Power factor optimization control method and system, control processing module and electrical equipment

Abstract

The invention relates to the technical field of power factor optimization, and discloses a power factor optimization control method and system, a control processing module and electrical equipment. The method comprises the steps that a target control signal is obtained by adjusting control of a voltage loop, and the target control signal is a corresponding signal when output voltage of the voltage loop is closest to reference voltage; obtaining a target current through a voltage loop according to the target control signal, and inputting the target current to a current loop; and adjusting the control of the current loop according to the target current, so that the output current of the current loop is close to the target current. According to the invention, dynamic adjustment of the phase and the amplitude of the voltage is introduced into current reference calculation, so that the synchronism of the current and the voltage is stronger, and more efficient power factor correction is realized. Therefore, energy waste is reduced, and the overall efficiency of the power system is improved.

Description

Technical Field

[0001] This application relates to the technical field of power factor optimization, and particularly to a power factor optimization control method, system, control processing module, and electrical equipment. Background Art

[0002] The power factor is an important indicator for measuring the relationship between the active power (effective power) and the apparent power in an electrical system. The higher the power factor, the higher the efficiency of electrical energy utilization. When the power factor is at the ideal value (such as 1), all the input electrical energy is effectively converted into useful work. However, in practical applications, many loads, such as non-linear loads, can cause the power factor to be lower than the ideal value, resulting in energy waste in the electrical system. Summary of the Invention

[0003] An object of an embodiment of this application is to provide a power factor optimization control method, system, control processing module, and electrical equipment to solve the technical problem of how to improve the power factor, thereby reducing energy waste and enhancing the overall efficiency of the electrical system.

[0004] To solve the above technical problem, a technical solution adopted in an embodiment of this application is: providing a power factor optimization control method, which is applied to a power factor optimization control system. The power factor optimization control system includes a dual-loop control module, and the dual-loop control module includes a voltage loop and a current loop. The method includes: obtaining a target control signal by adjusting the control of the voltage loop, where the target control signal is the signal corresponding to when the output voltage of the voltage loop is closest to the reference voltage; obtaining a target current through the voltage loop according to the target control signal, and inputting the target current into the current loop; adjusting the control of the current loop according to the target current to make the output current of the current loop close to the target current.

[0005] Optionally, the voltage loop includes a first controller. Obtaining a target control signal by adjusting the control of the voltage loop includes: calculating a voltage error value according to the output voltage and the reference voltage of the voltage loop; inputting the voltage error value into the first controller, and adjusting the control signal output by the first controller through the proportional parameter and the integral parameter in the first controller to make the output voltage close to the reference voltage; obtaining the control signal corresponding to when the output voltage is closest to the reference voltage, and using the control signal corresponding to when it is closest as the target control signal.

[0006] Optionally, input the voltage error value into the first controller, and adjust the control signal output by the first controller through the proportional parameter and integral parameter in the first controller to make the output voltage close to the reference voltage, including: input the voltage error value into the first formula corresponding to the first controller, and the first formula includes a proportional parameter and an integral parameter; calculate the first output voltage according to the first formula; compare the first output voltage with the reference voltage; if the difference between the reference voltage and the first output voltage is greater than the preset voltage threshold, adjust the proportional parameter and the integral parameter, and calculate a new first output voltage according to the adjusted first formula; compare the new first output voltage with the reference voltage, if the difference between the reference voltage and the new first output voltage is greater than the preset voltage threshold, continue to adjust the proportional parameter and the integral parameter, and calculate the output voltage according to the adjusted first formula until the difference between the reference voltage and the obtained output voltage is less than or equal to the preset voltage threshold.

[0007] Optionally, according to the target control signal, obtain the target current through the voltage loop, including: obtain the duty cycle of the target control signal through the voltage loop; calculate the target current according to the duty cycle.

[0008] Optionally, the current loop includes a second controller. According to the target current, adjust the control of the current loop to make the output current of the current loop close to the target current, including: during the adjustment control process of the current loop, calculate the current reference value according to the target current; calculate the current error value according to the current reference value and the actual input current; input the current error value into the second controller, and adjust the control signal output by the second controller through the preset parameters in the second controller to make the output current of the current loop close to the target current.

[0009] Optionally, during the adjustment control process of the current loop, calculate the current reference value according to the target current, including: during the adjustment control process of the current loop, calculate the current reference value according to the following second formula; the second formula is: I1 = Iref × Km × (A × Sin(θ t )) / V rms 2 ; where, I1 is the current reference value, Iref is the target current, Km is the proportionality factor, A is the adjustment factor, Sin(θ t ) is the sine function related to the phase of the AC voltage, θ t is the phase angle related to time t, and V rms is the effective value of the AC voltage.

