MPPT calculation method, device and computer equipment

Abstract

The present application provides an MPPT calculation method, device and computer equipment, including: first obtaining the on-time of the power switch tube in the boost circuit within the target sampling period; and sampling the intermediate value of the inductor current during the on-time of the power switch tube; then obtaining the photovoltaic input voltage and the bus voltage, and obtaining the off-time of the power switch tube within the target sampling period according to the photovoltaic input voltage and the bus voltage; finally, according to the intermediate value of the inductor current, the on-time and the off-time in the boost circuit, obtaining the equivalent average current within the target sampling period, and achieving the maximum power output according to the equivalent average current. In the above scheme, when the current at the inductor is discontinuous, sampling the intermediate value of the inductor current can accurately find the maximum power point, effectively improve the static MPPT and dynamic MPPT of the photovoltaic, and achieve the maximum benefit of photovoltaic energy.

Description

Technical Field

[0001] The present application relates to the technical field of inverters, and in particular to an MPPT calculation method, device and computer equipment. Background Art

[0002] With energy shortages and the rapid development of the new energy industry, the technical indicators of new energy control systems are becoming increasingly higher, and there are also higher requirements for the maximum power point tracking (MPPT) of photovoltaic panels.

[0003] At present, the commonly used maximum power point tracking algorithms include constant voltage method, perturbation observation method, hill climbing method, admittance increment method, fuzzy logic control method, etc. These methods all need to sample the output voltage Upv(k) and output current Ipv(k) of the photovoltaic array in the current control cycle, and then calculate the power Ppv(k) of the current control cycle, and deduce the photovoltaic voltage direction of the next photovoltaic array output energy through prediction, comparison and other methods. Among them, the output current Ipv(k) sampling of the photovoltaic array is generally the instantaneous value of the current at the boost inductor or the filtered value of the instantaneous value. The system in which the MPPT works is a boost circuit. In the boost circuit, when the boost works, the current at the inductor has two situations: continuous and discontinuous. When the current at the inductor is continuous, the above-mentioned sampled current is accurate, and when the current at the inductor is discontinuous, the above-mentioned sampled current is not the average current of the entire operation, but only a relative current.

[0004] Therefore, in the above scheme, when the current at the inductor is intermittent, the sampled current has a deviation in the entire calculation cycle, and the existence of this deviation will cause the MPPT to shift, thereby failing to achieve the maximization of power and energy. Summary of the invention

[0005] The present application provides an MPPT calculation method, device and computer equipment, which can accurately find the maximum power point when the current at the inductor is discontinuous, effectively improve the static MPPT and dynamic MPPT of photovoltaics, and achieve the maximum benefit of photovoltaic energy. The technical solution is as follows.

[0006] On the one hand, a MPPT calculation method is provided, the method is applied to a boost circuit, the boost circuit includes a photovoltaic array, an inductor and a power switch tube;

[0007] The method comprises:

[0008] Obtaining the on-time Ton of the power switch tube in the boost circuit within a target sampling period;

[0009] During the on-time Ton of the power switch tube, sampling the middle value of the inductor current;

[0010] Acquire a photovoltaic input voltage and a bus voltage, and acquire a turn-off time Toff of the power switch tube within a target sampling period according to the photovoltaic input voltage and the bus voltage;

[0011] Obtaining an equivalent average current within the target sampling period according to the intermediate value of the inductor current in the boost circuit, the on-time Ton, and the off-time Toff;

[0012] According to the equivalent average current, maximum power output is achieved.

[0013] In another aspect, there is provided an MPPT calculation device, the device comprising:

[0014] A conduction time acquisition module, used to obtain the conduction time Ton of the power switch tube in the boost circuit within a target sampling period;

[0015] An inductor current intermediate value sampling module is used to sample the inductor current intermediate value within the conduction time Ton of the power switch tube;

[0016] A turn-off time acquisition module, used to acquire a photovoltaic input voltage and a bus voltage, and acquire a turn-off time Toff of the power switch tube within a target sampling period according to the photovoltaic input voltage and the bus voltage;

[0017] An equivalent average current acquisition module, used to acquire the equivalent average current within the target sampling period according to the intermediate value of the inductor current in the boost circuit, the on time Ton and the off time Toff;

[0018] The maximum power output module is used to achieve maximum power output according to the equivalent average current.

