CN112904929B - Photovoltaic solar system, control method thereof and computer-readable storage medium - Google Patents
Photovoltaic solar system, control method thereof and computer-readable storage medium Download PDFInfo
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Abstract
The invention provides a photovoltaic solar system, a control method thereof and a computer readable storage medium, wherein the method comprises the steps of obtaining the output power and the sampling current of the current sampling period and the last sampling period, and judging whether the working environment is a multi-power extreme environment or not according to the output power and the sampling current of the current sampling period and the last sampling period; if the current working environment is determined to be a multi-power extreme environment, changing the duty ratio of the pulse modulation signal by a preset first step length, calculating the corresponding output power under each duty ratio, searching the target duty ratio of the pulse modulation signal corresponding to the maximum output power, and adjusting the duty ratio of the pulse modulation signal output by the direct-current converter to the target duty ratio. The invention also provides a photovoltaic solar system and a computer-readable storage medium for realizing the method. The invention can quickly search the duty ratio corresponding to the pulse modulation signal corresponding to the maximum value of the output power, and can reduce the production cost of the photovoltaic solar system.
Description
Technical Field
The invention relates to the field of control of photovoltaic solar systems, in particular to a photovoltaic solar system control method, a photovoltaic solar system applying the method and a computer-readable storage medium.
Background
The photovoltaic solar system can convert solar energy into electric energy, is an environment-friendly system utilizing renewable energy, and is gradually widely applied. Photovoltaic solar systems are provided with photovoltaic modules comprising a large number of photovoltaic arrays, which are capable of converting solar energy into direct current. In the mainstream and commercial solar photovoltaic solar system at present, the energy conversion efficiency of the photovoltaic module is not high, and is usually about 20%. However, in practical applications, the actual efficiency of the photovoltaic solar system is lower than that of the photovoltaic module due to the influence of environmental factors, wherein the mismatch problem is the most important reason for the reduction of the energy conversion efficiency of the photovoltaic solar system. The mismatch problem is that the actual voltage-current characteristic of the photovoltaic module is inconsistent with the initially set voltage-current characteristic due to local shielding, dust accumulation coverage, battery aging and the like, so that the efficiency of the photovoltaic solar system is reduced. When the photovoltaic array has a mismatch problem, the power generation efficiency of the photovoltaic solar system is remarkably reduced, and energy loss is caused.
Under complex environments, such as in the case of partial shadows, photovoltaic modules often result in a situation where the power-voltage characteristic curve of the photovoltaic array exhibits multiple power extremes. As shown in fig. 1, under normal insolation conditions, the voltage-current characteristic of the photovoltaic module is shown by the dashed line in fig. 1, the voltage-current characteristic having a maximum value, i.e. exhibiting a unipolar value curve. However, in the case of partial shading, the voltage-current characteristic curve of the photovoltaic module is shown as a solid line in fig. 1, and the voltage-current characteristic curve exhibits a stepped current waveform. Accordingly, as shown in fig. 2, under normal sunshine, the power-voltage characteristic curve of the photovoltaic module is shown by a dotted line in fig. 2, the power-voltage characteristic curve has a maximum value, i.e. presents a unipolar value curve, and the extreme value is a point a in fig. 2, i.e. the maximum point of the output power of the photovoltaic module. However, in the case of a partial shadow, the shielded partial module in the photovoltaic module changes from a power supply to a load, and current flows through the parallel bypass diode to protect the module, and since the voltage-current characteristic curve of the module shows a step current waveform, the power-voltage characteristic curve shows a plurality of power extreme points, as shown by a solid line in fig. 2.
Therefore, when the environment suddenly changes, the extreme Point changes from a single peak Point a to a changed Point B, and if a traditional Maximum Power Point Tracking (MPPT) algorithm is adopted, the photovoltaic module will eventually stably operate at a local peak Point C. Overall view, the maximum power point is the point D under the condition of local shadow, and the existing algorithm always stably operates at the point C, resulting in power loss of the photovoltaic solar system.