[0010] Optionally, input the current error value into a second controller, and adjust the control signal output by the second controller through preset parameters in the second controller, so that the output current of the current loop approaches the target current, including: inputting the current error value into a third formula corresponding to the second controller, where the third formula includes preset parameters; calculating a first output current according to the third formula; comparing the first output current with the target current; if the difference between the target current and the first output current is greater than a preset current threshold, adjust the preset parameters, and calculate a new first output current according to the adjusted third formula; compare the new first output current with the target current, if the difference between the target current and the new first output current is greater than the preset current threshold, continue to adjust the preset parameters, and calculate the output current according to the adjusted third formula until the difference between the target current and the obtained output current is less than or equal to the preset current threshold.

[0011] To solve the above technical problems, a technical solution adopted in an embodiment of the present application is: to provide a control processing module, including: a memory and a processor, the memory is connected to the processor, and the processor is used to execute one or more computer programs stored in the memory. When the processor executes the one or more computer programs, the control processing module implements a power factor optimization control method applied to the control processing module.

[0012] To solve the above technical problems, a technical solution adopted in an embodiment of the present application is: to provide a power factor optimization control system, including: a dual-loop control module, a voltage and current sensor, a PWM signal modulation module, and the above control processing module. The dual-loop control module includes a voltage loop and a current loop; the voltage and current sensor is used to sample voltage and current data, and provide the sampled voltage and current data to the control processing module; the control processing module performs dual-loop control on the dual-loop control module based on the voltage and current data, specifically including: obtaining a target control signal by adjusting the control of the voltage loop, where the target control signal is the signal corresponding to when the output voltage of the voltage loop is closest to the reference voltage; obtaining a target current through the voltage loop according to the target control signal, and inputting the target current into the current loop; adjusting the control of the current loop according to the target current, so that the output current of the current loop approaches the target current; the control processing module is further used to provide the output current closest to the target current to the PWM signal modulation module; the PWM signal modulation module is used to generate a PWM signal according to the output current closest to the target current, and the PWM signal is used to control the waveforms and amplitudes of the output voltage and current to optimize the power factor.

[0013] To solve the above technical problems, a technical solution adopted in an embodiment of the present application is: to provide an electrical device, including the power factor optimization control system as described above.

[0014] The power factor optimization control method, system, control processing module, and electrical equipment provided by the embodiments of the present application adjust the voltage loop to keep the output voltage near the set value, avoiding the unstable influence of voltage fluctuations on the power factor. Generate a target current according to the output signal of the voltage loop, which ensures that the target current matches the voltage waveform. This is the key to improving the power factor because the smaller the phase difference, the higher the power factor. By adjusting the current loop, the actual output current approaches the target current, which ensures that the output current waveform is close to the target current waveform, so that the amplitude and phase of the current are synchronized with the voltage, maximizing the active power, reducing the reactive power, and improving the power factor. Thereby, energy waste is reduced and the overall efficiency of the power system is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments of the present application. Obviously, the following drawings are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0016] Figure 1 is a schematic structural diagram of a power factor optimization control system provided by the embodiments of the present application;

[0017] Figure 2 is a flowchart of a power factor optimization control method provided by the embodiments of the present application;

[0018] Figure 3 is a flowchart of a method for obtaining a target control signal by adjusting the control of the voltage loop provided by the embodiments of the present application;

[0019] Figure 4 is a flowchart of a method for adjusting the control of the current loop according to the target current provided by the embodiments of the present application;

[0020] Figure 5 is a flowchart of the algorithm corresponding to the dual-loop control algorithm provided by the embodiments of the present application;

[0021] Figure 6 is a schematic structural diagram of a control processing module provided by the embodiments of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0022] In order to make the objectives, technical solutions and advantages of this application more clear and understandable, the following further elaborates on this application in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not used to limit this application. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of this application.

[0023] It should be noted that if there is no conflict, the various features in the embodiments of this application can be combined with each other, and all are within the scope of protection of this application. Additionally, although functional module division is carried out in the device schematic diagram and the logical sequence is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order from the module division in the device or the sequence in the flowchart. Furthermore, the terms "first", "second", "third", etc. used in this application do not limit the data and execution order, but are only used to distinguish the same items or similar items with basically the same functions and effects.

[0024] Power factor refers to the ratio of the active power to the apparent power in an AC circuit, representing the efficiency of electrical energy conversion. Active power is the part of the power in an AC circuit that can be converted into actual useful work. It represents the power that can actually be consumed and converted into useful work, and can be used to drive devices such as motors, lighting, and heating. Apparent power is the total power of voltage and current, that is, the total electrical power without considering the power factor. Apparent power is the total power provided by the power supply, including the part that can do work (active power) and the part that cannot do work (reactive power). Reactive power is the power in an AC circuit that does not do actual work but affects the phase difference between current and voltage. Power factor is the ratio of active power to apparent power, representing the efficiency of the power system and reflecting whether the power system can effectively convert electrical energy into useful work. Its value range can be from 0 to 1, and the closer it is to 1, the higher the energy efficiency of the system.

