Photovoltaic inverter power supply control system and method

Abstract

The invention discloses a photovoltaic inverter power supply control system and method, belonging to the technical field of photovoltaic inverters, comprising a photovoltaic power generation component, a DC battery electrically connected to the photovoltaic power generation component, a plurality of inverter power supply components electrically connected to the DC battery and a general control system, wherein the general control system comprises a first voltage monitoring module, a voltage control module, a voltage adjustment module, a temperature detection module, a low temperature judgment module, a temperature early warning module and a cycle start-stop module, and the invention has the effect of automatically reducing the operation of the inverter power supply when there is a risk of overheating of the inverter power supply, thereby effectively reducing the possibility of overheating of the inverter power supply.

Description

Technical Field

[0001] The present invention relates to the field of photovoltaic inverters, and in particular to a photovoltaic inverter power supply control system and method. Background Art

[0002] The inverter power supply includes an inverter, whose main function is to convert the input DC power into AC power output. In the photovoltaic field, photovoltaic power generation components will generate variable DC power, which needs to be converted into AC power by an inverter power supply before it can be used as mains power. The common process is that the photovoltaic solar panel receives solar energy and converts it into electrical energy, which is then transmitted to the DC battery through the safety circuit, voltage stabilization circuit, etc. The DC battery transmits the DC power to the inverter power supply and converts it into AC power that can be used for mains power. Compared with ordinary inverter power supplies, the DC input voltage of the photovoltaic inverter power supply is unstable and varies greatly, usually between 100V and 1000V. The inverter power supply needs to avoid overheating during operation. Overheating of the inverter power supply will lead to performance degradation and may even cause equipment damage.

[0003] The prior art can refer to the Chinese invention patent with application publication number CN113437762A, which discloses a photovoltaic inverter power supply system, including: a main power supply, including a transformer, the transformer including a primary high-voltage coil connected to the positive output end of the bus Bus and a plurality of drive power supply coils; a power circuit whose output end is connected to the power grid, including an inverter unit and a boost unit, the inverter unit and the boost unit including a plurality of switch tubes; a drive circuit including a plurality of drive units connected to the plurality of drive power supply coils to connect the main power supply to the gate of each switch tube.

[0004] The above-mentioned existing technical solutions have the following defects: since photovoltaic power generation is greatly affected by the environment, the power generation is very unstable. When the photovoltaic power generation is large, the input power of the inverter is large, and the inverter workload is large. In addition, when the photovoltaic power generation is large, the ambient temperature is usually high, and the inverter is prone to overheating, so it is necessary to avoid overheating of the inverter as much as possible. Summary of the invention

[0005] In order to reduce the possibility of overheating of the inverter power supply as much as possible, the present application provides a photovoltaic inverter power supply control system and method.

[0006] On the one hand, the photovoltaic inverter power supply control system provided by the present application adopts the following technical solution:

[0007] A photovoltaic inverter power supply control system, comprising a photovoltaic power generation component, a DC battery electrically connected to the photovoltaic power generation component, a plurality of inverter power supply components electrically connected to the DC battery, and a general control system, wherein the general control system comprises a first voltage monitoring module, a voltage control module, a voltage adjustment module, a temperature detection module, a low temperature judgment module, a temperature early warning module, and a cycle start-stop module;

[0008] The first voltage monitoring module detects a first voltage value of the direct current output by the photovoltaic power generation assembly, and transmits the first voltage value to the voltage control module;

[0009] The voltage control module is preset with a preset voltage table, the first preset voltage table includes a plurality of preset voltage ranges and voltage reduction level signals, the preset voltage ranges and the voltage reduction level signals are in one-to-one correspondence, the voltage control module compares the first voltage value according to the first preset voltage table, selects the voltage reduction level signal and the expected voltage reduction voltage range according to the preset voltage range in which the first voltage value is located, and transmits the voltage reduction level signal to the voltage adjustment module;

[0010] The voltage adjustment module includes a plurality of battery relays arranged between the photovoltaic power generation assembly and the DC storage battery and a DC transformer connected in series to each battery relay. Different DC transformers have different step-down ranges. The voltage adjustment module controls the opening and closing of the battery relay according to the received step-down level signal.

[0011] The temperature detection module detects the temperature of each inverter power supply component, numbers the temperature value according to the inverter power supply component and transmits it to the low temperature judgment module and the temperature early warning module;

[0012] The low temperature judgment module is preset with a low temperature preset value, and the low temperature judgment module compares the temperature value with the low temperature preset value. If all temperature values ​​are lower than the low temperature preset value, the voltage control module is controlled to stop working and transmit a voltage reduction level signal of the highest voltage reduction range to the voltage adjustment module;

[0013] The temperature warning module is preset with a temperature warning value and a preset time. The temperature warning module compares the temperature value with the temperature warning value. When only one temperature value is higher than the temperature warning value, the inverter power supply component corresponding to the number of the temperature value is controlled to stop working and stop receiving the temperature value, and timing is performed at the same time. When the number of temperature values ​​higher than the temperature warning value is greater than or equal to two, a start signal and the number of the temperature value with the highest value are transmitted to the cycle start and stop module, and the temperature value is stopped. Timing is performed at the same time. After the timing reaches the preset time, the temperature value is received again;

[0014] The cyclic start and stop module is preset with an inverter power supply component sequence and a set time. After receiving the start signal and the temperature value number, the cyclic start and stop module controls the inverter power supply component corresponding to the temperature value number to stop working, and starts with the inverter power supply component, and controls the inverter power supply component to stop working and start after the set time according to the inverter power supply component sequence.

