two parts of the first voltage dividing resistor and one part of the first filter capacitor; the fifth pin of the first controller U1 for outputting pulse signals is connected to the gate of the first MOS tube Q1, and the drain of the first MOS tube Q1 is connected to the transformer T2; the adjustable resistor circuit (41) is connected to the third pin of the first controller U1 for current detection, and the output current of the transformer T2 can be adjusted by adjusting the resistance value of the adjustable resistor circuit (41); the voltage output adjustment circuit (42) is connected to the eighth pin of the first controller U1 as the PWM dimming input, for adjusting the second DC power output by the transformer T2.

7. The primary side controlled driving switching mode power supply of claim 6, wherein, The first controller U1 is a control chip with a model number of SY5882AFAC. 8.An outdoor LED lamp, comprising a light source module and a driving power supply device connected to the light source module; the driving power supply device comprises the primary side controlled driving switching power supply of any one of claims 1-7.

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