A current harmonic-based LED driving power supply structure optimization method and system

Abstract

The application discloses a kind of based on current harmonic LED drive power structure optimization method and system, comprising: according to LED port voltage and the working parameter of flyback converter, the magnetic flux sequence and current sequence of the primary side inductance of transformer are obtained;Wherein, LED drive power structure includes uncontrolled rectifier circuit, LC filter circuit and the flyback converter consisting of transformer;Each time in the magnetic flux time table expression of the primary side inductance of transformer is traversed, and based on magnetic flux sequence and current sequence, the current value of each traversal time is inquired to constitute the time sequence of current expression;The current harmonic of LED port is calculated to obtain in combination with the time sequence of current expression, and according to LED port current harmonic, LED drive power structure is optimized.The application is analyzed by inductance saturation characteristic, and the current harmonic problem caused by flyback converter transformer saturation is fully considered, so as to realize the optimization of LED drive power structure.

Description

Technical Field

[0001] This invention relates to the field of power electronics technology, and in particular to a method and system for optimizing the structure of an LED driver power supply based on current harmonics. Background Technology

[0002] With the development of lighting technology, light-emitting diodes (LEDs) are increasingly used in various lighting applications. LED driving can be mainly divided into constant current driving and pulsating current driving. However, since constant current driving LEDs require electrolytic capacitors in their adapters, the lifespan of the LED is limited by the lifespan of the electrolytic capacitors, restricting the improvement of LED lifespan. Pulsating current driving, on the other hand, only requires capacitors to filter out high-frequency ripple in the current, i.e., current harmonics of the switching frequency and its multiples. Therefore, its capacitance is very small, and film capacitors or ceramic capacitors can be used instead of electrolytic capacitors, thus greatly improving the lifespan of the driver power supply. The driver power supply structure for capacitor-free LEDs consists of "uncontrolled rectification + power factor correction (PFC) converter + LC filter." The PFC converter generally uses a flyback converter and operates it in discontinuous current mode. With a constant duty cycle, the average input current of the flyback converter is proportional to the input voltage. Therefore, a flyback converter operating in discontinuous current mode can automatically achieve power factor correction.

[0003] Due to the widespread application of LEDs, the component parameters of LEDs are often quite extreme in actual manufacturing and design to save costs. This may cause the flyback converter transformer in the LED driver to saturate, which in turn leads to current harmonics at the LED port. Therefore, analyzing the current harmonics at the LED port is a particularly critical step for optimizing the LED driver power supply structure. Summary of the Invention

[0004] This invention provides a method and system for optimizing the structure of an LED driver power supply based on current harmonics. It considers the current harmonic problem caused by the saturation of the flyback converter transformer and achieves performance optimization of the LED driver power supply structure.

[0005] To address the aforementioned technical problems, embodiments of the present invention provide a method for optimizing the structure of an LED driver power supply based on current harmonics, comprising:

[0006] Based on the LED port voltage and the operating parameters of the flyback converter, the inductance saturation characteristics of the LED driver power supply structure are analyzed to obtain the flux sequence and current sequence of the primary inductance of the transformer; wherein, the LED driver power supply structure consists of an uncontrolled rectifier circuit, the flyback converter and an LC filter circuit, and the flyback converter is composed of the transformer;

[0007] Iterate through each moment in the flux-time expression of the primary inductance of the transformer, use the min function to query the sequence number corresponding to the current traversal moment in the flux sequence, and obtain the current value corresponding to each sequence number in the current sequence to form the time sequence of the current expression.

[0008] According to the preset harmonic component algorithm, combined with the time series of the current expression, the corresponding LED port current harmonics are calculated, and the LED driver power supply structure is optimized based on the LED port current harmonics.

[0009] By implementing the embodiments of the present invention, the inductance saturation characteristics of the LED driver power supply structure are analyzed, and the LED port current harmonics are derived and calculated based on the flux sequence and current sequence of the primary inductance of the transformer obtained from the analysis. This fully considers the current harmonic problem caused by the saturation of the flyback converter transformer due to extreme LED component parameters. Then, based on the calculated LED port current harmonics, the LED driver power supply structure is optimized to further improve the performance of the power grid system, reduce excessive losses on LED components, and overcome the limitation of LED component lifespan caused by extreme LED component parameters.