[0015] By adopting the above scheme, the overall control system monitors the operation of the photovoltaic system in real time. When the DC voltage output by the photovoltaic power generation component increases, the overall control system accesses the DC transformer according to the DC voltage output by the photovoltaic power generation component, adjusts the voltage of the DC battery, and makes the DC voltage received by the inverter component as small as possible, thereby reducing the input power and operating load of the inverter component, and reducing the possibility of overheating of the inverter component. If the photovoltaic power generation component has a high power generation efficiency due to weather and other reasons at that time, it makes it difficult to reduce the voltage of the DC battery, and the inverter component is easy to heat up. After the temperature of any inverter component rises to the warning value, the overall control system will first suspend the operation of the inverter component with a temperature value higher than the warning value. If the temperature of other inverter components also rises to the warning value, the overall control system will allow the inverter components to work alternately, ensuring that only one inverter component is suspended to ensure work efficiency, while avoiding the inverter component from continuing to work at high temperature, which can effectively reduce the possibility of overheating of the inverter.

[0016] Preferably, the overall control system includes a second voltage monitoring module and a fault processing module;

[0017] The second voltage monitoring module detects a second voltage value of the DC power output by the DC battery, and transmits the second voltage value to the voltage control module;

[0018] The first preset voltage table of the voltage control module also includes an expected step-down voltage range, and the preset voltage range, the step-down level signal and the expected step-down voltage range all correspond to each other. The voltage control module compares the second voltage value with the expected step-down voltage range, and transmits a step-down fault signal to the fault processing module if the second voltage value is outside the selected expected step-down voltage range;

[0019] The voltage adjustment module also includes an emergency relay arranged between the photovoltaic power generation assembly and the DC battery;

[0020] After receiving the step-down fault signal, the fault processing module controls the voltage control module to stop working, the fault processing module sends a fault alarm signal, and controls the voltage adjustment module to disconnect the current battery relay and close the battery relay corresponding to the DC transformer converter that is closest to the current step-down range and greater than the current step-down range. If the current step-down range is the maximum step-down range, all battery relays are disconnected and the emergency relay is closed.

[0021] By adopting the above solution, the main control system will also monitor the DC voltage output by the DC battery. If the DC voltage output by the DC battery is not within the required output voltage range of the connected DC transformer, a circuit failure occurs. The main control system will try to switch the connected DC transformer while issuing an alarm to ensure the normal operation of the system as much as possible.

[0022] Preferably, the overall control system further includes a temperature alarm module;

[0023] The temperature detection module sends the numbered temperature value to the temperature alarm module;

[0024] The temperature alarm module is preset with a temperature alarm value, and the temperature alarm module compares the temperature value with the temperature alarm value. When only one temperature value is higher than the temperature alarm value, the temperature alarm module transmits the number of the temperature value to the cycle start and stop module. When the number of temperature values ​​higher than the temperature alarm value is greater than or equal to two, the temperature alarm module controls the inverter power supply components corresponding to all temperature values ​​higher than the temperature alarm value to stop working, and transmits the numbers of all temperature values ​​higher than the temperature alarm value to the cycle start and stop module, and the temperature alarm module sends a temperature alarm signal.

[0025] When the cyclic start-stop module receives the number and the start signal, it locks the corresponding inverter assembly according to the received number, and skips the locked inverter assembly when controlling the inverter assembly according to the inverter assembly sequence.

[0026] By adopting the above scheme, when the temperature of the inverter power component reaches the alarm value, the inverter power component is close to overheating. In addition to issuing an alarm, the main control system will also force the inverter power component to stop working, preventing the inverter power component that is close to overheating from working when the inverter power components are started alternately.

[0027] Preferably, the overall control system further includes a current monitoring module and a current early warning module;

[0028] The current monitoring module detects the current output by the DC battery and transmits the current value to the current early warning module;

[0029] The current warning module is preset with a current warning value, and the current warning module compares the current value with the current warning value, and transmits a current warning signal to the voltage adjustment module when the current value exceeds the current warning value;

[0030] After the voltage adjustment module receives the voltage reduction level signal, if it receives the current warning signal, it calls the preset voltage table of the voltage control module, queries the corresponding preset voltage reduction range according to the currently received voltage reduction level signal and the preset voltage table, and selects the preset voltage reduction range that is closest to the queried preset voltage reduction range and greater than the queried preset voltage reduction range, and controls the corresponding battery relay to close according to the selected preset voltage reduction range.

[0031] By adopting the above solution, the main control system will also monitor the DC current output by the DC battery. If the DC current value exceeds the warning value, it proves that the voltage of the DC battery is too small, resulting in excessive DC current, which is prone to safety accidents. The main control system switches the connected DC transformer to increase the voltage of the DC battery, thereby reducing the current output by the DC battery.

[0032] Preferably, a solar refrigerator is arranged near the inverter power supply assembly, and the overall control system further comprises a refrigeration control module;

[0033] The refrigeration control module is connected to the solar refrigerator and receives a temperature alarm signal. After receiving the temperature alarm signal, the refrigeration control module controls the solar refrigerator to work.

[0034] By adopting the above solution, since there is sufficient solar energy at the location of the photovoltaic power generation component and the inverter power supply is prone to overheating when the solar energy is strong enough, the solar refrigerator can use the powerful solar energy and the cheap electricity produced by the photovoltaic power generation component to perform cooling and cooling, which can effectively reduce the temperature of the working environment of the inverter power supply component.