[0019] In a possible implementation manner, the inductor current intermediate value sampling module is further used for:

[0020] The current variation ΔI within the on-time Ton of the power switch tube is obtained, and based on the current variation ΔI, the intermediate value of the inductor current within the on-time Ton of the power switch tube is obtained.

[0021] In a possible implementation manner, the off time acquisition module is further used to:

[0022] The off time Toff of the power switch tube within the target sampling period is obtained by the following formula:

[0023] Toff=L*△I / (U bus -U pv );

[0024] Wherein, L represents the inductance value, △I represents the current change during the conduction time Ton of the power switch tube, and U bus Indicates bus voltage, U pv Indicates the photovoltaic input voltage.

[0025] In a possible implementation manner, the equivalent average current acquisition module is further used to:

[0026] Obtaining a first product of the intermediate value of the inductor current and the on-time Ton;

[0027] Obtaining a second product of the intermediate value of the inductor current and the off time Toff;

[0028] The equivalent average current within the target sampling period is obtained according to the ratio between the sum of the first product and the second product and the target sampling period value.

[0029] In a possible implementation manner, the device is further used for:

[0030] The equivalent average current within the target sampling period is deduced again by the following formula to obtain the final equivalent average current:

[0031] I av 1=(Ipv*Ton+2*Ipv*L*Ipv / (U bus -U pv )) / Ts;

[0032] Among them, I av1 represents the final equivalent average current within the target sampling period, Ts represents the target sampling period value, L represents the inductance value, Ipv represents the intermediate value of the inductor current, U bus Indicates bus voltage, U pv Indicates the photovoltaic input voltage.

[0033] In a possible implementation manner, the maximum power output module is further used for:

[0034] The maximum power point voltage is obtained through MPPT calculation according to the photovoltaic input voltage and the equivalent average current.

[0035] In a possible implementation manner, the device is further used for:

[0036] The maximum power point voltage is controlled by a PI controller with an outer voltage loop and an inner current loop to provide drive for the boost circuit.

[0037] On the other hand, a computer device is provided, comprising a processor and a memory, wherein the memory stores at least one instruction, and the at least one instruction is loaded and executed by the processor to implement an MPPT calculation method as described above.

[0038] On the other hand, a computer-readable storage medium is provided, wherein at least one instruction is stored in the storage medium, and the at least one instruction is loaded and executed by a processor to implement an MPPT calculation method as described above.

[0039] The technical solution provided by this application may have the following beneficial effects:

[0040] First, the on-time Ton of the power switch tube in the boost circuit within the target sampling period is obtained; and the intermediate value of the inductor current is sampled within the on-time Ton of the power switch tube; then the photovoltaic input voltage and the bus voltage are obtained, and the off-time Toff of the power switch tube within the target sampling period is obtained according to the photovoltaic input voltage and the bus voltage; finally, according to the intermediate value of the inductor current in the boost circuit, the on-time Ton and the off-time Toff, the equivalent average current within the target sampling period is obtained, and according to the equivalent average current, the maximum power output is achieved.

[0041] In the above scheme, when the current at the inductor is intermittent, the intermediate value of the inductor current is sampled, and the actual value of the inductor current, that is, the equivalent average current, is calculated using the simulation algorithm of the inductor formula, thereby achieving accurate calculation of the inductor current, being able to accurately find the maximum power point, and realizing the MPPT calculation method, effectively improving the static MPPT and dynamic MPPT of photovoltaics, and ultimately achieving the maximum benefit of photovoltaic energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0043] Figure 1 The figure is a schematic structural diagram of a boost circuit according to an exemplary embodiment.

[0044] Figure 2 is a flow chart of an MPPT control system according to an exemplary embodiment.

[0045] Figure 3It is a schematic diagram of a waveform of a continuous inductor current output by a boost circuit when working according to an exemplary embodiment.

[0046] Figure 4 It is a schematic diagram of a waveform of a discontinuous inductor current output by a boost circuit when working according to an exemplary embodiment.

[0047] Figure 5 The figure is a flow chart of a method for calculating an MPPT according to an exemplary embodiment.

[0048] Figure 6 It is a schematic diagram of various calculation parameters within a target sampling period when the inductor current is discontinuous according to an exemplary embodiment.

