Mppt control device, method and apparatus for solar panel

Abstract

This paper provides an MPPT control device, method, and apparatus for solar panels. The device includes: a sampling module for acquiring the previous cycle output voltage and output current of the solar panel, and the previous cycle output voltage of the conversion module; a calculation module for calculating the current cycle input voltage reference value of the conversion module according to a preset algorithm; an adjustment module for obtaining the current cycle input voltage parameters of the conversion module through preset adjustment rules; and a conversion module for performing voltage conversion on the previous cycle output voltage of the solar panel according to the current cycle input voltage parameters to achieve maximum power point tracking of the solar panel. This paper performs adjustment control at both the input and output ends of the conversion module, so that the input and output voltages of the conversion module are stably controlled, thereby improving the efficiency of maximum power point tracking.

Description

Technical Field

[0001] This invention relates to the field of new energy power generation, specifically to an MPPT control device, method, and equipment for solar panels. Background Technology

[0002] With the increasing scarcity of conventional energy sources such as oil, solar energy, as a renewable energy source with abundant reserves, is receiving growing attention. Photovoltaic power generation is one of the main ways to utilize solar energy. However, current photovoltaic cells suffer from drawbacks such as low conversion efficiency and susceptibility to weather conditions, severely limiting the large-scale application of solar energy. Therefore, how to effectively increase the output power of solar cells to fully utilize solar energy is an important direction in photovoltaic research.

[0003] Solar-powered drones have advantages such as long flight time, low noise, energy saving, and environmental friendliness, and have broad application prospects. As a core component of the solar-powered drone's energy system, the maximum power point tracking (MPPT) control device's main task is to extract the maximum usable power from the solar cell array during the drone's flight.

[0004] MPPT control devices are typically equipped with DC-DC (Direct Current-Direct Current) converters. During MPPT tracking, the input and output voltages of the DC-DC converter are difficult to control directly, leading to unstable output voltage. This makes it difficult to provide a continuous and stable voltage to the load, affecting its normal operation. Therefore, improving the stability of the output voltage of the DC-DC converter has become an urgent technical problem to be solved. Summary of the Invention

[0005] In view of the above-mentioned problems in the prior art, the purpose of this paper is to provide an MPPT control device, method and apparatus for solar panels, which can improve the stability of the output voltage of DC-DC converters in the prior art.

[0006] To solve the above-mentioned technical problems, the specific technical solution presented in this paper is as follows:

[0007] In a first aspect, this article provides an MPPT control device for solar panels, the device comprising a sampling module, a calculation module, an adjustment module, and a conversion module;

[0008] The sampling module is used to collect the previous cycle output voltage and previous cycle output current of the solar panel, as well as the previous cycle output voltage of the conversion module.

[0009] The calculation module is used to obtain the previous cycle output voltage and previous cycle output current of the solar panel, and calculate the current cycle input voltage reference value of the conversion module according to a preset algorithm.

[0010] The adjustment module is used to obtain the current cycle input voltage parameter of the conversion module based on the previous cycle output voltage of the solar panel, the previous cycle output voltage of the conversion module, and the current cycle input voltage reference value of the conversion module, combined with a preset adjustment rule.

[0011] The conversion module is used to perform voltage conversion on the output voltage of the solar panel in the current cycle according to the input voltage parameters of the current cycle, so as to realize the maximum power point tracking of the solar panel.

[0012] Secondly, based on the aforementioned device, this paper also provides an MPPT control method for solar panels, the method comprising the following steps:

[0013] Obtain the previous cycle output voltage and output current of the solar panel, as well as the previous cycle output voltage of the conversion module;

[0014] Based on the previous cycle output voltage and previous cycle output current of the solar panel, the reference value of the current cycle input voltage of the conversion module is calculated by a preset algorithm.

[0015] Based on the previous cycle output voltage of the solar panel, the previous cycle output voltage of the conversion module, and the current cycle input voltage reference value of the conversion module, the current cycle input voltage parameter of the conversion module is obtained through a preset adjustment rule.

[0016] Based on the current cycle input voltage parameters, the output voltage of the solar panel in the previous cycle is transformed, and it is determined whether the current cycle output power of the solar panel has reached the maximum power point.

[0017] If the current cycle output power of the solar panel does not reach the maximum power point, the steps of obtaining the output power of the solar panel are repeated to achieve maximum power point tracking of the solar panel.

[0018] Thirdly, this article also provides an apparatus equipped with a solar panel, and the apparatus further includes the MPPT control device for the solar panel described above.

[0019] By adopting the above technical solution, the MPPT control device, method and equipment for solar panels described in this article achieves maximum power point tracking by controlling the output voltage and output current of the solar panel, ensuring that the solar panel outputs the maximum available power. At the same time, regulation and control are performed at both the input and output ends of the converter, so that the input and output voltages of the converter are stably controlled, thereby improving the efficiency of maximum power point tracking.