[0035] Preferably, the refrigerant water pipeline of the solar refrigerator is fixedly connected to a plurality of refrigeration pipelines, the number of the refrigeration pipelines is the same as the number of the inverter power supply components, each refrigeration pipeline is close to an inverter power supply component, and each refrigeration pipeline is fixedly connected to a solenoid valve;

[0036] The temperature alarm module sends a temperature alarm signal and a temperature value number to the refrigeration control module;

[0037] The refrigeration control module is preset with a number correspondence table, which includes temperature value numbers and solenoid valve numbers. After the refrigeration control module receives the temperature alarm signal and the temperature value number, it searches for the corresponding solenoid valve number in the number correspondence table according to the temperature value number. The refrigeration control module controls the solenoid valve to open according to the searched solenoid valve number.

[0038] By adopting the above solution, the cooling pipe can allow the low-temperature refrigerant water generated by the solar refrigerator to flow through, which can more effectively reduce the temperature of the nearby inverter components. The overall control system can determine which cooling pipe needs to be opened based on the current temperature value of the inverter component, so as to connect as few cooling pipes as possible to the solar refrigerator, thereby maximizing the cooling efficiency of the high-temperature inverter components and effectively saving energy.

[0039] Preferably, the refrigeration control module controls the solenoid valve to be opened and then locks the solenoid valve. When the solenoid valve is locked, the refrigeration control module does not close the locked solenoid valve. At the same time, the refrigeration control module transmits the monitoring signal and the received temperature value number to the temperature early warning module. After receiving the unlocking signal and the temperature value number, the refrigeration control module releases the lock of the solenoid valve corresponding to the temperature value number and closes the solenoid valve at the same time.

[0040] When the temperature warning module receives the monitoring signal and the temperature value number, it monitors the temperature value of the inverter power supply component corresponding to the number, and transmits an unlocking signal and the temperature value number to the refrigeration control module when the monitored temperature value is lower than the temperature warning value.

[0041] By adopting the above solution, in order to avoid repeated opening and closing of the solenoid valve, the main control system will lock the opened solenoid valve and will not close the solenoid valve until the temperature of the inverter power supply component drops to the temperature warning value.

[0042] Preferably, it also includes a host terminal and a mobile terminal, and the overall control system also includes a wireless communication module, which receives the temperature alarm signal output by the temperature alarm module and sends the temperature alarm signal to the host terminal and the mobile terminal.

[0043] By adopting the above solution, the overall control system will send alarm signals to the host terminal and mobile terminal via wireless signals, making it convenient for users to understand the situation in a timely manner.

[0044] Preferably, a cooling fan is arranged near the inverter power supply assembly, and the temperature warning module is connected to the cooling fan. If any temperature value in the comparison result of the temperature warning module is higher than the temperature warning value, the temperature warning module controls the cooling fan to start.

[0045] By adopting the above solution, the cooling fan is used as a common cooling device, and the overall control system can also be controlled according to the current temperature of the inverter power supply component.

[0046] On the other hand, a photovoltaic inverter power supply control method provided in the present application adopts the following technical solution:

[0047] A photovoltaic inverter power supply control method, using any of the photovoltaic inverter power supply control systems described above, comprises the following steps:

[0048] Set preset voltage meter, low temperature preset value, temperature warning value, preset time, inverter power supply component sequence and set time;

[0049] Monitor the voltage value of the DC power output by the photovoltaic power generation components;

[0050] Monitor the temperature value of each inverter power component;

[0051] Determine the battery relay that should be closed according to the preset voltage meter and the voltage value of the direct current output by the photovoltaic power generation assembly, and close the battery relay;

[0052] After the battery relay is closed, the DC transformer converter connected in series with it is connected to the front-end circuit of the DC battery;

[0053] Compare the temperature value of the inverter power supply component with the low temperature preset value and the temperature warning value;

[0054] If all temperature values ​​are lower than the low temperature preset value, the battery relay of the DC transformer converter with the highest step-down range is closed, and the comparison of voltage values ​​is stopped at the same time;

[0055] If only one temperature value is higher than the temperature warning value, the inverter power supply component controlling the source of the temperature value stops working, and the comparison is performed again after a preset time;

[0056] If the number of temperature values ​​higher than the temperature warning value is greater than or equal to two, the inverter power supply component corresponding to the temperature value with the highest numerical value is controlled to stop working for a set time, and the inverter power supply component is controlled to start after stopping working for the set time according to the inverter power supply component sequence.

[0057] By adopting the above scheme, when the DC voltage output by the photovoltaic power generation component increases, the main control system makes the DC voltage received by the inverter component as small as possible, thereby reducing the input power and operating load of the inverter component and reducing the possibility of overheating of the inverter component. After the temperature of any inverter component rises to the warning value, the main control system will first suspend the operation of the inverter component with a temperature value higher than the warning value. If the temperature of other inverter components also rises to the warning value, the main control system will allow the inverter components to work alternately. While ensuring that only one inverter component is suspended to ensure work efficiency, it is also possible to avoid the inverter component from continuing to work at high temperatures, which can effectively reduce the possibility of overheating of the inverter.

[0058] In summary, the present invention has the following beneficial effects:

[0059] 1. By making the DC voltage received by the inverter as small as possible, the input power and operating load of the inverter are reduced, reducing the possibility of overheating of the inverter.

[0060] 2. While ensuring working efficiency, let the inverter power components work alternately to avoid the inverter power components working continuously at high temperature, which can effectively reduce the possibility of inverter power overheating. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 This is a system block diagram of a photovoltaic inverter power supply control system according to an embodiment of the present application.

[0062] Figure 2 This is a schematic diagram of a solar refrigerator, a refrigeration pipeline and a solenoid valve in a photovoltaic inverter power supply control system according to an embodiment of the present application;.

[0063] Figure 3 This is a module block diagram of a photovoltaic inverter power supply control system overall control system according to the first embodiment of the present application;

[0064] Figure 4 This is a system block diagram of a wireless communication module, a host terminal and a mobile terminal of a photovoltaic inverter power supply control system according to an embodiment of the present application.

