Power control method, driving device, LED driving power supply and lighting device

Abstract

The invention relates to a power control method, a driving device, an LED driving power supply and a lighting device.The power control method comprises the steps that after power-on starting, a second current reference is generated according to a first current reference; generating a second driving current according to the second current reference, and driving the load to work through the second driving current; acquiring a real-time voltage sampling signal; calculating according to the real-time voltage sampling signal to obtain an expected current corresponding to the expected power; forming a control quantity based on the expected current and the preset current; and the power conversion circuit is adjusted according to the control quantity to realize closed-loop control of the load output power. According to the invention, automatic adaptation to loads of different specifications is realized through critical working mode detection, the coupling problem of a double-loop feedback scheme is effectively avoided by adopting a mode of combining single-loop current control with reference judgment, the problem that a voltage limiting type power control scheme cannot be driven when the working voltage required by the load is relatively high is solved, power control is realized, and the working efficiency is improved. Stability and reliability are significantly improved, and load life is prolonged.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of LED power supply control, more particularly, to a power control method, a driving device, an LED driving power supply and a lighting device. BACKGROUND

[0002] The existing LED driving power supply mostly adopts constant current control mode, that is, maintaining constant current in the whole output range. However, in different power LED module applications, there are the following problems: when the LED load changes (different modules, aging, temperature rise causes LED lamp beads The constant current scheme of the LED driving power supply is prone to exceed the designed power output.

[0003] Therefore, the LED power supply needs to control not only the current but also the output power.

[0004] The existing power control scheme is generally as follows: 1) Double-loop feedback scheme: a voltage loop is added outside the current loop, and the voltage loop and the current loop dynamically adjust the output voltage and current to achieve constant power output. However, this scheme has the problems of cross-coupling of loop gain / phase, complex loop coupling, poor stability, slow dynamic response, narrow design window, etc.

[0005] 2) Voltage limiting power control scheme: the maximum output voltage is calculated by presetting the current value and the expected power to achieve voltage limiting of a fixed value. When the working voltage required by the LED module exceeds the voltage limit value, the maximum output voltage is limited by the voltage loop, and the LED module directly stops working.

[0006] Therefore, the existing power control scheme still has certain defects in stability, adaptability and implementation complexity. SUMMARY

[0007] The technical problem to be solved by the present application is to provide a power control method, a driving device, an LED driving power supply and a lighting device in view of the problems in the prior art.

[0008] The technical scheme adopted by the present application to solve the technical problem is: a power control method, comprising the following steps: After power-on starting, a second current reference is generated according to a first current reference; A second driving current is generated according to the second current reference, and the load is driven to work through the second driving current, so that the load is in a critical working state; The actual working voltage of the load is collected to obtain a real-time voltage sampling signal; The expected current corresponding to the expected power is obtained by calculating according to the real-time voltage sampling signal; A control quantity is formed based on the expected current and the preset current; The power conversion circuit is adjusted according to the control quantity to achieve closed-loop control of the load output power.

[0009] In the power control method of the present invention, generating a second current reference based on a first current reference includes: The control unit invokes the first current reference and outputs a second current reference control signal based on the first current reference; The current reference circuit generates the second current reference based on the second current reference control signal.

[0010] In the power control method of the present invention, generating the second drive current according to the second current reference includes: The current regulation unit performs a comparison and calculation based on the second current reference and the current sampling signal to obtain a first error signal; The power conversion circuit is controlled by the first error signal to perform closed-loop control in order to output the second drive current.

[0011] In the power control method of the present invention, the step of acquiring the actual operating voltage of the load and obtaining a real-time voltage sampling signal includes: After the load starts working, the voltage sampling circuit samples the actual operating voltage of the load to obtain the real-time voltage sampling signal.

[0012] In the power control method of the present invention, the step of calculating the expected current based on the real-time voltage sampling signal includes: The control unit acquires the expected power; The control unit calculates the expected current based on the expected power and the real-time voltage sampling signal.

[0013] In the power control method of the present invention, the step of forming a control quantity based on the expected current and the preset current includes: The expected current is compared with the preset current to determine the result; If the expected current is greater than or equal to the preset current, the preset current is selected as the control quantity. If the expected current is less than the preset current, the expected current is selected as the control quantity.

