A load power supply control method and related device for a photovoltaic power generation system

Abstract

The present invention discloses a load power supply control method and related device for a photovoltaic power generation system. The method includes: the power supply control device obtains the current power generation power of a plurality of photovoltaic power generation components, the current load power at the load end, and the current remaining power of the energy storage battery pack; based on the current power generation power, the current load power, and the current remaining power, it determines whether to execute an off-grid mode or a grid-connected mode; when executing the off-grid mode, based on the current power generation power and the current remaining power, it performs inverter power supply control to the load end according to the current load power; when executing the grid-connected mode, based on the current power generation power and the grid end, it performs inverter power supply control to the load end according to the current load power; it monitors the commercial power at the grid end in real time, and when there is an abnormality in the commercial power at the grid end, it controls the switching from the current grid-connected mode to the off-grid mode. In the embodiments of the present invention, the off-grid and grid-connected control of the photovoltaic power generation system is realized, and stable power supply to the load end is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of power control, and in particular, to a load power supply control method and related device for a photovoltaic power generation system. Background Art

[0002] With the development of photovoltaic technology, more small photovoltaic power generation systems are now installed and used in households. At this time, they are basically installed and used off-grid. And when the power generation of the photovoltaic power generation system and the stored power of the energy storage battery cannot meet the load demand, the user needs to manually switch to the grid side and use the mains power of the grid side. In this way, the user needs to manually switch the power supply, and there may be certain safety hazards, and it also brings inconvenience to power use, resulting in a poor power use experience. Summary of the Invention

[0003] An object of the present invention is to overcome the deficiencies of the prior art. The present invention provides a load power supply control method and related device for a photovoltaic power generation system, which realizes off-grid and grid-connected control of the photovoltaic power generation system and realizes stable power supply at the load end.

[0004] To solve the above technical problems, an embodiment of the present invention provides a load power supply control method for a photovoltaic power generation system, which is applied to a photovoltaic power generation system. The photovoltaic power generation system includes a plurality of photovoltaic power generation components, an energy storage battery pack, a power supply control device, a load end, and a grid end. The method includes:

[0005] The power supply control device obtains the current power generation power of the plurality of photovoltaic power generation components, the current load power of the load end, and the current remaining power of the energy storage battery pack;

[0006] The power supply control device determines whether the photovoltaic power generation system executes an off-grid mode or a grid-connected mode based on the current power generation power, the current load power, and the current remaining power;

[0007] When the photovoltaic power generation system executes the off-grid mode, the power supply control device performs inverter power supply control on the load end according to the current load power based on the current power generation power and the current remaining power;

[0008] When the photovoltaic power generation system executes the grid-connected mode, the power supply control device performs inverter power supply control on the load end according to the current load power based on the current power generation power and the grid end. At the same time,

[0009] The power supply control device monitors the mains power of the grid end in real time, and when there is an abnormality in the mains power of the grid end, controls the switching from the current grid-connected mode to the off-grid mode.

[0010] Optionally, the power supply control device obtains the current power generation power of the plurality of photovoltaic power generation components, the current load power of the load end, and the current remaining power of the energy storage battery pack, including:

[0011] When the photovoltaic power generation system is started, the power supply control device controls the sensors at the corresponding nodes to perform data acquisition and processing, and obtains the current power generation power of the plurality of photovoltaic power generation components, the current load power of the load end, and the current remaining power of the energy storage battery pack.

[0012] Optionally, the power supply control device determines whether the photovoltaic power generation system executes an off-grid mode or a grid-connected mode based on the current power generation power, the current load power, and the current remaining power, including:

[0013] When the current power generation power is greater than or equal to the current load power and the current remaining power is less than a first preset power, or when the current power generation power is less than the current load power and the current remaining power is greater than a second preset power, the power supply control device determines that the photovoltaic power generation system executes the off-grid mode;

[0014] When the current power generation power is greater than or equal to the current load power and the current remaining power is greater than or equal to the first preset power, or when the current power generation power is less than the current load power and the current remaining power is less than or equal to the second preset power, the power supply control device determines that the photovoltaic power generation system executes the grid-connected mode; the first preset power is greater than the second preset power.

[0015] Optionally, when the photovoltaic power generation system executes the off-grid mode, the power supply control device performs inverter power supply control on the load end according to the current load power based on the current power generation power and the current remaining power, including:

[0016] When the photovoltaic power generation system executes the off-grid mode, the power supply control device compares whether the current power generation power is greater than or equal to the current load power;

[0017] When the current power generation power is greater than or equal to the current load power, the power supply control device controls the current power generation power to perform inverter power supply processing on the load end according to the load voltage and load frequency of the load end, and performs charging control on the energy storage battery pack based on the total amount consistent charge and discharge control strategy for the remaining power generation power;

[0018] When the current power generation is less than the current load power, the power supply control device controls the current power generation and the energy storage battery pack based on the current load power, and performs inverter power supply control to the load end according to the load voltage and load frequency at the load end with a total consistent charge and discharge control strategy.

[0019] Optionally, after the power supply control device controls the current power generation and the energy storage battery pack based on the current load power, and performs inverter power supply control to the load end according to the load voltage and load frequency at the load end with a total consistent charge and discharge control strategy, it further includes:

[0020] The power supply control device performs real-time monitoring and processing on the current remaining power of the energy storage battery pack, and when it monitors that the current remaining power is less than the second preset power, it switches the currently executed off-grid mode to the grid-connected mode.

[0021] Optionally, when the photovoltaic power generation system executes the grid-connected mode, the power supply control device performs inverter power supply control to the load end based on the current power generation and the grid side according to the current load power, including:

[0022] When the photovoltaic power generation system executes the grid-connected mode, the power supply control device compares whether the current power generation is greater than or equal to the current load power;

[0023] When the current power generation is greater than or equal to the current load power, the power supply control device controls the current power generation according to the current load power, performs inverter power supply control to the load end according to the load voltage and load frequency at the load end, and feeds back the remaining power generation to the grid side based on the grid-connected mode;

[0024] When the current power generation is less than the current load power, the power supply control device performs inverter control on the current power generation according to the load end voltage and load end frequency to form an inverter output power, and the power supply control device controls the inverter output power and the grid side in the grid-connected mode to perform coordinated power supply processing to the load end.

