High-PF (power factor) LED (light-emitting diode) driving device and illuminating lamp

Abstract

The utility model discloses a high-PF LED driving device and an illumination lamp. The device comprises a rectification circuit, a filter circuit, a PF compensation circuit and a constant current driving circuit. The rectifying circuit is connected with an external alternating current power supply and is used for converting alternating current mains supply into direct current; the filter circuit is respectively connected with the rectifying circuit, the PF compensating circuit and the constant-current driving circuit, and is used for filtering the direct current and respectively supplying power to the PF compensating circuit and the constant-current driving circuit in an adaptive manner; the constant current driving circuit is connected with the PF compensation circuit and the light source module and used for driving the light source module to work in a constant current mode. According to the utility model, the PF can be improved, the PF value is high, the circuit structure is simple, the cost is low, and the actual requirements of users can be met.

Description

Technical Field

[0001] The utility model relates to the technical field of lighting, and in particular to a high PF LED driving device and a lighting fixture. Background Art

[0002] With the rapid development of the lighting industry, more and more LED lighting products have extremely high requirements for PF (power factor), especially for many bidding products, PF>0.98. It is very difficult for low-power (less than 7W) drivers to achieve PF>0.98. At present, most of the industry has achieved 0.9 performance. If it needs to be improved to 0.98, the usual practice is to use a two-stage design for the driver. However, the circuit of this architecture is complex, the number of components involved is large, the cost is extremely high, and the cost-effectiveness is low, which cannot meet the actual needs of users. Utility Model Content

[0003] The technical problem to be solved by the utility model is to provide a high PF LED driving device and lighting fixture, which can achieve PF improvement, high PF value, simple circuit structure, low cost, and can meet the actual needs of users.

[0004] In order to solve the above technical problems, the utility model provides a high PF LED driving device, including a rectifier circuit, a filter circuit, a PF compensation circuit and a constant current drive circuit; the rectifier circuit is connected to an external AC power supply, and is used to convert AC mains power into DC power; the filter circuit is respectively connected to the rectifier circuit, the PF compensation circuit and the constant current drive circuit, and is used to filter the DC power and adapt power supply to the PF compensation circuit and the constant current drive circuit respectively; the constant current drive circuit is respectively connected to the PF compensation circuit and the light source module, and is used to drive the light source module to operate at a constant current.

[0005] As an improvement of the above scheme, the PF compensation circuit includes a first resistor, a second resistor, a third resistor, a first capacitor and a second capacitor; one end of the first resistor is respectively connected to the output end of the filter circuit and the input end of the constant current drive circuit, the other end of the first resistor is grounded via the second resistor and the third resistor in sequence, the connection end between the second resistor and the third resistor is connected to the compensation end of the constant current drive circuit via the first capacitor, and the compensation end of the constant current drive circuit is grounded via the second capacitor.

[0006] As an improvement of the above scheme, the constant current drive circuit includes an output circuit, a transformer module, a first electrolytic capacitor, a voltage divider circuit, a fourth resistor, a third capacitor, a first diode, a sampling module and a constant current drive chip, wherein the constant current drive chip includes a power supply pin, a feedback pin, a compensation pin, an output pin, a sampling pin and a ground pin; the transformer module includes a first winding and a second winding, the first end of the first winding is connected to the filter circuit, the second end is connected to the output circuit, and the output circuit is connected to the light source module; the first end of the second winding is respectively connected to the positive end of the first diode and the voltage divider circuit, and the second end is grounded; the negative end of the first diode is respectively connected to the power supply pin and the positive end of the first electrolytic capacitor through the fourth resistor, the negative end of the first electrolytic capacitor is grounded, the voltage divider end of the voltage divider circuit is connected to the feedback pin and grounded through the third capacitor; the ground pin is grounded, the output pin is connected to the output circuit, the sampling pin is grounded through the sampling module, and the compensation pin is connected to the compensation circuit.

[0007] As an improvement of the above scheme, the voltage divider circuit includes a first voltage divider resistor and a second voltage divider resistor, one end of the first voltage divider resistor is connected to the first end of the second winding, and the other end of the first voltage divider resistor is grounded via the second voltage divider resistor; the connecting end between the first voltage divider resistor and the second voltage divider resistor is connected to the feedback pin and grounded via the third capacitor.