[0065] Description of reference numerals:

[0066] 1. General control system; 11. First voltage monitoring module; 111. Second voltage monitoring module; 12. Voltage control module; 121. Voltage adjustment module; 122. Fault handling module; 13. Temperature detection module; 131. Low temperature judgment module; 14. Temperature warning module; 15. Cycle start and stop module; 16. Temperature alarm module; 17. Current monitoring module; 171. Current warning module; 18. Refrigeration control module; 19. Wireless communication module; 2. Photovoltaic power generation component; 3. DC battery; 31. Battery relay; 32. DC transformer converter; 33. Emergency relay; 4. Inverter power supply component; 5. Solar refrigerator; 51. Refrigeration pipeline; 52. Solenoid valve; 6. Host terminal; 7. Mobile terminal; 8. Cooling fan. DETAILED DESCRIPTION

[0067] The following is combined with Figure 1-4 This application is described in further detail.

[0068] Embodiment 1

[0069] The present application embodiment discloses a photovoltaic inverter power supply control system, such as Figure 1As shown, it includes a photovoltaic power generation component 2, a DC battery 3 electrically connected to the photovoltaic power generation component 2, a plurality of inverter power components 4 electrically connected to the DC battery 3, a solar refrigerator 5 electrically connected to the inverter power component 4, a cooling fan 8 electrically connected to the inverter power component 4, and a general control system 1. The cooling fan 8 is arranged near the inverter power component 4. A plurality of battery relays 31, a DC transformer 32 connected in series to each battery relay 31, and an emergency relay 33 are arranged between the photovoltaic power generation component 2 and the DC battery 3. Different DC transformers 32 have different step-down ranges, and the emergency relay 33 is not connected in series to any DC transformer 32. The DC transformer 32 can use the AH8672A DC transformer conversion chip. The solar refrigerator 5 performs cooling by using thermal energy and electrical energy. In the present application, the solar refrigerator 5 can use an absorption refrigerator. Since there is sufficient solar energy at the location of the photovoltaic power generation component 2 and the inverter power supply is prone to overheating when the solar energy is strong enough, the solar refrigerator 5 can just use the powerful solar energy and the cheap electricity produced by the photovoltaic power generation component 2 to perform cooling and cooling, which can effectively reduce the temperature of the working environment of the inverter power supply component 4.

[0070] like Figure 1 and Figure 2 As shown, the refrigerant water pipeline of the solar refrigerator 5 is fixedly connected to a plurality of refrigeration pipelines 51, the number of the refrigeration pipelines 51 is the same as the number of the inverter power components 4, each refrigeration pipeline 51 is close to an inverter power component 4, and a solenoid valve 52 is fixedly connected to each refrigeration pipeline 51. The refrigeration pipeline 51 allows the low-temperature refrigerant water generated by the solar refrigerator 5 to flow through, thereby more effectively reducing the temperature of the nearby inverter power components 4.

[0071] like Figure 3 and Figure 4 As shown, the overall control system 1 includes a first voltage monitoring module 11, a second voltage monitoring module 111, a voltage control module 12, a voltage adjustment module 121, a fault handling module 122, a temperature detection module 13, a low temperature judgment module 131, a temperature early warning module 14, a cycle start and stop module 15, a temperature alarm module 16, a current monitoring module 17, a current early warning module 171, a refrigeration control module 18 and a wireless communication module 19.

[0072] like Figure 3 As shown, the first voltage monitoring module 11 detects a first voltage value of the DC power output by the photovoltaic power generation assembly 2, and transmits the first voltage value to the voltage control module 12. The second voltage monitoring module 111 detects a second voltage value of the DC power output by the DC battery 3, and transmits the second voltage value to the voltage control module 12.

[0073] like Figure 3As shown, the current monitoring module 17 detects the current output by the DC battery 3 and transmits the current value to the current warning module 171. The current warning module 171 is preset with a current warning value, and the current warning module 171 compares the current value with the current warning value, and transmits a current warning signal to the voltage adjustment module 121 when the current value exceeds the current warning value.

[0074] like Figure 3 As shown, the voltage control module 12 is preset with a preset voltage table, and the first preset voltage table includes multiple preset voltage ranges, step-down level signals and expected step-down voltage ranges, and the preset voltage ranges, step-down level signals and expected step-down voltage ranges are all in one-to-one correspondence. The voltage control module 12 compares the first voltage value according to the first preset voltage table, selects the step-down level signal and the expected step-down voltage range according to the preset voltage range in which the first voltage value is located, and transmits the step-down level signal to the voltage adjustment module 121. The voltage control module 12 compares the second voltage value with the expected step-down voltage range, and if the second voltage value is outside the selected expected step-down voltage range, the step-down fault signal is transmitted to the fault processing module 122.

[0075] like Figure 3 As shown, the voltage adjustment module 121 includes a plurality of battery relays 31 arranged between the photovoltaic power generation assembly 2 and the DC battery 3 and a DC transformer 32 connected in series to each battery relay 31. Different DC transformers 32 have different step-down ranges. The voltage adjustment module 121 controls the opening and closing of the battery relay 31 according to the received step-down level signal. After the voltage adjustment module 121 receives the step-down level signal, if it receives the current warning signal, it calls the preset voltage table of the voltage control module 12, queries the corresponding preset step-down range according to the currently received step-down level signal and the preset voltage table, and selects the preset step-down range that is closest to the preset step-down range and greater than the preset step-down range, and controls the corresponding battery relay 31 to close according to the selected preset step-down range. If the current value of the DC power exceeds the warning value, it proves that the voltage of the DC battery 3 is too small at this time, resulting in excessive DC current, which is prone to safety accidents. The voltage adjustment module 121 switches the connected DC transformer 32 to increase the voltage of the DC battery 3, thereby reducing the current output by the DC battery 3.