[0014] In the power control method of the present invention, the step of adjusting the power conversion circuit according to the control quantity to achieve closed-loop control of the load output power includes: The control unit outputs a third current reference control signal according to the control quantity; The current reference circuit generates a third current reference based on the third current reference control signal; The current regulation unit performs a comparison and calculation based on the third current reference and the current sampling signal to obtain a second error signal; The power conversion circuit is controlled by the second error signal to perform closed-loop control in order to output the third drive current; The load is driven to operate by the third driving current; The current sampling circuit performs real-time current sampling during the operation of the load to obtain the real-time current signal of the load, and feeds the real-time current signal back to the current regulation unit; The current regulation unit adjusts the third drive current based on the real-time current signal, so that the third drive current supplies power to the load in a constant current mode.

[0015] The present invention also provides a driving device, comprising: a control unit, a current loop, a voltage loop, and a power conversion circuit; The control unit is used to generate a second current reference control signal based on a first current reference after the power supply is powered on and started, and to calculate the expected current corresponding to the expected power based on the real-time voltage sampling signal collected by the voltage loop, and to form a control quantity based on the expected current and the preset current. The current loop generates a second current reference based on the second current reference control signal, and generates a second drive current based on the second current reference, so as to drive the load to work through the second drive current, so that the load is in a critical working state. The voltage loop acquires the actual operating voltage of the load to obtain the real-time voltage acquisition signal; The power conversion circuit achieves closed-loop control of the load output power by adjusting the control quantity.

[0016] The present invention also provides an LED driver power supply, including the driving device described above.

[0017] The present invention also provides a lighting device, including the LED driver power supply described above.

[0018] The power control method, driving device, LED driver power supply, and lighting device of the present invention have the following beneficial effects: The power control method includes the following steps: after power-on startup, a second current reference is generated based on a first current reference; a second driving current is generated based on the second current reference, and the load is driven to work through the second driving current; a real-time voltage sampling signal is acquired; a expected current corresponding to the expected power is calculated based on the real-time voltage sampling signal; a control quantity is formed based on the expected current and a preset current; and the power conversion circuit is adjusted according to the control quantity to achieve closed-loop control of the load output power. The present invention achieves automatic adaptation to loads of different specifications through critical operating mode detection, and adopts a single-loop current control combined with reference adjudication, effectively avoiding the coupling problem of the dual-loop feedback scheme, solving the problem that voltage-limited power control schemes cannot drive the load when the required operating voltage is high, achieving power control, significantly improving stability and reliability, and extending load life. Attached Figure Description

[0019] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings: Figure 1 This is a schematic flowchart of the power control method provided in an embodiment of the present invention; Figure 2 This is a schematic block diagram of the power control device provided in an embodiment of the present invention; Figure 3 This is a circuit diagram of the first current reference circuit provided in an embodiment of the present invention; Figure 4 This is a circuit diagram of the current calculation circuit and the current compensation circuit provided in the embodiments of the present invention; Figure 5 and Figure 6 This is a circuit diagram of the voltage sampling circuit, voltage calculation circuit, voltage compensation circuit, and analog OR gate provided in the embodiments of the present invention; Figure 7 This is a circuit diagram of the power conversion circuit provided in an embodiment of the present invention; Figure 8 This is a circuit diagram of the current sampling circuit provided in an embodiment of the present invention. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. In the present invention, the reference refers to the target value state set by the control system, and the sampling is used to characterize the actual value state acquired by the control system. Both can be characterized by actual physical quantities or equivalent quantities that correspond to the physical quantities. 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.

[0021] To address the problems existing in current power control schemes, this invention provides a power control method that can achieve adaptive power drive for different loads (such as LED modules), effectively overcoming the shortcomings of traditional constant current methods, dual-loop feedback schemes, and voltage-limited power control schemes, and significantly improving system stability and reliability.

[0022] Specifically, in a preferred embodiment, such as Figure 1 As shown, the power control method includes the following steps: Step S10: After power-on startup, generate a second current reference based on the first current reference.