[0025] Optionally, the feeding back the remaining power generation to the grid side based on the grid-connected mode includes:

[0026] The power supply control device obtains the target parameters corresponding to the grid side, and the target parameters include the angular frequency value and voltage value of the grid side;

[0027] The power supply control device sets the oscillation angular frequency of the voltage-controlled oscillator of the phase-locked loop arranged on the feedback side in the grid-connected mode to the angular frequency value, and obtains the output phase fed back to the grid side;

[0028] Construct a virtual control model using the Lyapunov function based on the difference between the output phase and the voltage phase corresponding to the voltage value at the grid side, and generate a control signal based on the virtual control model;

[0029] The power supply control device adjusts the angular frequency value of the voltage-controlled oscillator of the phase-locked loop based on the control signal, and when the output phase is consistent with the voltage phase corresponding to the voltage value at the grid side, controls the remaining generated power to be fed back to the grid side based on the grid connection mode.

[0030] In addition, an embodiment of the present invention further provides a load power supply control device for a photovoltaic power generation system, which is applied to a photovoltaic power generation system. The photovoltaic power generation system includes a plurality of photovoltaic power generation components, an energy storage battery pack, a power supply control device, a load end, and a grid end; the device includes:

[0031] An acquisition module: used for the power supply control device to acquire the current generated power of the plurality of photovoltaic power generation components, the current load power of the load end, and the current remaining power of the energy storage battery pack;

[0032] A confirmation module: used for the power supply control device to confirm whether the photovoltaic power generation system executes an off-grid mode or a grid-connected mode based on the current generated power, the current load power, and the current remaining power;

[0033] An off-grid operation module: used for the power supply control device to perform inverter power supply control to the load end according to the current load power based on the current generated power and the current remaining power when the photovoltaic power generation system executes the off-grid mode;

[0034] A grid-connected operation module: used for the power supply control device to perform inverter power supply control to the load end according to the current load power based on the current generated power and the grid end when the photovoltaic power generation system executes the grid-connected mode; meanwhile,

[0035] A real-time monitoring module: used for the power supply control device to perform real-time monitoring on the commercial power at the grid end, and when there is an abnormality in the commercial power at the grid end, control the switching from the current grid-connected mode to the off-grid mode.

[0036] In addition, an embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored, and when the program is executed by a processor, it implements the load power supply control method described in any one of the above.

[0037] In addition, an embodiment of the present invention further provides a power supply control device, and the feedback control device includes:

[0038] One or more processors;

[0039] Memory;

[0040] One or more applications, wherein the one or more applications are stored in the memory and configured to be executed by the one or more processors, and the one or more applications are configured to: execute the load power supply control method according to any one of the above.

[0041] In the embodiment of the present invention, by obtaining the current power generation power, the current load power, and the current remaining power of the energy storage battery pack, then confirming to execute the off-grid mode or the grid-connected mode, and stably supplying power to the load end of the user side according to the executed mode; at the same time, switching the corresponding mode according to the specific operation situation in real time according to the demand; realizing the off-grid and grid-connected control of the photovoltaic power generation system and realizing the stable power supply of the load end. Description of the Drawings

[0042] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained according to these drawings without creative efforts.

[0043] Figure 1 It is a schematic flow chart of the load power supply control method of the photovoltaic power generation system in the embodiment of the present invention;

[0044] Figure 2 It is a schematic structural composition diagram of the load power supply control device of the photovoltaic power generation system in the embodiment of the present invention;

[0045] Figure 3 It is a schematic structural composition diagram of the power supply control device in the embodiment of the present invention. Detailed Embodiments

[0046] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0047] Embodiment 1, please refer to Figure 1 , Figure 1 It is a schematic flow chart of the load power supply control method of the photovoltaic power generation system in the embodiment of the present invention.

[0048] As Figure 1As shown, a load power supply control method for a photovoltaic power generation system is applied to a photovoltaic power generation system, which includes a plurality of photovoltaic power generation components, an energy storage battery pack, a power supply control device, a load end, and a power grid end; among them, the plurality of photovoltaic power generation components generate electricity in series, and the plurality of photovoltaic power generation components, the energy storage battery pack, the load end, and the power grid end are all connected to the power supply control device for control connection and power-on connection. An inverter device and a phase-locked loop are built in the power supply control device; the method includes:

[0049] S11: The power supply control device obtains the current power generation power of the plurality of photovoltaic power generation components, the current load power of the load end, and the current remaining power of the energy storage battery pack;

[0050] In the specific implementation process of the present invention, the power supply control device obtains the current power generation power of the plurality of photovoltaic power generation components, the current load power of the load end, and the current remaining power of the energy storage battery pack, including: when the photovoltaic power generation system is started, the power supply control device controls the sensors at the corresponding nodes to perform data acquisition and processing, and obtains the current power generation power of the plurality of photovoltaic power generation components, the current load power of the load end, and the current remaining power of the energy storage battery pack.

[0051] Specifically, first, corresponding sensors are provided on the load end, the energy storage battery pack, and the plurality of photovoltaic power generation components. After the photovoltaic power generation system is started, the power supply control device will control the corresponding sensors provided at the corresponding nodes to perform data acquisition and processing, and the current power generation power of the plurality of photovoltaic power generation components, the current load power of the load end, and the current remaining power of the energy storage battery pack can be obtained.

