Power distribution control method and device for optical storage and charging integrated direct current power supply system

Abstract

The application provides a power distribution control method and device for a light storage and charging integrated direct current power supply system, the method comprising: obtaining a charging power demand P_charge and total available system power P_total; if P_charge < P_total, obtaining residual power, distributing the residual power to a direct current air conditioner channel or a building load channel; if P_charge > P_total exists, obtaining a power gap, reducing the power of the building load channel load according to the power gap and a priority sequence, and distributing the reduced power to a charging gun channel; and distributing corresponding DC / DC modules to each channel according to the power distributed to each channel. The application extends the power supply service of the DC / DC module to building loads such as air conditioners and lighting, improves the utilization rate of the DC / DC module in the charging valley, and reduces the building load according to the priority when the available power is insufficient, thereby ensuring that the charging service is not interrupted.

Description

Technical Field

[0001] This invention relates to the field of power transmission and distribution technology, specifically to a power distribution control method and device for an integrated photovoltaic, energy storage, and charging DC power supply system. Background Technology

[0002] With the rapid development of new energy vehicle charging infrastructure, integrated photovoltaic-storage-charging power stations have become the mainstream solution for highway service areas, commercial buildings, hotels, and other scenarios. Currently, photovoltaic-storage charging stations typically adopt a common DC bus architecture, connecting photovoltaic, energy storage, and grid as source terminals in parallel to the DC bus, and then distributing the output to different charging guns through multiple isolated DC / DC modules in parallel.

[0003] However, the aforementioned integrated photovoltaic-storage-charging power station can only distribute the output of the DC / DC modules to the charging guns, without involving power allocation for building loads. Consequently, the power allocation control method only targets the scheduling of charging power, and can only switch the DC / DC modules between different charging guns. It cannot dynamically allocate modules to building loads such as air conditioning and lighting, resulting in a large number of modules being idle during charging off-peak periods. Furthermore, when the total system power is insufficient, it cannot be reasonably allocated among charging, air conditioning, lighting, monitoring, and other loads, which may lead to charging service interruptions or abnormal building power supply. Summary of the Invention

[0004] To solve the above-mentioned technical problems, the first objective of this invention is to propose a power distribution control method for an integrated photovoltaic, energy storage, and charging DC power supply system.

[0005] The second objective of this invention is to provide a power distribution control device for an integrated photovoltaic, energy storage, and charging DC power supply system.

[0006] The technical solution adopted in this invention is as follows:

[0007] An embodiment of the present invention proposes a power distribution control method for an integrated photovoltaic, energy storage and charging DC power supply system. The DC power supply system includes a charging gun channel, a DC air conditioner channel and a building load channel. The method comprises the following steps: collecting in real time the charging power demand P_charge of the charging gun channel, the air conditioner load power P_ac of the DC air conditioner channel, and the building load power P_bldg of the building load channel; calculating the current total load demand power P_demand according to the charging power demand P_charge, the air conditioner load power P_ac and the building load power P_bldg; acquiring the total available system power P_total; if P_charge < P_total exists, acquiring the surplus power P_surplus according to the difference between the total available system power P_total and the current total load demand power P_demand, distributing power to the charging gun channel according to the charging power demand P_charge, and distributing the surplus power P_surplus to the DC air conditioner channel or the building load channel; if P_charge > P_total exists, acquiring the power deficit P_deficit according to the difference between the current total load demand power P_demand and the total available system power P_total, reducing the power of the building load channel and the DC air conditioner channel from low to high according to the P_deficit and the priority sequence, and distributing the reduced power to the charging gun channel; if P_charge = P_total exists, maintaining the currently distributed power of each channel unchanged; distributing a corresponding DC / DC module to each channel according to the power distributed to each channel.

[0008] The power distribution control method for the integrated photovoltaic, energy storage and charging DC power supply system proposed above according to the present invention may further have the following additional technical features:

[0009] According to an embodiment of the present invention, distributing the corresponding DC / DC module to each channel according to the power distributed to each channel specifically comprises: calculating the number of modules N_c required by the charging channel, the number of modules N_a required by the air conditioner channel, and the number of modules N_b required by the building channel according to the ratio of the charging power demand P_charge, the air conditioner load power P_ac, and the building load power P_bldg to the rated power of a single DC / DC module; when N_c + N_a + N_b ≤ N, directly distributing the DC / DC modules according to the calculated distributed power of each channel, wherein N is the total number of the DC / DC modules; when N_c + N_a + N_b > N, preferentially distributing N_c DC / DC modules to the charging channel, and distributing the remaining DC / DC modules to the air conditioner channel and the building channel from high to low according to the priority sequence.