[0023] Optionally, in this step, generating the second current reference based on the first current reference includes: the control unit calling the first current reference; and outputting a second current reference control signal based on the first current reference; the current reference circuit generating the second current reference based on the second current reference control signal. The control unit calling the first current reference includes: reading a preset first current reference from a storage unit, or receiving an externally set first current reference through an external communication interface and storing it in the storage unit. The second current control signal is generated by the control unit based on the first current reference and output as a PWM waveform or an equivalent analog control voltage to instruct the current reference circuit to generate the second current reference.

[0024] Specifically, before leaving the factory or achieving a specific output current target, the control unit retrieves a first current reference stored in a memory cell either inside or outside the control unit. This first current reference is defined as I. ref Because the preset current I has been determined at the factory or before achieving a specific output current target. rated Generate I ref Therefore, after the LED power supply is powered on, the control unit can directly call this I. ref And according to the I refA corresponding current control signal (i.e., a second current reference control signal) is generated, and then the current reference circuit generates a corresponding second current reference based on this second current reference control signal. This second current reference can be defined as I. 1ref The current reference circuit is mainly used to obtain I after performing integration and filtering processing on the second current reference control signal. 1ref The current reference circuit processes the second current reference control signal. When the second current reference control signal is output in PWM form, it is smoothed into a DC voltage after integration and filtering. When the current control signal is a DC voltage signal, it can be filtered and used as the second current reference I. 1ref .

[0025] Step S20: Generate a second driving current based on the second current reference, and drive the load to work through the second driving current, so that the load is in a critical working state. The load is in a critical working state, which means that the LED is forward biased and the applied voltage exceeds its specific turn-on voltage. In this step, a current value much smaller than the normal working current of the LED can be selected as the critical working current. For example, 1% or 2% of the preset current can be selected as the critical working current to drive the LED.

[0026] In this step, generating a second drive current based on a second current reference and driving the load to work through the second drive current includes: the current regulation unit comparing and calculating the second current reference and the current sampling signal to obtain a first error signal; and controlling the power conversion circuit to perform closed-loop control through the first error signal to output the second drive current.

[0027] In this embodiment of the invention, the current reference circuit generates a second current reference I. 1ref Then, the current regulating unit will adjust the second current reference I. 1ref A first error signal is obtained by comparing and calculating with the current sampling signal. This first error signal is then used to control the power conversion circuit in a closed-loop manner to drive the second drive current. This second drive current can be expressed as I... dete Indicated; wherein, the second drive current I dete It is the current used to detect the operating voltage of the load (i.e., the LED module), I 1ref : I ref =: I dete :I rated , and I 1ref < ref .

[0028] Step S30: Collect the actual operating voltage of the load to obtain a real-time voltage sampling signal.

[0029] ​Optionally, in this step, acquiring the actual operating voltage of the load and obtaining the real-time voltage sampling signal includes: after the load starts working, the voltage sampling circuit samples the actual operating voltage of the load to obtain the real-time voltage sampling signal. Specifically, when the second drive current I... dete After the LED module is lit, it begins to work. Based on the LED's voltage-current characteristics, the power supply's output voltage (V) at this time is... o The voltage V is equal to the operating voltage of the LED module. lite Due to the current-voltage characteristics of LEDs, there is a one-to-one correspondence between current and voltage within the normal operating range, and the voltage changes only slightly with the current. Therefore, the voltage of the LED module in the critical operating mode can be used to approximately characterize the actual operating current state and the maximum operating voltage of the LED module. Based on this principle, in the present invention, when the second driving current I... dete After the LED module is lit, the actual operating voltage of the LED module is sampled by the voltage sampling circuit to obtain the corresponding real-time voltage sampling signal. Then, the real-time voltage sampling signal is used to prepare for the power control scheme of single-loop current + reference decision.

[0030] Step S40: Calculate the expected current corresponding to the expected power based on the real-time voltage sampling signal. In this embodiment of the invention, the expected current is used as a reference for current determination under different load voltage conditions, realizing power adaptation, current limiting protection, and constant power output characteristics.