[0010] As a preferred embodiment, the LED port current harmonics are calculated according to a preset harmonic component algorithm and the time series of the current expression, and the LED driver power supply structure is optimized based on the LED port current harmonics, specifically as follows:

[0011] Based on each moment in the flux-time expression of the primary inductance of the transformer, a first time series is constructed, and by combining the first time series and the time series of the current expression, the multiple harmonic components of the corresponding LED port current are calculated to constitute the LED port current harmonics.

[0012] The LED driver power supply structure is optimized based on the harmonics of the LED port current.

[0013] Among them, the LED port current of the first The expression for the subharmonic component is as follows:

[0014]

[0015] In the formula: This refers to the first moment in the first time series. This refers to the last moment in the first time series. For the first time series, the first At that moment, The time series of the current expression is the first... A current value For harmonic order, This refers to the LED port voltage frequency.

[0016] In a preferred embodiment of the present invention, a first time sequence and a time sequence of the current expression are constructed based on the flux-time expression of the primary inductance of the transformer. Then, according to a preset harmonic component algorithm, the multiple harmonic components of the LED port current are calculated by combining the current values ​​corresponding to each moment in the first time sequence and each moment in the time sequence of the current expression. This enables harmonic analysis of the grid-connected current in the LED driver power supply structure. Based on the LED port current harmonics composed of multiple harmonic components, further optimization of the LED driver power supply structure can be achieved.

[0017] As a preferred embodiment, the inductor saturation characteristic analysis of the LED driver power supply structure is performed based on the LED port voltage and the operating parameters of the flyback converter to obtain the flux sequence and current sequence of the primary inductance of the transformer, specifically as follows:

[0018] The LED port voltage and the operating parameters of the flyback converter are obtained, and the corresponding LED port voltage peak value is collected based on the LED port voltage; wherein, the operating parameters of the flyback converter include the flyback converter duty cycle, switching frequency, and the primary side static inductance of the transformer;

[0019] Using the peak voltage of the LED port and the operating parameters of the flyback converter, the inductance saturation characteristics of the LED driver power supply structure are analyzed to obtain the saturation characteristics of the primary inductance of the transformer, and the core hysteresis curve of the primary inductance of the transformer is plotted. Then, based on the core hysteresis curve, the flux sequence and the current sequence of the primary inductance of the transformer are obtained.

[0020] In a preferred embodiment of the present invention, based on the flyback converter's operating parameters such as duty cycle, switching frequency, and primary-side static inductance of the transformer, as well as the LED port voltage, the peak value of the primary-side inductor current of the transformer can be derived, thereby obtaining the saturation characteristics of the primary-side inductor. Based on these saturation characteristics, the core hysteresis curve of the primary-side inductor of the transformer can be plotted, realizing the acquisition of the flux sequence and current sequence of the primary-side inductor of the transformer, so as to perform subsequent calculation and analysis of the harmonic components of the LED port current.

[0021] As a preferred embodiment, the uncontrolled rectifier circuit includes a first rectifier diode, a second rectifier diode, a third rectifier diode, and a fourth rectifier diode;

[0022] In this configuration, the cathode of the first rectifier diode is connected to the cathode of the third rectifier diode, the anode of the third rectifier diode is connected to the cathode of the fourth rectifier diode, the anode of the fourth rectifier diode is connected to the anode of the second rectifier diode, the cathode of the second rectifier diode is connected to the anode of the first rectifier diode, the anode of the first rectifier diode is connected to the first terminal of the output side of the mains voltage, the second terminal of the output side of the mains voltage is connected to the anode of the third rectifier diode, the cathode of the third rectifier diode is connected to the first terminal of the primary winding of the transformer, and the anode of the fourth rectifier diode is connected to the second terminal of the primary winding of the transformer via a switching transistor.

[0023] In a preferred embodiment of the present invention, the AC voltage provided by the power grid system is converted into DC voltage by utilizing the unidirectional conductivity of the first, second, third, and fourth rectifier diodes in the uncontrolled rectifier circuit, thereby achieving rectification processing of the voltage signal output from the output side of the power grid voltage and providing a stable DC voltage signal for the flyback converter.