[0049] Figure 7 It is a structural block diagram of an MPPT calculation device according to an exemplary embodiment.

[0050] Figure 8 A structural block diagram of a computer device shown in an exemplary embodiment of the present application is shown. DETAILED DESCRIPTION

[0051] The technical solution of the present application will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0052] It should be understood that in the description of the embodiments of the present application, the term "corresponding" may indicate a direct or indirect correspondence between the two, or an association between the two, or a relationship of indication and being indicated, configuration and being configured, etc.

[0053] Figure 1 The schematic diagram of a boost circuit according to an exemplary embodiment is shown. The boost circuit is also a system for MPPT operation. The boost circuit includes a photovoltaic array, an inductor L1 and a power switch tube T1.

[0054] Further, such as Figure 1 As shown, the battery panel boost circuit also includes an equivalent capacitor C1, a diode D1 and a bus side equivalent capacitor C2.

[0055] Furthermore, the inductor L1 is the boost inductor. At present, the output current of the photovoltaic array is generally sampled by sampling the instantaneous value of the current at the boost inductor or the filtered value of the instantaneous value. The current output by the photovoltaic array is respectively connected to the equivalent capacitor C1, the inductor L1, the diode D1, the power switch tube T1 and the bus side equivalent capacitor C2, such as Figure 1 As shown, the photovoltaic input voltage of the boost circuit is U pv , the bus side voltage of the boost circuit is U bus , the inductor current at the inductor L1 is Ipv.

[0056] Exemplarily, the power switch tube T1 may be a MOS tube or an IGBT insulated gate bipolar transistor.

[0057] For further information, please refer to Figure 2 The MPPT control system flow chart shown in the figure shows that the MPPT control loop generally samples the voltage Upv(k) and current Ipv(k) of the current control cycle of the photovoltaic array, and gives a given value of the maximum power point voltage of the photovoltaic panel through the MPPT algorithm, and the current photovoltaic array voltage Upv and the inductor current Ipv are controlled through PI to form a voltage loop and a current loop to control the entire photovoltaic MPPT system. In the embodiment, the intermediate value of the inductor current is sampled, and the actual value of the inductor current is calculated using the simulation algorithm of the inductor formula, so as to accurately find the maximum power point to control the entire photovoltaic MPPT system and drive the boost circuit.

[0058] For further information, please refer to Figure 3 The waveform diagram of the continuous inductor current output by the boost circuit when working is shown. Figure 4 The boost circuit shown in FIG. 1 is a schematic diagram of the waveform of the discontinuous inductor current output when the boost circuit is working. Figure 3 As shown, a continuous inductor current waveform, such as Figure 4 As shown in Figure 1, b is the discontinuous inductor current waveform. Figure 3 and Figure 4 In the figure, Ts is the sampling period, Ton is the switch on time, Toff is the switch off time, the carrier uses a symmetrical triangular waveform, the duty cycle comparison value is loaded at the triangular wave period, and the sampling position is sampled when the triangular wave crosses zero. Since a symmetrical triangular wave is used, the value sampled at the zero crossing point is the middle value of the inductor current during the switch T1 on time Ton. Figure 3 It is easy to see from the current waveform diagram in that when the inductor current waveform is continuous, the sampling value is the middle value of the inductor current and also the current average value of the entire sampling period. Even the filtered sampling value can easily maintain accuracy. Figure 4It is easy to see from the current waveform diagram that when the inductor current is intermittent, the sampling value is the middle value of the inductor current, but not the current average value of the entire sampling period. In this way, the filtered sampling value is not easy to maintain accuracy. When running the MPPT algorithm, the sampling error can easily lead to incorrect power calculation, resulting in MPPT deviation. Therefore, the middle value of the inductor current can be sampled, and the actual value of the inductor current can be calculated using the simulation algorithm of the inductor formula, so as to achieve accurate calculation of the inductor current and realize the MPPT operation method.

[0059] Figure 5 is a method flow chart of a MPPT calculation method according to an exemplary embodiment. The method is applied to Figure 1 In the boost circuit shown in FIG. , the boost circuit includes a photovoltaic array, an inductor, and a power switch tube. Figure 5 As shown, the method may include the following steps:

[0060] S501: Obtain the on-time Ton of the power switch tube in the boost circuit within a target sampling period.