[0031] Optionally, in this step, calculating the expected current corresponding to the expected power based on the real-time voltage sampling signal includes: the control unit acquiring the expected power; and the control unit calculating the expected current based on the expected power and the real-time voltage sampling signal. Specifically, in this embodiment of the invention, the operating voltage of the LED module in the critical operating mode state (i.e., the real-time voltage sampling signal V) is sampled by the voltage sampling circuit. lite After that, the control unit calculates the expected maximum output current, i.e., the expected current, based on the expected power and the real-time voltage sampling signal. This expected current is defined as I. exp Among them, the expected current I exp It can be calculated using the following formula: I exp =P target / V lite (1); In the above formula, I exp For the expected current, P target For the expected power, V lite This refers to the operating voltage of the LED module in its critical operating mode. The expected power P is... targetThis is the current target output power setting for the LED driver power supply, used for power adaptive calculation and output power constraints. Expected power P target The value is the effective power data adjusted by dimming control or external control commands, and can dynamically change according to different control methods. Its initial value can be stored in a non-volatile, erasable, and rewritable memory unit at the factory. Specifically, P target The power setting can be obtained through the following methods: the factory-preset rated power or the power after dimming control; real-time power setting data generated after user adjustment via external interfaces (such as DALI, NFC, 485 communication, or dimming control signals); and the power setting value automatically corrected by the control unit based on energy-saving operation, temperature protection, or system strategies. Among these, P... targe The value of t should not exceed the maximum output power of the LED driver within the design range.

[0032] Step S50: Generate a control quantity based on the expected current and the preset current.

[0033] Optionally, in this step, forming a control quantity based on the expected current and the preset current includes: comparing the expected current with the preset current; if the expected current is greater than or equal to the preset current, selecting the preset current as the control quantity; if the expected current is less than the preset current, selecting the expected current as the control quantity.

[0034] Specifically, after calculating the expected current in step S40, the expected current is first compared with the first drive current, and then power control is performed based on the comparison result. This is divided into the following two cases: First scenario: Expected current I exp Greater than or equal to the preset current I rated Specifically: when I exp ≥I rated At that time, the preset current I will be used. rated As a control quantity; Second scenario: Expected current I exp Less than the preset current I rated Specifically: when I exp <I rated At that time, the preset current I will be used. rated As a control variable.

[0035] Step S60: Adjust the power conversion circuit according to the control quantity to achieve closed-loop control of the load output power.

[0036] Optionally, adjusting the power conversion circuit according to the control quantity to achieve closed-loop control of the load output power includes: the control unit outputting a third current reference control signal according to the control quantity; the current reference circuit generating a third current reference according to the third current reference control signal; the current adjustment unit comparing and calculating the third current reference and the current sampling signal to obtain a second error signal; controlling the power conversion circuit to perform closed-loop control through the second error signal to output a third drive current; driving the load to work through the third drive current; the current sampling circuit performing real-time current sampling during load operation to obtain the real-time current signal of the load and feeding the real-time current signal back to the current adjustment unit; the current adjustment unit adjusting the third drive current based on the real-time current signal to supply power to the load in a constant current mode.

[0037] Specifically, if the expected current I exp Greater than or equal to the preset current I rated Then based on the preset current I rated The power conversion circuit is adjusted to achieve closed-loop control of the load output power. Specifically, the control unit adjusts the power output based on a preset current I. rated The third current reference control signal is output. At this time, the current reference circuit performs comparison calculations based on the third current reference control signal to obtain the second error signal. Then, the second error signal is used to control the power conversion circuit to perform closed-loop control, so as to output the third drive current. The load is driven to work through the third drive current. At this time, the real-time current is sampled in real time during the operation of the load by the current sampling circuit to obtain the real-time current signal of the load. The real-time current signal is fed back to the current regulation unit. The current regulation unit adjusts the third drive current based on the real-time current signal, so that the third drive current supplies power to the load in a constant current mode.