[0010] According to one embodiment of the present invention, the priority sequence from high to low is: EV (Electric Vehicle) charging load, DC air conditioning system, indoor appliance load, and video surveillance system.

[0011] According to an embodiment of the present invention, the power distribution control method of the above-mentioned photovoltaic-storage-charging integrated DC power supply system further includes: acquiring the real-time photovoltaic power P_pv and the current time period, and controlling the output of the photovoltaic according to the real-time photovoltaic power P_pv and the current time period.

[0012] According to one embodiment of the present invention, controlling the output of photovoltaic power based on the real-time photovoltaic power P_pv and the current time period specifically includes: if the real-time photovoltaic power P_pv is greater than or equal to the sum of the air conditioning load power P_ac and the building load power P_bldg, then controlling the output of photovoltaic power to be allocated to the DC air conditioning channel and the building load channel; determining whether the photovoltaic output has a margin; if so, charging the margin into energy storage; after the energy storage is fully charged, determining whether the photovoltaic output has a margin again; if so, allocating the margin to the charging gun channel; if the real-time photovoltaic power P_pv is less than the sum of the air conditioning load power P_ac and the building load power P_bldg, further determining the current time period; if the current period is a valley period, controlling the energy storage to charge preferentially, with the charging gun channel, DC air conditioning channel, and building load channel directly supplied by a common DC bus; if the current period is a peak period, controlling the energy storage to discharge and supplying power from high to low according to the priority sequence; if the current period is a normal period, controlling the energy storage to remain in standby mode and only participating in scheduling during power shortages.

[0013] According to one embodiment of the present invention, when allocating corresponding DC / DC modules to each channel, the relay corresponding to the target channel is first closed, and after the output voltage of the DC / DC module stabilizes within the voltage range of the target channel, the relay corresponding to the source channel is then opened.

[0014] An embodiment of the second aspect of the present invention proposes a power distribution control apparatus for a photovoltaic-storage-charging integrated DC power supply system, where the DC power supply system includes a charging gun channel, a DC air conditioner channel, and a building load channel. The apparatus includes: an acquisition module, configured to acquire in real time the charging power demand P_charge of the charging gun channel, the air conditioner load power P_ac of the DC air conditioner channel, and the building load power P_bldg of the building load channel; a calculation module, configured to calculate the current total load demand power P_demand according to the charging power demand P_charge, the air conditioner load power P_ac, and the building load power P_bldg; an obtaining module, configured to obtain the total available system power P_total; a distribution module, configured to: if P_charge < P_total exists, obtain the surplus power P_surplus according to the difference between the total available system power P_total and the current total load demand power P_demand, distribute power to the charging gun channel according to the charging power demand P_charge, and distribute the surplus power P_surplus to the DC air conditioner channel or the building load channel; if P_charge > P_total exists, obtain the power deficit P_deficit according to the difference between the current total load demand power P_demand and the total available system power P_total, reduce the power of the building load channel and the DC air conditioner channel from low to high according to the P_deficit and the priority sequence, and distribute the reduced power to the charging gun channel; if P_charge = P_total exists, maintain the currently distributed power of each channel unchanged; and a control module, configured to distribute a corresponding DC / DC module to each channel according to the power distributed to each channel.

[0015] The above-described power distribution control apparatus for the photovoltaic-storage-charging integrated DC power supply system of the present invention further has the following additional technical features:

[0016] According to an embodiment of the present invention, the control module is specifically configured to: calculate the number of required modules N_c for the charging channel, the number of required modules N_a for the air conditioner channel, and the number of required modules N_b for the building channel according to the ratios of the charging power demand P_charge, the air conditioner load power P_ac, and the building load power P_bldg to the rated power of a single DC / DC module; when N_c + N_a + N_b ≤ N, directly distribute DC / DC modules according to the calculated power distributed to each channel, where N is the total number of DC / DC modules; when N_c + N_a + N_b > N, preferentially distribute N_c DC / DC modules to the charging channel, and distribute the remaining DC / DC modules to the air conditioner channel and the building channel from high to low according to the priority sequence.

[0017] According to one embodiment of the present invention, the control module is further configured to: acquire the real-time photovoltaic power P_pv and the current time period, and control the output of the photovoltaic based on the real-time photovoltaic power P_pv and the current time period.

[0018] According to one embodiment of the present invention, when the control module allocates a corresponding DC / DC module to each channel, it first closes the relay corresponding to the target channel, waits for the output voltage of the DC / DC module to stabilize within the voltage range of the target channel, and then opens the relay corresponding to the source channel.