[0020] To make the above and other objects, features and advantages of this document more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments or prior art described herein, the accompanying drawings used in the description of the embodiments or prior art will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this article. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 A schematic diagram of the structure of the MPPT control device for solar panels provided in the embodiments of this article is shown;

[0023] Figure 2 A schematic diagram of the adjustment module in the embodiments of this article is shown;

[0024] Figure 3 The control signal framework diagram of the transformation module in this embodiment is shown;

[0025] Figure 4 A schematic diagram of the control circuit of the solar panel in the embodiment of this article is shown;

[0026] Figure 5 A schematic diagram of the topology of the transformation module in the embodiments of this paper is shown;

[0027] Figure 6 The equivalent circuit diagram of the buck mode of the converter module in the embodiments of this paper is shown;

[0028] Figure 7 The equivalent circuit diagram of the converter module in boost mode in the embodiments of this paper is shown;

[0029] Figure 8 A schematic diagram illustrating the steps of the MPPT control method for solar panels provided in the embodiments of this article is shown.

[0030] Figure 9 A schematic diagram of the structure of a device provided in the embodiments of this article is shown.

[0031] Explanation of symbols in the attached drawings:

[0032] 100. Solar panels;

[0033] 200. Sampling module;

[0034] 300. Calculation module;

[0035] 400. Adjustment module;

[0036] 500. Transformation module;

[0037] 410. First adjustment unit;

[0038] 420. Second adjustment unit;

[0039] 510. Step-down switch branch;

[0040] 511. Input filter capacitor;

[0041] 512. First power switch;

[0042] 513. Second power switch;

[0043] 520. Power inductor;

[0044] 530. Step-up switch branch;

[0045] 531. Output filter capacitor;

[0046] 532. Third power switch;

[0047] 533. Fourth power switch;

[0048] 902. Computer equipment;

[0049] 904, Processor;

[0050] 906. Memory;

[0051] 908. Drive mechanism;

[0052] 910. Input / Output Module;

[0053] 912. Input devices;

[0054] 914. Output devices;

[0055] 916. Presentation equipment;

[0056] 918. Graphical User Interface;

[0057] 920. Network interface;

[0058] 922. Communication link;

[0059] 924. Communication bus. Detailed Implementation

[0060] The technical solutions in the embodiments described below will be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments described herein, and not all of the embodiments. Based on the embodiments described herein, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this document.

[0061] It should be noted that the terms "first," "second," etc., used in the specification, claims, and accompanying drawings herein are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, apparatus, product, or device that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or devices.

[0062] With the increasing number of applications of solar energy, effectively increasing the output power of solar cells is an important direction in photovoltaic research. Among these technologies, the Maximum Power Point Tracking (MPPT) control device is currently an important device for controlling the output power of solar energy. The MPPT control device achieves maximum power point tracking by setting up a DC-DC converter. The solar cell converts solar energy into electrical energy for storage, and the voltage is converted by the converter to output to the load (electrical equipment). However, since the input and output voltages of the DC-DC converter cannot be directly controlled, the output voltage is uncontrollable, making it difficult to provide a continuous and stable voltage to the load, thus affecting its normal operation.

[0063] To address the aforementioned issues, this specification provides an MPPT control device for solar panels. This device achieves dual closed-loop control of the converter's input and output voltages by setting two closed-loop control circuits at the input and output terminals of the converter. This enables accurate control of the converter's operation, improving the stability of the solar panel's maximum power point tracking and the stability of the converter's output voltage.

[0064] In the embodiments described in this specification, such as Figure 1 and Figure 4The diagram shows the structure of the MPPT control device for a solar panel. The device includes a sampling module 200, a calculation module 300, an adjustment module 400, and a conversion module 500. The sampling module 200 is used to collect the previous cycle output voltage and output current of the solar panel 100, as well as the previous cycle output voltage of the conversion module 500. The calculation module 300 is used to obtain the previous cycle output voltage and output current of the solar panel 100, and calculate the current cycle input voltage reference value of the conversion module 500 according to a preset algorithm. The adjustment module 400 is used to obtain the current cycle input voltage parameter of the conversion module 500 according to the previous cycle output voltage of the solar panel 100, the previous cycle output voltage of the conversion module 500, and the current cycle input voltage reference value of the conversion module 500, through a preset adjustment rule. The conversion module 500 is used to perform voltage conversion on the previous cycle output voltage of the solar panel 100 according to the current cycle input voltage parameter to achieve maximum power point tracking of the solar panel 100.