[0038] Specifically, if the expected current I exp Less than the preset current I rated Then based on the expected current I exp The power conversion circuit is adjusted to achieve closed-loop control of the load output power. Specifically, the control unit adjusts the power output based on the expected current I. expThe third current reference control signal is output. At this time, the current reference circuit performs comparison calculations based on the third current reference control signal to obtain the second error signal. This second error signal is then used to control the power conversion circuit for closed-loop control, outputting the third drive current to drive the load. During load operation, the current sampling circuit can perform real-time current sampling to obtain the load's real-time current signal, which is then fed back to the current regulation unit. The current regulation unit adjusts the third drive current based on this real-time current signal, ensuring it operates in constant current mode to power the load. This results in the actual operating power of the LED module being lower than or equal to the expected power. Furthermore, the output current is automatically adjusted under different load voltage conditions, achieving constant power output outside the constant current output region. This gives the LED driver power supply constant power adaptive control performance. The "constant current output region" refers to the area where the load (LED string) operating voltage is within the power supply's allowable adjustment range (not exceeding the maximum output voltage V). max When the current loop is in operation, it can stabilize the output current at the preset rated value I. rated The output voltage range that remains constant near the target voltage; beyond this range, it can no longer be maintained. rated When the current is constant, it is considered to be outside the "constant current output region".

[0039] Optionally, during the operation of the LED module, since the working voltage of the LED module is affected by factors such as temperature and current, the control unit continuously collects the real-time voltage sampling signal through the voltage sampling circuit, combines it with the target power expected power, and continues to calculate the new current value according to equation (1), thereby obtaining a new second current reference, and updating the value of the second current reference in real time, so as to realize that the working power is equal to the expected power.

[0040] In this embodiment of the invention, the system has preset the maximum output voltage reference value V before the power supply leaves the factory or before actual use. ref This voltage reference is used to limit the maximum output voltage V of the power supply. max During normal operation, the power supply output voltage depends on the load; therefore, the voltage does not participate in power regulation. The maximum output voltage V... max This is used to control the output voltage so that it does not exceed a preset range. The maximum output voltage reference can be achieved in the following two ways: Hardware approach: A fixed voltage reference can be directly generated using a voltage regulator circuit or a resistor divider network; or the reference voltage can be adjusted by adjusting the resistor divider ratio using an external potentiometer.

[0041] Software method: The processor outputs a PWM waveform (V PWMThe voltage is converted into a stable DC reference voltage after passing through an integrating filter circuit. The peak amplitude of the PWM is a fixed value, while the duty cycle directly represents the magnitude of the reference voltage. By modifying the duty cycle parameter in the software, the maximum output voltage reference can be flexibly adjusted to adapt to different application requirements. This voltage reference is written into the system during design or factory shipment, constrained by safety boundary conditions, but can be modified and optimized later through a programmer, NFC, DALI interface, or firmware update.

[0042] The power control method of the present invention has the following advantages compared with existing conventional solutions: Highly adaptable: It automatically adapts to LED modules of different specifications and series numbers by detecting critical operating modes; Precise power control: Single-loop current control + reference decision avoids dual-loop coupling issues; Highly configurable: Both the maximum voltage and preset current can be designed and written, and the interface can be modified later. Improved stability and reliability: Over-driving is avoided through an adjudication mechanism, extending the lifespan of the LED driver power supply; Simplicity of implementation: The current loop performs closed-loop regulation based on the third current reference after the decision. Under the constraints of maximum output voltage and safety boundary, the output power of the LED driver power supply is made to achieve constant power output outside the constant current output region, so that the LED driver power supply has the performance of constant power adaptive control.

[0043] refer to Figure 2 The present invention also provides an LED driver power supply. In a preferred embodiment, such as... Figure 2 As shown, the LED driver power supply includes: a control unit, a current loop, a voltage loop, and a power conversion circuit.

[0044] The control unit is used to generate a second current reference control signal based on a first current reference after the power supply is powered on, and to calculate the expected current corresponding to the expected power based on the real-time voltage sampling signal collected by the voltage loop, and to form a control quantity based on the expected current and the preset current; the current loop generates a second current reference based on the second current reference control signal, and generates a second drive current based on the second current reference, so as to drive the load to work through the second drive current and put the load in a critical working state; the voltage loop collects the actual working voltage of the load and obtains a real-time voltage acquisition signal; the power conversion circuit adjusts the control quantity to realize closed-loop control of the load output power.