[0019] The beneficial effects of this invention are:

[0020] This invention extends the power supply service of DC / DC modules to building loads such as air conditioning and lighting, improves the utilization rate of DC / DC modules during charging off-peak hours, and can sense the demand of various loads such as charging, air conditioning, and buildings in real time. When the available power is insufficient, it reduces the building load according to priority to ensure that the charging service is uninterrupted, and realizes charging priority guarantee and flexible power supply for building loads.

[0021] Photovoltaic power is prioritized for building load, with surplus power used for energy storage, effectively improving photovoltaic utilization, reducing dependence on the grid, and maximizing photovoltaic self-consumption.

[0022] Peak-valley electricity pricing strategies guide energy storage to charge during off-peak hours and discharge during peak hours, reducing electricity procurement costs and thus lowering overall operating costs. Attached Figure Description

[0023] Figure 1 This is a flowchart of a power distribution control method for an integrated photovoltaic, energy storage, and charging DC power supply system according to an embodiment of the present invention;

[0024] Figure 2 This is a schematic diagram of the structure of an integrated photovoltaic, energy storage, and charging DC power supply system according to an embodiment of the present invention;

[0025] Figure 3 This is a flowchart illustrating the allocation of corresponding DC / DC modules to each channel according to an embodiment of the present invention;

[0026] Figure 4 This is a flowchart of a power distribution control method for an integrated photovoltaic, energy storage, and charging DC power supply system according to another embodiment of the present invention;

[0027] Figure 5 This is a block diagram of a power distribution control device for an integrated photovoltaic, energy storage, and charging DC power supply system according to an embodiment of the present invention. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] Figure 1 This is a flowchart of a power distribution control method for an integrated photovoltaic, energy storage, and charging DC power supply system according to an embodiment of the present invention. Figure 2 This is a schematic diagram of a photovoltaic, energy storage, and charging integrated DC power supply system according to an embodiment of the present invention.

[0030] like Figure 2 As shown, the DC power supply system includes: a charging gun channel, a DC air conditioning channel, and a building load channel. A common DC bus 1 connects to photovoltaic, energy storage, and the power grid. The input terminals of multiple DC / DC modules are connected in parallel to the common DC bus 1. The input terminals of the power switching matrix 300 are connected to the corresponding output terminals of the DC / DC modules, and the output terminals of the power switching matrix 300 are connected to the charging gun channel, DC air conditioning channel, and building load channel. The charging gun channel is connected to the EV charging load, and its output voltage is adjustable from 200V to 1000V. The DC air conditioning channel is connected to the DC air conditioning system, and it outputs 750V DC voltage. The building load channel is connected to the building loads (indoor appliance loads, video surveillance system), providing power to LED lighting, DC appliances, and video surveillance, and it outputs 400V DC voltage.

[0031] like Figure 1 As shown, the power distribution control method based on the above-mentioned photovoltaic-storage-charging integrated DC power supply system includes the following steps:

[0032] S1 collects in real time the charging power demand P_charge of the charging gun channel, the air conditioning load power P_ac of the DC air conditioning channel, and the building load power P_bldg of the building load channel.

[0033] S2, calculate the current total load demand power P_demand based on the charging power demand P_charge, the air conditioning load power P_ac, and the building load power P_bldg.

[0034] P_demand=P_charge+P_ac+P_bldg.

[0035] S3, obtain the total available power of the system, P_total.

[0036] Specifically, the total available power of the system, P_total, is the total power that photovoltaic, energy storage, and grid can provide.

[0037] S4, if P_charge < P_total exists, the surplus power P_surplus is obtained according to the difference between the total available system power P_total and the current total load demand power P_demand, power is allocated to the charging gun channel according to the charging power demand P_charge, and the surplus power P_surplus is allocated to the DC air conditioner channel or the building load channel.

[0038] Specifically, when P_charge < P_total, it is determined as a power surplus state, and the surplus power P_surplus = P_total - P_charge is calculated. At this time, power is directly allocated to the charging gun channel according to the charging power demand P_charge, and then the surplus power P_surplus is allocated to the DC air conditioner channel or the building load channel as needed.

[0039] S5, if P_charge > P_total exists, the power deficit P_deficit is obtained according to the difference between the current total load demand power P_demand and the total available system power P_total, the power of the building load channel and the DC air conditioner channel is reduced from low to high according to P_deficit and the priority sequence, and the reduced power is allocated to the charging gun channel.