[0065] The input voltage reference value of the current cycle converter module 500 is calculated based on the output voltage and output current of the solar panel in the previous cycle, which is the output voltage reference value of the solar panel 100. The output voltage reference value of the solar panel 100 is the output voltage value of the solar panel 100 that can track the maximum power point, obtained according to the MPPT algorithm. In order to achieve controllable and stable control of the actual voltage and output voltage reference value of the solar panel 100, a series PI controller can be designed to control the input voltage and output voltage of the converter, thereby ensuring the stability of the converter output voltage.

[0066] The solar panel 100 can convert solar energy into electrical energy and also output electrical energy to a load to ensure the load's normal power supply. The load is an electrical device, which can be a device equipped with solar cells. The solar panel 100 can also have other forms, such as a solar cell array. Different array numbers can be set according to energy storage requirements. The specific setting method is not limited in this specification.

[0067] To improve the battery life of electrical equipment, such as in low-light conditions, an energy storage module can be installed at the output of the converter to store the electrical energy converted by the solar panel 100, which can extend the working time of the electrical equipment in low-light conditions.

[0068] The sampling module 200 can be a sampling circuit connected to the input and output terminals of the conversion module 500. It can collect the output voltage and output current of the solar panel 100 and the output voltage of the conversion module 500, and can generate a parameter form that can be recognized by the calculation module 300 according to a preset conversion rule. The specific conversion rule is not limited in this specification.

[0069] In practical applications, the sampling circuit can acquire data in real time, improving the accuracy of maximum power point tracking, increasing converter control efficiency, and preventing excessive conversion voltage. However, this requires the calculation module to perform real-time calculations, thus necessitating significant computational power. In some other embodiments, the sampling circuit can also acquire data periodically, reducing the computational burden on the calculation module and allowing the entire control device to operate with high safety and performance. For example, multiple acquisition time points can be set within a preset period, and the average of these multiple acquisition values ​​can be used as the acquisition data for the current period, ensuring data reliability and reducing the impact of abnormal data. Alternatively, a single acquisition point can be set within a preset period, such as one of the preset period's start time, middle time, or end time. Using this single-point data as the acquisition data for the current period ensures data authenticity and reliability, thereby achieving rapid maximum power point tracking.

[0070] The calculation module 300 can be an MPPT controller, which has an internal MPPT algorithm. It can calculate the current output power of the solar panel 100 based on the output voltage and output current of the solar panel 100. That is, it can calculate the previous cycle output power of the solar panel 100 based on the previous cycle output voltage and output current of the solar panel 100, and determine the position of the current power point on the power curve. Based on the previous cycle output power, the current cycle output voltage of the solar panel 100 is calculated, which is the current cycle input voltage reference value of the conversion module 500. Optionally, the specific calculation method can be: constant voltage tracking method, incremental conductance method, and disturbance observation method.

[0071] Taking the perturbation observation method as an example, its principle is to determine whether to increase or decrease the operating voltage of the solar panel 100 by comparing the output power of the solar panel 100 in the current cycle with the output power in the previous cycle.

[0072] Suppose that at a certain time t1, the output power of the solar panel is P1. The converter operates, increasing the operating voltage of the solar panel by ΔV. After a period of time Δt, at time t2 (t2 = t1 + Δt), the output power of the solar panel is detected to be P2. If ΔP (ΔP = P1 - P2) is positive, the operating voltage of the solar panel should continue to increase by ΔV until ΔP = 0; if ΔP is negative, the operating voltage of the solar panel should decrease by ΔV until ΔP = 0.

[0073] A suitable value should be selected for ΔV. If ΔV is too large, the output of the solar panel will fluctuate around the maximum power point; if ΔV is too small, although tracking accuracy can be guaranteed, more time is required, and the effect will deteriorate when the maximum power point changes frequently. Through continuous perturbation and comparison, the output of the solar array is gradually made to approach the maximum power point, and eventually stabilizes near the maximum power point.

[0074] In a further embodiment, the MPPT controller may also be provided with a communication interface for communicating with external devices. The communication interface may be a serial interface, a USB interface, or an application programming interface (API), which can realize communication connection with a host computer or controller. The specific interface type is not limited in this specification.

[0075] like Figure 2 The diagram shows the structure of the adjustment module 400 in this specification. The adjustment module includes a first adjustment unit and a second adjustment unit. The first adjustment unit is used to calculate the current cycle output voltage reference value of the conversion module based on the previous cycle output voltage of the solar panel and the current cycle reference input voltage of the conversion module. The second adjustment unit is used to calculate the current cycle input voltage parameter of the conversion module based on the current cycle output voltage reference value of the conversion module and the previous cycle output voltage of the conversion module.