[0025] PFC (Power Factor Correction) is a technology used to improve the efficiency of the power system. The PFC technology adjusts the current waveform to minimize its phase difference from the voltage waveform, thereby improving the power factor, reducing reactive power, and enhancing the efficiency of the system. This is crucial for reducing energy waste and improving the stability and economy of the power system.

[0026] Although traditional PFC technology has been able to effectively improve the power factor (PF), many existing systems still cannot maintain the optimal power factor under large-scale load variations. With the continuous increase in power demand, especially for high-power devices (such as industrial equipment, servers, LED lighting, etc.), traditional PFC methods may fail to minimize reactive power, resulting in a decrease in system efficiency and even affecting the stability of the power grid.

[0027] Therefore, the embodiments of this application provide a power factor optimization control method. By introducing the dynamic adjustment of the phase and amplitude of the voltage into the current reference calculation, the synchronization between the current and the voltage is enhanced, thus achieving more efficient power factor correction. This method can optimize the power factor under a wider range of load conditions, improve system performance, and at the same time reduce the negative impacts on the power grid and equipment, which is crucial for the efficient utilization of energy, the safety of equipment operation, and the sustainability of the power system. The power factor optimization control scheme will be introduced through specific embodiments below.

[0028] Please refer to Figure 1 , Figure 1 which is a schematic structural diagram of a power factor optimization control system provided by the embodiments of this application. The power factor optimization control system 10 includes a dual-loop control module 11, a voltage-current sensor 12, a PWM signal modulation module 13, and a control processing module 14. The dual-loop control module 11, the voltage-current sensor 12, and the PWM signal modulation module 13 are respectively connected to the control processing module 14, and these modules work together to optimize the power factor and improve system efficiency.

[0029] The dual-loop control module 11 is used to precisely control the voltage and current and ensure power factor optimization. In this dual-loop control module 11, there are two loops: a voltage loop and a current loop. These two loops work together to adjust the current waveform to make it as synchronous with the voltage waveform as possible, thereby improving the power factor. Among them, the voltage loop is used to calculate the voltage error value based on the difference between the input voltage and the reference voltage, and input it into the controller of the voltage loop. By adjusting the proportional parameter and the integral parameter in this controller, the control signal is adjusted to make the output voltage as close to the reference voltage as possible. The controller of the voltage loop adjusts the output of the voltage loop, thereby achieving voltage stabilization control. The current loop is used to calculate the target current value based on the control output of the voltage loop and transmit it to the current loop. The current loop uses its corresponding controller to adjust according to the error between the target current and the actual current, so that the output current is as close to the target current as possible. The current waveform is synchronized with the voltage waveform, thus achieving power factor optimization.

[0030] Among them, the main objective of the voltage loop is to control the output voltage to be as consistent as possible with the reference voltage. The control structure of this voltage loop may include an error calculation unit, a first controller, and an output regulation unit. The error calculation unit is used to calculate the error between the sampled output voltage and the reference voltage, which can specifically be a simple subtractor for calculating the voltage error. The first controller can specifically be a PI controller (Proportional-Integral controller), which adjusts the control signal based on the voltage error through proportional and integral parameters. The PI controller is the core component, and it generates a control signal to adjust the operating state of the power switch element. The output regulation unit is used to output the control signal, which can be provided to the PWM signal modulation module 13 and can be converted into a PWM signal. The control structure of this current loop is similar to that of the voltage loop and can include an error calculation unit, a second controller, and an output regulation unit. The error calculation unit is used to calculate the error between the sampled output current and the reference current, which can also be a simple subtractor for calculating the current error. The second controller can also be a PI controller (Proportional-Integral controller). Similar to the voltage loop, the current loop also uses a PI controller to process the current error and generate a control signal. The output regulation unit is used to output the control signal, which can be provided to the PWM signal modulation module 13 and can be converted into a PWM signal.

[0031] In this embodiment, the voltage loop preferentially ensures that the voltage output by the system is stable and maintained at a preset value. The current loop ensures that the output current is synchronized with the reference current and optimizes the power factor. In implementation, the control signal (voltage signal) output by the voltage loop is input as the reference current of the current loop. The current loop then adjusts the output current to optimize the power factor based on this reference current and makes the current waveform as synchronous as possible with the voltage waveform.