Therefore, the traditional direct MPPT control method based on sampling data is prone to failure due to the fact that the traditional direct MPPT control method is trapped in a local extreme point, the photovoltaic array works in a bad state actually, power is seriously mismatched, energy is lost, and a photovoltaic module is prone to damage. For this reason, some scholars propose to make the photovoltaic array perform global maximum power point tracking under the condition of local shadow and ensure global asymptotic stability by methods such as real-time data measurement, special circuit configuration or lengthy calculation. The methods can improve the output power of the photovoltaic array under the condition of local shadow, but additional circuit configuration needs to be added or corresponding calculation is tedious, so that the production cost of the photovoltaic solar system is increased, or the calculation amount is huge, and the requirement on a processor is high.
Disclosure of Invention
The first purpose of the invention is to provide a photovoltaic solar energy system control method capable of calculating the maximum power point under the condition of local shadow with high efficiency and low cost.
The second purpose of the invention is to provide a photovoltaic solar system applying the above photovoltaic solar system control method.
A third object of the present invention is to provide a computer-readable storage medium for implementing the above-mentioned photovoltaic solar system control method.
In order to achieve the first purpose of the invention, the photovoltaic solar system control method provided by the invention comprises the steps of obtaining the output power and the sampling current of the current sampling period and the last sampling period, and judging whether the working environment is a multi-power extreme environment or not according to the output power and the sampling current of the current sampling period and the last sampling period; if the current working environment is determined to be a multi-power extreme environment, changing the duty ratio of the pulse modulation signal by a preset first step length, calculating the corresponding output power under each duty ratio, searching the target duty ratio of the pulse modulation signal corresponding to the maximum output power, and adjusting the duty ratio of the pulse modulation signal output by the direct-current converter to the target duty ratio.
According to the scheme, whether the working environment is a multi-power extreme environment or not is judged through simple calculation, namely whether the working environment is in a local shadow or not, and if the working environment is in the local shadow, the target duty ratio of the pulse modulation signal corresponding to the maximum output power is found through a simple algorithm, so that the duty ratio of the pulse modulation signal output by the direct current converter is rapidly adjusted to the target duty ratio.
The photovoltaic solar system is controlled in a software mode, an additional circuit is not needed, the production cost of the photovoltaic solar system can be reduced, global scanning is carried out in a mode of gradually adjusting the duty ratio of the pulse modulation signal, the calculated amount of searching the maximum power point is not large, and the maximum power point of the photovoltaic solar system can be efficiently searched.
Preferably, the varying the duty ratio of the pulse modulation signal by the preset first step length includes: the duty cycle of the pulse modulated signal is varied by a first step size starting from a preset starting duty cycle.
Therefore, scanning is carried out from a preset initial duty ratio instead of scanning the whole duty ratio range, the calculated amount of scanning and calculation can be reduced, and the efficiency of searching the maximum power point of the photovoltaic solar system is improved.
Further, the starting duty ratio is 1-0.85 × Uoc/Uo, wherein Uoc is an open circuit voltage, and Uo is an output voltage.
When the maximum power point voltage exceeds the open circuit voltage Uoc × 085 times, the situation that the output power is a multi-extreme value does not exist, so that the situation that the searched maximum power point is wrong can be avoided by setting a reasonable initial duty ratio.
Further, the step of determining whether the working environment is the multi-power extreme environment according to the output power and the sampling current of the current sampling period and the last sampling period comprises: calculating a first ratio of the output power of the current sampling period to the output power of the previous sampling period, calculating a second ratio of the sampling current of the current sampling period to the sampling current of the previous sampling period, and determining whether the working environment is a multi-power extreme environment according to a difference value of the first ratio and the second ratio.
Therefore, whether the current working environment is a multi-power extreme value environment or not is determined through simple calculation, and the control efficiency of the photovoltaic solar system can be improved.
More preferably, if the difference between the first ratio and the second ratio is greater than a preset difference, the current working environment is determined to be a multi-power extreme environment.
Preferably, if the current working environment is determined to be a single power extreme environment, the duty ratio of the pulse modulation signal output by the dc-to-dc converter is adjusted by using a fixed voltage method or a disturbance observation method according to the input voltage determination.