[0052] S12: The power supply control device determines whether the photovoltaic power generation system executes an off-grid mode or a grid-connected mode based on the current power generation power, the current load power, and the current remaining power;

[0053] In the specific implementation process of the present invention, the power supply control device determines whether the photovoltaic power generation system executes an off-grid mode or a grid-connected mode based on the current power generation power, the current load power, and the current remaining power, including:

[0054] When the current power generation is greater than or equal to the current load power and the current remaining power is less than a first preset power, or when the current power generation is less than the current load power and the current remaining power is greater than a second preset power, the power supply control device confirms that the photovoltaic power generation system executes the off-grid mode; when the current power generation is greater than or equal to the current load power and the current remaining power is greater than or equal to the first preset power, or when the current power generation is less than the current load power and the current remaining power is less than or equal to the second preset power, the power supply control device confirms that the photovoltaic power generation system executes the grid-connected mode; the first preset power is greater than the second preset power.

[0055] Specifically, the power supply control device needs to confirm whether the photovoltaic power generation system executes the off-grid mode or the grid-connected mode according to the current power generation, the current load power, and the current remaining power; first, it is necessary to judge whether the current power generation is greater than or equal to the current load power, and whether the current remaining power is less than the first preset power and greater than the second preset power; that is, when the current power generation is greater than or equal to the current load power and the current remaining power is less than the first preset power, at this time, the power generated by several photovoltaic modules meets the load demand of the load terminal, and the remaining power of the energy storage battery pack is less than the set first preset power. The remaining power generation after the power generated by several photovoltaic modules meets the load demand of the load terminal is used to charge the energy storage battery pack; or when the current power generation is less than the current load power and the current remaining power is greater than the second preset power, that is, when the power generated by several photovoltaic modules cannot meet the load demand of the load terminal, but the remaining power of the energy storage battery is at the set second preset power, the power in the energy storage battery pack can be used to supplement the power supply to the load terminal; that is, in these two cases, the grid side does not need to participate, and the off-grid mode can be executed.

[0056] When the current power generation is greater than or equal to the current load power and the current remaining power is greater than or equal to the first preset power, it can be understood that after the power generated by several photovoltaic modules meets the power consumption required by the load end, there is still surplus power. At this time, the remaining power in the energy storage battery pack reaches the set first preset power, that is, the current energy storage battery pack can be understood as being fully charged and does not need to be charged. However, at this time, the surplus power generation can be fed back to the grid end, and the grid connection mode needs to be executed at this time; or, when the current power generation is less than the current load power and the current remaining power is less than or equal to the second preset power, it can be understood that the power generated by several photovoltaic modules cannot meet the power consumption demand of the load end, and the energy storage battery pack has no power left. In order to meet the power consumption demand of the load end, power needs to be supplemented by the grid end, that is, the grid connection mode also needs to be executed; the power lower than the preset power and greater than the second preset power can be understood as the first preset power being the maximum capacity that the energy storage battery pack can reach when charging; the second preset power is the lowest capacity that the energy storage battery pack can reach when discharging; that is, it can be understood that when the first preset power is reached, the energy storage battery pack is in a fully charged state, and when the second preset power is reached, the energy storage battery pack is in a powerless state.

[0057] S13: When the photovoltaic power generation system executes the off-grid mode, the power supply control device performs inverter power supply control on the load end according to the current load power based on the current power generation and the current remaining power.

[0058] In the specific implementation process of the present invention, when the photovoltaic power generation system executes the off-grid mode, the power supply control device performs inverter power supply control on the load end according to the current load power based on the current power generation and the current remaining power, including: when the photovoltaic power generation system executes the off-grid mode, the power supply control device compares whether the current power generation is greater than or equal to the current load power; when the current power generation is greater than or equal to the current load power, the power supply control device controls the current power generation according to the current load power to perform inverter power supply processing on the load end according to the load voltage and load frequency of the load end, and performs charging control on the energy storage battery pack for the remaining power generation based on the total amount consistent charge and discharge control strategy; when the current power generation is less than the current load power, the power supply control device controls the current power generation and the energy storage battery pack based on the current load power to perform inverter power supply control on the load end according to the load voltage and load frequency of the load end according to the total amount consistent charge and discharge control strategy.

[0059] Further, after the power supply control device controls the current power generation power and the energy storage battery pack based on the current load power and performs inverter power supply control on the load end according to the load voltage and load frequency at the load end in accordance with the total amount consistent charge and discharge control strategy, it further includes: the power supply control device monitors and processes the current remaining power of the energy storage battery pack in real time, and when it monitors that the current remaining power is less than the second preset power, it switches the currently executed off-grid mode to the grid-connected mode.

[0060] Specifically, when the photovoltaic power generation system executes the off-grid mode, it is necessary for the power supply control device to compare whether the current power generation power is greater than or equal to the current load power; and when the current power generation power is greater than or equal to the current load power, at this time, the power supply control device will control the current power generation power according to the current load power and perform inverter power supply processing on the load end according to the load voltage and load frequency at the load end, that is, first boost the power generated by several photovoltaic modules to 220V, and then invert the 220V DC power into 220V AC power through an inverter and supply it to the load end; at the same time, use the remaining power generation power to control the charging of the energy storage battery pack; in this technical solution, the total amount consistent charge and discharge control vehicle is adopted to perform charging control on the energy storage battery pack; that is, according to the remaining generated current corresponding to the remaining generated power, the remaining generated current is allocated according to the optimal charging current of each energy storage battery pack, so that the sum of the charging currents of each energy storage battery pack is equal to the remaining generated current.

[0061] When the current power generation power is less than the current load power, at this time, it is necessary for the energy storage battery pack to perform auxiliary power supply. At this time, the power supply control device will control the current power generation power and the energy storage battery pack according to the current load power and perform inverter power supply control on the load end according to the load voltage and load frequency at the load end; that is, after using the current power generation power to supply power to the load end, the remaining power demand will be supplemented by the energy storage battery pack. At this time, it is necessary to obtain the required supplementary power, calculate the discharge current of the energy storage battery pack when performing power supplementation according to the supplementary power, and then distribute the discharge circuit to each energy storage battery pack in the manner of the total amount consistent charge and discharge control strategy, so as to effectively ensure the safe operation of the energy storage battery pack and improve the service life of the energy storage battery pack.