[0008] As an improvement of the above solution, the sampling module includes at least one sampling resistor.

[0009] As an improvement of the above scheme, the output circuit includes a second diode, a fifth resistor and a second electrolytic capacitor, the positive terminal of the second diode is respectively connected to the second end of the second winding and the output pin, and the negative terminal of the second diode is connected to the positive terminal of the second electrolytic capacitor; the negative terminal of the second electrolytic capacitor is connected to the first end of the first winding, and the second electrolytic capacitor is respectively connected in parallel with the fifth resistor and the light source module.

[0010] As an improvement of the above scheme, the rectifier circuit includes a fuse, a sixth resistor, a seventh resistor, an eighth resistor, a safety capacitor, an inductor and a rectifier bridge; the first AC input end of the rectifier bridge is connected to one end of the safety capacitor via the inductor and the sixth resistor respectively, one end of the safety capacitor is connected to the live wire end of the power supply via the fuse, the second AC input end of the rectifier is connected to the other end of the safety capacitor and the neutral wire end of the power supply respectively, the first output end of the rectifier bridge is connected to the filter circuit, and the second output end of the rectifier bridge is connected to the filter circuit; one end of the seventh resistor is connected to one end of the safety capacitor, and the other end of the seventh resistor is connected to the other end of the safety capacitor via the eighth resistor.

[0011] As an improvement of the above solution, the rectifier circuit further includes a first safety resistor, which is connected in parallel with the safety capacitor.

[0012] As an improvement of the above scheme, the filtering circuit includes a fourth capacitor, a magnetic bead and a second safety resistor, one end of the fourth capacitor is respectively connected to the output end of the rectifier circuit and the input end of the constant current drive circuit, the other end of the fourth capacitor is connected to the second output end of the rectifier circuit, the other end of the fourth capacitor is grounded via the magnetic bead, and the second safety resistor is connected in parallel with the fourth capacitor.

[0013] The utility model also provides a lighting fixture, comprising a lamp body and the above-mentioned high-PF LED driving device, wherein the high-PF LED driving device is packaged in the lamp body.

[0014] The beneficial effects of implementing the utility model are:

[0015] The utility model can achieve PF improvement through the PF compensation circuit provided, so that the PF value is high, which can meet the high PF usage needs of users; the light source module can be driven to work at a constant current through the constant current driving circuit provided; the circuit interference can be filtered out through the filter circuit provided, and the circuit structure is simple and the cost is low, which can meet the actual needs of users. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic diagram of the structure of the high PF LED driving device of the utility model;

[0017] Figure 2 This is a circuit structure diagram of a high PF LED driving device of the utility model. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solutions and advantages of the utility model clearer, the utility model will be further described in detail below with reference to the accompanying drawings.

[0019] like Figure 1 As shown, a specific embodiment of the utility model provides a high PF LED driving device, including a rectifier circuit 1, a filter circuit 2, a PF compensation circuit 3 and a constant current driving circuit 4;

[0020] The rectifier circuit 1 is connected to an external AC power supply, and is used to convert AC mains power into DC power to power the entire circuit. The filter circuit 2 is respectively connected to the output end of the rectifier circuit 1, and is used to filter the DC power to filter out circuit interference and improve circuit stability. The filter circuit 2 is also connected to the PF compensation circuit 3 and the constant current drive circuit 4, and is used to adapt the filtered DC power to the PF compensation circuit 3 and the constant current drive circuit 4 for power supply. The constant current drive circuit 4 is respectively connected to the PF compensation circuit 3 and the light source module, and the PF compensation circuit 3 is connected to the compensation end of the constant current drive circuit 4, and is used to achieve PF compensation improvement, so that the PF value is high, which can meet the user's high PF usage requirements; the constant current drive circuit 4 is used to drive the light source module to work at a constant current. The circuit structure of the utility model is simple, the cost is low, and it can meet the actual needs of users.

[0021] Preferably, the light source module comprises at least one group of LED modules, and each group of LED modules comprises a plurality of light emitting diodes connected in series.