[0076] In practical applications, both the first adjustment unit and the second adjustment unit are PI controllers, such as... Figure 3The diagram shown is a framework diagram of the dual closed-loop control signal in an embodiment of this specification. Two PI controllers are connected in series. The first adjustment unit, i.e., the first PI controller, is set in the main input voltage control loop to adjust the output voltage of the solar panel 100 (i.e., the input voltage of the converter). Simultaneously, the second adjustment unit, i.e., the second PI controller, is set in the secondary output voltage control loop. Through the adjustment parameters of the first PI controller, it further achieves PI regulation of the converter's output voltage. By implementing dual closed-loop regulation of the converter's input and output voltages, compared to existing PI regulation control that only targets the converter's input voltage, this embodiment of the specification can improve the control of the converter's output voltage, enabling rapid tracking of the solar panel's maximum power point.

[0077] PI control is a type of linear control. It uses the control deviation between the given value and the actual output value to form the control quantity by linearly combining the proportional and integral of the deviation, thereby controlling the controlled object.

[0078] In one specific embodiment, the working principle of the first PI controller can be as follows:

[0079] The MPPT controller acquires the output voltage and current of the solar panel, calculates the current output power of the solar panel based on the preset MPPT algorithm, determines the position of the current power point on the power curve, and then calculates the reference input voltage V of the converter module. PV_REF PI regulation, which uses a reference input voltage and the actual input voltage (i.e., the output voltage of the solar panel), is an adjustment in the main control circuit for the output voltage of the solar panel.

[0080] The first PI controller controls the input voltage (previous cycle input voltage) in the main circuit based on the input voltage. PV_FBK and reference input voltage V PV_REF Subtracting the values ​​yields the deviation value V. PV_ERR The first PI controller is based on the deviation value V PV_ERR The output voltage reference value V of the converter module is calculated using a PI control law. OUT_REF This ensures that the converter's output voltage to the load gradually approaches the maximum power point, wherein the output voltage reference value V OUT_REF The following calculation formula (1) is used to obtain:

[0081]

[0082] Where K P1 K is the first proportional parameter for the current period. I1 u is the first integral parameter for the current period. p1 The first proportional term of the output voltage in the current cycle, ui1 u is the first integral term of the output voltage in the current cycle. i1-1 This is the first integral term of the output voltage from the previous cycle. The first proportional parameter and the first integral parameter are configured according to actual operating conditions. The specific values ​​can be tuned using an engineering trial-and-error method, employing a proportional-then-integral tuning procedure to tune the parameters of the first PI controller in the main input voltage circuit. Optionally, the parameters of the first PI controller in the main input voltage circuit are: K P1 =-1.15, K I1 =0.15. In other embodiments, the first proportional parameter and the first integral parameter can also be obtained in other ways, which are not limited in the embodiments of this specification.

[0083] It should be noted that the input term (V) of the first PI controller PV_ERR ) and output items (V OUT_REF All input and output data need to be homogenized to ensure their reliability.

[0084] The working principle of the second PI controller can be as follows: Based on the above-mentioned PI control of the input voltage of the conversion module, the output voltage reference value V is calculated by the first PI controller. OUT_REF The output voltage of the conversion module (i.e., the output voltage of the previous cycle) V OUT_FBK The final output voltage of the PI regulation control module is adjusted on the secondary circuit of the output voltage control module.

[0085] Specifically, the second PI controller is based on the output voltage reference value V. OUT_REF The output voltage of the conversion module (output voltage of the previous cycle) V OUT_FBK Subtracting the values ​​yields the deviation value V. OUT_ERR The second PI controller is based on the deviation value V OUT_ERR The input voltage parameters for the current cycle, i.e., the duty cycle D of the converter module, are calculated using the PI control law. The duty cycle D is obtained by the following formula (2):

[0086]

[0087] Where K P2 K is the second proportional parameter for the current period. I2 u is the second integral parameter for the current period. p2 The second proportional term of the output voltage in the current cycle, u i2 u is the second integral term of the output voltage in the current cycle. i2-1This is the second integral term of the output voltage from the previous cycle. The second proportional and second integral parameters are configured according to actual operating conditions. The specific values ​​can be tuned using an engineering trial-and-error method, employing a proportional-then-integral tuning procedure to tune the parameters of the second PI controller in the main input voltage circuit. Optionally, the parameters of the second PI controller in the main input voltage circuit are: K P2 =0.2, K I2 =0.1. In other embodiments, the second proportional parameter and the second integral parameter can also be obtained in other ways, which are not limited in the embodiments of this specification.

[0088] It should be noted that the input term (V) of the second PI controller OUT_ERR Both the input and output items (D) need to be normalized to ensure the reliability of the input and output data.

[0089] In some other embodiments, the first PI controller and the second PI controller may be internal functional modules integrated into the MPPT controller. This reduces the module configuration of the entire device and improves the integration effect of the entire device. The MPPT controller can send corresponding control signals to the converter to achieve rapid control of the converter's output voltage, thereby realizing the tracking of the maximum power point of the solar panel.