Therefore, different control methods are flexibly selected according to the condition of the input voltage to adjust the duty ratio of the pulse modulation signal output by the DC converter, and the control requirement of the photovoltaic solar system is met.
If the input voltage exceeds a preset voltage range, the duty ratio of a pulse modulation signal output by the DC converter is adjusted by applying a fixed voltage method; and if the input voltage is within the preset voltage range, adjusting the duty ratio of the pulse modulation signal output by the DC converter by applying a disturbance observation method.
In a further aspect, the adjusting the duty ratio of the pulse modulation signal output by the dc-dc converter by applying the fixed voltage method includes: and setting the input reference voltage as a voltage corresponding to the maximum output power, calculating a second step length of duty ratio adjustment of the pulse modulation signal, and adjusting the duty ratio of the pulse modulation signal by the second step length.
Therefore, the input reference voltage is set to be the voltage corresponding to the maximum output power, and the duty ratio of the pulse modulation signal is gradually adjusted, so that the input voltage gradually approaches to the voltage corresponding to the maximum output power, and the photovoltaic solar system works at the maximum power point.
In a further aspect, the adjusting the duty ratio of the pulse modulation signal output by the dc-dc converter by applying the perturbation observation method includes: and adjusting the duty ratio of the pulse modulation signal output by the direct current converter according to the difference value of the output power of the current sampling period and the output power of the previous sampling period and the difference value of the input voltage of the current sampling period and the input voltage of the previous sampling period.
Therefore, the duty ratio of the pulse modulation signal can be simply calculated according to the output power and the sampling current of a plurality of current sampling periods and the last sampling period, and the adjustment efficiency of the pulse modulation signal is improved.
In a further aspect, the adjusting the duty ratio of the pulse modulation signal output by the dc-dc converter by applying the perturbation observation method includes: and adjusting the duty ratio of the pulse modulation signal output by the direct current converter by a third step length.
Therefore, the duty ratio of the pulse modulation signal is gradually adjusted through the set step length, and sudden change of the input voltage can be avoided, so that the working stability of the photovoltaic solar system is ensured.
In order to achieve the second object, the present invention provides a photovoltaic solar system, which includes a controller and a dc converter, wherein the controller includes a processor and a memory, the memory stores a computer program, and the computer program implements the steps of the control method of the photovoltaic solar system when executed by the processor.
To achieve the third objective, the present invention provides a computer-readable storage medium having a computer program stored thereon, where the computer program is executed by a processor to implement the steps of the above-mentioned photovoltaic solar system control method.
Drawings
Fig. 1 is a graph of the current-voltage characteristic of a photovoltaic solar system under normal sunlight and partial shadow conditions.
Fig. 2 is a graph of the power-voltage characteristics of a photovoltaic solar system under normal sunlight and partial shadow conditions.
Fig. 3 is a first portion of a flow chart of an embodiment of a photovoltaic solar system control method of the present invention.
Fig. 4 is a second portion of a flow chart of an embodiment of a photovoltaic solar system control method of the present invention.
Fig. 5 is a block flow diagram of calculating a second step size of the regulation duty ratio in the embodiment of the photovoltaic solar system control method of the present invention.
The invention is further explained with reference to the drawings and the embodiments.
Detailed Description
The photovoltaic solar system control method is applied to a photovoltaic solar system, preferably, the photovoltaic solar system is provided with a controller, a photovoltaic module and a direct current converter, the controller can output signals to the direct current converter so as to adjust the duty ratio of pulse modulation signals output by the direct current converter, and therefore input voltage loaded to the photovoltaic module is changed, the photovoltaic module works at the maximum power point, and therefore energy conversion efficiency of the photovoltaic solar system is improved. Preferably, a processor and a memory are arranged in the controller, the memory stores a computer program, and the processor implements the photovoltaic solar system control method by executing the computer program.