[0032] The voltage-current sensor 12 is used to sample voltage and current data in real time and provide this data to the control processing module 14 for further processing. The voltage-current sensor 12 includes a voltage sensor and a current sensor. The voltage sensor can be used to collect the waveform of the input voltage in real time and convert it into a digital signal for transmission to the control processing module 14. The current sensor can be used to collect the current waveform (including the output current and the input current) in real time and convert it into a digital signal, which is also transmitted to the control processing module 14. The sampled data of voltage and current provide real-time feedback to the control processing module 14 to help the control processing module 14 achieve closed-loop control. Among them, the voltage sensor can use a voltage divider or a voltage sensor chip to collect the voltage signal. The current sensor can adopt a Hall effect sensor or a current transformer, etc.

[0033] The PWM signal modulation module 13 is used to generate corresponding PWM (pulse width modulation) signals according to the control signals provided by the control processing module 14, so as to adjust the waveforms and amplitudes of the output voltage and current of the power electronic switch. Among them, the control processing module 14 calculates the output current closest to the target current according to the output signal of the current loop. According to this output current, the PWM signal modulation module 13 converts it into a corresponding PWM signal. This PWM signal controls the switching frequency and duty cycle of power switch elements (such as MOSFETs, IGBTs, etc.), thereby adjusting the waveforms and amplitudes of the output voltage and current.

[0034] The control processing module 14 is the core of the entire power factor optimization control system 10, and is used to receive the data provided by the voltage and current sensors 12, execute the dual-loop control algorithm (that is, the power factor optimization control method of the embodiment of the present application), and adjust the voltage and current loops of the dual-loop control module 11 according to real-time feedback to optimize the power factor. Among them, the control processing module 14 receives real-time voltage and current data from the voltage and current sensors 12. The control processing module 14 executes the dual-loop control algorithm based on the collected data and calculates the adjustment values required for the voltage loop and the current loop. The control processing module 14 sends this adjustment signal to the dual-loop control module 11 to instruct the voltage loop and the current loop to make adjustments. The dual-loop control module 11 adjusts the switching state of the power switch element according to the received signal, and then adjusts the output voltage and current to achieve power factor optimization.

[0035] In this embodiment, the power factor optimization control system 10 effectively improves the power factor of the system and reduces the waste of reactive power by accurately adjusting the waveforms and amplitudes of the voltage and current through the dual-loop control algorithm. By accurately controlling the phase synchronization of the output current and the input voltage, not only the energy conversion efficiency of the power system is optimized, but also the burden on the power system is reduced, and the stability and economy of the overall power system are improved.

[0036] This power factor optimization control system can be applied to various electrical equipment, specifically including: switching power supplies (such as power adapters, LED drive power supplies, UPS uninterruptible power supplies, etc.), motor drive systems (such as motor drive modules in household appliances such as air conditioners, refrigerators, washing machines, fans, etc.), household appliances (such as televisions, audio systems, rice cookers, electric water heaters, etc.), electric vehicle charging equipment (such as electric vehicle charging piles, charging stations, etc.).

[0037] Please refer to Figure 2 , Figure 2It is a flowchart of a power factor optimization control method provided by an embodiment of the present application. This method can be applied to the power factor optimization control system in the above embodiment. The power factor optimization control system includes a dual-loop control module, and the dual-loop control module includes a voltage loop and a current loop. The method includes the following steps:

[0038] S11. Obtain a target control signal by adjusting the control of the voltage loop. The target control signal is the signal corresponding to when the output voltage of the voltage loop is closest to the reference voltage.

[0039] Among them, the target control signal refers to the control signal obtained through the voltage loop control process, and this signal is the output result during the voltage loop adjustment process. Specifically, it represents the control signal when the output voltage of the voltage loop is closest to the reference voltage.

[0040] Among them, the voltage loop includes a first controller. Please refer to Figure 3 , obtaining the target control signal by adjusting the control of the voltage loop includes:

[0041] S111. Calculate the voltage error value according to the output voltage and the reference voltage of the voltage loop.

[0042] Among them, the output voltage of the voltage loop and the reference voltage are subtracted from each other, and the absolute value of the result of the subtraction operation is taken as the voltage error value. The output voltage is the DC output voltage. In a PFC circuit (power factor correction circuit), the voltage loop can control a boost converter (for example, BOOST topology) to ensure the stability of the output voltage, usually a DC voltage. The output voltage can also be the rectified alternating current, and then through the adjustment of the voltage loop, it is converted into a stable DC voltage. The reference voltage is a set ideal voltage value, and the system adjusts the control signal in the voltage loop to make the output voltage as close as possible to this reference voltage.

[0043] S112. Input the voltage error value into the first controller, and adjust the control signal output by the first controller through the proportional parameter and the integral parameter in the first controller to make the output voltage close to the reference voltage.

[0044] The task of the voltage loop is to make the output voltage as close as possible to the reference voltage. To achieve this goal, the system will adjust according to the error between the output voltage and the reference voltage. The smaller the error, the more stable the system and the closer the output voltage is to the reference voltage.