[0024] As a preferred embodiment, the LC filter circuit includes an output capacitor and an output inductor;

[0025] Wherein, the first end of the output capacitor is connected to the first end of the output inductor, the first end of the output capacitor is connected to the first end of the flyback winding of the transformer via a flyback diode, the second end of the flyback winding of the transformer is connected to the second end of the output inductor, the second end of the output inductor is connected to the anode of the LED, and the cathode of the LED is connected to the second end of the output capacitor.

[0026] In a preferred embodiment of the present invention, an LC filter circuit consisting of an output capacitor and an output inductor can make the waveform of the LED port current smoother, thereby optimizing the structural performance of the LED driver power supply.

[0027] To address the same technical problem, embodiments of the present invention also provide an LED driver power supply structure optimization system based on current harmonics, comprising:

[0028] The saturation characteristic analysis module is used to perform inductance saturation characteristic analysis on the LED driver power supply structure based on the LED port voltage and the operating parameters of the flyback converter, so as to obtain the flux sequence and current sequence of the primary inductance of the transformer; wherein, the LED driver power supply structure consists of an uncontrolled rectifier circuit, the flyback converter and an LC filter circuit, and the flyback converter is composed of the transformer;

[0029] The sequence construction module is used to traverse each moment in the flux-time expression of the primary inductance of the transformer, and use the min function to query the sequence number corresponding to the current traversal moment in the flux sequence, and obtain the current value corresponding to each sequence number in the current sequence to form the time sequence of the current expression.

[0030] The structure optimization module is used to calculate the corresponding LED port current harmonics according to a preset harmonic component algorithm and the time series of the current expression, and to optimize the LED driver power supply structure based on the LED port current harmonics.

[0031] As a preferred embodiment, the structure optimization module specifically includes a harmonic component calculation unit and a structure optimization unit;

[0032] The harmonic component calculation unit is used to construct a first time series based on each moment in the flux-time expression of the primary inductance of the transformer, and combine the first time series with the time series of the current expression to calculate the corresponding multiple harmonic components of the LED port current, thereby constituting the LED port current harmonics; wherein, the first harmonic component of the LED port current... The expression for the subharmonic component is as follows:

[0033]

[0034] In the formula: This refers to the first moment in the first time series. This refers to the last moment in the first time series. For the first time series, the first At that moment, The time series of the current expression is the first... A current value For harmonic order, The LED port voltage frequency;

[0035] The structure optimization unit is used to optimize the LED driver power supply structure based on the harmonics of the LED port current.

[0036] As a preferred embodiment, the saturation characteristic analysis module specifically includes a data acquisition unit and a saturation characteristic analysis unit;

[0037] The data acquisition unit is used to acquire the LED port voltage and the operating parameters of the flyback converter, and to acquire the corresponding LED port voltage peak value based on the LED port voltage; wherein the operating parameters of the flyback converter include the flyback converter duty cycle, switching frequency, and the primary side static inductance of the transformer;

[0038] The saturation characteristic analysis unit is used to perform inductance saturation characteristic analysis on the LED driver power supply structure using the peak voltage of the LED port and the operating parameters of the flyback converter, so as to obtain the saturation characteristics of the primary inductance of the transformer, and to plot the core hysteresis curve of the primary inductance of the transformer, and to obtain the flux sequence and the current sequence of the primary inductance of the transformer based on the core hysteresis curve.

[0039] As a preferred embodiment, the uncontrolled rectifier circuit includes a first rectifier diode, a second rectifier diode, a third rectifier diode, and a fourth rectifier diode;

[0040] In this configuration, the cathode of the first rectifier diode is connected to the cathode of the third rectifier diode, the anode of the third rectifier diode is connected to the cathode of the fourth rectifier diode, the anode of the fourth rectifier diode is connected to the anode of the second rectifier diode, the cathode of the second rectifier diode is connected to the anode of the first rectifier diode, the anode of the first rectifier diode is connected to the first terminal of the output side of the mains voltage, the second terminal of the output side of the mains voltage is connected to the anode of the third rectifier diode, the cathode of the third rectifier diode is connected to the first terminal of the primary winding of the transformer, and the anode of the fourth rectifier diode is connected to the second terminal of the primary winding of the transformer via a switching transistor.