[0061] In a possible implementation, when the inductor current in the boost circuit works intermittently, this embodiment samples the intermediate value of the inductor current and uses the simulation algorithm of the inductor formula to calculate the actual value of the inductor current, thereby achieving accurate calculation of the inductor current and realizing MPPT operation. When the boost inductor works, the inductor satisfies the formula: U L =L*di / dt; more precisely, when the switch is turned on, the photovoltaic input voltage U pv Satisfaction: U pv =L*△I / Ton, when the switch is turned off, the bus voltage U bus Satisfaction: U bus =L*△I / Toff. When the inductor current is intermittent, the power switch tube conduction time Ton is output within the target sampling period, and the current is controlled to rise, so as to sample the middle value of the inductor current within the conduction time Ton of the power switch tube.

[0062] S502: sampling the middle value of the inductor current during the on-time Ton of the power switch tube.

[0063] In a possible implementation manner, a current variation ΔI within the on-time Ton of the power switch tube is obtained, and based on the current variation ΔI, an intermediate value of the inductor current within the on-time Ton of the power switch tube is obtained.

[0064] Furthermore, the on-time Ton of the output power switch tube is used to control the current rise. At this time, the sampled intermediate value of the inductor current Ipv=△I / 2; wherein △I represents the current change within the on-time Ton of the power switch tube.

[0065] S503: Obtain a photovoltaic input voltage and a bus voltage, and obtain a turn-off time Toff of the power switch tube within a target sampling period according to the photovoltaic input voltage and the bus voltage.

[0066] In a possible implementation manner, a current change ΔI within a conduction time Ton of the power switch tube is obtained;

[0067] According to the ratio between the current variation ΔI and the target voltage difference, the off time Toff of the power switch tube within the target sampling period is obtained; the target voltage difference is the difference between the bus voltage and the photovoltaic input voltage.

[0068] In a possible implementation manner, the off time Toff of the power switch tube within the target sampling period is obtained by the following formula:

[0069] Toff=L*△I / (U bus -U pv );

[0070] Where, L represents the inductance value, △I represents the current change during the conduction time Ton of the power switch tube, and U bus Indicates bus voltage, U pv Indicates the photovoltaic input voltage.

[0071] Furthermore, due to the presence of the photovoltaic input side capacitor and the bus output side capacitor in the boost circuit, the photovoltaic input voltage U pv and bus voltage U bus The value can be regarded as a fixed value without change, so the turn-off time Toff of the power switch tube can be directly calculated.

[0072] S504: Obtain an equivalent average current within the target sampling period according to the intermediate value of the inductor current in the boost circuit, the on-time Ton, and the off-time Toff.

[0073] In a possible implementation manner, a first product of the intermediate value of the inductor current and the on-time Ton is obtained;

[0074] Obtaining a second product of the middle value of the inductor current and the off time Toff;

[0075] The equivalent average current within the target sampling period is obtained according to the ratio between the sum of the first product and the second product and the target sampling period value.

[0076] In a possible implementation manner, the equivalent average current within the target sampling period is obtained by the following formula:

[0077] I av =(△I*Ton / 2+△I*Toff / 2) / Ts;

[0078] Among them, I av It represents the equivalent average current within the target sampling period, Ts represents the target sampling period value, and △I represents the current change within the conduction time Ton of the power switch tube.

[0079] In a possible implementation manner, the equivalent average current within the target sampling period is deduced again by the following formula to obtain the final equivalent average current:

[0080] I av1 =(Ipv*Ton+2*Ipv*L*Ipv / (U bus -U pv )) / Ts;

[0081] Among them, I av1 represents the final equivalent average current within the target sampling period, Ts represents the target sampling period value, L represents the inductance value, Ipv represents the intermediate value of the inductor current, and U bus Indicates bus voltage, U pv Indicates the photovoltaic input voltage.