[0076] like Figure 3 and Figure 4As shown, after receiving the step-down fault signal, the fault processing module 122 controls the voltage control module 12 to stop working, and the fault processing module 122 transmits a fault alarm signal to the wireless communication module 19, and controls the voltage adjustment module 121 to disconnect the current battery relay 31 and close the battery relay 31 corresponding to the DC transformer 32 that is closest to the current step-down range and greater than the current step-down range. If the current step-down range is the maximum step-down range, all battery relays 31 are disconnected and the emergency relay 33 is closed. If the DC voltage output by the DC battery 3 is not within the output voltage range of the connected DC transformer 32, then the circuit fails at this time. The fault processing module 122 will try to switch the connected DC transformer 32 while issuing an alarm to ensure that the system can operate normally as much as possible. If all DC transformers 32 cannot be connected, the fault processing module 122 will directly connect the photovoltaic power generation component 2 to the DC battery 3 through the emergency relay 33.

[0077] like Figure 3 As shown, the temperature detection module 13 detects the temperature of each inverter power supply component 4, numbers the temperature value according to the inverter power supply component 4 and transmits it to the low temperature judgment module 131 and the temperature warning module 14. The low temperature judgment module 131 is preset with a low temperature preset value, and the low temperature judgment module 131 compares the temperature value with the low temperature preset value. If all temperature values ​​are lower than the low temperature preset value, the voltage control module 12 is controlled to stop working and transmit the voltage reduction level signal of the highest voltage reduction range to the voltage adjustment module 121.

[0078] like Figure 3 As shown, the temperature warning module 14 is preset with a temperature warning value and a preset time. The temperature warning module 14 compares the temperature value with the temperature warning value. When any temperature value is higher than the temperature warning value, the temperature warning module 14 controls the cooling fan 8 to start. When only one temperature value is higher than the temperature warning value, the inverter power supply component 4 corresponding to the number of the temperature value is controlled to stop working and stop receiving the temperature value, and timing is performed at the same time. When the number of temperature values ​​higher than the temperature warning value is greater than or equal to two, the start signal and the number of the temperature value with the highest value are transmitted to the cycle start and stop module 15 and the temperature value is stopped. Timing is performed at the same time, and the temperature value is received again after the timing reaches the preset time. When the temperature warning module 14 receives the monitoring signal and the temperature value number, it monitors the temperature value of the inverter power supply component 4 corresponding to the number. When the monitored temperature value is lower than the temperature warning value, the unlocking signal and the number of the temperature value are transmitted to the refrigeration control module 18.

[0079] like Figure 3 and Figure 4As shown, the temperature alarm module 16 is preset with a temperature alarm value, and the temperature alarm value is greater than the temperature warning value. The temperature alarm module 16 compares the temperature value with the temperature alarm value. When only one temperature value is higher than the temperature alarm value, the temperature alarm module 16 transmits the number of the temperature value to the cycle start and stop module 15. When the number of temperature values ​​higher than the temperature alarm value is greater than or equal to two, the temperature alarm module 16 controls the inverter power supply components 4 corresponding to all temperature values ​​higher than the temperature alarm value to stop working, and transmits the numbers of all temperature values ​​higher than the temperature alarm value to the cycle start and stop module 15. The temperature alarm module 16 transmits the temperature alarm signal to the refrigeration control module 18 and the wireless communication module 19. The temperature alarm module 16 sends the temperature alarm signal and the temperature value number to the refrigeration control module 18.

[0080] like Figure 3 As shown, the cyclic start-stop module 15 is preset with the sequence and set time of the inverter power assembly 4. After receiving the start signal and the number of the temperature value, the cyclic start-stop module 15 controls the inverter power assembly 4 corresponding to the number of the temperature value to stop working, and starts with the inverter power assembly 4, and controls the inverter power assembly 4 to stop working and start after the set time according to the sequence of the inverter power assembly 4. When the cyclic start-stop module 15 receives the number and the start signal, it locks the corresponding inverter power assembly 4 according to the received number, and skips the locked inverter power assembly 4 when controlling the inverter power assembly 4 according to the sequence of the inverter power assembly 4. When the temperature of the inverter power assembly 4 reaches the alarm value, the inverter power assembly 4 is close to overheating. In addition to issuing an alarm, the general control system 1 will also force the inverter power assembly 4 to stop working, and prevent the inverter power assembly 4 that is close to overheating from working when the inverter power assembly 4 is alternately started.

[0081] like Figure 2 and Figure 3As shown, the refrigerant water pipeline of the solar refrigerator 5 is fixedly connected to a plurality of refrigeration pipes 51, the number of which is the same as the number of the inverter power supply components 4, each refrigeration pipe 51 is close to an inverter power supply component 4, and each refrigeration pipe 51 is fixedly connected to a solenoid valve 52. The refrigeration control module 18 is connected to the solar refrigerator 5, and the refrigeration control module 18 is preset with a number correspondence table, which includes the temperature value number and the solenoid valve 52 number. After receiving the temperature alarm signal and the temperature value number, the refrigeration control module 18 controls the solar refrigerator 5 to work, and searches for the corresponding solenoid valve 52 number in the number correspondence table according to the temperature value number, and the refrigeration control module 18 controls the solenoid valve 52 to open according to the searched solenoid valve 52 number. The refrigeration control module 18 controls the solenoid valve 52 to open and then locks the solenoid valve 52. When the solenoid valve 52 is locked, the refrigeration control module 18 does not close the locked solenoid valve 52. At the same time, the refrigeration control module 18 transmits the monitoring signal and the received temperature value number to the temperature warning module 14. After receiving the unlocking signal and the temperature value number, the refrigeration control module 18 unlocks the solenoid valve 52 corresponding to the temperature value number and closes the solenoid valve 52 at the same time.

