A solar photovoltaic inverter and photovoltaic control system

Abstract

The invention relates to the technical field of photovoltaic power supply, and discloses a solar photovoltaic inverter and a photovoltaic control system, wherein the photovoltaic inverter comprises: an inverter body, wherein the input end of the inverter body is connected to a power supply module through a power supply switching module, and the output end of the inverter body is connected to an electrical device to provide the electrical device with the power required for operation; the inverter body is composed of a frequency conversion control module, an MPPT controller, and a protection module, and the frequency conversion control module is electrically connected to the MPPT controller and the protection module; the frequency conversion control module is used for converting electric energy, converting direct current power into alternating current power, and obtaining a three-phase alternating current output by turning on and off a switching device; the MPPT controller is used for providing a control signal to the frequency conversion control module to adjust the power supply voltage and frequency of the electrical device, and the protection module monitors the voltage and current in the circuit and takes effect in an abnormal situation; the above-mentioned inverter is applied in the photovoltaic control system.

Description

Technical Field

[0001] The present invention relates to the technical field of photovoltaic power supply, and more specifically, to a solar photovoltaic inverter and a photovoltaic control system. Background Art

[0002] With the massive increase in the consumption of conventional energy such as oil and coal, the deteriorating ecological environment has forced countries around the world to actively seek a new sustainable energy path. Clean energy such as solar energy, wind energy, and geothermal energy has gradually attracted human attention, and among them, solar energy is undoubtedly in the most prominent position. Therefore, in many remote areas with sufficient light energy, the use of light energy has great social and economic benefits, and making full use of solar energy resources has great application prospects. At present, ordinary inverters are used to directly connect photovoltaic cells to drive and control the load of electrical equipment. However, due to the different load equipment, the power demand in actual application is also different, and the inverter is difficult to meet the use requirements. Summary of the invention

[0003] In order to overcome the deficiencies of the prior art, the present invention provides a solar photovoltaic inverter and a photovoltaic control system, which have the advantage of more precise operation.

[0004] To achieve the above object, the present invention provides the following technical solution: a solar photovoltaic inverter, comprising: an inverter body, the input end of the inverter body is connected to the power supply module through a power supply switching unit, and the output end of the inverter body is connected to the power-consuming device to provide the power required for the power-consuming device to work;

[0005] The inverter body is composed of a frequency conversion control module, an MPPT controller, and a protection module, and the frequency conversion control module is connected to the MPPT controller and the protection module; the inverter body is connected to a temperature adjustment module;

[0006] The inverter body is used for converting electric energy, converting DC power into AC power, and obtaining three-phase AC output by turning on and off the switching device;

[0007] The MPPT controller is used to provide a control signal to the inverter body to adjust the power supply voltage and frequency of the electrical equipment;

[0008] The protection module monitors the voltage and current in the circuit and takes effect in abnormal situations;

[0009] The protection module includes an overvoltage protection unit and an overcurrent protection unit. The overvoltage protection unit monitors the output voltage of the inverter body through the voltage monitoring unit and automatically disconnects when the voltage is judged to be abnormal; the overcurrent protection unit monitors the output current of the inverter body through the current monitoring unit and automatically disconnects when the current is judged to be abnormal;

[0010] The temperature regulating module is provided with a temperature sensor group and a heat dissipation fan group, wherein the temperature sensor group includes a plurality of groups of temperature sensors, and the heat dissipation fan group includes a plurality of groups of fans;

[0011] The inverter body is divided into three groups of areas from the inside to the outside according to the heating area, which are respectively recorded as the primary heating area, the secondary heating area, and the tertiary heating area; a temperature sensor is set in each heating area, and the temperature value of the corresponding area is taken, which is recorded as the primary area temperature value Q1, the secondary area temperature value Q2, and the tertiary area temperature value Q3;

[0012] The overheat risk coefficient G of the inverter body is obtained according to the temperature value Q1 of the first zone, the temperature value Q2 of the second zone, and the temperature value Q3 of the third zone. r ; The overheating risk factor G r The calculation formula is as follows:

[0013]

[0014] In the formula, α, β, and γ are the weight coefficients of the first-level heating area, the second-level heating area, and the third-level heating area on the overall temperature, which are set by the staff, where α>β>γ; Q x , Q Y , Q Z They are the temperature values ​​of the first-level heating area, the second-level heating area, and the third-level heating area when they are working normally, which are obtained by detection; h, i, and j are the balancing values ​​of the first-level heating area, the second-level heating area, and the third-level heating area, which are the temperature value Q1 of the first area, the temperature value Q2 of the second area, and the temperature value Q3 of the third area, which are set by the staff;

[0015] The overheating risk factor G r The preset inverter overheat threshold G y For comparison, when G r >G y When the temperature is low, the cooling fan in the cooling fan unit is started to cool down.