[0082] For further information, please refer to Figure 6 The schematic diagram of the calculation parameters within the target sampling period when the inductor current is intermittent is shown, wherein the calculation parameters include the above-mentioned on-time Ton, off-time Toff, the target sampling period value Ts, the inductor current intermediate value △I / 2 and the final equivalent average current I av1 After calculating the equivalent average current within the target sampling period, the inductor current intermediate value Ipv can be obtained by the above-mentioned inductor current intermediate value Ipv: Ipv = △I / 2, and the off time Toff of the power switch tube: Toff = L*△I / (U bus -U pv ) These two formulas are used to further deduce the equivalent average current within the target sampling period to obtain the above-mentioned calculation formula for the final equivalent average current. When the inductor current is intermittent, the final equivalent average current within the target sampling period calculated using the calculation formula for the final equivalent average current participates in the calculation of MPPT, which can accurately find the maximum power point and realize the maximum photovoltaic energy conversion.

[0083] S505: Achieve maximum power output according to the equivalent average current.

[0084] In a possible implementation, the maximum power point voltage is obtained through MPPT calculation according to the photovoltaic input voltage and the equivalent average current.

[0085] In a possible implementation, after calculating the equivalent average current, as Figure 2 As shown, the maximum power point voltage is obtained through MPPT calculation, and the maximum power point voltage is controlled by a PI controller through a voltage outer loop and a current inner loop to provide drive for the boost circuit.

[0086] In summary, the on-time Ton of the power switch tube in the boost circuit within the target sampling period is first obtained; and the intermediate value of the inductor current is sampled within the on-time Ton of the power switch tube; the photovoltaic input voltage and the bus voltage are then obtained, and the off-time Toff of the power switch tube within the target sampling period is obtained according to the photovoltaic input voltage and the bus voltage; finally, the equivalent average current within the target sampling period is obtained according to the intermediate value of the inductor current in the boost circuit, the on-time Ton and the off-time Toff, and the maximum power output is achieved according to the equivalent average current.

[0087] In the above scheme, when the current at the inductor is intermittent, the intermediate value of the inductor current is sampled, and the actual value of the inductor current, that is, the equivalent average current, is calculated using the simulation algorithm of the inductor formula, thereby achieving accurate calculation of the inductor current, being able to accurately find the maximum power point, and realizing the MPPT calculation method, effectively improving the static MPPT and dynamic MPPT of photovoltaics, and ultimately achieving the maximum benefit of photovoltaic energy.

[0088] Figure 7 1 is a block diagram of a MPPT calculation device according to an exemplary embodiment. The device includes:

[0089] The on-time acquisition module 701 is used to acquire the on-time Ton of the power switch tube in the boost circuit within a target sampling period;

[0090] An inductor current intermediate value sampling module 702 is used to sample the inductor current intermediate value during the on-time Ton of the power switch tube;

[0091] The off time acquisition module 703 is used to acquire the photovoltaic input voltage and the bus voltage, and acquire the off time Toff of the power switch tube within the target sampling period according to the photovoltaic input voltage and the bus voltage;

[0092] An equivalent average current acquisition module 704 is used to acquire the equivalent average current within the target sampling period according to the intermediate value of the inductor current in the boost circuit, the on time Ton and the off time Toff;

[0093] The maximum power output module 705 is used to achieve maximum power output according to the equivalent average current.

[0094] In a possible implementation manner, the off time acquisition module 703 is further configured to:

[0095] Obtaining a current change ΔI within the on-time Ton of the power switch tube;

[0096] According to the ratio between the current variation ΔI and the target voltage difference, the off time Toff of the power switch tube within the target sampling period is obtained; the target voltage difference is the difference between the bus voltage and the photovoltaic input voltage.

[0097] In a possible implementation manner, the off time acquisition module 703 is further configured to:

[0098] The off time Toff of the power switch tube within the target sampling period is obtained by the following formula:

[0099] Toff=L*△I / (U bus -U pv );

[0100] Wherein, L represents the inductance value, △I represents the current change during the conduction time Ton of the power switch tube, and U bus Indicates bus voltage, U pv Indicates the photovoltaic input voltage.

[0101] In a possible implementation manner, the equivalent average current acquisition module 704 is further configured to:

[0102] Obtaining a first product of the intermediate value of the inductor current and the on-time Ton;

[0103] Obtaining a second product of the intermediate value of the inductor current and the off time Toff;

[0104] The equivalent average current within the target sampling period is obtained according to the ratio between the sum of the first product and the second product and the target sampling period value.