[0082] The refrigeration pipe 51 allows the low-temperature refrigerant water generated by the solar refrigerator 5 to flow through, more effectively reducing the temperature of the nearby inverter power assembly 4. The overall control system 1 can determine which refrigeration pipe 51 needs to be opened by the current temperature value of the inverter power assembly 4, so that as few refrigeration pipes 51 as possible are connected to the solar refrigerator 5, while maximizing the cooling efficiency of the high-temperature inverter power assembly 4, and effectively saving energy. At the same time, in order to avoid repeatedly opening and closing the solenoid valve 52, the overall control system 1 will lock the opened solenoid valve 52 until the temperature of the inverter power assembly 4 drops to the temperature warning value before closing the solenoid valve 52.

[0083] like Figure 4 As shown, the photovoltaic inverter power supply control system also includes a host terminal 6 and a mobile terminal 7. The host terminal 6 is set on the host of the administrator, and the mobile terminal 7 is set on a mobile device such as a mobile phone or a tablet. The wireless communication module 19 receives the fault alarm signal output by the fault processing module 122 and the temperature alarm signal output by the temperature alarm module 16, and sends the fault alarm signal and the temperature alarm signal to the host terminal 6 and the mobile terminal 7. The user can learn about the alarm information of the inverter power supply in a timely manner through the host terminal 6 and the mobile terminal 7.

[0084] The implementation principle of a photovoltaic inverter power control system in the embodiment of the present application is as follows: the general control system 1 monitors the operation of the photovoltaic system in real time. When the DC voltage output by the photovoltaic power generation component 2 increases, the general control system 1 accesses the DC transformer 32 according to the DC voltage output by the photovoltaic power generation component 2, adjusts the voltage of the DC battery 3, and makes the DC voltage received by the inverter power component 4 as small as possible, thereby reducing the input power and operating load of the inverter power component 4, and reducing the possibility of overheating of the inverter power component 4. If the photovoltaic power generation component 2 has a high power generation efficiency due to weather and other reasons at that time, it is difficult to reduce the voltage of the DC battery 3, and the inverter power component 4 is easy to heat up. After the temperature of any inverter power component 4 rises to the warning value, the general control system 1 will first suspend the operation of the inverter power component 4 with a temperature value higher than the warning value. If the temperature of other inverter power components 4 also rises to the warning value later, the general control system 1 will allow the inverter power components 4 to work alternately, ensuring that only one inverter power component 4 is suspended to ensure work efficiency, while avoiding the inverter power component 4 from continuing to work at high temperature, which can effectively reduce the possibility of overheating of the inverter power.

[0085] Embodiment 2

[0086] The present application embodiment discloses a photovoltaic inverter power supply control method, using a photovoltaic inverter power supply control system of embodiment 1, and the specific steps are as follows:

[0087] S1. Set the preset voltage table, low temperature preset value, temperature warning value, temperature alarm value, number correspondence table, current warning value, preset time, inverter power supply component 4 sequence and set time.

[0088] S2, monitoring the voltage value of the direct current output by the photovoltaic power generation assembly 2 and the voltage value and current value of the direct current output by the direct current storage battery 3.

[0089] S3, monitoring the temperature value of each inverter power supply component 4.

[0090] S4. Determine the battery relay 31 that should be closed according to the preset voltage meter and the voltage value of the direct current output by the photovoltaic power generation assembly 2, and close the battery relay 31.

[0091] S41, after the battery relay 31 is closed, the DC transformer 32 connected in series with the battery relay 31 is connected to the front end circuit of the DC battery 3.

[0092] S5. Compare the temperature value of the inverter power supply assembly 4 with the low temperature preset value, the temperature early warning value and the temperature alarm value.

[0093] S51. If all temperature values ​​are lower than the low temperature preset value, the battery relay 31 of the DC converter 32 in the highest step-down range is closed, and the voltage value comparison is stopped at the same time.

[0094] S52: If only one temperature value is higher than the temperature warning value, the inverter power supply component 4 of the temperature value source is controlled to stop working, and a comparison is performed again after a preset time.

[0095] S53, if the number of temperature values ​​higher than the temperature warning value is greater than or equal to two, the inverter power supply assembly 4 corresponding to the temperature value with the highest numerical value is controlled to stop working for a set time, and the inverter power supply assembly 4 is controlled to stop working for the set time and then start according to the sequence of the inverter power supply assembly 4.

[0096] S54, if only one temperature value is higher than the temperature alarm value, the inverter power supply assembly 4 corresponding to the temperature value is forced to stop working, and the solar refrigerator 5 is started, and the solenoid valve 52 corresponding to the stopped inverter power supply assembly 4 is searched according to the number correspondence table and opened.

[0097] S55. If the number of temperature values ​​higher than the temperature alarm value is greater than or equal to two, all inverter power supply components 4 corresponding to the temperature values ​​higher than the temperature alarm value are forced to stop working, and the solar refrigerator 5 is started, and the solenoid valve 52 corresponding to the inverter power supply component 4 that has stopped working is found according to the number correspondence table and opened.

[0098] S56 , after the solenoid valve 52 is opened, the solenoid valve 52 is locked to prevent the solenoid valve 52 from closing; when the temperature value is lower than the temperature warning value, the solenoid valve 52 is unlocked to close the solenoid valve 52 .

[0099] S6. Monitor whether the voltage of the DC power output by the DC battery 3 is outside the selected expected step-down voltage range.