[0045] Specifically, input the voltage error value into the first formula corresponding to the first controller. The first formula includes a proportional parameter and an integral parameter. Calculate the first output voltage according to the first formula. Compare the first output voltage with the reference voltage. If the difference between the reference voltage and the first output voltage is greater than the preset voltage threshold, adjust the proportional parameter and the integral parameter, and calculate the new first output voltage according to the adjusted first formula. Compare the new first output voltage with the reference voltage. If the difference between the reference voltage and the new first output voltage is greater than the preset voltage threshold, continue to adjust the proportional parameter and the integral parameter, and calculate the output voltage according to the adjusted first formula until the difference between the reference voltage and the obtained output voltage is less than or equal to the preset voltage threshold.

[0046] Among them, the first controller can specifically be a PI controller. The first formula is specifically: k p is the proportional parameter, and k i is the integral parameter. The value ranges of the proportional parameter and the integral parameter can both be (0, 1). e(t) is the voltage error value. u (t) is the result of reacting to the voltage error by adjusting the proportional and integral terms, that is, the above-mentioned first output voltage.

[0047] Among them, when adjusting the proportional parameter and the integral parameter, it can be adjusted based on experience. For example, first adjust the proportional parameter. The proportional parameter controls the immediate response of the system to the voltage error. A higher proportional parameter will make the system have a stronger response to the voltage error, thus correcting the voltage deviation faster, but it may lead to overreaction or oscillation. A lower proportional parameter has a slower response but is more stable. Then adjust the integral parameter. The integral term can eliminate the steady-state error in the system. It accumulates the change of the voltage error over time, so that the system finally reaches zero error (eliminating continuous small errors). If the integral parameter is too large, it may introduce overcompensation or instability into the system. Consider these factors to adjust the proportional parameter and the integral parameter. When adjusting the proportional parameter and the integral parameter, an automatic adjustment method can also be adopted to dynamically adjust the proportional parameter and the integral parameter in real-time according to the voltage error. For example, when the error value is large, increase the proportional parameter to respond quickly. When the system has a steady-state error (that is, the error persists for a period of time), eliminate the error by increasing the integral parameter. When the error value is close to zero, reduce the proportional parameter to avoid overcorrection and oscillation.

[0048] Among them, the preset voltage threshold is a parameter used to determine when to stop adjustment, and it defines the maximum acceptable difference between the target voltage and the actual voltage. When setting this preset voltage threshold, if the system has high requirements for voltage control accuracy (for example, the output voltage is required to be very close to the reference voltage), then this voltage threshold should be set smaller. For example, the output voltage error is required to be less than 1% or lower, which can ensure that the system works stably within a very small error range. For some applications that do not require extremely high precision, the threshold can be appropriately increased to reduce the adjustment frequency of the control system, thereby improving the response speed and efficiency.

[0049] S113. Obtain the control signal corresponding to when the output voltage is closest to the reference voltage, and use the control signal corresponding to when it is closest as the target control signal.

[0050] According to the above first formula, it is known that u (t) is the response result of the first controller to the voltage error. It is the result obtained by the first controller through proportional and integral regulation of the voltage error, and it is the control quantity calculated by the first controller. This control quantity can be converted into a control signal, and thus the target control signal is obtained.

[0051] S12. According to the target control signal, obtain the target current through the voltage loop, and input the target current into the current loop.

[0052] Among them, the duty cycle of the target control signal can be obtained through the voltage loop. According to this duty cycle, the target current is calculated, and then the target current is input into the current loop. The control output duty cycle of the voltage loop determines the working state of the power switch element. Through this duty cycle, the target current can be deduced because the current is determined by the characteristics of the voltage and the load. The relationship between the target current and the duty cycle depends on the power supply topology, load conditions, and the control strategy adopted. For example, in a BOOST PFC (Power Factor Correction) circuit, the relationship between the current, input voltage, duty cycle, and output voltage is usually determined by the topology. In some systems, other factors may also need to be considered, such as inductance, voltage ripple, etc.

[0053] The calculated target current will be input into the current loop as the reference current of the current loop. The task of the current loop is to adjust the output current to track this target current, thereby optimizing the current waveform, reducing power loss, and improving the power factor.

[0054] S13. According to the target current, adjust the control of the current loop to make the output current of the current loop close to the target current.

[0055] Among them, the current loop includes a second controller, please refer to Figure 4, according to the target current, adjust the control of the current loop so that the output current of the current loop approaches the target current, including:

[0056] S131. During the adjustment control process of the current loop, calculate the current reference value according to the target current.

[0057] Among them, during the adjustment control process of the current loop, calculate the current reference value according to the following second formula. The second formula is: I1 = Iref × Km × (A × Sin(θ t )) / V rms 2 ; where, I1 is the current reference value, Iref is the target current, Km is the proportionality factor, A is the adjustment factor, Sin(θ t ) is the sine function related to the AC voltage phase, θ t is the phase angle related to time t, V rms is the effective value of the AC voltage. A and Sin(θ t ) can be constants.