[0105] In a possible implementation manner, the equivalent average current acquisition module 704 is further configured to: acquire the equivalent average current within the target sampling period by using the following formula:

[0106] Iav =(△I*Ton / 2+△I*Toff / 2) / Ts;

[0107] Among them, I av represents the equivalent average current within the target sampling period, Ts represents the target sampling period value, and ΔI represents the current change within the conduction time Ton of the power switch tube.

[0108] In a possible implementation manner, the device is further used for:

[0109] The equivalent average current within the target sampling period is deduced again by the following formula to obtain the final equivalent average current:

[0110] I av 1=(Ipv*Ton+2*Ipv*L*IpV / (U bus -U pv )) / Ts;

[0111] Among them, I av1 represents the final equivalent average current within the target sampling period, Ts represents the target sampling period value, L represents the inductance value, Ipv represents the intermediate value of the inductor current, U bus Indicates bus voltage, U pv Indicates the photovoltaic input voltage.

[0112] In a possible implementation manner, the maximum power output module 705 is further used for:

[0113] Obtaining a maximum power point voltage through MPPT calculation according to the photovoltaic input voltage and the equivalent average current;

[0114] The device is also used for:

[0115] The maximum power point voltage is controlled by a PI controller with an outer voltage loop and an inner current loop to provide drive for the boost circuit.

[0116] In summary, in the device, the on-time Ton of the power switch tube in the boost circuit within the target sampling period is first obtained; and within the on-time Ton of the power switch tube, the intermediate value of the inductor current is sampled; then the photovoltaic input voltage and the bus voltage are obtained, and according to the photovoltaic input voltage and the bus voltage, the off-time Toff of the power switch tube within the target sampling period is obtained; finally, according to the intermediate value of the inductor current in the boost circuit, the on-time Ton and the off-time Toff, the equivalent average current within the target sampling period is obtained, and according to the equivalent average current, the maximum power output is achieved.

[0117] In the above scheme, when the current at the inductor is intermittent, the intermediate value of the inductor current is sampled, and the actual value of the inductor current, that is, the equivalent average current, is calculated using the simulation algorithm of the inductor formula, thereby achieving accurate calculation of the inductor current, being able to accurately find the maximum power point, and realizing the MPPT calculation method, effectively improving the static MPPT and dynamic MPPT of photovoltaics, and ultimately achieving the maximum benefit of photovoltaic energy.

[0118] See also Figure 8 , which is a structural block diagram of a computer device provided according to an exemplary embodiment of the present application, the computer device includes a memory and a processor, the memory is used to store a computer program, and when the computer program is executed by the processor, the above-mentioned MPPT calculation method is implemented.

[0119] The processor may be a central processing unit (CPU). The processor may also be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or a combination of the above chips.

[0120] As a non-transitory computer-readable storage medium, the memory can be used to store non-transitory software programs, non-transitory computer executable programs and modules, such as program instructions / modules corresponding to the method in the implementation of the present application. The processor executes various functional applications and data processing of the processor by running the non-transitory software programs, instructions and modules stored in the memory, that is, implementing the method in the above method implementation.

[0121] The memory may include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required for at least one function; the data storage area may store data created by the processor, etc. In addition, the memory may include a high-speed random access memory, and may also include a non-transitory memory, such as at least one disk storage device, a flash memory device, or other non-transitory solid-state storage device. In some embodiments, the memory may optionally include a memory remotely disposed relative to the processor, and these remote memories may be connected to the processor via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0122] In an exemplary embodiment, a computer-readable storage medium is also provided, which is used to store at least one computer program, and the at least one computer program is loaded and executed by a processor to implement all or part of the steps in the above method. For example, the computer-readable storage medium can be a read-only memory (ROM), a random access memory (RAM), a compact disc read-only memory (CD-ROM), a magnetic tape, a floppy disk, an optical data storage device, etc.

[0123] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the invention disclosed herein. The present application is intended to cover any modification, use or adaptation of the present application, which follows the general principles of the present application and includes common knowledge or customary techniques in the art that are not disclosed in the present application. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present application are indicated by the following claims.