[0062] Since it is necessary for the energy storage battery pack to perform supplementary power supply, it is necessary to monitor the remaining power of the energy storage battery pack in real time. When it is monitored that the current remaining power is less than the second preset power, that is, after the energy storage battery pack runs out of power, in order to ensure the power safety and power experience of the load end, it is necessary to switch the off-grid mode to the grid-connected mode at this time and supplement the power supply to the load end through the grid side.

[0063] S14: When the photovoltaic power generation system operates in the grid-connected mode, the power supply control device performs inverter power supply control on the load side based on the current power generation power and the grid side according to the current load power;

[0064] In the specific implementation process of the present invention, when the photovoltaic power generation system operates in the grid-connected mode, the power supply control device performs inverter power supply control on the load side based on the current power generation power and the grid side according to the current load power, including:

[0065] When the photovoltaic power generation system operates in the grid-connected mode, the power supply control device compares whether the current power generation power is greater than or equal to the current load power; when the current power generation power is greater than or equal to the current load power, the power supply control device controls the current power generation power to perform inverter power supply control on the load side according to the load voltage and load frequency of the load side, and feeds back the remaining power generation power to the grid side based on the grid-connected mode; when the current power generation power is less than the current load power, the power supply control device performs inverter control on the current power generation power according to the load side voltage and load side frequency to form an inverter output power, and the power supply control device performs coordinated power supply processing on the inverter output power and the grid side in the grid-connected mode to the load side.

[0066] Further, feeding back the remaining power generation power to the grid side based on the grid-connected mode includes: the power supply control device obtains the target parameters corresponding to the grid side, and the target parameters include the angular frequency value and voltage value of the grid side; the power supply control device sets the oscillation angular frequency of the voltage-controlled oscillator of the phase-locked loop arranged on the feedback side in the grid-connected mode to the angular frequency value, and obtains the output phase fed back to the grid side; constructs a virtual control model by using the Lyapunov function based on the difference between the output phase and the voltage phase corresponding to the voltage value of the grid side, and generates a control signal based on the virtual control model; the power supply control device adjusts the angular frequency value of the voltage-controlled oscillator of the phase-locked loop based on the control signal, and when the output phase is consistent with the voltage phase corresponding to the voltage value of the grid side, controls to feed back the remaining power generation power to the grid side based on the grid-connected mode.

[0067] Specifically, when the photovoltaic power generation system operates in the grid-connected mode, the power supply control device first needs to compare whether the current power generation power is greater than or equal to the current load power; and when the current power generation power is greater than or equal to the current load power, the power supply control device will control the current power generation power according to the current load power to perform inverter power supply control to the load end according to the load voltage and load frequency at the load end, and feed back the remaining power generation power to the grid end according to the grid-connected mode; or when the current power generation power is less than the current load power, the power supply control device performs inverter control on the current power generation power according to the load voltage and load frequency at the load end to form an inverter output power, and the power supply control device will control the inverter output power and the grid end in the grid-connected mode to perform coordinated power supply processing to the load end; that is, in the grid-connected mode, there are two situations. One is that the photovoltaic power generation system feeds back electric energy to the grid end, and the other is that the grid end needs to supplement the supply of electric energy.

[0068] When it is necessary to feed back electric energy to the grid end, in order to ensure the safe operation of the grid end, at this time, the power supply control device first needs to obtain the corresponding target parameters of the grid end, that is, the target parameters include the angular frequency value and voltage value of the grid end; at this time, it is necessary for the power supply control device to set the oscillation angular frequency of the voltage-controlled oscillator of the phase-locked loop arranged on the feedback side in the grid-connected mode to this angular frequency value, and then obtain the output phase fed back to this grid end; then make a difference between the output phase and the voltage phase corresponding to the voltage value of the grid end, and judge whether the difference is within the preset range. If it is within the preset range, the remaining power generation power can be fed back to the grid end with this output phase; if the difference exceeds the preset range, corresponding control correction is required, that is, a virtual control model is constructed by using the Lyapunov function, and a control signal is generated through the virtual control model; then the power supply control device will adjust the angular frequency value of the voltage-controlled oscillator of the phase-locked loop according to the control signal, and when the output phase is consistent with the voltage phase corresponding to the voltage value of the grid end, control the remaining power generation power to be fed back to the grid end through the grid-connected mode, so that the stable and safe operation of the grid end can be effectively guaranteed when feeding back electric energy to the grid end in the grid-connected mode.

[0069] S15: The power supply control device monitors the commercial power of the grid end in real time, and when the commercial power of the grid end is abnormal, controls the switch from the current grid-connected mode to the off-grid mode.

[0070] In the specific implementation process of the present invention, in the grid-connected mode, in order to ensure the safe operation of the grid end, when there is a power outage at the grid end, it is necessary to promptly switch the grid-connected mode to the off-grid mode, that is, it is necessary for the power supply control device to monitor the commercial power of the grid end in real time, and when the commercial power of the grid end is abnormal, control the switch from the current grid-connected mode to the off-grid mode.

[0071] In an embodiment of the present invention, by obtaining the current power generation, the current load power, and the current remaining power of the energy storage battery pack, then confirming to execute the off-grid mode or the grid-connected mode, and stably supplying power to the load end of the user side according to the executed mode; at the same time, switching the corresponding mode in real time according to the specific operation conditions as required; realizing the off-grid and grid-connected control of the photovoltaic power generation system and realizing the stable power supply of the load end.

[0072] Embodiment 2. Please refer to Figure 2 , Figure 2 which is a schematic structural composition diagram of a load power supply control device of a photovoltaic power generation system in an embodiment of the present invention.