[0058] The second formula is based on the phase relationship between voltage and current, and optimizes the current waveform through specific parameter adjustments, so as to improve the power factor in subsequent steps. Among them, by adjusting A and Km, the current reference value can be accurately controlled according to the needs of the system. This adjustment mechanism can compensate the current according to voltage fluctuations, thereby improving the power factor. A reflects the amplitude adjustment of the current waveform, while Km further adjusts the overall gain of the current. V rms 2 is used to combine the current reference value with the effective value of the voltage, which ensures that the physical relationship between the current reference value and the voltage remains consistent. Since the current waveform needs to be synchronized with the voltage waveform, Sin(θ t ) is used to obtain the instantaneous value of the current, so as to adjust the current to make it consistent with the voltage phase.

[0059] S132. Calculate the current error value according to the current reference value and the actual input current.

[0060] The actual input current can be expressed as: Iref × (A × Sin(θ t )) / V rms 2 . Subtract the obtained current reference value I1 from the actual input current, and the difference is the current error value, which is used as the input of the second controller. Among them, the difference can take the absolute value.

[0061] S133. Input the current error value into the second controller, and adjust the control signal output by the second controller through the preset parameters in the second controller, so that the output current of the current loop approaches the target current.

[0062] Among them, the current error value is input into the third formula corresponding to the second controller, and the third formula includes preset parameters; the first output current is calculated according to the third formula; the first output current is compared with the target current; if the difference between the target current and the first output current is greater than the preset current threshold, the preset parameters are adjusted, and the new first output current is calculated according to the adjusted third formula; the new first output current is compared with the target current. If the difference between the target current and the new first output current is greater than the preset current threshold, the preset parameters are continuously adjusted, and the output current is calculated according to the adjusted third formula until the difference between the target current and the obtained output current is less than or equal to the preset current threshold.

[0063] Among them, the third formula is: u(k) = b0e(k) + b1e(k - 1) + b2e(k - 2) - a1u(k - 1) - a2u(k - 2). b0, b1, b2, a1, and a2 are the preset parameters, and these preset parameters are used to adjust the gain of the current. The value ranges of these five parameters can all be (-10 to 10). u(k) is the control signal at the current moment. e(k) is the current error value of the current moment. e(k - 1) and e(k - 2) are the current error values of the previous two moments. u(k - 1) and u(k - 2) are the control signals of the previous two moments.

[0064] The second controller uses the above third formula to calculate the control signal. The third formula is discrete. The control signal u(k) is the adjustment output of the system, and it can affect the behavior of the controller (such as the on-off state, frequency, duty cycle, etc. of the power switch), thereby adjusting the output of the current. The error terms include e(k), e(k - 1), and e(k - 2), which reflect the current error of the system at the current and the previous two moments. The controller will adjust the output according to the past and current current errors to reduce the current error. The control signal terms include u(k - 1) and u(k - 2), which reflect the influence of the previous two control outputs. The controller improves the current control signal by referring to the past control behavior.

[0065] If the system error is large (that is, there is a large gap between the target current and the actual current), the control signal u(k) will be large, so as to adjust the output current faster and make it closer to the target current. If the error is small, the control signal u(k) will be small to avoid instability caused by over-regulation.

[0066] Reduce the error by adjusting the control signal in real time to ensure that the output current is close to the target current. As the system continuously executes this formula, the control signal gradually reduces the current error until the set current threshold is reached or the error is less than a certain preset range. This means that the system can precisely control the waveform and amplitude of the current, ensuring that the current is consistent with the target current, thereby improving the stability and response speed of the system. Moreover, the control system precisely controls the current to keep it better synchronized with the voltage waveform. By reducing the current error, the system can more effectively transfer electrical energy to the load, reduce reactive power, and thus improve the power factor and reduce the consumption of reactive power. This not only improves the efficiency of the power system but also reduces the burden on the power grid by the equipment.