[0100] S61. If the voltage of the DC power output by the DC battery 3 is outside the selected expected step-down voltage range, the current battery relay 31 is disconnected and the battery relay 31 corresponding to the DC transformer 32 which is closest to the current step-down range and greater than the current step-down range is closed.

[0101] S611 , if the current voltage reduction range is the maximum voltage reduction range, all battery relays 31 are disconnected and the emergency relay 33 is closed.

[0102] S7, comparing the current value output by the DC battery with the current warning value;

[0103] S71. If the current value exceeds the current warning value, a DC converter 32 corresponding to a preset step-down range that is closest to the preset step-down range and larger than the preset step-down range is selected for connection.

[0104] The embodiments of this specific implementation method are all preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Therefore, any equivalent changes made based on the structure, shape, and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A photovoltaic inverter power supply control system, characterized in that: The invention comprises a photovoltaic power generation component (2), a DC storage battery (3) electrically connected to the photovoltaic power generation component (2), a plurality of inverter power supply components (4) electrically connected to the DC storage battery (3), and a general control system (1), wherein the general control system (1) comprises a first voltage monitoring module (11), a voltage control module (12), a voltage adjustment module (121), a temperature detection module (13), a low temperature judgment module (131), a temperature early warning module (14), and a cycle start-stop module (15); The first voltage monitoring module (11) detects a first voltage value of the direct current output by the photovoltaic power generation component (2), and transmits the first voltage value to the voltage control module (12); The voltage control module (12) is preset with a preset voltage table, which includes a plurality of preset voltage ranges, voltage reduction level signals and expected voltage reduction voltage ranges, and the preset voltage ranges, voltage reduction level signals and expected voltage reduction voltage ranges are all in one-to-one correspondence. The voltage control module (12) compares the first voltage value according to the preset voltage table, selects the corresponding voltage reduction level signal and expected voltage reduction voltage range according to the preset voltage range in which the first voltage value is located, and transmits the voltage reduction level signal to the voltage adjustment module (121); The voltage adjustment module (121) comprises a plurality of battery relays (31) arranged between the photovoltaic power generation assembly (2) and the DC storage battery (3) and a DC transformer (32) connected in series to each battery relay (31); different DC transformers (32) have different voltage reduction ranges, and the voltage adjustment module (121) controls the opening and closing of the battery relay (31) according to the received voltage reduction level signal; The temperature detection module (13) detects the temperature value of each inverter power supply component (4), numbers the temperature value according to the inverter power supply component (4), and transmits the temperature value to the low temperature judgment module (131) and the temperature early warning module (14); The low temperature judgment module (131) is preset with a low temperature preset value, and the low temperature judgment module (131) compares the temperature value with the low temperature preset value. If all temperature values ​​are lower than the low temperature preset value, the voltage control module (12) is controlled to stop working and transmit a voltage reduction level signal of the highest voltage reduction range to the voltage adjustment module (121); The temperature warning module (14) is preset with a temperature warning value and a preset time, and the temperature warning module (14) compares the temperature value with the temperature warning value; when only one temperature value is higher than the temperature warning value, the inverter power supply component (4) corresponding to the number of the temperature value is controlled to stop working and stop receiving temperature values, and timing is performed at the same time; when the number of temperature values ​​higher than the temperature warning value is greater than or equal to two, a start signal and the number of the temperature value with the highest value are transmitted to the circulation start and stop module (15), and the temperature value is stopped from being received, and timing is performed at the same time; after the timing reaches the preset time, the temperature value is received again; The cyclic start-stop module (15) is preset with the sequence of the inverter power components (4) and the set time. After receiving the start signal and the number of the temperature value, the cyclic start-stop module (15) controls the inverter power component (4) corresponding to the number of the temperature value to stop working, and starts with the inverter power component (4) and controls the inverter power component (4) to stop working and start after the set time according to the sequence of the inverter power components (4).

2. A photovoltaic inverter power supply control system according to claim 1, characterized in that: The overall control system (1) also includes a second voltage monitoring module (111) and a fault processing module (122); The second voltage monitoring module (111) detects a second voltage value of the direct current output by the direct current storage battery (3), and transmits the second voltage value to the voltage control module (12); The voltage control module (12) compares the second voltage value with the expected step-down voltage range, and transmits a step-down fault signal to the fault processing module (122) if the second voltage value is outside the selected expected step-down voltage range; The voltage adjustment module (121) further comprises an emergency relay (33) arranged between the photovoltaic power generation assembly (2) and the DC storage battery (3); After receiving the voltage reduction fault signal, the fault processing module (122) controls the voltage control module (12) to stop working, the fault processing module (122) sends a fault alarm signal, and controls the voltage adjustment module (121) to disconnect the current battery relay (31) and close the battery relay (31) corresponding to the DC transformer (32) that is closest to the current voltage reduction range and greater than the current voltage reduction range; if the current voltage reduction range is the maximum voltage reduction range, all battery relays (31) are disconnected and the emergency relay (33) is closed.

3. A photovoltaic inverter power supply control system according to claim 1, characterized in that: The overall control system (1) further comprises a temperature alarm module (16); The temperature detection module (13) sends the numbered temperature value to the temperature alarm module (16); The temperature alarm module (16) is preset with a temperature alarm value. The temperature alarm module (16) compares the temperature value with the temperature alarm value. When only one temperature value is higher than the temperature alarm value, the temperature alarm module (16) transmits the number of the temperature value to the cycle start and stop module (15). When the number of temperature values ​​higher than the temperature alarm value is greater than or equal to two, the temperature alarm module (16) controls the inverter power supply components (4) corresponding to the numbers of all temperature values ​​higher than the temperature alarm value to stop working, and transmits the numbers of all temperature values ​​higher than the temperature alarm value to the cycle start and stop module (15). The temperature alarm module (16) sends a temperature alarm signal. When the cycle start-stop module (15) receives the number of the temperature value and the start signal, it locks the corresponding inverter power component (4) according to the number of the received temperature value, and skips the locked inverter power component (4) when controlling the inverter power component (4) according to the order of the inverter power component (4).