The embodiment of the control method of the photovoltaic solar system comprises the following steps:
referring to fig. 3 and 4, step S1 is first performed to collect the input power Ppv (k) of the current sampling period, the input power Ppv (k-1) of the previous sampling period, the sampling current Ipv (k) of the current sampling period, and the sampling current Ipv (k-1) of the previous sampling period, and step S2 is then performed to calculate that the current working environment is an environment with multiple power extremes according to the collected data. Generally, environmental mutation is bidirectional change, and when illumination is suddenly enhanced, local reference often does not exist, so that a power-voltage characteristic curve of a photovoltaic module does not have a multi-peak condition, and the requirement of stable operation of a photovoltaic solar system can be met by using a traditional power maximum point tracking method; when local shading or partial shadow occurs, the power-voltage characteristic curve of the photovoltaic module will show a multi-peak condition, and therefore it is necessary to determine whether the current working environment is an environment with multiple power extrema. In this embodiment, the following formula is adopted for determination:
Ppv (k)/Ppv (k-1) -Ipv (k)/Ipv (k-1) >. DELTA (equation 1)
Wherein, the delta is a preset difference value which is preset. It can be seen that, first, a first ratio of the input power Ppv (k) of the current sampling period to the input power Ppv (k-1) of the previous sampling period is calculated, and a second ratio of the sampling current Ipv (k) of the current sampling period to the sampling current Ipv (k-1) of the previous sampling period is calculated, and a difference between the first ratio and the second ratio is calculated.
In general, when the environment is not mutated, the difference between the first ratio and the second ratio is a very small value, and thus, the predetermined difference Δ in formula 1 is 0.3. If the current condition satisfies equation 1, that is, the difference between the first ratio and the second ratio is greater than 0.3, it is determined that the environment has a sudden change, and the current operating environment is a multi-power extreme environment, so that the determination result in step S2 is yes, and the operating mode of the multi-power extreme environment needs to be entered, and step S15 is executed. If the current condition does not satisfy formula 1, that is, the difference between the first ratio and the second ratio is less than or equal to 0.3, it is determined that the environment has not suddenly changed, and the current operating environment is a single power extreme environment, so the determination result of step S2 is no, and step S3 is performed. Under the environment of single power extreme value, the photovoltaic solar system can be controlled by adopting the traditional maximum power point tracking method.
Specifically, in step S3, it is determined whether the input voltage upv (k) in the current sampling period is within a predetermined range, for example, whether a condition of Um- Δ U < upv (k) < Um +/Δ U is satisfied, and thus the predetermined range is (Um- Δ U, Um +/Δ U). The method includes the steps that Um is a voltage corresponding to the maximum power output of the photovoltaic solar system, delta U is a limit voltage value of switching between a fixed voltage method and a disturbance observation method, and in the embodiment, the value of the delta U is Np multiplied by 0.2 of the number of photovoltaic modules connected in series with the photovoltaic solar system. Generally, after the structure and type of the photovoltaic module are determined, the voltage Um corresponding to the maximum power point is also determined, and may be obtained by calculating the open-circuit voltage Uoc, for example, generally, Um ≈ 0.8 × Uoc.
If the input voltage Upv (k) is within the preset range, the sampling fixed voltage method controls the photovoltaic solar system, namely the sampling fixed voltage method adjusts the duty ratio of the pulse modulation signal output by the direct current converter. Specifically, step S4 is executed first, and the input reference voltage Uref is set, for example, the input reference voltage Uref is set to the voltage Um corresponding to the maximum power output of the photovoltaic solar system, that is, Uref is set to Um. Then, step S5 is executed to calculate a second step Δ D of the duty ratio of the pulse modulated signal output by the dc converter, where the second step Δ D is a step of stabilizing the output voltage to Um by proportional-integral control (PI control) under a fixed voltage method in this embodiment.
Referring to fig. 5, the controller 11 receives an input reference voltage Uref and an input current Ipv, the voltage regulator 13 in the voltage stabilizing circuit 12 outputs a voltage signal, which is the input reference current Ipv _ ref, the signal output by the controller 11 and the input reference current Ipv _ ref are calculated to form a voltage U input to the PI controller 14, the controller 11 also outputs a voltage Up to the PI controller 14, the PI controller 14 outputs an electrical signal to the current regulator 15, the current regulator 15 generates a second step size Δ D according to the result of the PI calculation and outputs the second step size Δ D to the pulse modulation signal generating circuit 16, and the pulse modulation signal generating circuit 16 adjusts the duty ratio of the output pulse modulation signal according to the second step size Δ D. Therefore, the second step Δ D is data obtained by applying the PI operation.