[0016] As a preferred technical solution of the present invention, the frequency conversion control module is composed of a rectifier, an inverter, a smoothing rectifier and a filter, and the four are connected in sequence;

[0017] Wherein, the rectifier is connected to the power supply switching unit to convert the current output by the power supply switching unit into direct current;

[0018] The inverter converts the DC power rectified by the rectifier into AC power that meets the frequency of the electrical equipment;

[0019] The smoothing rectifier is used to smooth the voltage output by the rectifier;

[0020] The filter is used to eliminate harmonics in the power line;

[0021] The inverter body is also provided with a function auxiliary module, which includes a communication unit and a signal conversion unit. The communication unit is connected to the management terminal via a wireless signal; the signal conversion unit converts the AC and DC voltages and currents in the inverter body into digital quantities for display.

[0022] As a preferred technical solution of the present invention, the MPPT controller controls the inverter body to always output at maximum power under any sunlight conditions and temperature conditions, and the MPPT controller is provided with a speed regulation unit; the speed regulation unit completes the speed control of the electrical equipment according to the frequency output of the MPPT controller.

[0023] As a preferred technical solution of the present invention, the inverter body also includes an idling protection module, which is composed of a detection sensor, a signal processing circuit, and a control execution unit, wherein the detection sensor is used to detect the working environment of the electrical equipment, the signal processing circuit receives the signal of the detection sensor and determines whether the environment meets the working conditions of the electrical equipment, and the control execution unit takes action according to the analysis result of the signal processing circuit, and reduces the operating power of the electrical equipment or shuts down when the working conditions of the electrical equipment are not met.

[0024] As a preferred technical solution of the present invention, the types of the detection sensor include but are not limited to a water level sensor, a temperature sensor, and a humidity sensor.

[0025] As a preferred technical solution of the present invention, the power supply module is composed of a photovoltaic power supply battery and a mains power supply module, and the power supply switching unit is provided with a DC input terminal and an AC input terminal, wherein the DC input terminal is connected to the photovoltaic power supply battery, and the AC input terminal is connected to the mains power supply module.

[0026] As a preferred technical solution of the present invention, the power supply switching unit is provided with an ambient light acquisition module, and the ambient light acquisition module is composed of a light sensor for acquiring ambient light conditions.

[0027] As a preferred technical solution of the present invention, a photovoltaic control system is provided, which uses the solar photovoltaic inverter described above.

[0028] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention realizes the conversion of electric energy through the inverter body to meet the electricity demand; by setting the power supply switching unit, photovoltaic power supply or AC power supply can be selected, which can ensure the all-weather use of electrical equipment and improve the convenience of use; by setting the idling protection module, the power consumption of electrical equipment can be reduced in scenarios that do not meet the use conditions, thereby avoiding energy waste. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the structure of the present invention;

[0030] Figure 2 It is a schematic diagram of the structure of the frequency converter body of the present invention;

[0031] Figure 3 This is a schematic diagram of the protection module structure of the present invention;

[0032] Figure 4 This is a schematic diagram of the structure of the function auxiliary module of the present invention;

[0033] Figure 5 This is a schematic diagram of the structure of the idling protection module of the present invention;

[0034] In the figure: 1. Inverter body; 2. Frequency conversion control module; 3. MPPT controller; 4. Protection module; 5. Function auxiliary module; 6. Speed ​​adjustment unit; 7. Idling protection module; 8. Power supply switching unit; 9. Photovoltaic power supply battery; 10. Mains power supply module; 11. Electrical equipment; 12. Ambient light acquisition module; 13. Rectifier; 14. Inverter; 15. Smoothing rectifier; 16. Filter; 17. Overvoltage protection unit; 18. Overcurrent protection unit; 19. Voltage monitoring unit; 20. Current monitoring unit; 21. Communication unit; 22. Signal conversion unit; 23. Detection sensor; 24. Signal processing circuit; 25. Control execution unit; 26. Temperature adjustment module; 27. Temperature sensor group; 28. Cooling fan unit. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] like Figures 1 to 5As shown, the present invention provides a solar photovoltaic inverter, comprising: an inverter body 1, the input end of the inverter body 1 is connected to the power supply module through the power supply switching unit 8, and the output end of the inverter body 1 is connected to the power-consuming device 11 to provide the power required for the power-consuming device 11 to work;

[0037] The inverter body 1 is composed of a frequency conversion control module 2, an MPPT controller 3, and a protection module 4. The frequency conversion control module 2 is connected to the MPPT controller 3 and the protection module 4. The inverter body 1 is connected to a temperature adjustment module 26.