[0022] The following is a detailed description of the present invention in conjunction with a specific circuit diagram:

[0023] like Figure 2 As shown, Figure 2 The circuit structure diagram of the high PF LED driving device of the utility model is shown, and the rectifier circuit 1, the filter circuit 2, the PF compensation circuit 3 and the constant current driving circuit 4 are described below respectively:

[0024] 1. Rectifier circuit 1

[0025] The rectifier circuit 1 includes a fuse FR1, a sixth resistor R1, a seventh resistor R6, an eighth resistor R7, a safety capacitor CX1, an inductor L1 and a rectifier bridge BD1;

[0026] The first AC input end of the rectifier bridge BD1 is connected to one end of the safety capacitor CX1 through the inductor L1 and the sixth resistor R1, one end of the safety capacitor CX1 is connected to the live wire end of the power supply through the fuse FR1, the second AC input end of the rectifier is connected to the other end of the safety capacitor CX1 and the neutral wire end of the power supply, the first output end of the rectifier bridge BD1 is connected to the filter circuit 2, and the second output end of the rectifier bridge BD1 is connected to the filter circuit 2; one end of the seventh resistor R6 is connected to one end of the safety capacitor CX1, and the other end of the seventh resistor R6 is connected to the other end of the safety capacitor CX1 through the eighth resistor R7. The input AC power is filtered by the inductor L1 and the safety capacitor CX1 and then rectified by the rectifier bridge BD1 to provide the DC power required for the subsequent circuit.

[0027] The inductor L1 is preferably a differential mode inductor, but is not limited thereto.

[0028] Furthermore, the rectifier circuit 1 further includes a first fuse resistor VR1, which is connected in parallel with the safety capacitor CX1. The first fuse resistor VR1 can effectively absorb surges and provide system stability.

[0029] Preferably, the first fuse resistor VR1 is preferably a varistor, but is not limited thereto, and other fuse resistors with circuit protection functions, such as a thermistor, may also be selected according to actual needs.

[0030] 2. Filter circuit 2

[0031] The filter circuit 2 includes a fourth capacitor C1, a magnetic bead BL and a second insurance resistor VR2;

[0032] One end of the fourth capacitor C1 is connected to the output end of the rectifier circuit 1 and the input end of the constant current drive circuit 4, respectively; the other end of the fourth capacitor C1 is connected to the second output end of the rectifier circuit 1; the other end of the fourth capacitor C1 is grounded via the magnetic bead BL; and the second insurance resistor VR2 is connected in parallel with the fourth capacitor C1. The direct current output by the rectifier circuit 1 is filtered through the fourth capacitor C1 and the magnetic bead BL to filter out circuit interference.

[0033] Preferably, the second fuse resistor VR2 is preferably a varistor, but it is not limited thereto, and other fuse resistors with circuit protection functions, such as thermistors, can also be selected according to actual needs. The second fuse resistor VR2 can effectively absorb surges and provide system stability.

[0034] 3. PF compensation circuit 3

[0035] The PF compensation circuit 3 includes a first resistor R8, a second resistor R9, a third resistor R10, a first capacitor C3 and a second capacitor C5;

[0036] One end of the first resistor R8 is connected to the output end of the filter circuit 2 and the input end of the constant current drive circuit 4, respectively. The other end of the first resistor R8 is connected to the ground via the second resistor R9 and the third resistor R10 in turn. The connection end between the second resistor R9 and the third resistor R10 is connected to the compensation end of the constant current drive circuit 4 (i.e., the compensation pin of the constant current drive chip) via the first capacitor C3 and is connected to the ground via the second capacitor C5. After the DC power is filtered by the filter circuit 2, the DC power is high-voltage electricity is taken, and the PF compensation circuit 3 is formed by the first resistor R8, the second resistor R9, the third resistor R10, the first capacitor C3 and the second capacitor C5 to perform PF compensation, and the PF compensation circuit 3 is connected to the compensation end of the constant current drive circuit 4 to achieve PF compensation improvement, so that the PF value is high, which can meet the user's high PF usage requirements.