After calculating the second step length Δ D, step S6 is executed to adjust the duty ratio of the pulse modulation signal output by the dc converter, specifically, the duty ratio Dref of the pulse modulation signal output by the dc converter in the previous sampling period is added to the second step length Δ D, so as to obtain the duty ratio Dref of the pulse modulation signal output by the dc converter in the current sampling period, that is, Dref (k) ═ Dref (k-1) + Δ D. In this embodiment, the second step Δ D is a vector. Therefore, in the present embodiment, the duty ratio of the pulse modulation signal output from the dc converter is adjusted by the second step Δ D under the fixed voltage method. Of course, if the state is the initial state, the duty Dref of the pulse modulation signal output by the dc converter may be a preset initial value.
The fixed voltage method can ensure that the duty ratio Dref of the pulse modulation signal output by the direct current converter is adjusted in a smaller amplitude when the input voltage fluctuates in a smaller range, so that the control requirement of the photovoltaic solar system is met, and the photovoltaic solar system can stably work at the maximum power point.
If the determination result in step S3 is no, that is, upv (k) < Um- Δ U, or upv (k) > Um +. Δ U, step S7 is executed to determine whether the output power Ppv (k) of the current sampling period is equal to the output power Ppv (k-1) of the previous sampling period, and if yes, step S14 is executed to set the current output voltage upv (k) to the voltage Um corresponding to the maximum output power, that is, Um ═ upv (k).
If the output power Ppv (k) of the current sampling period is not equal to the output power Ppv (k-1) of the previous sampling period, that is, if the determination result of step S7 is negative, step S8 is performed, it is determined whether the output power Ppv (k) of the current sampling period is greater than the output power Ppv (k-1) of the previous sampling period, if not, step S9 is performed, and if yes, step S10 is performed.
In step S9, it is determined whether the input voltage Upv (k) in the current sampling period is greater than the input voltage Upv (k-1) in the previous sampling period, if yes, step S11 is executed to reduce the duty ratio of the pulse modulation signal, specifically, a third step length Δ d2 of the duty ratio adjustment of the pulse modulation signal is set, and a disturbance step length of the duty ratio of the third step length Δ d2 is set, where an embodiment takes a value of 0.01. Certainly, in actual application, the value of the third step length Δ d2 may be adjusted according to actual needs, and the value may be greater than or less than 0.01. When the duty cycle of the pulse modulated signal is decreased, the magnitude of each decrease is the third step Δ d2, i.e. a new duty cycle is obtained after subtracting the third step Δ d2 from the current duty cycle.
If the determination result in the step S9 is "no", then step S12 is executed to increase the duty ratio of the pulse modulation signal, in this embodiment, the amplitude of each increase is the third step Δ d2, that is, after the third step Δ d2 is added to the current duty ratio, a new duty ratio is obtained.
If the result of the determination in the step S8 is yes, step S10 is executed to determine whether the input voltage Upv (k) in the current sampling period is smaller than the input voltage Upv (k-1) in the previous sampling period, if so, step S12 is executed to increase the duty ratio of the pulse modulation signal, otherwise, step S13 is executed to decrease the duty ratio of the pulse modulation signal, and the execution method in the step S13 is the same as that in the step S11, and is not repeated.
After step S11, step S12, or step S13 is executed, step S14 is executed to set the input voltage upv (k) of the current sampling period to the voltage Um corresponding to the maximum output power, and step S17 is executed to update the input voltage, the input current, and the output power of the current sampling period, and the process proceeds to the next cycle. Since the data of the current sampling period will become the data of the "previous sampling period" in the next sampling period, the data of the current sampling period needs to be updated to the data of the "previous sampling period", that is, the value of Upv (k) is assigned to Upv (k-1), the value of Ipv (k) is assigned to Ipv (k-1), and the value of Ppv (k) is assigned to Ppv (k-1).