[0073] As Figure 2 shown, a load power supply control device of a photovoltaic power generation system is applied to a photovoltaic power generation system. The photovoltaic power generation system includes a plurality of photovoltaic power generation components, an energy storage battery pack, a power supply control device, a load end, and a grid end; wherein, the plurality of photovoltaic power generation components generate power in a series mode, and the plurality of photovoltaic power generation components, the energy storage battery pack, the load end, and the grid end are all connected to the power supply control device for control and power connection. An inverter device and a phase-locked loop are built in the power supply control device; the device includes:

[0074] An obtaining module 21: configured to obtain, by the power supply control device, the current power generation of the plurality of photovoltaic power generation components, the current load power of the load end, and the current remaining power of the energy storage battery pack;

[0075] In the specific implementation process of the present invention, the power supply control device obtains the current power generation of the plurality of photovoltaic power generation components, the current load power of the load end, and the current remaining power of the energy storage battery pack, including: when the photovoltaic power generation system is started, the power supply control device controls the sensors at the corresponding nodes to perform data acquisition and processing, and obtains the current power generation of the plurality of photovoltaic power generation components, the current load power of the load end, and the current remaining power of the energy storage battery pack.

[0076] Specifically, first, corresponding sensors are respectively arranged on the load end, the energy storage battery pack, and the plurality of photovoltaic power generation components. After the photovoltaic power generation system is started, the power supply control device will control the corresponding sensors arranged at the corresponding nodes to perform data acquisition and processing, and can obtain the current power generation of the plurality of photovoltaic power generation components, the current load power of the load end, and the current remaining power of the energy storage battery pack.

[0077] A confirmation module 22: configured to confirm, by the power supply control device, whether the photovoltaic power generation system executes the off-grid mode or the grid-connected mode based on the current power generation, the current load power, and the current remaining power;

[0078] In the specific implementation process of the present invention, the power supply control device determines whether the photovoltaic power generation system operates in an off-grid mode or a grid-connected mode based on the current power generation power, the current load power, and the current remaining power, including:

[0079] When the current power generation power is greater than or equal to the current load power and the current remaining power is less than a first preset power, or when the current power generation power is less than the current load power and the current remaining power is greater than a second preset power, the power supply control device determines that the photovoltaic power generation system operates in the off-grid mode; when the current power generation power is greater than or equal to the current load power and the current remaining power is greater than or equal to the first preset power, or when the current power generation power is less than the current load power and the current remaining power is less than or equal to the second preset power, the power supply control device determines that the photovoltaic power generation system operates in the grid-connected mode; the first preset power is greater than the second preset power.

[0080] Specifically, the power supply control device needs to determine whether the photovoltaic power generation system operates in the off-grid mode or the grid-connected mode according to the current power generation power, the current load power, and the current remaining power; first, it is necessary to determine whether the current power generation power is greater than or equal to the current load power, and whether the current remaining power is less than the first preset power and greater than the second preset power; that is, when the current power generation power is greater than or equal to the current load power and the current remaining power is less than the first preset power, at this time, the power generated by several photovoltaic modules meets the load demand at the load end, and the remaining power of the energy storage battery pack is less than the set first preset power. After the power generated by several photovoltaic modules meets the load demand at the load end, the remaining power generation is used to charge the energy storage battery pack; or when the current power generation power is less than the current load power and the current remaining power is greater than the second preset power, that is, when the power generated by several photovoltaic modules cannot meet the load demand at the load end, but the remaining power of the energy storage battery is at the set second preset power, the power in the energy storage battery pack can be used to supplement the power supply at the load end; that is, in these two cases, without the participation of the grid side, the off-grid mode can be executed.

[0081] When the current power generation is greater than or equal to the current load power and the current remaining power is greater than or equal to the first preset power, it can be understood that after the power generated by several photovoltaic modules meets the power consumption required by the load terminal, there is still surplus power. However, at this time, the remaining power in the energy storage battery pack reaches the set first preset power, that is, the current energy storage battery pack can be understood as being fully charged and does not need to be charged. However, at this time, the surplus power generation can be fed back to the grid side, and at this time, the grid connection mode needs to be executed; or, when the current power generation is less than the current load power and the current remaining power is less than or equal to the second preset power, it can be understood that the power generated by several photovoltaic modules cannot meet the power consumption demand of the load terminal, and the energy storage battery pack has no power left. In order to meet the power consumption demand of the load terminal, power needs to be supplemented from the grid side, that is, the grid connection mode also needs to be executed; the power lower than the preset power and greater than the second preset power can be understood that the first preset power is the maximum capacity that the energy storage battery pack can reach when charging; the second preset power is the minimum capacity that the energy storage battery pack can reach when discharging; that is, it can be understood that when reaching the first preset power, the energy storage battery pack is in a fully charged state, and when reaching the second preset power, the energy storage battery pack is in a powerless state.

[0082] Off-grid operation module 23: When the photovoltaic power generation system executes the off-grid mode, the power supply control device performs inverter power supply control on the load terminal according to the current load power based on the current power generation and the current remaining power.

[0083] In the specific implementation process of the present invention, when the photovoltaic power generation system executes the off-grid mode, the power supply control device performs inverter power supply control on the load terminal according to the current load power based on the current power generation and the current remaining power, including: when the photovoltaic power generation system executes the off-grid mode, the power supply control device compares whether the current power generation is greater than or equal to the current load power; when the current power generation is greater than or equal to the current load power, the power supply control device controls the current power generation to perform inverter power supply processing on the load terminal according to the load voltage and load frequency of the load terminal based on the current load power, and performs charging control on the energy storage battery pack for the remaining power generation based on the total amount consistent charge and discharge control strategy; when the current power generation is less than the current load power, the power supply control device controls the current power generation and the energy storage battery pack to perform inverter power supply control on the load terminal according to the load voltage and load frequency of the load terminal based on the total amount consistent charge and discharge control strategy according to the current load power.

[0084] Further, after the power supply control device controls the current power generation power and the energy storage battery pack based on the current load power and performs inverter power supply control to the load end according to the load voltage and load frequency at the load end with a total amount consistent charge and discharge control strategy, it further includes: the power supply control device monitors and processes the current remaining power of the energy storage battery pack in real time, and when it monitors that the current remaining power is less than the second preset power, it switches the currently executed off-grid mode to the grid-connected mode.