[0067] Please refer to Figure 5 , the power factor optimization control method of the embodiment of the present application may specifically be as Figure 5The double-loop control algorithm shown. In this embodiment, a power factor optimization control method is implemented under the BOOST PFC framework. In the BOOST PFC framework, the system uses a BOOST topology boost converter. By adjusting the switching frequency and duty cycle of the switching device, the control system can change the waveforms of the output voltage and current, thereby achieving power factor optimization. The double-loop control algorithm includes a voltage loop and a current loop. In the application of BOOST PFC, these two loops are respectively responsible for voltage control and current control. The voltage loop is used to maintain the stability of the output voltage. Its core purpose is to ensure that the difference between the output voltage and the reference voltage is minimized, and precise voltage control is achieved by adjusting the control signal. The current loop is used to control the input current so that the phase relationship between the input current and the input voltage is close, thereby achieving the effect of power factor optimization. Through current loop control, the system can adjust the input current to match the input voltage waveform and improve the power factor. Specifically, the voltage error is input to a PI controller, and the proportional parameter (Kp) and integral parameter (Ki) are adjusted to generate a control signal. This control signal determines the switching frequency and duty cycle of the BOOST converter, thereby adjusting the output voltage. In this loop, by precisely adjusting the voltage error, the voltage loop ensures that the output voltage is close to the reference voltage and provides a stable target current for the current loop. The input of the current loop is the target current calculated by the voltage loop. The current error (the difference between the target current and the actual input current) is input to a second controller (such as a PI controller or a 2P2Z controller). The controller adjusts the output control signal according to the current error, and then adjusts the switching frequency and duty cycle of the BOOST converter. According to the control signal of the current loop, the PWM signal modulation module generates a control signal for controlling the switching element (such as a MOSFET) in the BOOST converter. The duty cycle of the PWM signal determines the waveform and amplitude of the output current, thereby affecting the optimization of the power factor. By precisely controlling the duty cycle, the system can effectively adjust the phase relationship between the input current and the voltage and optimize the power factor.

[0068] In this embodiment, the double-loop control algorithm is applied under the BOOST PFC framework. By precisely adjusting the voltage and current and optimizing the phase relationship between the input current and the voltage, the power factor can be effectively improved, the reactive power can be reduced, the system efficiency can be increased, and the current harmonics can be reduced, thereby achieving the optimization of the power factor. This control method not only improves the utilization rate of electric energy but also provides guarantee for the stable operation of the power system.

[0069] Please refer to Figure 6 , Figure 6It is a schematic structural diagram of a control processing module provided by an embodiment of the present application. The control processing module 14 includes one or more processors 141 and a memory 142. The memory 142 is connected to one or more processors 141, for example, connected to the processor 141 through a bus.

[0070] The processor 141 is configured to support the control processing module to execute the corresponding functions in the method of the above method embodiment. The processor 141 may be a central processing unit (CPU), a network processor (NP), a hardware chip, or any combination thereof. The above hardware chip may be an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a combination thereof. The above PLD may be a complex programmable logic device (CPLD), a field-programmable gate array (FPGA), a generic array logic (GAL), or any combination thereof.

[0071] The memory 142 is used to store program codes and the like. The memory 142 may include a volatile memory (VM), such as a random access memory (RAM); the memory 142 may also include a non-volatile memory (NVM), such as a read-only memory (ROM), a flash memory, a hard disk drive (HDD), or a solid-state drive (SSD); the memory 142 may further include a combination of the above types of memories.

[0072] The memory 142 can be used to store non-volatile software programs, non-volatile computer executable programs, and modules, such as the program instructions / modules corresponding to the power factor optimization control method in the embodiment of the present application. The processor 141 executes various functional applications and data processing of the power factor optimization control method by running the non-volatile software programs, instructions, and modules stored in the memory 142, that is, implements the power factor optimization control method provided by the above method embodiment.

[0073] The memory 142 may include a program storage area and a data storage area. The program storage area may store an operating system and application programs required for at least one function. The data storage area may store data created according to the usage, etc.

[0074] The one or more modules are stored in the memory 142 and, when executed by the one or more processors 141, perform the power factor optimization control method in any of the above method embodiments. For example, the method steps described in the above method embodiments are executed.

[0075] Those of ordinary skill in the art can understand that all or part of the processes of implementing the methods in the above embodiments can be completed by instructing relevant hardware through a computer program. The program can be stored in a computer-readable storage medium. When the program is executed, it may include the processes of the embodiments of the above methods. Among them, the storage medium may be a magnetic disk, an optical disk, a read-only memory (ROM), or a random access memory (RAM), etc.

[0076] The above-disclosed are only the preferred embodiments of the present application. Of course, the scope of the rights of the present application cannot be limited thereby. Therefore, equivalent changes made according to the claims of the present application still fall within the scope covered by the present application.

Claims

1. A power factor optimization control method, characterized in that: The method is applied to a power factor optimization control system, the power factor optimization control system includes a dual-loop control module, the dual-loop control module includes a voltage loop and a current loop, and the method includes: By adjusting the control of the voltage loop, a target control signal is obtained, wherein the target control signal is a signal corresponding to when the output voltage of the voltage loop is closest to the reference voltage; According to the target control signal, a target current is obtained through the voltage loop, and the target current is input into the current loop; According to the target current, the control of the current loop is adjusted so that the output current of the current loop is close to the target current.

