A double-sided photovoltaic tracking control method and universal controller

Abstract

The present invention discloses a double-sided photovoltaic tracking control method and a universal controller, which determines the tracking angle target value λ, adjusts the tracking bracket azimuth angle β to be consistent with the tracking angle target value λ; when the rotation angle of the tracking bracket reaches the power optimization interval angle γ, the tracking bracket is driven to rotate and the tracking bracket azimuth angle β' at the maximum power collection within the rotation range is determined, and β'=λ+ε at this time; the tracking angle target value λ is re-determined with ε as the correction value; the present invention also discloses a double-sided photovoltaic tracking universal controller, which is coupled by a commonly used GPS module, a tilt sensor module, a motor control module and a communication module, and has good adaptability to different types of inverters and motor-driven tracking brackets. The above technical solution can realize the optimization of the output power of the component, can more accurately obtain the optimal power output position of the double-sided photovoltaic component, improve the power generation of the component, and is suitable for the tracking operation of the double-sided photovoltaic component.

Description

Technical Field

[0001] The invention relates to a double-sided photovoltaic tracking control method and a universal controller, belonging to the technical field of photovoltaic power station control. Background Art

[0002] Bifacial photovoltaic cells are a new type of cells that can generate electricity on both sides. The power generation efficiency of photovoltaic modules made with bifacial photovoltaic cells can be improved to a certain extent, and they have higher power generation than single-sided photovoltaic modules. When sunlight shines on bifacial modules, some of the light will be reflected by the surrounding environment to the back of the bifacial modules. This part of light can be absorbed by the cells, thus contributing to the photocurrent and efficiency of the cells. In order to further increase the power generation of bifacial photovoltaic modules and reduce the price of photovoltaic electricity, flat single-axis tracking technology is added when bifacial photovoltaic modules are running. The tracking system in the solar photovoltaic power generation system is used to track the sun according to the trajectory of the sun, and adjust the angle of the tracking bracket in real time so that the solar photovoltaic power generation module installed on the tracking bracket can always face the direction of sunlight, thereby increasing the amount of solar radiation received by the photovoltaic power generation module and increasing the power generation of the solar photovoltaic power generation system. Compared with ordinary photovoltaic modules, the back of bifacial photovoltaic modules also generates electricity, and the traditional tracking algorithm does not consider the power generation gain of the back, so it is necessary to optimize the traditional tracking algorithm to obtain the maximum radiation and increase the power generation. Summary of the invention

[0003] Therefore, an object of the present invention is to provide a double-sided photovoltaic tracking control method and a universal controller, which can improve the power generation of the components by obtaining the optimal power output position of the double-sided photovoltaic components.

[0004] In order to achieve the above object, a double-sided photovoltaic tracking control method of the present invention comprises the following steps:

[0005] (1) Determine the target tracking angle value λ, and adjust the tracking bracket azimuth angle β to be consistent with the target tracking angle value λ;

[0006] (2) When the cumulative rotation angle of the tracking bracket reaches the power optimization interval angle γ, the tracking bracket is driven to rotate and the tracking bracket azimuth angle β' at which the maximum power is collected within the rotation range is determined. At this time, β'=λ+ε;

[0007] (3) Re-determine the tracking angle target value λ using ε as the correction value and repeat step 1.

[0008] At the initialization of the system, the real-time solar azimuth angle α is used as the tracking angle target value λ.

[0009] In step 2, the rotation range of the driving tracking bracket is: firstly, the bracket is rotated forward by a symmetrical rotation angle δ, and then rotated backward by an angle 2δ.

[0010] In step 1, when the tracking bracket azimuth angle β differs from the tracking angle target value λ by an angle of n, the tracking bracket is driven to rotate until the tracking bracket azimuth angle β is equal to the tracking angle target value λ.