[0085] Specifically, when the photovoltaic power generation system executes the off-grid mode, it is necessary for the power supply control device to compare whether the current power generation power is greater than or equal to the current load power; and when the current power generation power is greater than or equal to the current load power, at this time, the power supply control device will control the current power generation power according to the current load power and perform inverter power supply processing to the load end according to the load voltage and load frequency at the load end, that is, first boost the power generated by several photovoltaic modules to 220V, and then invert the 220V direct current into 220V alternating current through an inverter and supply it to the load end; at the same time, use the remaining power generation power for charging control of the energy storage battery pack; in this technical solution, a total amount consistent charge and discharge control strategy is adopted to control the vehicle to charge the energy storage battery pack; that is, according to the remaining generated current corresponding to the remaining power generation power, the remaining generated current is distributed according to the optimal charging current of each energy storage battery pack, so that the sum of the charging currents of each energy storage battery pack is equal to the remaining generated current.

[0086] When the current power generation power is less than the current load power, at this time, it is necessary for the energy storage battery pack to perform auxiliary power supply. At this time, the power supply control device will control the current power generation power and the energy storage battery pack according to the current load power and perform inverter power supply control to the load end according to the load voltage and load frequency at the load end; that is, after supplying power to the load end with the current power generation power, the remaining power demand will be supplemented by the energy storage battery pack. At this time, it is necessary to obtain the supplementary power required for supplementation, calculate the discharge current of the energy storage battery pack when performing power supplementation according to the supplementary power, and then distribute the discharge circuit to each energy storage battery pack in the way of the total amount consistent charge and discharge control strategy, so as to effectively ensure the operation safety of the energy storage battery pack and improve the service life of the energy storage battery pack.

[0087] Since it is necessary for the energy storage battery pack to perform supplementary power supply, it is necessary to monitor the remaining power of the energy storage battery pack in real time. When it is monitored that the current remaining power is less than the second preset power, that is, after the energy storage battery pack runs out of power, in order to ensure the power safety and power experience of the load end, it is necessary to switch the off-grid mode to the grid-connected mode at this time and supplement the power supply to the load end through the grid side.

[0088] Grid-connected operation module 24: When the photovoltaic power generation system executes the grid-connected mode, the power supply control device performs inverter power supply control on the load side based on the current power generation power and the grid side according to the current load power;

[0089] In the specific implementation process of the present invention, when the photovoltaic power generation system executes the grid-connected mode, the power supply control device performs inverter power supply control on the load side based on the current power generation power and the grid side according to the current load power, including:

[0090] When the photovoltaic power generation system executes the grid-connected mode, the power supply control device compares whether the current power generation power is greater than or equal to the current load power; when the current power generation power is greater than or equal to the current load power, the power supply control device controls the current power generation power according to the current load power to perform inverter power supply control on the load side according to the load voltage and load frequency of the load side, and feeds back the remaining power generation power to the grid side based on the grid-connected mode; when the current power generation power is less than the current load power, the power supply control device performs inverter control on the current power generation power according to the load side voltage and load side frequency to form an inverter output power, and the power supply control device performs coordinated power supply processing on the inverter output power and the grid side in the grid-connected mode to the load side.

[0091] Further, feeding back the remaining power generation power to the grid side based on the grid-connected mode includes: the power supply control device obtains the target parameters corresponding to the grid side, and the target parameters include the angular frequency value and voltage value of the grid side; the power supply control device sets the oscillation angular frequency of the voltage-controlled oscillator of the phase-locked loop arranged on the feedback side in the grid-connected mode to the angular frequency value, and obtains the output phase fed back to the grid side; constructs a virtual control model using the Lyapunov function based on the difference between the output phase and the voltage phase corresponding to the voltage value of the grid side, and generates a control signal based on the virtual control model; the power supply control device adjusts the angular frequency value of the voltage-controlled oscillator of the phase-locked loop based on the control signal, and when the output phase is consistent with the voltage phase corresponding to the voltage value of the grid side, controls to feed back the remaining power generation power to the grid side based on the grid-connected mode.

[0092] Specifically, when the photovoltaic power generation system operates in the grid-connected mode, the power supply control device first needs to compare whether the current power generation power is greater than or equal to the current load power; and when the current power generation power is greater than or equal to the current load power, the power supply control device will control the current power generation power according to the current load power to perform inverter power supply control to the load end according to the load voltage and load frequency at the load end, and feed back the remaining power generation power to the grid end according to the grid-connected mode; or when the current power generation power is less than the current load power, the power supply control device performs inverter control on the current power generation power according to the load voltage and load frequency at the load end to form an inverter output power, and the power supply control device will control the inverter output power and the grid end in the grid-connected mode to perform coordinated power supply processing to the load end; that is, in the grid-connected mode, there are two situations. One is that the photovoltaic power generation system feeds back electric energy to the grid end, and the other is that the grid end needs to supply supplementary electric energy.

[0093] When it is necessary to feed back electric energy to the grid end, in order to ensure the safe operation of the grid end, at this time, the power supply control device first needs to obtain the corresponding target parameters of the grid end, that is, the target parameters include the angular frequency value and voltage value of the grid end; at this time, it is necessary for the power supply control device to set the oscillation angular frequency of the voltage-controlled oscillator of the phase-locked loop arranged on the feedback side in the grid-connected mode to this angular frequency value, and then obtain the output phase fed back to this grid end; then make a difference between the output phase and the voltage phase corresponding to the voltage value of the grid end, and judge whether this difference is within the preset range. If it is within the preset range, the remaining power generation power can be fed back to the grid end with this output phase; if the difference exceeds the preset range, corresponding control correction is required, that is, a virtual control model is constructed by using the Lyapunov function, and a control signal is generated through the virtual control model; then the power supply control device will adjust the angular frequency value of the voltage-controlled oscillator of the phase-locked loop according to the control signal, and when the output phase is consistent with the voltage phase corresponding to the voltage value of the grid end, control the remaining power generation power to be fed back to the grid end through the grid-connected mode, so as to effectively ensure the stable and safe operation of the grid end when feeding back electric energy to the grid end in the grid-connected mode.