[0090] Based on the obtained duty cycle D, the operation of the transformation module can be controlled according to the preset mode allocation rules, which will be further detailed below.

[0091] In the embodiments described in this specification, the conversion module 500 is a DC-DC converter, i.e., a DC-DC converter, such as... Figure 5 The diagram shown is a schematic of the converter. The converter can transform the input voltage according to different operating modes, such as buck mode and boost mode.

[0092] The converter includes a buck switch branch 510, a boost switch branch 530, and a power inductor 520; the input terminal of the buck switch branch 510 is connected to the output terminal of the solar panel 100, the buck switch branch 510 and the boost switch branch 530 are connected through the power inductor (L1) 520, and the output terminal of the boost switch branch 530 is connected to the load input terminal; the buck switch branch 510 is provided with an input filter capacitor (Cin) 511, and the boost switch branch 530 is provided with an output filter capacitor (Cout) 531.

[0093] Furthermore, the buck switching branch 510 is provided with a first power switch (Q1) 512 and a second power switch (Q2) 513, and the boost switching branch 530 is provided with a third power switch (Q3) 532 and a fourth power switch (Q4) 533; the voltage conversion of the input voltage of the conversion module 500 is achieved by controlling the duty cycles of the first power switch (Q1) 512, the second power switch (Q2) 513, the third power switch (Q3) 532 and the fourth power switch (Q4) 533.

[0094] Among them, the buck switching branch 510 realizes the buck processing of the input voltage, the boost switching branch 530 realizes the boost processing of the input voltage, the middle node of the buck switching branch 510 is connected to the middle node of the boost switching branch 530 through a power inductor 520, forming a four-switch Buck-Boost circuit. The input filter capacitor 511 is connected in parallel at both ends of the buck switching branch 510 to filter the input current; the output filter capacitor 531 is connected in parallel at both ends of the boost switching branch to filter the output current. In actual operation, the regulation of the input voltage is achieved by controlling the power switches.

[0095] As Figure 6 shown, it is a schematic diagram of the equivalent circuit of the buck mode of the converter. That is, when Vin > Vout, the converter works in the buck mode. The power switches Q1 and Q2 form the buck switching branch and are in an alternating switching state. The duty cycle of the power switch Q1 and the duty cycle of the power switch Q2 are in anti-phase; the power switch Q3 remains off and the power switch Q4 remains on, and the reduction of the output voltage can be achieved.

[0096] As Figure 7 shown, it is a schematic diagram of the equivalent circuit of the boost mode of the converter. That is, when Vin < Vout, the converter works in the boost mode. The power switches Q3 and Q4 form the boost switching branch and are in an alternating switching state. The duty cycle of the power switch Q3 and the duty cycle of the power switch Q4 are in anti-phase; the power switch Q1 remains on and the power switch Q2 remains off, and the increase of the output voltage can be achieved.

[0097] When Vin ≈ Vout, Q1, Q2, Q3, and Q4 are all in the switching state, and the transition between the buck mode and the boost mode is completed smoothly and smoothly. At this time, the duty cycle of the power switch Q1 and the duty cycle of the power switch Q2 are in anti-phase, and the duty cycle of the power switch Q3 and the duty cycle of the power switch Q4 are in anti-phase.

[0098] In the embodiments of this specification, the first power switch (Q1) 512, the second power switch (Q2) 513, the third power switch (Q3) 532, and the fourth power switch (Q4) 533 are all gallium nitride (GaN) power switches. Compared with traditional silicon (Si) devices, gallium nitride devices have superior switching and conduction characteristics. Using GaN power switches can significantly increase the circuit switching frequency, maintain high efficiency while increasing power density, and thus ensure fast tracking of the maximum power point.

[0099] In the embodiments of this specification, the MPPT controller controls the duty cycle of the converter through a pulse width modulation (PWM) signal. Since the PWM signal generated by the MPPT controller is relatively weak, especially the duty cycle signal obtained through the PI controller is small, it is difficult to efficiently control the GaN power switch in the converter. Therefore, the MPPT control device can also be equipped with a drive module. The drive module is used to drive the converter module to work according to the duty cycle. The signal can be amplified by adjusting the pulse amplitude of the PWM signal. Optionally, the drive module can be a driver. By amplifying the PWM signal and applying it to the power switch, it causes a change in the circuit operating state, thereby driving the power to turn the switch on and off, achieving maximum power point tracking. Optionally, the driver can be a GaN driver, which can improve the circuit switching efficiency and the maximum power point tracking efficiency.