[0045] in, Figure 2 The processor in the code is the control unit. The current loop consists of a current reference circuit and a current regulation unit. The current regulation unit consists of a current calculation circuit and a compensation circuit. Figure 2 It consists of a compensation circuit (connected to the current calculation circuit) and a current sampling circuit, specifically as follows:Figure 2 As shown. The voltage loop consists of a voltage reference circuit and a voltage regulation unit. The voltage regulation unit comprises a voltage calculation circuit, a compensation circuit, and a voltage sampling circuit, as detailed below. Figure 2 As shown in the figure. The real-time operating voltage of the load is acquired through a voltage sampling circuit.

[0046] Specifically, the specific coordination and operation process between the various units in the LED driver power supply can be referred to the power control method described above, and will not be repeated here.

[0047] refer to Figures 3-8 This invention provides circuit examples of specific applications of each circuit of the LED driver power supply.

[0048] Specifically, such as Figure 3 As shown, the current reference circuit includes resistors R45 and R46, operational amplifier U4-A, capacitors C26 and C23, resistors R47 and R63. The second current reference control signal IPWM output from the control unit (i.e., the processor) is processed by an integrating and filtering circuit composed of resistors R45 and R46, operational amplifier U4-A, capacitors C26 and C23, and resistors R47 and R63 to generate the second current reference. Figure 4 As shown, the current calculation circuit includes: resistors R65, R66, R67, and R68; comparator U6; capacitor C32; and capacitor C24. The compensation circuit (here, the compensation circuit is the current loop compensation circuit) includes: capacitor C30; capacitor C31; and resistor R70. Figure 3 and Figure 4 As shown, the second current reference generated by the current reference circuit is compared and processed by resistors R65, R66, R67, and R68, comparator U6, capacitor C32, and capacitor C24. After compensation by the current compensation circuit, it flows into the analog OR gate (i.e., the second input terminal of diode D14) through resistor R71. The current sampling signal (IS) obtained by the current sampling circuit is input to comparator U6. Comparator U6 compares and performs calculations based on the second current reference and the current sampling signal, and then outputs the result, realizing closed-loop control of the current loop.

[0049] like Figure 5 As shown and Figure 6As shown, the voltage sampling circuit includes diode D5; the voltage operation circuit includes resistors R53, R54, R55, R110, R10, R106, R108, R48, capacitor C37, resistor R58, and operational amplifier U4-B. The voltage compensation circuit includes resistor R57, capacitor C27, and capacitor C28. The real-time voltage sampling signal (VFB) obtained through isolated output sampling is processed by the voltage operation circuit composed of resistors R53, R54, R55, R110, R10, R10, R106, R108, R48, capacitor C37, resistor R58, and operational amplifier U4-B, and then compensated by the voltage compensation circuit. The signal then flows into the first input terminal of diode D14, and is then coupled and fed back through the optocoupler in the power conversion circuit. Finally, the output of the primary winding T1-A is controlled by chip U2 of the power conversion circuit (e.g., ...). Figure 7 As shown in the diagram, the corresponding operating current is then obtained from the output of the secondary windings T1-C and T1-D. The current sampling circuit uses a power stage main output and isolated output current sampling method for current sampling. Specifically, after the outputs from the secondary windings T1-C and T1-D, the current is rectified by diodes D12 and D13, sampled by winding T2-B, and then isolated and output through winding T2-A to obtain the sampled current (IS). See details below. Figure 8 As shown.

[0050] The present invention also provides a lighting device, wherein the LED driver power supply of the lighting device includes the LED driver power supply disclosed in the embodiments of the present invention.

[0051] The lighting device of the present invention uses the aforementioned power control method for power control, which enables automatic adaptation to LED modules of different specifications and series numbers by detecting critical operating modes. It avoids the problem of dual-loop coupling by using single current control + reference adjudication. At the same time, the maximum voltage and preset current can be designed and written, supporting later interface modifications and high configurability. Through correction and adjudication mechanisms, it avoids overdrive or underdrive, extending the life of LEDs. The control method is simpler: the current loop performs closed-loop adjustment based on the first current reference after adjudication, and under the constraints of maximum output voltage and safety boundary, it enables constant power output outside the constant current output region of the LED driver power supply.