[0094] Real-time monitoring module 25: It is used for the power supply control device to perform real-time monitoring on the commercial power of the grid end, and when there is an abnormality in the commercial power of the grid end, control the switching from the current grid-connected mode to the off-grid mode.

[0095] In the specific implementation process of the present invention, in the grid-connected mode, in order to ensure the safe operation of the grid end, when there is a power outage at the grid end, it is necessary to promptly switch the grid-connected mode to the off-grid mode, that is, it is necessary for the power supply control device to perform real-time monitoring on the commercial power of the grid end, and when there is an abnormality in the commercial power of the grid end, control the switching from the current grid-connected mode to the off-grid mode.

[0096] In an embodiment of the present invention, by obtaining the current power generation power, the current load power, and the current remaining power of the energy storage battery pack, then confirming to execute the off-grid mode or the grid-connected mode, and stably supplying power to the load end of the user side according to the executed mode; at the same time, switching the corresponding mode in real time according to the specific operation conditions as required; realizing the off-grid and grid-connected control of the photovoltaic power generation system and realizing the stable power supply of the load end.

[0097] A computer-readable storage medium provided by an embodiment of the present invention, on which a computer program is stored, and when the program is executed by a processor, it implements the load power supply control method of any one of the above embodiments. Among them, the computer-readable storage medium includes, but is not limited to, any type of disk (including floppy disk, hard disk, optical disk, CD-ROM, and magneto-optical disk), ROM (Read-Only Memory), RAM (Random Access Memory), EPROM (Erasable Programmable Read-Only Memory), EEPROM (Electrically Erasable Programmable Read-Only Memory), flash memory, magnetic card or optical card. That is, the storage device includes any medium that can store or transmit information in a readable form by a device (such as a computer, mobile phone), and can be a read-only memory, a magnetic disk or an optical disk, etc.

[0098] An embodiment of the present invention also provides a computer application program, which runs on a computer, and the computer application program is used to execute the load power supply control method of any one of the above.

[0099] In addition, Figure 3 is a schematic structural diagram of the power supply control device in an embodiment of the present invention.

[0100] An embodiment of the present invention also provides a power supply control device, as Figure 3 shown. The power supply control device includes devices such as a processor 302, a memory 303, an input unit 304, and a display unit 305. Those skilled in the art can understand, Figure 3The structural components of the power supply control device shown do not constitute a limitation on all devices, and may include more or fewer components than shown, or combine certain components. The memory 303 can be used to store the application program 301 and each functional module. The processor 302 runs the application program 301 stored in the memory 303, thereby executing various functional applications and data processing of the device. The memory can be an internal memory or an external memory, or include both an internal memory and an external memory. The internal memory can include a read-only memory (ROM), a programmable ROM (PROM), an electrically programmable ROM (EPROM), an electrically erasable programmable ROM (EEPROM), a flash memory, or a random access memory. The external memory can include a hard disk, a floppy disk, a ZIP disk, a USB flash drive, a magnetic tape, etc. The memory disclosed in the present invention includes but is not limited to these types of memories. The memory disclosed in the present invention is only an example and not a limitation.

[0101] The input unit 304 is used to receive the input of signals and receive the keywords input by the user. The input unit 304 can include a touch panel and other input devices. The touch panel can collect the touch operations of the user on or near it (such as the operations of the user using a finger, a stylus, or any suitable object or accessory on or near the touch panel), and drive the corresponding connection device according to a pre-set program; the other input devices can include but are not limited to one or more of a physical keyboard, function keys (such as play control keys, switch keys, etc.), a trackball, a mouse, a joystick, etc. The display unit 305 can be used to display the information input by the user or the information provided to the user and various menus of the terminal device. The display unit 305 can be in the form of a liquid crystal display, an organic light-emitting diode, etc. The processor 302 is the control center of the terminal device, connecting various parts of the entire device through various interfaces and lines, and executing various functions and processing data by running or executing the software programs and / or modules stored in the memory 303, and calling the data stored in the memory.

[0102] As an embodiment, the power supply control device includes: one or more processors 302, a memory 303, one or more application programs 301, wherein the one or more application programs 301 are stored in the memory 303 and are configured to be executed by the one or more processors 302, and the one or more application programs 301 are configured to execute the load power supply control method in any one of the above embodiments.

[0103] In the embodiment of the present invention, by obtaining the current power generation, the current load power, and the current remaining power of the energy storage battery pack, then confirming to execute the off-grid mode or the grid-connected mode, and stably supplying power to the load end of the user side according to the executed mode; at the same time, switching the corresponding mode according to the demand in real time according to the specific operation conditions; realizing the off-grid and grid-connected control of the photovoltaic power generation system and realizing the stable power supply of the load end.