4. A photovoltaic inverter power supply control system according to claim 3, characterized in that: The overall control system (1) further comprises a current monitoring module (17) and a current early warning module (171); The current monitoring module (17) detects the current output by the DC battery (3) and transmits the current value to the current early warning module (171); The current warning module (171) is preset with a current warning value, and the current warning module (171) compares the current value with the current warning value, and transmits a current warning signal to the voltage adjustment module (121) when the current value exceeds the current warning value; After the voltage adjustment module (121) receives the voltage reduction level signal, if it also receives the current warning signal, it calls the preset voltage table of the voltage control module (12), queries the corresponding preset voltage range based on the currently received voltage reduction level signal and the preset voltage table, selects the preset voltage range that is closest to the queried preset voltage range and greater than the queried preset voltage range, and controls the corresponding battery relay (31) to close based on the selected preset voltage range.

5. A photovoltaic inverter power supply control system according to claim 3, characterized in that: A solar refrigerator (5) is arranged near the inverter power supply assembly (4), and the overall control system (1) further comprises a refrigeration control module (18); The refrigeration control module (18) is connected to the solar refrigerator (5) and receives a temperature alarm signal. After receiving the temperature alarm signal, the refrigeration control module (18) controls the solar refrigerator (5) to operate.

6. A photovoltaic inverter power supply control system according to claim 5, characterized in that: The refrigerant water pipeline of the solar refrigerator (5) is fixedly connected to a plurality of refrigeration pipelines (51), the number of the refrigeration pipelines (51) is the same as the number of the inverter power supply components (4), each refrigeration pipeline (51) is close to an inverter power supply component (4), and each refrigeration pipeline (51) is fixedly connected to a solenoid valve (52); The temperature alarm module (16) sends a temperature alarm signal and a temperature value number to the refrigeration control module (18); The refrigeration control module (18) is preset with a number correspondence table, which includes the number of the temperature value and the number of the solenoid valve (52). After the refrigeration control module (18) receives the temperature alarm signal and the number of the temperature value, it searches the number of the corresponding solenoid valve (52) in the number correspondence table according to the number of the temperature value, and the refrigeration control module (18) controls the solenoid valve (52) to open according to the searched number of the solenoid valve (52).

7. A photovoltaic inverter power supply control system according to claim 6, characterized in that: The refrigeration control module (18) controls the solenoid valve (52) to open and then locks the solenoid valve (52). When the solenoid valve (52) is locked, the refrigeration control module (18) does not close the locked solenoid valve (52). At the same time, the refrigeration control module (18) transmits the monitoring signal and the number of the received temperature value to the temperature warning module (14). After receiving the unlocking signal and the number of the temperature value, the refrigeration control module (18) unlocks the solenoid valve (52) corresponding to the number of the temperature value and closes the solenoid valve (52). When receiving the monitoring signal and the number of the temperature value, the temperature warning module (14) monitors the temperature value of the inverter power supply component (4) corresponding to the number of the temperature value, and transmits an unlocking signal and the number of the temperature value to the refrigeration control module (18) when the monitored temperature value is lower than the temperature warning value.

8. A photovoltaic inverter power supply control system according to claim 3, characterized in that: The system also includes a host terminal (6) and a mobile terminal (7). The overall control system (1) also includes a wireless communication module (19). The wireless communication module (19) receives a temperature alarm signal output by the temperature alarm module (16) and sends the temperature alarm signal to the host terminal (6) and the mobile terminal (7).

9. A photovoltaic inverter power supply control system according to claim 1, characterized in that: A cooling fan (8) is arranged near the inverter power supply component (4), and the temperature warning module (14) is connected to the cooling fan (8). When any temperature value in the comparison result of the temperature warning module (14) is higher than the temperature warning value, the temperature warning module (14) controls the cooling fan (8) to start.

10. A photovoltaic inverter power supply control method, using the photovoltaic inverter power supply control system according to any one of claims 1 to 9, characterized in that: The following steps are involved: Setting a preset voltage meter, a low temperature preset value, a temperature warning value, a preset time, an inverter power supply component (4) sequence and a set time; Monitoring a first voltage value of direct current output by a photovoltaic power generation assembly (2); Monitoring the temperature of each inverter power supply component (4); Determining a battery relay (31) that should be closed based on a preset voltage meter and a first voltage value of direct current output by a photovoltaic power generation assembly (2), and closing the battery relay (31); After the battery relay (31) is closed, the DC voltage conversion converter (32) connected in series with the battery relay (31) is connected to the front end circuit of the DC storage battery (3); Comparing the temperature value of the inverter power supply component (4) with the low temperature preset value and the temperature warning value; If all temperature values ​​are lower than the low temperature preset value, the battery relay (31) corresponding to the DC voltage conversion converter (32) in the highest voltage reduction range is closed, and the comparison of the first voltage value is stopped at the same time; If only one temperature value is higher than the temperature warning value, the inverter power supply component (4) corresponding to the number of the temperature value is controlled to stop working, and a comparison is performed again after a preset time. If the number of temperature values ​​higher than the temperature warning value is greater than or equal to two, the inverter power supply component (4) corresponding to the number of the temperature value with the highest numerical value is controlled to stop working for a set time, and the inverter power supply component (4) is controlled to start after stopping working for the set time according to the sequence of the inverter power supply components (4).

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