[0041] As a preferred embodiment, the LC filter circuit includes an output capacitor and an output inductor;

[0042] Wherein, the first end of the output capacitor is connected to the first end of the output inductor, the first end of the output capacitor is connected to the first end of the flyback winding of the transformer via a flyback diode, the second end of the flyback winding of the transformer is connected to the second end of the output inductor, the second end of the output inductor is connected to the anode of the LED, and the cathode of the LED is connected to the second end of the output capacitor. Attached Figure Description

[0043] Figure 1 This is a flowchart illustrating a method for optimizing the structure of an LED driver power supply based on current harmonics, provided in Embodiment 1 of the present invention.

[0044] Figure 2 : A schematic diagram of the LED driver power supply structure provided in Embodiment 1 of the present invention;

[0045] Figure 3 : This is a core hysteresis curve of the primary inductance of the transformer provided in Embodiment 1 of the present invention;

[0046] Figure 4: A schematic diagram of the grid-connected current waveform and its frequency components when the flyback converter is saturated according to theoretical calculations provided in Embodiment 1 of the present invention;

[0047] Figure 5 : A schematic diagram of the grid-side voltage and current waveforms and their frequency components when the flyback converter is saturated during simulation verification provided in Embodiment 1 of the present invention;

[0048] Figure 6 This is a schematic diagram of an LED driver power supply structure optimization system based on current harmonics, provided in Embodiment 1 of the present invention. Detailed Implementation

[0049] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0050] Example 1:

[0051] Please refer to Figure 1 This invention provides an LED driver power supply structure optimization method based on current harmonics. The method includes steps S1 to S3, each step of which is as follows:

[0052] Step S1: Based on the LED port voltage and the operating parameters of the flyback converter, perform inductance saturation characteristic analysis on the LED driver power supply structure to obtain the flux sequence and current sequence of the primary inductance of the transformer.

[0053] For the preferred option, please refer to Figure 2 The LED driver power supply structure consists of an uncontrolled rectifier circuit, a flyback converter, and an LC filter circuit. The flyback converter is composed of a transformer.

[0054] The uncontrolled rectifier circuit includes a first rectifier diode D1, a second rectifier diode D2, a third rectifier diode D3, and a fourth rectifier diode D4. The cathode of the first rectifier diode D1 is connected to the cathode of the third rectifier diode D3; the anode of the third rectifier diode D3 is connected to the cathode of the fourth rectifier diode D4; the anode of the fourth rectifier diode D4 is connected to the anode of the second rectifier diode D2; the cathode of the second rectifier diode D2 is connected to the anode of the first rectifier diode D1; the anode of the first rectifier diode D1 is connected to the first terminal of the mains voltage output side; the second terminal of the mains voltage output side is connected to the anode of the third rectifier diode D3; the cathode of the third rectifier diode D3 is connected to the first terminal of the primary winding of the transformer T; and the anode of the fourth rectifier diode D4 is connected to the second terminal of the primary winding of the transformer T via a switching transistor V.

[0055] The LC filter circuit includes an output capacitor. and output inductor Among them, the output capacitor The first terminal and the output inductor The first terminal is connected to the output capacitor. The first terminal is connected to the first terminal of the flyback winding of transformer T via a flyback diode, and the second terminal of the flyback winding of transformer T is connected to the output inductor. The second terminal is connected to the output inductor. The second terminal is connected to the anode of the LED, and the cathode of the LED is connected to the output capacitor. The second end is connected.

[0056] As a preferred embodiment, step S1 includes steps S11 to S13, and the specific details of each step are as follows:

[0057] Step S11: Obtain the LED port voltage The operating parameters of the flyback converter, and based on the LED port voltage. The corresponding LED port voltage peak value was collected. The operating parameters of the flyback converter include its duty cycle. Switching frequency and the static inductance of the primary side of transformer T .

[0058] Step S12, please refer to equation (1), using the peak voltage of the LED port. Based on the operating parameters of the flyback converter, the peak value of the primary inductor current of transformer T is calculated. .

[0059] （1）

[0060] in, This refers to the LED port voltage frequency.

[0061] Step S13, based on the peak value of the primary inductor current of transformer T. An inductor saturation characteristic analysis was performed on the LED driver power supply structure to obtain the saturation characteristics of the primary inductance of transformer T, and a reference diagram was plotted. Figure 3 The magnetic core hysteresis curve of the primary inductance of transformer T is obtained, and based on the magnetic core hysteresis curve, the flux sequence of the primary inductance of transformer T is obtained. and current sequence .