[0011] The present invention also provides a double-sided photovoltaic tracking universal controller, comprising a GPS module, a tilt sensor module, a motor control module, a CPU module and a communication module; the GPS module, the tilt sensor module and the communication module are all connected to the CPU module; the CPU module is connected to the motor control module;

[0012] GPS module, used to obtain real-time solar azimuth angle α information and transmit it to the CPU module;

[0013] The tilt sensor module is used to obtain the azimuth angle β information of the tracking bracket in real time and transmit it to the CPU module;

[0014] A motor control module, used for driving a DC motor according to instructions from a CPU module;

[0015] A communication module, used for at least reading power data of the inverter and transmitting it to the CPU module;

[0016] The CPU module is used to process the acquired angle data and power data and output them to control the motor control module;

[0017] During the initial operation of the photovoltaic module, the CPU module is used to read the solar azimuth angle α data output by the GPS module and use it as the tracking angle target value λ; when the cumulative rotation angle of the tracking bracket reaches the power optimization interval angle γ, the motor control module drives the DC motor to drive the tracking bracket to rotate forward and backward. During this rotation process, the CPU module reads the tracking bracket azimuth angle β data output by the tilt sensor module and the inverter power data output by the communication module, determines the tracking bracket azimuth angle β' when the maximum power is collected within the rotation range, and obtains the tracking angle correction value ε. At this time, β'=λ+ε. During the next tracking, the CPU module will use ε as the correction value to re-determine the tracking angle target value λ.

[0018] The tracking bracket controller is also used to control the motor to drive the tracking bracket to first rotate forward through a bracket symmetrical rotation angle δ, and then rotate backward through an angle 2δ, so as to determine the rotation range.

[0019] The communication module reads the data of the inverter through RS485 communication mode or PLC communication mode.

[0020] The communication mode of the tilt sensor module is RS485 communication.

[0021] By adopting the above technical scheme, the bifacial photovoltaic tracking control method and universal controller of the present invention can at least read the power data of the inverter through the controller, and can directly drive the motor to realize the rotation of the tracking bracket. The tracking bracket controller reads the rotation angle of the tracking bracket in real time, thereby realizing closed-loop control of the tracking bracket. When the flat single-axis tracking bifacial photovoltaic module is running, the tracking bracket controller drives the tracking bracket to rotate symmetrically through the motor to realize the optimization of the module output power, and repeat the above steps every specific angle. The tracking strategy of the present invention can more accurately obtain the optimal power output position of the bifacial photovoltaic module, improve the power generation of the module, and is suitable for the tracking operation of the bifacial photovoltaic module. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a flowchart of the double-sided photovoltaic tracking control method of the present invention.

[0023] Figure 2 Schematic diagram of a universal controller of the present invention. DETAILED DESCRIPTION

[0024] The present invention is further described in detail below through the accompanying drawings and specific embodiments.

[0025] like Figure 1 As shown, a double-sided photovoltaic tracking control method of the present invention comprises Figure 2 The tracking bracket controller shown is realized by coupling a GPS module 21, a tilt sensor module 22, a communication module 23, a CPU module 24 and a motor control module 25, and has good versatility. The controller can read the current, voltage and power data of the inverter through the communication module 23 using RS485 communication mode or PLC communication mode.

[0026] The tracking support controller can directly drive the DC motor through the motor control module 25 to achieve the tracking rotation of the support. The tracking support controller tilt sensor module 22 reads the rotation angle of the tracking support in real time through RS485 communication mode, thereby achieving closed-loop control of the tracking support.

[0027] GPS module, used to obtain real-time solar azimuth angle α information and transmit it to the CPU module;

[0028] The tilt sensor module is used to obtain the azimuth angle β information of the tracking bracket in real time and transmit it to the CPU module;

[0029] A motor control module, used for driving a DC motor according to instructions from a CPU module;

[0030] A communication module, used for at least reading power data of the inverter and transmitting it to the CPU module;

[0031] The CPU module is used to process the acquired angle data and power data and output them to control the motor control module;

[0032] During the initial operation of the photovoltaic module, the CPU module is used to read the solar azimuth angle α data output by the GPS module and use it as the tracking angle target value λ; when the cumulative rotation angle of the tracking bracket reaches the power optimization interval angle γ, the motor control module drives the DC motor to drive the tracking bracket to rotate forward and backward. During this rotation process, the CPU module reads the tracking bracket azimuth angle β data output by the tilt sensor module and the inverter power data output by the communication module, determines the tracking bracket azimuth angle β' when the maximum power is collected within the rotation range, and obtains the tracking angle correction value ε. At this time, β'=λ+ε. During the next tracking, the CPU module will use ε as the correction value to re-determine the tracking angle target value λ.