[0037] 4. Constant current drive circuit 4

[0038] The constant current drive circuit 4 includes an output circuit 41, a transformer module T1, a first electrolytic capacitor EC2, a voltage divider circuit 42, a fourth resistor R2, a third capacitor C2, a first diode D2, a sampling module 43 and a constant current drive chip U1, wherein the constant current drive chip U1 includes a power supply pin V11, a feedback pin FB, a compensation pin COMP, an output pin DRAIN, a sampling pin CS and a ground pin GND;

[0039] The transformer module T1 includes a first winding and a second winding, the first end of the first winding is connected to the filter circuit 2, and the second end is connected to the output circuit 41, and the output circuit 41 is connected to the; the first end of the second winding is respectively connected to the positive terminal of the first diode D2 and the voltage divider circuit 42, and the second end is grounded; the negative terminal of the first diode D2 is respectively connected to the power supply pin and the positive terminal of the first electrolytic capacitor EC2 via the fourth resistor R2, the negative terminal of the first electrolytic capacitor EC2 is grounded, the voltage divider end of the voltage divider circuit 42 is connected to the feedback pin and grounded via the third capacitor C2; the ground pin is grounded, the output pin is connected to the output circuit 41, the sampling pin is grounded via the sampling module 43, and the compensation pin is connected to the compensation circuit.

[0040] Among them, the constant current driver chip U1 has a built-in switch-controlled MOS tube, which can control the second winding in the transformer module T1 to store and discharge energy and provide energy to the load by turning on and off the built-in MOS tube. Preferably, the constant current driver chip U1 is preferably BP3336, but it is not limited to this and can be adjusted according to actual needs.

[0041] Preferably, the voltage divider circuit 42 includes a first voltage divider resistor R3 and a second voltage divider resistor R4, one end of the first voltage divider resistor R3 is connected to the first end of the second winding, and the other end of the first voltage divider resistor R3 is grounded via the second voltage divider resistor R4; the connection end between the first voltage divider resistor R3 and the second voltage divider resistor R4 is connected to the feedback pin and grounded via the third capacitor C2. The voltage divider ratio can be set by the first voltage divider resistor R3 and the second voltage divider resistor R4 in the voltage divider circuit 42 to drive the output of a no-load voltage.

[0042] Furthermore, the sampling module 43 includes two sampling resistors (such as RS1 and RS2). The constant current driver chip U1 can set the output constant current value by connecting the sampling module 43 to the sampling pin, which is flexible. In other embodiments, the number and resistance of the sampling resistors of the sampling module 43 can be adjusted according to actual needs.

[0043] Preferably, the output circuit 41 includes a second diode D1, a fifth resistor R5 and a second electrolytic capacitor EC1, the positive terminal of the second diode D1 is connected to the second end of the second winding and the output pin respectively, the negative terminal of the second diode D1 is connected to the positive terminal of the second electrolytic capacitor EC1; the negative terminal of the second electrolytic capacitor EC1 is connected to the first end of the first winding, and the second electrolytic capacitor EC1 is connected in parallel with the fifth resistor R5 and the light source module respectively. The output circuit 41 is provided to provide stable direct current to the light source module, thereby improving the stability of lighting work.

[0044] Preferably, the utility model further provides a lighting fixture, comprising a lamp body and the above-mentioned high PF LED driving device, wherein the high PF LED driving device is encapsulated in the lamp body. Since the above-mentioned high PF LED driving device has the above-mentioned technical effects, the lighting fixture comprising the above-mentioned high PF LED driving device should also have the above-mentioned technical effects, which will not be described in detail here.

[0045] The above is a preferred embodiment of the present utility model. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present utility model.

Claims

1. A high PF LED driving device, characterized in that: It includes a rectifier circuit, a filter circuit, a PF compensation circuit and a constant current drive circuit; The rectifier circuit is connected to an external AC power source and is used to convert AC mains power into DC power; The filter circuit is connected to the rectifier circuit, the PF compensation circuit and the constant current drive circuit respectively, and is used to filter the DC power and supply power to the PF compensation circuit and the constant current drive circuit respectively; The constant current driving circuit is connected to the PF compensation circuit and the light source module respectively, and is used to drive the light source module to operate at a constant current.