[0100] Based on the converter's duty cycle D obtained by the PI controller, the MPPT controller, combined with a specific mode allocation method, can realize the operation control of the converter. In the embodiments of this specification, one method of converter operating mode and duty cycle allocation is shown in Table 1 below:

[0101] Table 1 Calculation of Working Mode and Duty Cycle

[0102]

[0103] Where D Q1 D Q2 D Q3 and D Q4 D represents the duty cycle of the four power switches in the converter. G_BuckMasx D GC-BoostMax and D GC_BuckMax The boundary values ​​for different modes need to be determined experimentally, based on the actual converter structure and operating conditions. This specification does not impose any limitations on them. C1 D C2 D C3 D C_Boost and D C_BuckThe duty cycle adjustment parameters for different power switches need to be determined through experiments and are not limited in this manual.

[0104] As shown in Table 1, in order to smoothly complete the transition between boost and buck modes, the control range of the buck-boost converter is divided into four operating modes: buck, constant boost-buck, constant buck-boost, and boost. The duty cycle is calculated for each mode to make the gain of buck and boost modes monotonically increase.

[0105] Specifically, when the duty cycle D is less than D G_BuckMasx At this time, the DC-DC converter operates in buck mode, with power switch Q1 having a duty cycle of D and power switch Q3 having a duty cycle of 0. When the duty cycle D is greater than D... G-BuckMax Less than D GC-BoostMax At this time, the DC-DC converter operates in constant boost-buck mode, and the duty cycle of power switch Q1 is DD. C1 The duty cycle of power switch Q3 is a fixed value D. C_Boost When the duty cycle D is greater than D GC_BoostMax Less than D GC_BuckMax At this time, the DC-DC converter operates in constant buck-boost mode, and the duty cycle of power switch Q1 is a fixed value D. C_Buck The duty cycle of power switch Q3 is DD. C2 When the duty cycle D is greater than D GC_BuckMax At this time, the DC-DC converter operates in boost mode, the duty cycle of power switch Q1 is fixed at 1, and the duty cycle of power switch Q3 is DD. C3 The duty cycles of power switches Q1 and Q2 are reversed, and the duty cycles of Q3 and Q4 are reversed, i.e., D... Q2 =1-D Q1 D Q4 =1-D Q3 .

[0106] In one specific embodiment, D G_BuckMasx It is 0.9, D GC-BoostMax For 0.95 and D GC_BuckMaxThe duty cycle is 1.05. Since the PI controller output range is 0-1, the output duty cycle can be increased to facilitate the allocation of the duty cycle D. For example, doubling the value can be used as the duty cycle D, resulting in a duty cycle range of 0-2. When the duty cycle D is less than 0.9, the DC-DC converter operates in buck mode, with power switch Q1 having a duty cycle of D and power switch Q3 having a duty cycle of 0. When the duty cycle D is greater than 0.9 but less than 0.95, the DC-DC converter operates in constant boost-buck mode, with power switch Q1 having a duty cycle of D-0.03 and power switch Q3 having a fixed duty cycle of 0.07. When the duty cycle D is greater than 0.95 but less than 1.05, the DC-DC converter operates in constant buck-boost mode, with power switch Q1 having a fixed duty cycle of 0.92 and power switch Q3 having a duty cycle of D-0.87. When the duty cycle D is greater than 1.05, the DC-DC converter operates in boost mode, the duty cycle of power switch Q1 is fixed at 1, and the duty cycle of power switch Q3 is D-0.96. The above is one embodiment of the converter's operating mode and duty cycle allocation in this specification. Other embodiments may have different forms, which are not limited in this specification.

[0107] It should be noted that the converter's operating mode and the allocation of the power switch duty cycle can also be set internally within the MPPT controller. The MPPT controller adjusts the operating mode and allocates the power switch duty cycle. Then, the output duty cycle allocation signal is amplified by the GaN driver and applied to the GaN power switch. Changes in the power switch duty cycle cause changes in the circuit's operating state, thereby affecting V. PV and V OUT The changes occur, thereby controlling the output voltage for the current cycle. This process is repeated in subsequent cycles, allowing the solar panel to gradually approach its maximum power point.

[0108] In the embodiments of this specification, since the converter is constantly in operation, in order to improve its operational safety, the device may also be equipped with a temperature sensor. The temperature sensor is positioned close to the converter and can acquire the converter's operating temperature in real time. Preferably, it is positioned near the power switch of the converter and can collect the temperature information of the power switch. The MPPT controller can also obtain the data collected by the temperature sensor and determine whether the converter's operating temperature exceeds the preset temperature threshold. If it exceeds the preset temperature threshold, the power switch is controlled to turn off. When the converter dissipates heat to below the preset temperature threshold, the converter continues to operate.