[0038] The inverter body 1 is used for converting electric energy, converting DC power into AC power, and obtaining a three-phase AC output by turning on and off the switching device; the MPPT controller 3 is used to provide a control signal to the inverter body 1 to adjust the power supply voltage and frequency of the electrical equipment 11; the protection module 4 monitors the voltage and current in the circuit and takes effect in abnormal situations; the temperature adjustment module 26 is used to control the overall temperature of the inverter body 1 to prevent excessive temperature from affecting the normal operation of the equipment.

[0039] The frequency conversion control module 2 is composed of a rectifier 13, an inverter 14, a smoothing rectifier 15 and a filter 16, and the four are connected in sequence;

[0040] The rectifier 13 is connected to the power supply switching unit 8 to convert the current output by the power supply switching unit 8 into direct current. Common types of rectifiers 13 include single-phase and three-phase rectifiers, which can be selected according to actual application requirements.

[0041] The inverter 14 converts the DC power rectified by the rectifier 13 into AC power that meets the frequency of the power-consuming device 11, so as to supply the power grid or use it directly. The efficiency and stability of the inverter 14 are crucial to the performance of the entire system;

[0042] The smoothing rectifier 15 is used to smooth the voltage output by the rectifier 13, improve the power supply quality, and reduce the burden of the subsequent inverter 14;

[0043] The filter 16 is used to eliminate harmonics in the power line, ensure the quality of the output current, and prevent pollution to the power grid;

[0044] The temperature regulating module 26 is provided with a temperature sensor group 27 and a heat dissipation fan group 28, wherein the temperature sensor group 27 includes a plurality of groups of temperature sensors, and the heat dissipation fan group 28 includes a plurality of groups of fans;

[0045] The inverter body 1 is divided into three groups of areas from the inside to the outside according to the heating area, which are respectively recorded as the primary heating area, the secondary heating area, and the tertiary heating area; a temperature sensor is set in each heating area, and the temperature value of the corresponding area is taken, which is recorded as the primary area temperature value Q1, the secondary area temperature value Q2, and the tertiary area temperature value Q3;

[0046] The overheat risk coefficient G of the inverter body 1 is obtained according to the temperature value Q1 of the first zone, the temperature value Q2 of the second zone, and the temperature value Q3 of the third zone. r ; The overheating risk factor G r The calculation formula is as follows:

[0047]

[0048] In the formula, α, β, and γ are the weight coefficients of the first-level heating area, the second-level heating area, and the third-level heating area on the overall temperature, which are set by the staff, where α>β>γ; Q x , Q Y , Q Z They are the temperature values ​​of the first-level heating area, the second-level heating area, and the third-level heating area when they are working normally, which are obtained by detection; h, i, and j are the balancing values ​​of the first-level heating area, the second-level heating area, and the third-level heating area, which are the temperature value Q1 of the first area, the temperature value Q2 of the second area, and the temperature value Q3 of the third area, which are set by the staff;

[0049] The overheating risk factor G r The preset inverter overheat threshold G y For comparison, when G r >G y When the temperature is low, the cooling fan in the cooling fan unit 28 is started to cool down;

[0050] The protection module 4 is provided with an abnormal power-off judgment unit, which monitors the voltage and current states according to the voltage monitoring unit 19 and the current monitoring unit 20, and performs power-off processing when an abnormal situation occurs.

[0051] The MPPT controller 3 controls the inverter body 1 to always output at maximum power under any sunshine and temperature conditions. The MPPT controller 3 is provided with a speed regulating unit 6 ; the speed regulating unit 6 completes speed control of the electrical equipment 11 according to the frequency output of the MPPT controller 3 .

[0052] Among them, the protection module 4 includes an overvoltage protection unit 17 and an overcurrent protection unit 18. The overvoltage protection unit 17 monitors the output voltage of the inverter body 1 through the voltage monitoring unit 19, and automatically disconnects when the voltage is judged to be abnormal; the overcurrent protection unit 18 monitors the output current of the inverter body 1 through the current monitoring unit 20, and automatically disconnects when the current is judged to be abnormal.

[0053] Among them, the inverter body 1 is also provided with a functional auxiliary module 5, which includes a communication unit 21 and a signal conversion unit 22. The communication unit 21 is connected to the management terminal via a wireless signal; the signal conversion unit 22 converts the AC and DC voltages and currents in the inverter body 1 into digital quantities for display.