2. The method according to claim 1, characterized in that The voltage loop includes a first controller, and the target control signal is obtained by adjusting the control of the voltage loop, including: Calculating a voltage error value according to an output voltage of the voltage loop and a reference voltage; Inputting the voltage error value into the first controller, and adjusting the control signal output by the first controller by using the proportional parameter and the integral parameter in the first controller, so that the output voltage is close to the reference voltage; A control signal corresponding to when the output voltage is closest to the reference voltage is obtained, and the control signal corresponding to when the output voltage is closest to the reference voltage is used as the target control signal.

3. The method according to claim 2, characterized in that The step of inputting the voltage error value into the first controller and adjusting the control signal output by the first controller by using a proportional parameter and an integral parameter in the first controller so that the output voltage is close to the reference voltage comprises: Inputting the voltage error value into a first formula corresponding to the first controller, wherein the first formula includes the proportional parameter and the integral parameter; Calculate a first output voltage according to the first formula; comparing the first output voltage with the reference voltage; If the difference between the reference voltage and the first output voltage is greater than a preset voltage threshold, adjusting the proportional parameter and the integral parameter, and calculating a new first output voltage according to the adjusted first formula; The new first output voltage is compared with the reference voltage. If the difference between the reference voltage and the new first output voltage is greater than the preset voltage threshold, the proportional parameter and the integral parameter are continuously adjusted, and the output voltage is calculated according to the adjusted first formula until the difference between the reference voltage and the obtained output voltage is less than or equal to the preset voltage threshold.

4. The method according to any one of claims 1 to 3, characterized in that: The step of obtaining a target current through the voltage loop according to the target control signal includes: Obtaining a duty cycle of the target control signal through the voltage loop; A target current is calculated according to the duty cycle.

5. The method according to claim 1, characterized in that The current loop includes a second controller, and the control of the current loop is adjusted according to the target current so that the output current of the current loop is close to the target current, including: In the regulation and control process of the current loop, a current reference value is calculated according to the target current; Calculating a current error value according to the current reference value and the actual input current; The current error value is input into the second controller, and the control signal output by the second controller is adjusted by preset parameters in the second controller so that the output current of the current loop is close to the target current.

6. The method according to claim 5, characterized in that In the regulation and control process of the current loop, calculating the current reference value according to the target current includes: In the regulation and control process of the current loop, a current reference value is calculated according to the following second formula; The second formula is: I1 = Iref × Km × (A × Sin (θ t )) / V rms 2 ; Where I1 is the current reference value, Iref is the target current, Km is the proportional factor, A is the adjustment factor, Sin(θ t ) is a sinusoidal function related to the phase of the AC voltage, θ t is the phase angle associated with time t, V rms is the effective value of AC voltage.

7. The method according to claim 5, characterized in that The step of inputting the current error value into the second controller and adjusting the control signal output by the second controller by using preset parameters in the second controller so that the output current of the current loop is close to the target current includes: Inputting the current error value into a third formula corresponding to the second controller, wherein the third formula includes preset parameters; Calculate the first output current according to the third formula; comparing the first output current with the target current; If the difference between the target current and the first output current is greater than a preset current threshold, the preset parameter is adjusted, and a new first output current is calculated according to the adjusted third formula; The new first output current is compared with the target current. If the difference between the target current and the new first output current is greater than the preset current threshold, the preset parameters are continued to be adjusted, and the output current is calculated according to the adjusted third formula until the difference between the target current and the obtained output current is less than or equal to the preset current threshold.

8. A control processing module, characterized in that: include: A memory and a processor, wherein the memory is connected to the processor, and the processor is used to execute one or more computer programs stored in the memory, and when the processor executes the one or more computer programs, the control processing module implements the method described in any one of claims 1-7.

9. A power factor optimization control system, characterized in that: include: A dual-loop control module, a voltage and current sensor, a PWM signal modulation module, and a control processing module as claimed in claim 8, wherein the dual-loop control module includes a voltage loop and a current loop; The voltage and current sensor is used to sample voltage and current data, and provide the sampled voltage and current data to the control processing module; The control processing module performs dual-loop control on the dual-loop control module based on the voltage and current data, specifically including: By adjusting the control of the voltage loop, a target control signal is obtained, wherein the target control signal is a signal corresponding to when the output voltage of the voltage loop is closest to the reference voltage; According to the target control signal, a target current is obtained through the voltage loop, and the target current is input into the current loop; According to the target current, adjusting the control of the current loop so that the output current of the current loop is close to the target current; The control processing module is further used to provide the output current closest to the target current to the PWM signal modulation module; The PWM signal modulation module is used to generate a PWM signal according to an output current that is closest to the target current, and the PWM signal is used to control the waveform and amplitude of the output voltage and current to optimize the power factor.

10. An electrical device, characterized in that: It includes the power factor optimization control system as described in claim 9.

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