If the judgment result in the step S2 is yes, indicating that the current working environment is a multi-power extremum environment, then the duty ratio of the pulse modulation signal corresponding to the maximum output power is found out by using a global scan duty ratio algorithm. First, step S15 is executed to set a start duty ratio and a first step Δ d1 of duty ratio adjustment of a pulse modulation signal output from the dc converter, and to calculate output power. In this embodiment, the whole voltage range is not scanned, and according to the characteristics of the photovoltaic solar system, when the voltage corresponding to the maximum power exceeds 085 times of the open-circuit voltage Uoc, there is no multi-peak condition, that is, the power-voltage characteristic curve does not have a plurality of extreme values, so that, when performing global scanning, scanning is started from a set initial duty ratio, the calculated amount of scanning can be reduced, and thus the calculated amount of searching the duty ratio of the pulse modulation signal corresponding to the maximum power is increased. For example, the initial duty ratio set in this embodiment is 1-0.85 × Uoc/Uo, where Uoc is the open circuit voltage and Uo is the output voltage.
The first step length Δ d1 of duty ratio adjustment of the pulse modulation signal output by the dc converter can be flexibly adjusted, and in this embodiment, the value of the first step length Δ d1 is the same as the value of the third step length Δ d2, and both values are 0.01. Certainly, in practical application, the value of the first step length Δ d1 and the value of the third step length Δ d2 may be different. After determining the duty ratio of the pulse modulation signal output by the dc converter, the output power Ppv at the duty ratio is calculated, for example, the output voltage and the output current at the duty ratio of the pulse modulation signal are calculated, and the output power is calculated according to the output voltage and the output current.
The duty cycle is then adjusted in units of the first step Δ d1, for example, by increasing or decreasing a first step Δ d1 based on the previous duty cycle, and the corresponding output power at the new duty cycle is calculated until the maximum or minimum of the duty cycle is reached.
Next, step S16 is executed to find the maximum value of the output power, determine the duty ratio of the pulse modulation signal corresponding to the maximum output power, and adjust the duty ratio of the pulse modulation signal output by the dc converter to the target duty ratio with the duty ratio as the target duty ratio, so that the output power of the photovoltaic solar system can be stabilized at the maximum value, thereby avoiding the conversion efficiency from being too low due to too small output power of the photovoltaic solar system. Finally, step S17 is executed to update the input voltage, the input current, and the output power of the current sampling period.
Because the photovoltaic solar system is controlled in a software mode, the photovoltaic solar system can stably operate in the state of the maximum output power, and a hardware circuit does not need to be adjusted, so that the production cost of the photovoltaic solar system can be reduced. In addition, the algorithm of the embodiment is simple, the use of tedious calculation is avoided, only global scanning is performed in the process of searching the maximum power point, the calculation amount is small, and the efficiency of adjusting the duty ratio can be improved.
Photovoltaic solar energy system embodiment:
the photovoltaic solar system of the embodiment is provided with a controller, a photovoltaic module and a direct current converter, wherein the controller outputs a signal to the direct current converter so as to change the duty ratio of a pulse modulation signal output by the direct current converter. The controller of the photovoltaic solar system comprises a processor, a memory and a computer program stored in the memory and capable of running on the processor, and the processor executes the computer program to realize the steps of the photovoltaic solar system control method.
For example, a computer program may be partitioned into one or more modules that are stored in a memory and executed by a processor to implement the modules of the present invention. One or more of the modules may be a series of computer program instruction segments capable of performing certain functions, which are used to describe the execution of the computer program in the terminal device.
The Processor may be a Central Processing Unit (CPU), or may be other general-purpose Processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), an off-the-shelf Programmable Gate Array (FPGA) or other Programmable logic device, a discrete Gate or transistor logic device, a discrete hardware component, or the like. The general-purpose processor may be a microprocessor or the processor may be any conventional processor or the like, the processor being the control center of the terminal device and connecting the various parts of the entire terminal device using various interfaces and lines.