[0033] When the flat single-axis tracking bifacial photovoltaic module is running, the tracking bracket controller drives the tracking bracket to rotate symmetrically through the DC motor to optimize the output power of the module, and repeats the above steps at every specific angle. The specific method includes the following steps:

[0034] (1) For the conventional tracking operation mode, the tracking bracket controller can calculate the solar azimuth angle α in real time and obtain the tracking bracket azimuth angle β through RS485 communication;

[0035] (2) The control parameters of the tracking bracket controller also include the tracking angle target value λ;

[0036] (3) The tracking angle target value λ is equal to the solar azimuth angle α in the initialization state and changes simultaneously with α. When the tracking bracket azimuth angle β differs from the tracking angle target value λ by an angle n, the PV module starts tracking and the tracking bracket azimuth angle β begins to change until it is equal to the tracking angle target value λ.

[0037] (4) For the power optimization operation mode, the support symmetry rotation angle δ and the power optimization interval angle γ are set on the tracking support controller before starting;

[0038] (5) When starting the power optimization operation, the tracking bracket will first rotate forward by an angle δ, and then rotate backward by an angle 2δ with the initial position before rotation as the symmetry axis;

[0039] (6) During the rotation of the tracking bracket, the inverter feeds back the power data to the tracking bracket controller in real time through the data acquisition system;

[0040] (7) The controller processes and analyzes the power data to obtain the tracking bracket azimuth angle β' corresponding to the maximum power. At this time, β'=λ+ε, where ε is the tracking target angle correction value. At this time, the bracket rotates to β';

[0041] (8) The support continues to perform conventional tracking operation, which is different from step 3 in that the target tracking angle is equal to λ+ε;

[0042] (9) When the cumulative rotation angle of the bracket reaches angle γ, the conventional tracking operation ends and the next power optimization operation begins, repeating steps 5 to 9.

[0043] Obviously, the above embodiments are only examples for clear explanation, and are not intended to limit the implementation methods. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from them are still within the protection scope of the invention.

Claims

1. A double-sided photovoltaic tracking control method, characterized in that: The following steps are involved: (1) Determine the target tracking angle value λ, and adjust the tracking bracket azimuth angle β to be consistent with the target tracking angle value λ; (2) When the cumulative rotation angle of the tracking bracket reaches the power optimization interval angle γ, the tracking bracket is driven to rotate and the tracking bracket azimuth angle β' at which the maximum power is collected within the rotation range is determined. At this time, β'=λ+ε; (3) Re-determine the tracking angle target value λ using ε as the correction value, and repeat step 1; In step 2, the rotation range of the driving tracking bracket is: firstly, the bracket is rotated forward by a symmetrical rotation angle δ, and then rotated backward by an angle 2δ; In step 1, when the tracking bracket azimuth angle β differs from the tracking angle target value λ by an angle of n, the tracking bracket is driven to rotate until the tracking bracket azimuth angle β is equal to the tracking angle target value λ; The double-sided photovoltaic tracking control method is implemented by a double-sided photovoltaic tracking universal controller, which includes a GPS module, a tilt sensor module, a motor control module, a CPU module and a communication module; the GPS module, the tilt sensor module and the communication module are all connected to the CPU module; the CPU module is connected to the motor control module; GPS module, used to obtain real-time solar azimuth angle α information and transmit it to the CPU module; The tilt sensor module is used to obtain the azimuth angle β information of the tracking bracket in real time and transmit it to the CPU module; A motor control module, used for driving a DC motor according to instructions from a CPU module; A communication module, used for at least reading power data of the inverter and transmitting it to the CPU module; The CPU module is used to process the acquired angle data and power data and output them to control the motor control module; During the initial operation of the photovoltaic module, the CPU module is used to read the solar azimuth angle α data output by the GPS module and use it as the tracking angle target value λ; when the cumulative rotation angle of the tracking bracket reaches the power optimization interval angle γ, the motor control module drives the DC motor to drive the tracking bracket to rotate forward and backward. During this rotation process, the CPU module reads the tracking bracket azimuth angle β data output by the tilt sensor module and the inverter power data output by the communication module, determines the tracking bracket azimuth angle β' when the maximum power is collected within the rotation range, and obtains the tracking angle correction value ε. At this time, β'=λ+ε. During the next tracking, the CPU module will use ε as the correction value to re-determine the tracking angle target value λ.

2. A double-sided photovoltaic tracking control method as claimed in claim 1, characterized in that: The communication module reads the data of the inverter through RS485 communication mode or PLC communication mode.

3. A double-sided photovoltaic tracking control method as claimed in claim 1, characterized in that: The communication mode of the tilt sensor module is RS485 communication.

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