[0062] In this embodiment, before performing step S2, the peak voltage of the LED port is determined... and LED port voltage frequency Please refer to Equation (2) for the flux-time expression of the primary inductance of transformer T.

[0063] （2）

[0064] Step S2: Iterate through each moment in the flux-time expression of the primary inductance of transformer T. Using the min function, find the sequence number of the flux that is closest to the flux in the flux-time expression at the current iteration moment in the flux sequence. Use this sequence number as the sequence number corresponding to the current iteration moment. Also, obtain the current value corresponding to each sequence number in the current sequence to form the time sequence of the current expression.

[0065] As an example, please refer to equation (3) for the first moment. The magnetic flux sequence was searched to find the expression for magnetic flux time. magnetic flux at time closest magnetic flux And with the sequence number of the magnetic flux As the sequence number corresponding to the time Then according to the serial number The sequence number can be obtained by searching in the current sequence. The corresponding current value, as Current value at time And so on, to obtain all times. The current values ​​are used to construct the time series of the current expression. Thus, a reference is drawn. Figure 4 (a) The theoretical calculation of the grid-connected current waveform when the flyback converter transformer is saturated, and reference Figure 4 (b) Schematic diagram of the frequency components of the grid-connected current waveform when the flyback converter transformer is saturated according to theoretical calculations.

[0066] （3）

[0067] in, This represents the sequence number that takes the minimum value in the sequence. This indicates taking the absolute value.

[0068] Step S3: Calculate the corresponding LED port current harmonics according to the preset harmonic component algorithm and the time series of the current expression, and optimize the LED driver power supply structure based on the LED port current harmonics.

[0069] As a preferred embodiment, step S3 includes steps S31 to S32, each of which is detailed below:

[0070] Step S31: Construct a first time series based on each moment in the flux-time expression of the primary inductance of transformer T. And combined with the first time series and the time series of current expressions The corresponding multiple harmonic components of the LED port current are calculated to form the LED port current harmonics.

[0071] Among them, the LED port current of the first Please refer to equation (4) for the expression of the subharmonic component.

[0072] （4）

[0073] In the formula: This refers to the first moment in the first time series. This refers to the last moment in the first time series. For the first time series At that moment, The first time series of the current expression A current value For harmonic order, This refers to the LED port voltage frequency.

[0074] Step S32: Optimize the LED driver power supply structure based on the LED port current harmonics.

[0075] In this embodiment, please refer to Figure 1 Construct a simulation circuit diagram, and consider the presence of primary-side inductance of the transformer as a reference. Figure 3 The saturation characteristics were observed during the simulation verification process, and harmonic analysis was performed to obtain a reference. Figure 5(a) Simulation verification of the grid-connected voltage and grid-connected current waveforms when the flyback converter transformer is saturated, and reference... Figure 5 (b) Schematic diagram of the frequency components of the grid-connected voltage and grid current when the flyback converter transformer is saturated during simulation verification.

[0076] Please refer to Figure 6 This is a schematic diagram of a structure optimization system for an LED driver power supply based on current harmonics, provided by an embodiment of the present invention. The system includes a saturation characteristic analysis module M1, a sequence construction module M2, and a structure optimization module M3, the specific details of which are as follows:

[0077] The saturation characteristic analysis module M1 is used to perform inductance saturation characteristic analysis on the LED driver power supply structure based on the LED port voltage and the operating parameters of the flyback converter, so as to obtain the flux sequence and current sequence of the primary inductance of the transformer. The LED driver power supply structure consists of an uncontrolled rectifier circuit, a flyback converter and an LC filter circuit. The flyback converter is composed of a transformer.

[0078] The sequence construction module M2 is used to traverse each moment in the flux-time expression of the primary inductance of the transformer. Through the min function, it queries the flux sequence to obtain the sequence number corresponding to the current traversal moment, and obtains the current value corresponding to each sequence number in the current sequence to form the time sequence of the current expression.

[0079] The structure optimization module M3 is used to calculate the corresponding LED port current harmonics according to the preset harmonic component algorithm and the time series of the current expression, and to optimize the LED driver power supply structure based on the LED port current harmonics.