[0104] In addition, the above has introduced in detail a load power supply control method and related device for a photovoltaic power generation system provided by the embodiment of the present invention. In this article, specific examples have been used to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A load power supply control method for a photovoltaic power generation system, characterized in that: Applied to a photovoltaic power generation system, the photovoltaic power generation system includes a number of photovoltaic power generation components, an energy storage battery group, a power supply control device, a load end and a power grid end; the method includes: The power supply control device obtains the current power generation of the plurality of photovoltaic power generation components, the current load power of the load end, and the current remaining power of the energy storage battery group; The power supply control device confirms that the photovoltaic power generation system executes an off-grid mode or a grid-connected mode based on the current generated power, the current load power and the current remaining power; When the photovoltaic power generation system executes the off-grid mode, the power supply control device performs inverter power supply control to the load end according to the current load power based on the current power generation power and the current remaining power, including: The power supply control device compares whether the current power generation is greater than or equal to the current load power; When the current generated power is greater than or equal to the current load power, the power supply control device controls the current generated power based on the current load power to perform inverter power supply processing to the load end according to the load voltage and load frequency of the load end, and performs charging control on the energy storage battery group based on the total consistent charging and discharging control strategy for the remaining generated power; When the current power generation is less than the current load power, the power supply control device controls the current power generation and the energy storage battery pack based on the current load power to perform inverter power supply control to the load end according to the load voltage and load frequency of the load end with a total amount consistent charge and discharge control strategy; When the photovoltaic power generation system is in grid-connected mode, the power supply control device performs inverter power supply control to the load end based on the current power generation power and the current load power of the grid end; at the same time, The power supply control device monitors the mains power at the power grid end in real time, and controls the current grid-connected mode to be switched to the off-grid mode when there is an abnormality in the mains power at the power grid end.

2. The load power supply control method according to claim 1, characterized in that: The power supply control device obtains the current power generation of the plurality of photovoltaic power generation components, the current load power of the load end, and the current remaining power of the energy storage battery group, including: When the photovoltaic power generation system is started, the power supply control device controls the sensors of the corresponding nodes to perform data acquisition processing to obtain the current power generation power of the photovoltaic power generation components, the current load power of the load end, and the current remaining power of the energy storage battery group.

3. The load power supply control method according to claim 1, characterized in that: The power supply control device confirms that the photovoltaic power generation system executes an off-grid mode or a grid-connected mode based on the current power generation power, the current load power, and the current remaining power, including: When the current generated power is greater than or equal to the current load power and the current remaining power is less than a first preset power, or when the current generated power is less than the current load power and the current remaining power is greater than a second preset power, the power supply control device confirms that the photovoltaic power generation system executes the off-grid mode; When the current power generation power is greater than or equal to the current load power and the current remaining power is greater than or equal to the first preset power, or when the current power generation power is less than the current load power and the current remaining power is less than or equal to the second preset power, the power supply control device confirms that the photovoltaic power generation system executes the grid-connected mode; the first preset power is greater than the second preset power.

4. The load power supply control method according to claim 1, characterized in that: After the power supply control device controls the current power generation power and the energy storage battery group to perform inverter power supply control to the load end according to the load voltage and load frequency of the load end in accordance with the total amount consistent charge and discharge control strategy based on the current load power, it also includes: The power supply control device monitors the current remaining power of the energy storage battery group in real time, and switches the currently executed off-grid mode to the on-grid mode when it is monitored that the current remaining power is less than a second preset power.

5. The load power supply control method according to claim 1, characterized in that: When the photovoltaic power generation system executes the grid-connected mode, the power supply control device performs inverter power supply control to the load end based on the current power generation power and the current load power of the grid end, including: When the photovoltaic power generation system executes the grid-connected mode, the power supply control device compares whether the current power generation power is greater than or equal to the current load power; When the current generated power is greater than or equal to the current load power, the power supply control device controls the current generated power according to the current load power, performs inverter power supply control to the load end according to the load voltage and load frequency of the load end, and feeds back the remaining generated power to the grid end based on the grid-connected mode; When the current generated power is less than the current load power, the power supply control device performs inverter control on the current generated power according to the load end voltage and the load end frequency to form an inverter output power. The power supply control device controls the inverter output power based on the current load power and performs coordinated power supply processing from the grid end in the grid-connected mode to the load end.

6. The load power supply control method according to claim 5, characterized in that: Feeding back the surplus generated power to the grid end based on the grid-connected mode includes: The power supply control device obtains target parameters corresponding to the power grid end, wherein the target parameters include an angular frequency value and a voltage value of the power grid end; The power supply control device sets the vibration angular frequency of the voltage-controlled oscillator of the phase-locked loop arranged on the feedback side of the grid-connected mode to the angular frequency value, and obtains the output phase fed back to the grid end; Building a virtual control model using a Lyapunov function based on a difference between an output phase and a voltage phase corresponding to a voltage value at the grid end, and generating a control signal based on the virtual control model; The power supply control device adjusts the angular frequency value of the voltage-controlled oscillator of the phase-locked loop based on the control signal, and when the output phase is consistent with the voltage phase corresponding to the voltage value of the grid end, controls the remaining generated power to be fed back to the grid end based on the grid-connected mode.

7. A load power supply control device for a photovoltaic power generation system, characterized in that: Applied to a photovoltaic power generation system, the photovoltaic power generation system includes a plurality of photovoltaic power generation components, an energy storage battery group, a power supply control device, a load end and a grid end; used to execute the load power supply control method according to any one of claims 1 to 6, the device includes: Acquisition module: used for the power supply control device to obtain the current power generation of the plurality of photovoltaic power generation components, the current load power of the load end, and the current remaining power of the energy storage battery group; Confirmation module: used for the power supply control device to confirm that the photovoltaic power generation system executes the off-grid mode or the grid-connected mode based on the current power generation power, the current load power and the current remaining power; Off-grid operation module: used for, when the photovoltaic power generation system is in off-grid mode, the power supply control device performs inverter power supply control to the load end according to the current load power based on the current power generation power and the current remaining power; Grid-connected operation module: used for, when the photovoltaic power generation system executes the grid-connected mode, the power supply control device performs inverter power supply control to the load end based on the current power generation power and the current load power of the grid end; at the same time, Real-time monitoring module: used for the power supply control device to monitor the mains power at the power grid end in real time, and when there is an abnormality in the mains power at the power grid end, control the current grid-connected mode to switch to the off-grid mode.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the load power supply control method as described in any one of claims 1 to 6 is implemented.

9. A power supply control device, characterized in that: The power supply control device comprises: one or more processors; Memory; One or more applications, wherein the one or more applications are stored in the memory and configured to be executed by the one or more processors, and the one or more applications are configured to: execute the load power supply control method according to any one of claims 1 to 6.

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