The memory may be used to store computer programs and/or modules, and the processor may implement various functions of the terminal device by running or executing the computer programs and/or modules stored in the memory and invoking data stored in the memory. The memory may mainly include a storage program area and a storage data area, wherein the storage program area may store an operating system, an application program required for at least one function, and the like; the storage data area may store data created according to the use of the mobile phone, and the like. In addition, the memory may include high speed random access memory, and may also include non-volatile memory, such as a hard disk, a memory, a plug-in hard disk, a Smart Media Card (SMC), a Secure Digital (SD) Card, a Flash memory Card (Flash Card), at least one magnetic disk storage device, a Flash memory device, or other volatile solid state storage device.
Computer-readable storage medium embodiments:
the computer program stored in the photovoltaic solar system may be stored in a computer-readable storage medium if it is implemented in the form of a software functional unit and sold or used as a separate product. Based on such understanding, all or part of the flow in the method of the embodiment described above can be realized by the present invention, and the method can also be implemented by a computer program to instruct related hardware, where the computer program can be stored in a computer readable storage medium, and when the computer program is executed by a processor, the steps of the method for controlling a photovoltaic solar system described above can be realized.
Wherein the computer program comprises computer program code, which may be in the form of source code, object code, an executable file or some intermediate form, etc. The computer readable medium may include: any entity or device capable of carrying computer program code, recording medium, U.S. disk, removable hard disk, magnetic disk, optical disk, computer Memory, Read-Only Memory (ROM), Random Access Memory (RAM), electrical carrier wave signals, telecommunications signals, software distribution media, and the like. It should be noted that the computer readable medium may contain other components which may be suitably increased or decreased as required by legislation and patent practice in jurisdictions, for example, in some jurisdictions, in accordance with legislation and patent practice, the computer readable medium does not include electrical carrier signals and telecommunications signals.
Finally, it is emphasized that the present invention is not limited to the above-described embodiments, such as the variation of the first step size, the second step size, the third step size, or the variation of the specific control method of the fixed voltage method, and such variations should also be included in the protection scope of the present claims.
Claims (10)
1. A photovoltaic solar energy system control method, comprising:
Acquiring the output power and the sampling current of the current sampling period and the last sampling period, and judging whether the working environment is a multi-power extreme value environment according to the output power and the sampling current of the current sampling period and the last sampling period: calculating a first ratio of output power of a current sampling period to output power of a previous sampling period, calculating a second ratio of sampling current of the current sampling period to sampling current of the previous sampling period, and if the difference value between the first ratio and the second ratio is greater than a preset difference value, determining that the current working environment is a multi-power extreme environment;
if the current working environment is determined to be a multi-power extreme environment, changing the duty ratio of the pulse modulation signal by a preset first step length, calculating the corresponding output power under each duty ratio, searching the target duty ratio of the pulse modulation signal corresponding to the maximum output power, and adjusting the duty ratio of the pulse modulation signal output by the direct-current converter to the target duty ratio.
2. The photovoltaic solar system control method of claim 1, wherein:
varying the duty cycle of the pulse modulated signal at a preset first step size comprises: and starting from a preset starting duty ratio, changing the duty ratio of the pulse modulation signal by the first step length.
3. The photovoltaic solar system control method of claim 2, wherein:
the initial duty ratio is 1-0.85 XUoc/UO, wherein Uoc is open-circuit voltage, and UO is output voltage.
4. The photovoltaic solar system control method according to any one of claims 1 to 3, characterized in that:
and if the current working environment is confirmed to be a single-power extreme environment, the duty ratio of the pulse modulation signal output by the direct-current converter is adjusted by confirming and applying a fixed voltage method or a disturbance observation method according to the input voltage.
5. The photovoltaic solar system control method of claim 4, wherein:
if the input voltage is within a preset voltage range, adjusting the duty ratio of a pulse modulation signal output by the direct current converter by using a fixed voltage method;
and if the input voltage exceeds the preset voltage range, adjusting the duty ratio of the pulse modulation signal output by the direct current converter by using a disturbance observation method.