[0080] As a preferred embodiment, the structural optimization module M3 specifically includes a harmonic component calculation unit 31 and a structural optimization unit 32, the details of which are as follows:

[0081] The harmonic component calculation unit is used to construct a first time series based on each moment in the flux-time expression of the primary inductance of the transformer, and combine the first time series with the time series of the current expression to calculate the corresponding multiple harmonic components of the LED port current, thus constituting the LED port current harmonics; wherein, the first harmonic component of the LED port current is... The expression for the subharmonic component is as follows:

[0082]

[0083] In the formula: This refers to the first moment in the first time series. This refers to the last moment in the first time series. For the first time series At that moment, The first time series of the current expression A current value For harmonic order, The LED port voltage frequency;

[0084] The structure optimization unit is used to optimize the LED driver power supply structure based on the harmonics of the LED port current.

[0085] As a preferred embodiment, the saturation characteristic analysis module M1 specifically includes a data acquisition unit 11 and a saturation characteristic analysis unit 12, the details of which are as follows:

[0086] The data acquisition unit 11 is used to acquire the LED port voltage and the operating parameters of the flyback converter, and to acquire the corresponding LED port voltage peak value based on the LED port voltage; wherein, the operating parameters of the flyback converter include the flyback converter duty cycle, switching frequency, and the primary side static inductance of the transformer.

[0087] The saturation characteristic analysis unit 12 is used to perform inductance saturation characteristic analysis on the LED driver power supply structure using the LED port voltage peak and the operating parameters of the flyback converter, so as to obtain the saturation characteristics of the primary side inductance of the transformer, and to plot the magnetic core hysteresis curve of the primary side inductance of the transformer. Based on the magnetic core hysteresis curve, the flux sequence and current sequence of the primary side inductance of the transformer are obtained.

[0088] As a preferred embodiment, the uncontrolled rectifier circuit in the LED driver power supply structure includes a first rectifier diode, a second rectifier diode, a third rectifier diode, and a fourth rectifier diode; wherein, the cathode of the first rectifier diode is connected to the cathode of the third rectifier diode, the anode of the third rectifier diode is connected to the cathode of the fourth rectifier diode, the anode of the fourth rectifier diode is connected to the anode of the second rectifier diode, the cathode of the second rectifier diode is connected to the anode of the first rectifier diode, the anode of the first rectifier diode is connected to the first terminal of the output side of the mains voltage, the second terminal of the output side of the mains voltage is connected to the anode of the third rectifier diode, the cathode of the third rectifier diode is connected to the first terminal of the primary winding of the transformer, and the anode of the fourth rectifier diode is connected to the second terminal of the primary winding of the transformer via a switching transistor.

[0089] As a preferred embodiment, the LC filter circuit in the LED driver power supply structure includes an output capacitor and an output inductor; wherein, the first end of the output capacitor is connected to the first end of the output inductor, the first end of the output capacitor is connected to the first end of the flyback winding of the transformer through a flyback diode, the second end of the flyback winding of the transformer is connected to the second end of the output inductor, the second end of the output inductor is connected to the anode of the LED, and the cathode of the LED is connected to the second end of the output capacitor.

[0090] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working process of the system described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0091] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0092] This invention provides a method and system for optimizing the structure of an LED driver power supply based on current harmonics. Based on the LED port voltage and the operating parameters of the flyback converter, the inductor saturation characteristics of the LED driver power supply structure are analyzed. Using the flux sequence and current sequence of the primary inductor of the transformer obtained from the analysis, the LED port current harmonics are derived and calculated. This fully considers the current harmonic problem caused by the saturation of the flyback converter transformer due to extreme LED component parameters. Then, based on the calculated LED port current harmonics, the LED driver power supply structure is optimized to further improve the performance of the power grid system, reduce excessive losses on LED components, and overcome the limitation on the lifespan of LED components caused by extreme LED component parameters.

[0093] Furthermore, by utilizing the unidirectional conductivity of multiple rectifier diodes in the uncontrolled rectifier circuit, the AC voltage provided by the power grid system is converted into DC voltage, thereby rectifying the voltage signal output from the power grid output side and providing a stable DC voltage signal for the flyback converter. In addition, the LC filter circuit composed of the output capacitor and output inductor smooths the waveform of the LED port current, thus optimizing the performance of the LED driver power supply structure.

[0094] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. In particular, it should be noted that any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention for those skilled in the art.