[0109] Based on the MPPT control device for solar panels provided above, this specification also provides an MPPT control method for solar panels, such as... Figure 8 The diagram illustrates the steps of an MPPT control method for a solar panel according to an embodiment of this specification. This specification provides the operational steps of the method described in the embodiments or flowcharts, but based on conventional or non-inventive methods, more or fewer operational steps may be included. The order of steps listed in the embodiments is merely one possible execution order among many and does not represent the only possible execution order. In actual system or device products, the methods shown in the embodiments or drawings can be executed sequentially or in parallel. Specifically, as shown... Figure 8 As shown, the method may include:

[0110] S101: Obtain the previous cycle output voltage and output current of the solar panel, as well as the previous cycle output voltage of the conversion module;

[0111] S102: Based on the previous cycle output voltage and previous cycle output current of the solar panel, the current cycle input voltage reference value of the conversion module is calculated using a preset algorithm;

[0112] S103: Based on the previous cycle output voltage of the solar panel, the previous cycle output voltage of the conversion module, and the current cycle input voltage reference value of the conversion module, the current cycle input voltage parameter of the conversion module is obtained through a preset adjustment rule;

[0113] S104: Based on the current cycle input voltage parameters, perform voltage transformation on the previous cycle output voltage of the solar panel, and determine whether the current cycle output power of the solar panel has reached the maximum power point;

[0114] S105: If the current cycle output power of the solar panel does not reach the maximum power point, the steps of obtaining the output power of the solar panel are repeated to achieve maximum power point tracking of the solar panel.

[0115] The embodiments in this specification achieve stable control of the solar panel output voltage and the converter output voltage by implementing closed-loop control at both the input and output terminals of the converter. This enables rapid and stable tracking of the solar panel's maximum power point. Furthermore, the embodiments in this specification use GaN devices as power switches and drivers, which enables high-frequency power conversion of the converter. While ensuring high efficiency, this achieves better power density and allows the solar panel to approach its maximum power point more quickly.

[0116] This specification also provides an embodiment of a device equipped with a solar panel and the MPPT control device for the solar panel described above. The device can be a solar-powered drone or other device that can operate on the ground or in the air, or it can be a household or commercial device, and is not limited in this specification.

[0117] In a further embodiment, such as Figure 9 As shown in this embodiment, a computer device 902 may include one or more processors 904, such as one or more central processing units (CPUs), each of which can implement one or more hardware threads. The computer device 902 may also include any memory 906 for storing information of any kind, such as code, settings, data, etc. Non-limitingly, for example, the memory 906 may include any type of RAM, any type of ROM, flash memory, hard disk, optical disk, etc. More generally, any memory can use any technology to store information. Further, any memory can provide volatile or non-volatile retention of information. Further, any memory can represent a fixed or removable component of the computer device 902. In one case, when the processor 904 executes associated instructions stored in any memory or combination of memories, the computer device 902 can perform any operation of the associated instructions. The computer device 902 also includes one or more drive mechanisms 908 for interacting with any memory, such as hard disk drive mechanisms, optical disk drive mechanisms, etc.

[0118] Computer device 902 may also include an input / output module 910 (I / O) for receiving various inputs (via input device 912) and providing various outputs (via output device 914). A specific output mechanism may include a presentation device 916 and an associated graphical user interface 918 (GUI). In other embodiments, the input / output module 910 (I / O), input device 912, and output device 914 may be omitted, and the device may function solely as a computer device within a network. Computer device 902 may also include one or more network interfaces 920 for exchanging data with other devices via one or more communication links 922. One or more communication buses 924 couple the components described above together.

[0119] Communication link 922 can be implemented in any way, such as via a local area network (LAN), a wide area network (WAN) (e.g., the Internet), a point-to-point connection, or any combination thereof. Communication link 922 may include any combination of hardwired links, wireless links, routers, gateway functions, name servers, etc., governed by any protocol or combination of protocols.

[0120] Corresponding to Figure 8In addition to the methods described above, this embodiment also provides a computer-readable storage medium storing a computer program that, when executed by a processor, performs the steps of the above-described methods.

[0121] This embodiment also provides a computer-readable instruction, wherein when a processor executes the instruction, the program therein causes the processor to perform the following: Figure 8 The method shown.

[0122] It should be understood that in the various embodiments of this document, the sequence number of each process does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this document.

[0123] It should also be understood that, in the embodiments herein, the term "and / or" is merely a description of the relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following associated objects have an "or" relationship.

[0124] Those skilled in the art will 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 implementation should not be considered beyond the scope of this document.

[0125] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0126] In the embodiments provided herein, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the couplings or direct couplings or communication connections shown or discussed may be indirect couplings or communication connections through some interfaces, devices, or units, or they may be electrical, mechanical, or other forms of connection.

[0127] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of the embodiments described herein, depending on actual needs.

[0128] Furthermore, the functional units in the various embodiments of this document can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0129] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this paper, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this paper. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0130] This document uses specific embodiments to illustrate the principles and implementation methods of this document. The descriptions of the embodiments above are only for the purpose of helping to understand the methods and core ideas of this document. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this document. Therefore, the content of this specification should not be construed as a limitation of this document.