6. The photovoltaic solar system control method of claim 5, wherein:
the step of adjusting the duty ratio of the pulse modulation signal output by the direct current converter by applying a fixed voltage method comprises the following steps: and setting the input reference voltage as a voltage corresponding to the maximum output power, calculating a second step length of duty ratio adjustment of the pulse modulation signal, and adjusting the duty ratio of the pulse modulation signal by the second step length.
7. The photovoltaic solar system control method of claim 5, wherein:
the step of adjusting the duty ratio of the pulse modulation signal output by the direct current converter by applying a disturbance observation method comprises the following steps: and adjusting the duty ratio of the pulse modulation signal output by the direct current converter according to the difference value of the output power of the current sampling period and the output power of the previous sampling period and the difference value of the input voltage of the current sampling period and the input voltage of the previous sampling period.
8. The photovoltaic solar system control method of claim 7, wherein:
the step of adjusting the duty ratio of the pulse modulation signal output by the direct current converter by applying a disturbance observation method comprises the following steps: and adjusting the duty ratio of the pulse modulation signal output by the direct current converter by a third step length.
9. Photovoltaic solar system with a controller and a dc converter, characterized in that the controller comprises a processor and a memory, the memory storing a computer program which, when executed by the processor, carries out the steps of the photovoltaic solar system control method according to any one of claims 1 to 8.
10. A computer-readable storage medium having stored thereon a computer program, characterized in that: the computer program, when executed by a processor, implements the steps of the photovoltaic solar system control method of any one of claims 1 to 8.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000347753A (en) * | 1999-06-08 | 2000-12-15 | Mitsubishi Electric Corp | Solar battery controller and solar power generating device |
| CN102722212A (en) * | 2012-07-02 | 2012-10-10 | 中国矿业大学 | Maximum power point tracking method for photovoltaic power generation system under non-uniform illumination |
| CN105159387A (en) * | 2015-08-31 | 2015-12-16 | 江苏金智科技股份有限公司 | Maximum power point implementation method and device base on three-level step length |
| CN106096715A (en) * | 2016-05-05 | 2016-11-09 | 江苏方天电力技术有限公司 | Photovoltaic module shade decision method based on peak counting Yu parameter identification |
| CN108304026A (en) * | 2017-11-30 | 2018-07-20 | 深圳市首航新能源有限公司 | A kind of powerinjected method method |
| CN111665900A (en) * | 2020-05-26 | 2020-09-15 | 国网江苏省电力有限公司盐城供电分公司 | Photovoltaic array multimodal maximum power tracking method based on filling function algorithm |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5942183B2 (en) * | 2011-11-14 | 2016-06-29 | パナソニックＩｐマネジメント株式会社 | Power conditioner for photovoltaic power generation |
| CN105867514B (en) * | 2016-04-15 | 2017-09-01 | 浙江大学 | A kind of photovoltaic system multi-peak maximum power tracking method and system |
-
2021
- 2021-01-19 CN CN202110069008.3A patent/CN112904929B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000347753A (en) * | 1999-06-08 | 2000-12-15 | Mitsubishi Electric Corp | Solar battery controller and solar power generating device |
| CN102722212A (en) * | 2012-07-02 | 2012-10-10 | 中国矿业大学 | Maximum power point tracking method for photovoltaic power generation system under non-uniform illumination |
| CN105159387A (en) * | 2015-08-31 | 2015-12-16 | 江苏金智科技股份有限公司 | Maximum power point implementation method and device base on three-level step length |
| CN106096715A (en) * | 2016-05-05 | 2016-11-09 | 江苏方天电力技术有限公司 | Photovoltaic module shade decision method based on peak counting Yu parameter identification |
| CN108304026A (en) * | 2017-11-30 | 2018-07-20 | 深圳市首航新能源有限公司 | A kind of powerinjected method method |
| CN111665900A (en) * | 2020-05-26 | 2020-09-15 | 国网江苏省电力有限公司盐城供电分公司 | Photovoltaic array multimodal maximum power tracking method based on filling function algorithm |
Non-Patent Citations (1)
| Title |
|---|
| 基于峰值计数与参数辨识的光伏组件阴影判定方法;陈凌 等;《电力系统保护与控制》;20161201;第44卷(第23期);第125-132页 * |
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