Claims

1. A method for optimizing the structure of an LED driver power supply based on current harmonics, characterized in that, include: Step S1: Based on the LED port voltage and the operating parameters of the flyback converter, perform inductance saturation characteristic analysis on the LED driver power supply structure to obtain the flux sequence and current sequence of the primary inductance of the transformer; wherein, the LED driver power supply structure consists of an uncontrolled rectifier circuit, the flyback converter, and an LC filter circuit, and the flyback converter is composed of the transformer; Step S11: Obtain the LED port voltage The operating parameters of the flyback converter, and based on the LED port voltage. The corresponding LED port voltage peak value was collected. The operating parameters of the flyback converter include its duty cycle. Switching frequency and the static inductance of the primary side of the transformer. ; Step S12, using the peak voltage of the LED port Based on the operating parameters of the flyback converter, the peak value of the primary inductor current of the transformer is calculated. : ； in, The LED port voltage frequency; Step S13, based on the peak value of the primary inductor current of the transformer. The inductor saturation characteristics of the LED driver power supply structure are analyzed to obtain the saturation characteristics of the primary inductor of the transformer. The core hysteresis curve of the primary inductor of the transformer is plotted, and the magnetic flux sequence of the primary inductor of the transformer is obtained based on the core hysteresis curve. and current sequence ; Step S14, based on the peak voltage of the LED port and LED port voltage frequency Obtain the flux-time expression for the primary inductance of the transformer; ； Step S2: Iterate through each moment in the flux-time expression of the primary inductance of the transformer, use the min function to query the sequence number corresponding to the current iteration moment in the flux sequence, and obtain the current value corresponding to each sequence number in the current sequence to form the time sequence of the current expression. For the first moment The magnetic flux sequence was searched to find the expression for magnetic flux time. magnetic flux at time closest magnetic flux And with the sequence number of the magnetic flux As the sequence number corresponding to the time Then according to the serial number The sequence number can be obtained by searching in the current sequence. The corresponding current value, as Current value at time Get all times The current values ​​are used to construct the time series of the current expression. ,in, ; Step S3: Calculate the corresponding LED port current harmonics according to the preset harmonic component algorithm and the time series of the current expression, and optimize the LED driver power supply structure based on the LED port current harmonics. The calculation yields the corresponding LED port current harmonics, specifically: Based on each moment in the flux-time expression of the primary inductance of the transformer, a first time series is constructed, and by combining the first time series and the time series of the current expression, the multiple harmonic components of the corresponding LED port current are calculated to constitute the LED port current harmonics. Among them, the LED port current of the first The expression for the subharmonic component is as follows: ； In the formula: This refers to the first moment in the first time series. This refers to the last moment in the first time series. For the first time series, the first At that moment, The time series of the current expression is the first... A current value This represents the harmonic order.

2. The LED driver power supply structure optimization method based on current harmonics as described in claim 1, characterized in that, The uncontrolled rectifier circuit includes a first rectifier diode, a second rectifier diode, a third rectifier diode, and a fourth rectifier diode; In this configuration, the cathode of the first rectifier diode is connected to the cathode of the third rectifier diode, the anode of the third rectifier diode is connected to the cathode of the fourth rectifier diode, the anode of the fourth rectifier diode is connected to the anode of the second rectifier diode, the cathode of the second rectifier diode is connected to the anode of the first rectifier diode, the anode of the first rectifier diode is connected to the first terminal of the output side of the mains voltage, the second terminal of the output side of the mains voltage is connected to the anode of the third rectifier diode, the cathode of the third rectifier diode is connected to the first terminal of the primary winding of the transformer, and the anode of the fourth rectifier diode is connected to the second terminal of the primary winding of the transformer via a switching transistor.

3. The LED driver power supply structure optimization method based on current harmonics as described in claim 1, characterized in that, The LC filter circuit includes an output capacitor and an output inductor; Wherein, the first end of the output capacitor is connected to the first end of the output inductor, the first end of the output capacitor is connected to the first end of the flyback winding of the transformer via a flyback diode, the second end of the flyback winding of the transformer is connected to the second end of the output inductor, the second end of the output inductor is connected to the anode of the LED, and the cathode of the LED is connected to the second end of the output capacitor.