Claims

1. An MPPT control device for solar panels, characterized in that, The device includes a sampling module, a calculation module, an adjustment module, and a transformation module; The sampling module is used to collect the previous cycle output voltage and previous cycle output current of the solar panel, as well as the previous cycle output voltage of the conversion module. The calculation module is used to obtain the previous cycle output voltage and previous cycle output current of the solar panel, and calculate the current cycle input voltage reference value of the conversion module according to a preset algorithm. Specifically, it includes: calculating the previous cycle output power of the solar panel based on the previous cycle output voltage and previous cycle output current of the solar panel, determining the position of the current power point on the power curve, and calculating the current cycle input voltage reference value of the conversion module based on the previous cycle output power. The calculation method is: constant voltage tracking method, incremental conductance method or perturbation observation method. The adjustment module is used to obtain the current cycle input voltage parameter of the conversion module according to the previous cycle output voltage of the solar panel, the previous cycle output voltage of the conversion module, and the current cycle input voltage reference value of the conversion module through a preset adjustment rule; the adjustment module includes a first adjustment unit and a second adjustment unit; both the first adjustment unit and the second adjustment unit are PI controllers; the first adjustment unit is used to calculate the current cycle output voltage reference value of the conversion module according to the previous cycle output voltage of the solar panel and the current cycle reference input voltage of the conversion module through a PI control law; the second adjustment unit is used to calculate the current cycle input voltage parameter of the conversion module according to the current cycle output voltage reference value of the conversion module and the previous cycle output voltage of the conversion module through a PI control law; The conversion module is used to convert the output voltage of the solar panel in the previous cycle according to the current cycle input voltage parameters, so as to realize the maximum power point tracking of the solar panel.

2. The MPPT control device according to claim 1, characterized in that, The device further includes a drive module, which drives the conversion module to work according to the current cycle input voltage parameters.

3. The MPPT control device according to claim 2, characterized in that, The conversion module includes a buck switch branch, a boost switch branch, and a power inductor; The input terminal of the step-down switch branch is connected to the output terminal of the solar panel, the step-down switch branch and the boost switch branch are connected through the power inductor, and the output terminal of the boost switch branch is connected to the load input terminal. The step-down switch branch is equipped with an input filter capacitor, and the step-up switch branch is equipped with an output filter capacitor.

4. The MPPT control device according to claim 3, characterized in that, The step-down switch branch is provided with a first power switch and a second power switch, and the step-up switch branch is provided with a third power switch and a fourth power switch; the voltage conversion of the input voltage of the conversion module is realized by controlling the first power switch, the second power switch, the third power switch and the fourth power switch.

5. The MPPT control device according to claim 4, characterized in that, The first power switch, the second power switch, the third power switch, and the fourth power switch are all gallium nitride power switches; the driving module is a gallium nitride driver.

6. The MPPT control device according to claim 1, characterized in that, The device also includes a temperature module, which is used to obtain the operating temperature of the conversion module.

7. An MPPT control method for solar panels, characterized in that, The method includes: Obtain the previous cycle output voltage and output current of the solar panel, as well as the previous cycle output voltage of the conversion module; Based on the previous cycle output voltage and previous cycle output current of the solar panel, the reference value of the current cycle input voltage of the conversion module is calculated by a preset algorithm. Specifically, this includes: calculating the previous cycle output power of the solar panel based on the previous cycle output voltage and previous cycle output current, determining the position of the current power point on the power curve, and calculating the reference value of the current cycle input voltage of the conversion module based on the previous cycle output power. The calculation method is: constant voltage tracking method, incremental conductance method, or disturbance observation method. Based on the previous cycle output voltage of the solar panel, the previous cycle output voltage of the converter module, and the current cycle input voltage reference value of the converter module, the current cycle input voltage parameter of the converter module is obtained through a preset adjustment rule. Specifically, this includes: calculating the current cycle output voltage reference value of the converter module using a PI control law based on the previous cycle output voltage of the solar panel and the current cycle reference input voltage of the converter module; and calculating the current cycle input voltage parameter of the converter module using a PI control law based on the current cycle output voltage reference value of the converter module and the previous cycle output voltage of the converter module. Based on the current cycle input voltage parameters, the output voltage of the solar panel in the previous cycle is transformed, and it is determined whether the current cycle output power of the solar panel has reached the maximum power point. If the current cycle output power of the solar panel does not reach the maximum power point, the steps of obtaining the output power of the solar panel are repeated to achieve maximum power point tracking of the solar panel.

8. A device, characterized in that, The device includes a solar panel, and the device further includes the MPPT control device for the solar panel as described in any one of claims 1 to 6.

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