[0054] Among them, the inverter body 1 also includes an idling protection module 7, which is composed of a detection sensor 23, a signal processing circuit 24, and a control execution unit 25. The detection sensor 23 is used to detect the working environment of the electrical equipment 11. The signal processing circuit 24 receives the signal of the detection sensor 23 and determines whether the environment meets the working conditions of the electrical equipment 11. The control execution unit 25 takes action according to the analysis result of the signal processing circuit 24. When the working conditions of the electrical equipment 11 are not met, the operating power of the electrical equipment 11 is reduced or the electrical equipment 11 is shut down.

[0055] The types of the detection sensor 23 include but are not limited to a water level sensor, a temperature sensor, and a humidity sensor.

[0056] Among them, the power supply module is composed of a photovoltaic power supply battery 9 and a mains power supply module 10, and the power supply switching unit 8 is provided with a DC input terminal and an AC input terminal, wherein the DC input terminal is connected to the photovoltaic power supply battery 9, and the AC input terminal is connected to the mains power supply module 10.

[0057] Among them, the power supply switching unit 8 is provided with an ambient light collection module 12, which is composed of a light sensor for collecting ambient light conditions; when the light conditions meet the conditions for the photovoltaic system to generate electricity, the power supply interface adopts a photovoltaic power supply battery 9, and when the light conditions do not meet the conditions for the photovoltaic system to generate electricity, the power supply is converted to a municipal power supply module 10.

[0058] The present invention also discloses a photovoltaic control system, which uses the solar photovoltaic inverter described above.

[0059] The working principle and use process of the present invention:

[0060] The photovoltaic power supply battery 9 and the AC power supply module 10 together form a power supply module to provide power. The ambient light collection module 12 switches the power supply interface through the power supply switching unit 8 according to the lighting conditions; the inverter body 1 converts electrical energy, converts DC power into AC power, obtains three-phase AC output through the conduction and shutdown of the switching device, and supplies power to the electrical equipment 11.

[0061] The MPPT controller 3 can optimize the power output of the inverter body 1 to ensure that the maximum power output can be generated under different lighting conditions; the speed adjustment unit 6 receives commands from the MPPT controller 3 and automatically adjusts the speed of the motor to match the efficiency of photovoltaic power generation and the needs of the power grid.

[0062] The protection module 4 is protected by an overvoltage protection unit 17 and an overcurrent protection unit 18. By monitoring the voltage and current in the circuit, actions are taken when abnormal conditions such as overload and overvoltage occur to prevent damage to the equipment.

[0063] The function auxiliary module 5 includes a communication unit 21 and a signal conversion unit 22. The communication unit 21 supports remote data transmission and monitoring, so that the operator can remotely control and monitor the operating status of the photovoltaic inverter; the signal conversion unit 22 can convert some signals into digital displays to facilitate on-site observation by users.

[0064] The idling protection module 7 adaptively adjusts the type of the detection sensor 23 according to different electrical equipment 11. For example, when the electrical equipment 11 is a water pump, the detection sensor 23 is a water level sensor, which reduces the working power of the water pump when the water level is low; when the electrical equipment 11 is an air conditioner, the detection sensor 23 is a temperature sensor, which reduces the working power of the air conditioner when the temperature is under more suitable conditions.