4. A system for optimizing the structure of an LED driver power supply based on current harmonics, characterized in that, include: The saturation characteristic analysis module is used to perform inductance saturation characteristic analysis on the LED driver power supply structure based on the LED port voltage and the operating parameters of the flyback converter, so as to obtain the flux sequence and current sequence of the primary inductance of the transformer; wherein, the LED driver power supply structure consists of an uncontrolled rectifier circuit, the flyback converter and an LC filter circuit, and the flyback converter is composed of the transformer; The saturation characteristic analysis module includes steps S11 to S14, each step of which is as follows: Step S11: Obtain the LED port voltage The operating parameters of the flyback converter, and based on the LED port voltage. The corresponding LED port voltage peak value was collected. The operating parameters of the flyback converter include its duty cycle. Switching frequency and the static inductance of the primary side of the transformer. ; Step S12, using the peak voltage of the LED port Based on the operating parameters of the flyback converter, the peak value of the primary inductor current of the transformer is calculated. : ； in, The LED port voltage frequency; Step S13, based on the peak value of the primary inductor current of the transformer. The inductor saturation characteristics of the LED driver power supply structure are analyzed to obtain the saturation characteristics of the primary inductor of the transformer. The core hysteresis curve of the primary inductor of the transformer is plotted, and the magnetic flux sequence of the primary inductor of the transformer is obtained based on the core hysteresis curve. and current sequence ; Step S14, based on the peak voltage of the LED port and LED port voltage frequency Obtain the flux-time expression for the primary inductance of the transformer; ； The sequence construction module is used to traverse each moment in the flux-time expression of the primary inductance of the transformer, and use the min function to query the sequence number corresponding to the current traversal moment in the flux sequence, and obtain the current value corresponding to each sequence number in the current sequence to form the time sequence of the current expression. For the first moment The magnetic flux sequence was searched to find the expression for magnetic flux time. magnetic flux at time closest magnetic flux And with the sequence number of the magnetic flux As the sequence number corresponding to the time Then according to the serial number The sequence number can be obtained by searching in the current sequence. The corresponding current value, as Current value at time Get all times The current values ​​are used to construct the time series of the current expression. ,in, ; The structure optimization module is used to calculate the corresponding LED port current harmonics according to a preset harmonic component algorithm and the time series of the current expression, and to optimize the LED driver power supply structure based on the LED port current harmonics. The structure optimization module specifically includes a harmonic component calculation unit and a structure optimization unit; The harmonic component calculation unit is used to construct a first time sequence based on each moment in the flux time expression of the primary inductance of the transformer, and to calculate the multiple harmonic components of the corresponding LED port current by combining the first time sequence and the time sequence of the current expression, so as to constitute the LED port current harmonics. Among them, the LED port current of the first The expression for the subharmonic component is as follows: ； In the formula: This refers to the first moment in the first time series. This refers to the last moment in the first time series. For the first time series, the first At that moment, The time series of the current expression is the first... A current value For harmonic order; The structure optimization unit is used to optimize the LED driver power supply structure based on the harmonics of the LED port current.

5. The LED driver power supply structure optimization system based on current harmonics as described in claim 4, characterized in that, The uncontrolled rectifier circuit includes a first rectifier diode, a second rectifier diode, a third rectifier diode, and a fourth rectifier diode; In this configuration, the cathode of the first rectifier diode is connected to the cathode of the third rectifier diode, the anode of the third rectifier diode is connected to the cathode of the fourth rectifier diode, the anode of the fourth rectifier diode is connected to the anode of the second rectifier diode, the cathode of the second rectifier diode is connected to the anode of the first rectifier diode, the anode of the first rectifier diode is connected to the first terminal of the output side of the mains voltage, the second terminal of the output side of the mains voltage is connected to the anode of the third rectifier diode, the cathode of the third rectifier diode is connected to the first terminal of the primary winding of the transformer, and the anode of the fourth rectifier diode is connected to the second terminal of the primary winding of the transformer via a switching transistor.

6. The LED driver power supply structure optimization system based on current harmonics as described in claim 4, characterized in that, The LC filter circuit includes an output capacitor and an output inductor; Wherein, the first end of the output capacitor is connected to the first end of the output inductor, the first end of the output capacitor is connected to the first end of the flyback winding of the transformer via a flyback diode, the second end of the flyback winding of the transformer is connected to the second end of the output inductor, the second end of the output inductor is connected to the anode of the LED, and the cathode of the LED is connected to the second end of the output capacitor.

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