2. The high PF LED driving device according to claim 1, characterized in that: The PF compensation circuit includes a first resistor, a second resistor, a third resistor, a first capacitor and a second capacitor; One end of the first resistor is connected to the output end of the filter circuit and the input end of the constant current drive circuit respectively, the other end of the first resistor is grounded via the second resistor and the third resistor in sequence, the connection end between the second resistor and the third resistor is connected to the compensation end of the constant current drive circuit via the first capacitor, and the compensation end of the constant current drive circuit is grounded via the second capacitor.

3. The high PF LED driving device according to claim 1, characterized in that: The constant current drive circuit includes an output circuit, a transformer module, a first electrolytic capacitor, a voltage divider circuit, a fourth resistor, a third capacitor, a first diode, a sampling module and a constant current drive chip, and the constant current drive chip includes a power supply pin, a feedback pin, a compensation pin, an output pin, a sampling pin and a ground pin; The transformer module includes a first winding and a second winding, wherein a first end of the first winding is connected to the filter circuit, and a second end is connected to the output circuit, and the output circuit is connected to the light source module; a first end of the second winding is respectively connected to the positive terminal of the first diode and the voltage divider circuit, and a second end is grounded; The negative terminal of the first diode is connected to the power supply pin and the positive terminal of the first electrolytic capacitor respectively via the fourth resistor, the negative terminal of the first electrolytic capacitor is grounded, and the voltage dividing end of the voltage dividing circuit is connected to the feedback pin and grounded via the third capacitor; The ground pin is grounded, the output pin is connected to the output circuit, the sampling pin is grounded via the sampling module, and the compensation pin is connected to the compensation circuit.

4. The high PF LED driving device according to claim 3, characterized in that: The voltage-dividing circuit comprises a first voltage-dividing resistor and a second voltage-dividing resistor, one end of the first voltage-dividing resistor is connected to the first end of the second winding, and the other end of the first voltage-dividing resistor is grounded via the second voltage-dividing resistor; A connection end between the first voltage-dividing resistor and the second voltage-dividing resistor is connected to the feedback pin and is grounded via the third capacitor.

5. The high PF LED driving device according to claim 3, characterized in that: The sampling module includes at least one sampling resistor.

6. The high PF LED driving device according to claim 3, characterized in that: The output circuit comprises a second diode, a fifth resistor and a second electrolytic capacitor, the positive terminal of the second diode is connected to the second end of the second winding and the output pin respectively, and the negative terminal of the second diode is connected to the positive terminal of the second electrolytic capacitor; A negative terminal of the second electrolytic capacitor is connected to the first end of the first winding, and the second electrolytic capacitor is connected in parallel with the fifth resistor and the light source module respectively.

7. The high PF LED driving device according to claim 1, characterized in that: The rectifier circuit includes a fuse, a sixth resistor, a seventh resistor, an eighth resistor, a safety capacitor, an inductor and a rectifier bridge; The first AC input end of the rectifier bridge is connected to one end of the safety capacitor via the inductor and the sixth resistor respectively, one end of the safety capacitor is connected to the live wire end of the power supply via a fuse, the second AC input end of the rectifier is connected to the other end of the safety capacitor and the neutral wire end of the power supply respectively, the first output end of the rectifier bridge is connected to the filter circuit, and the second output end of the rectifier bridge is connected to the filter circuit; One end of the seventh resistor is connected to one end of the safety capacitor, and the other end of the seventh resistor is connected to the other end of the safety capacitor via the eighth resistor.

8. The high PF LED driving device according to claim 7, characterized in that: The rectifier circuit further includes a first safety resistor, which is connected in parallel with the safety capacitor.

9. The high PF LED driving device according to claim 1, characterized in that: The filtering circuit includes a fourth capacitor, a magnetic bead and a second safety resistor, one end of the fourth capacitor is respectively connected to the output end of the rectifier circuit and the input end of the constant current drive circuit, the other end of the fourth capacitor is connected to the second output end of the rectifier circuit, the other end of the fourth capacitor is grounded via the magnetic bead, and the second safety resistor is connected in parallel to the fourth capacitor.

10. A lighting fixture, characterized in that: The invention comprises a lamp body and a high-PF LED driving device according to any one of claims 1 to 9, wherein the high-PF LED driving device is packaged in the lamp body.

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