[0065] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0066] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A solar photovoltaic inverter, comprising: an inverter body (1), wherein the input end of the inverter body (1) is connected to a power supply module via a power supply switching unit (8), and the output end of the inverter body (1) is connected to an electric device (11) to provide the electric power required for the electric device (11) to work; It is characterized in that The inverter body (1) is composed of a frequency conversion control module (2), an MPPT controller (3), and a protection module (4); the frequency conversion control module (2) is connected to the MPPT controller (3) and the protection module (4); the inverter body (1) is connected to a temperature adjustment module (26); The inverter body (1) is used for converting electric energy, converting DC power into AC power, and obtaining a three-phase AC output by turning on and off the switching device; The MPPT controller (3) is used to provide a control signal to the inverter body (1) to adjust the power supply voltage and frequency of the electrical equipment (11); The protection module (4) monitors the voltage and current in the circuit and takes effect in abnormal situations; The protection module (4) comprises an overvoltage protection unit (17) and an overcurrent protection unit (18); the overvoltage protection unit (17) monitors the output voltage of the inverter body (1) through a voltage monitoring unit (19), and automatically disconnects when the voltage is judged to be abnormal; the overcurrent protection unit (18) monitors the output current of the inverter body (1) through a current monitoring unit (20), and automatically disconnects when the current is judged to be abnormal; The temperature regulating module (26) is provided with a temperature sensor group (27) and a heat dissipation fan group (28), wherein the temperature sensor group (27) includes a plurality of groups of temperature sensors, and the heat dissipation fan group (28) includes a plurality of groups of fans; The inverter body (1) is divided into three groups of areas from the inside to the outside according to the heating area, which are respectively recorded as the first-level heating area, the second-level heating area, and the third-level heating area; a temperature sensor is arranged in each heating area, and the temperature value of the corresponding area is taken, which is recorded as the first-level area temperature value Q1, the second-level area temperature value Q2, and the third-level area temperature value Q3; The overheat risk coefficient G of the inverter body (1) is obtained based on the first-level area temperature value Q1, the second-level area temperature value Q2, and the third-level area temperature value Q3. r ; The overheating risk factor G r The calculation formula is as follows: In the formula, α, β, and γ are the weight coefficients of the first-level heating area, the second-level heating area, and the third-level heating area on the overall temperature, which are set by the staff, where α>β>γ; Q x , Q Y , Q Z They are the temperature values ​​of the first-level heating area, the second-level heating area, and the third-level heating area when they are working normally, which are obtained by detection; h, i, and j are the balancing values ​​of the first-level area temperature value Q1, the second-level area temperature value Q2, and the third-level area temperature value Q3, which are set by the staff; The overheating risk factor G r The preset inverter overheat threshold G y For comparison, when G r >G y When the temperature is reduced, the heat dissipation fan in the heat dissipation fan unit (28) is started to cool down.

2. A solar photovoltaic inverter according to claim 1, characterized in that: The frequency conversion control module (2) comprises a rectifier (13), an inverter (14), a smoothing rectifier (15) and a filter (16), and the four are connected in sequence; The rectifier (13) is connected to the power supply switching unit (8) to convert the current output by the power supply switching unit (8) into direct current; The inverter (14) converts the direct current rectified by the rectifier (13) into alternating current that meets the frequency of the electrical equipment (11); The smoothing rectifier (15) is used to smooth the voltage output by the rectifier (13); The filter (16) is used to eliminate harmonics in the power line.

3. A solar photovoltaic inverter according to claim 1, characterized in that: The MPPT controller (3) controls the inverter body (1) to always output at maximum power under any sunshine conditions and temperature conditions. The MPPT controller (3) is provided with a speed regulating unit (6); the speed regulating unit (6) completes speed regulation control of the electrical equipment (11) according to the frequency output of the MPPT controller (3).

4. A solar photovoltaic inverter according to claim 1, characterized in that: The inverter body (1) is also provided with a functional auxiliary module (5), the functional auxiliary module (5) comprising a communication unit (21) and a signal conversion unit (22), the communication unit (21) being connected to a management terminal via a wireless signal; the signal conversion unit (22) converts the AC and DC voltages and currents in the inverter body (1) into digital quantities for display.

5. A solar photovoltaic inverter according to claim 1, characterized in that: The inverter body (1) also includes an idling protection module (7), which is composed of a detection sensor (23), a signal processing circuit (24), and a control execution unit (25), wherein the detection sensor (23) is used to detect the working environment of the electrical equipment (11), the signal processing circuit (24) receives the signal of the detection sensor (23), and determines whether the environment meets the working conditions of the electrical equipment (11), and the control execution unit (25) takes action according to the analysis result of the signal processing circuit (24), and reduces the operating power of the electrical equipment (11) or shuts down when the working conditions of the electrical equipment (11) are not met.

6. A solar photovoltaic inverter according to claim 5, characterized in that: The types of the detection sensor (23) include but are not limited to a water level sensor, a temperature sensor, and a humidity sensor.

7. A solar photovoltaic inverter according to claim 1, characterized in that: The power supply module is composed of a photovoltaic power supply battery (9) and a mains power supply module (10), and the power supply switching unit (8) is provided with a DC input end and an AC input end, wherein the DC input end is connected to the photovoltaic power supply battery (9), and the AC input end is connected to the mains power supply module (10).

8. A solar photovoltaic inverter according to claim 1, characterized in that: The power supply switching unit (8) is provided with an ambient light acquisition module (12), and the ambient light acquisition module (12) is composed of a light sensor and is used to acquire ambient light conditions.

9. A photovoltaic control system, characterized in that: The invention relates to a solar photovoltaic inverter as claimed in any one of claims 1 to 8.

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