[0052] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0053] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0054] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein can be implemented directly by hardware, a software module executed by a processor, or a combination of both. The software module can be located in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0055] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They do not limit the scope of protection of the present invention. All equivalent changes and modifications made within the scope of the claims of the present invention should fall within the scope of the claims of the present invention.

Claims

1. A power control method, characterized in that, Includes the following steps: After power-on startup, a second current reference is generated based on the first current reference; A second drive current is generated based on the second current reference, and the load is driven to work through the second drive current, so that the load is in a critical working state. The actual operating voltage of the load is collected to obtain a real-time voltage sampling signal; The expected current corresponding to the expected power is obtained by calculating based on the real-time voltage sampling signal. A control quantity is formed based on the expected current and the preset current; The power conversion circuit is adjusted according to the control quantity to achieve closed-loop control of the load output power.

2. The power control method according to claim 1, characterized in that, The step of generating the second current reference based on the first current reference includes: The control unit invokes the first current reference and outputs a second current reference control signal based on the first current reference; The current reference circuit generates the second current reference based on the second current reference control signal.

3. The power control method according to claim 1, characterized in that, The step of generating the second drive current based on the second current reference includes: The current regulation unit performs a comparison and calculation based on the second current reference and the current sampling signal to obtain a first error signal; The power conversion circuit is controlled by the first error signal to perform closed-loop control in order to output the second drive current.

4. The power control method according to claim 1, characterized in that, The process of acquiring the actual operating voltage of the load and obtaining the real-time voltage sampling signal includes: After the load starts working, the voltage sampling circuit samples the actual operating voltage of the load to obtain the real-time voltage sampling signal.

5. The power control method according to claim 1, characterized in that, The step of calculating the expected current based on the real-time voltage sampling signal includes: The control unit acquires the expected power; The control unit calculates the expected current based on the expected power and the real-time voltage sampling signal.

6. The power control method according to any one of claims 1-5, characterized in that, The control quantity formed based on the expected current and the preset current includes: The expected current is compared with the preset current to determine the result; If the expected current is greater than or equal to the preset current, the preset current is selected as the control quantity. If the expected current is less than the preset current, the expected current is selected as the control quantity.

7. The power control method according to claim 6, characterized in that, The step of adjusting the power conversion circuit according to the control quantity to achieve closed-loop control of the load output power includes: The control unit outputs a third current reference control signal according to the control quantity; The current reference circuit generates a third current reference based on the third current reference control signal; The current regulation unit performs a comparison and calculation based on the third current reference and the current sampling signal to obtain a second error signal; The power conversion circuit is controlled by the second error signal to perform closed-loop control in order to output the third drive current; The load is driven to operate by the third driving current; The current sampling circuit performs real-time current sampling during the operation of the load to obtain the real-time current signal of the load, and feeds the real-time current signal back to the current regulation unit; The current regulation unit adjusts the third drive current based on the real-time current signal, so that the third drive current supplies power to the load in a constant current mode.

8. A driving device, characterized in that, include: Control unit, current loop, voltage loop, and power conversion circuit; The control unit is used to generate a second current reference control signal based on a first current reference after the power supply is powered on and started, and to calculate the expected current corresponding to the expected power based on the real-time voltage sampling signal collected by the voltage loop, and to form a control quantity based on the expected current and the preset current. The current loop generates a second current reference based on the second current reference control signal, and generates a second drive current based on the second current reference, so as to drive the load to work through the second drive current, so that the load is in a critical working state. The voltage loop acquires the actual operating voltage of the load to obtain the real-time voltage acquisition signal; The power conversion circuit achieves closed-loop control of the load output power by adjusting the control quantity.

9. An LED driver power supply, characterized in that, Includes the driving device as described in claim 8.

10. A lighting device, characterized in that, Includes the LED driver power supply as described in claim 9.

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