[0124] It should be understood that the present application is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A MPPT calculation method, characterized in that: The method is applied to a boost circuit, which includes a photovoltaic array, an inductor and a power switch tube; The method comprises: Obtaining the on-time Ton of the power switch tube in the boost circuit within a target sampling period; During the on-time Ton of the power switch tube, sampling the middle value of the inductor current; Acquire a photovoltaic input voltage and a bus voltage, and acquire a turn-off time Toff of the power switch tube within a target sampling period according to the photovoltaic input voltage and the bus voltage; Obtaining an equivalent average current within the target sampling period according to the intermediate value of the inductor current in the boost circuit, the on-time Ton, and the off-time Toff; According to the equivalent average current, a maximum power output is achieved; The sampling of the intermediate value of the inductor current during the on-time Ton of the power switch tube includes: Obtaining a current variation ΔI within the conduction time Ton of the power switch tube, and obtaining an intermediate value of the inductor current within the conduction time Ton of the power switch tube according to the current variation ΔI; The obtaining of the equivalent average current in the target sampling period according to the intermediate value of the inductor current in the boost circuit, the on-time Ton, and the off-time Toff comprises: Obtaining a first product of the intermediate value of the inductor current and the on-time Ton; Obtaining a second product of the intermediate value of the inductor current and the off time Toff; Obtaining an equivalent average current within the target sampling period according to a ratio between a sum of the first product and the second product and a target sampling period value; The step of achieving maximum power output according to the equivalent average current comprises: The maximum power point voltage is obtained through MPPT calculation according to the photovoltaic input voltage and the equivalent average current.

2. The method according to claim 1, characterized in that The off time Toff of the power switch tube within the target sampling period is obtained by the following formula: Toff=L*△I / (U bus -U pv ); Wherein, L represents the inductance value, △I represents the current change during the conduction time Ton of the power switch tube, and U bus Indicates bus voltage, U pv Indicates the photovoltaic input voltage.

3. The method according to claim 1, characterized in that After obtaining the equivalent average current within the target sampling period, the method further includes: The equivalent average current within the target sampling period is deduced again by the following formula to obtain the final equivalent average current: I av1 =(Ipv*Ton+2*Ipv*L*Ipv / (U bus -U pv )) / Ts; Among them, I av1 represents the final equivalent average current within the target sampling period, Ts represents the target sampling period value, L represents the inductance value, Ipv represents the intermediate value of the inductor current, U bus Indicates bus voltage, U pv Indicates the photovoltaic input voltage.

4. The method according to claim 1, characterized in that After achieving maximum power output according to the equivalent average current, the method further includes: The maximum power point voltage is controlled by a PI controller with an outer voltage loop and an inner current loop to provide drive for the boost circuit.

5. An MPPT calculation device, characterized in that: The device comprises: The on-time acquisition module is used to obtain the on-time Ton of the power switch tube in the boost circuit within the target sampling period; An inductor current intermediate value sampling module is used to sample the inductor current intermediate value within the conduction time Ton of the power switch tube; A turn-off time acquisition module, used to acquire a photovoltaic input voltage and a bus voltage, and acquire a turn-off time Toff of the power switch tube within a target sampling period according to the photovoltaic input voltage and the bus voltage; An equivalent average current acquisition module, used to acquire the equivalent average current within the target sampling period according to the intermediate value of the inductor current in the boost circuit, the on time Ton and the off time Toff; A maximum power output module, used to achieve maximum power output according to the equivalent average current; The inductor current intermediate value sampling module is also used for: Obtaining a current variation ΔI within the conduction time Ton of the power switch tube, and obtaining an intermediate value of the inductor current within the conduction time Ton of the power switch tube according to the current variation ΔI; The equivalent average current acquisition module is also used for: Obtaining a first product of the intermediate value of the inductor current and the on-time Ton; Obtaining a second product of the intermediate value of the inductor current and the off time Toff; Obtaining an equivalent average current within the target sampling period according to a ratio between a sum of the first product and the second product and a target sampling period value; The maximum power output module is also used for: The maximum power point voltage is obtained through MPPT calculation according to the photovoltaic input voltage and the equivalent average current.

6. A computer device, characterized in that: The computer device includes a processor and a memory, wherein the memory stores at least one instruction, and the at least one instruction is loaded and executed by the processor to implement an MPPT calculation method as described in any one of claims 1 to 4.

7. A computer-readable storage medium, characterized in that: The storage medium stores at least one instruction, and the at least one instruction is loaded and executed by the processor to implement an MPPT calculation method as described in any one of claims 1 to 4.

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