[0040] Specifically, when P_charge > P_total, it is determined as a power deficit state. The power deficit P_deficit = P_charge - P_total is calculated, the building load reduction process is triggered, and the building loads (monitoring system → indoor lighting and DC household appliances → DC air conditioning system) are reduced level by level from low to high according to the priority sequence, so that the released DC / DC modules are recycled to the charging channel to ensure the charging service.

[0041] The priority sequence is:

[0042] First level (highest priority): EV charging load. The charging service always maintains the highest priority and does not participate in reduction.

[0043] Second level: DC air conditioning system. The air conditioner load is large but has thermal inertia, and short-term reduction will not cause a significant temperature change immediately.

[0044] Third level: indoor lighting and DC household appliances. The lighting load can be reduced by dimming or partial turning-off, and the household appliance load has certain elasticity.

[0045] Fourth level (lowest priority): video monitoring system. The monitoring load is usually small and equipped with a self-provided power supply, and the reduction has the least impact on user experience.

[0046] In other words, the priority sequence from high to low is: EV charging load, DC air conditioning system, indoor appliance load, and video surveillance system.

[0047] S6. If P_charge = P_total, then maintain the current power allocation for each channel unchanged.

[0048] Specifically, if P_charge = P_total, it means the system is in a balanced state, and the current allocation remains unchanged.

[0049] S7 allocates the corresponding DC / DC module to each channel according to the power allocated to each channel.

[0050] Specifically, based on the power allocated to each channel, the relays of the power switching matrix 300 are controlled to allocate the corresponding DC / DC module to each channel. This extends the power supply service of the DC / DC module to building loads such as air conditioning and lighting, improving the utilization rate of the DC / DC module during off-peak charging periods. Furthermore, it can sense the demands of various loads such as charging, air conditioning, and building loads in real time, and reduce building loads according to priority when available power is insufficient, ensuring uninterrupted charging service and achieving priority charging and flexible power supply to building loads.

[0051] In one embodiment of the present invention, such as Figure 3 As shown, DC / DC modules are allocated to each channel according to the power allocated to each channel, specifically including:

[0052] S71, based on the ratio of charging power demand P_charge, air conditioning load power P_ac, building load power P_bldg to the rated power of a single DC / DC module, calculate the number of modules required for the charging channel N_c, the number of modules required for the air conditioning channel N_a, and the number of modules required for the building channel N_b.

[0053] Specifically, the number of modules required for each channel is rounded up based on the calculation results. For example, if the ratio of the charging power demand P_charge to the rated power of a single DC / DC module is 2.6, then the number of modules N_c required for the charging channel is 3.

[0054] S72, when N_c+N_a+N_b≤N, the DC / DC modules are directly allocated according to the calculated power allocated to each channel, where N is the total number of DC / DC modules.

[0055] S73, when N_c+N_a+N_b> N, prioritize N_c DC / DC modules to the charging channel, and allocate the remaining DC / DC modules to the DC air conditioning channel and building channel in order of priority from high to low.

[0056] Specifically, when N_c+N_a+N_b≤N, it indicates that there are enough DC / DC modules, and DC / DC modules are directly allocated according to the calculated value; when N_c+N_a+N_b>N, N_c DC / DC modules are prioritized to be allocated to the charging channel, and the remaining modules are allocated to the air conditioning channel and building channel according to the priority sequence. The insufficient part is recorded as a power gap.

[0057] In a typical scenario, the DC / DC module allocation ratio is approximately N-2 / 1 / 1, meaning N-2 modules are used for EV charging loads, 1 module for DC air conditioning systems, and 1 module for building loads. However, this ratio is not fixed but dynamically adjusted based on real-time load conditions.

[0058] In one embodiment of the present invention, the power distribution control method of the above-mentioned photovoltaic-storage-charging integrated DC power supply system further includes: acquiring the real-time photovoltaic power P_pv and the current time period, and controlling the output of the photovoltaic based on the real-time photovoltaic power P_pv and the current time period.

[0059] Furthermore, such as Figure 4 As shown, the photovoltaic output is controlled based on the real-time photovoltaic power P_pv and the current time period, specifically including:

[0060] S80, determine whether there exists a photovoltaic real-time power P_pv that is greater than or equal to the sum of the air conditioning load power P_ac and the building load power P_bldg (P_pv≥P_ac+P_bldg).

[0061] S81, if the real-time photovoltaic power P_pv is greater than or equal to the sum of the air conditioning load power P_ac and the building load power P_bldg, then control the photovoltaic output to be distributed to the DC air conditioning channel and the building load channel.

[0062] S82 determines whether there is a margin in photovoltaic output.

[0063] S83, if so, will charge the remaining amount into the energy storage.

[0064] S84, determine whether there is a margin in photovoltaic output after the energy storage is fully charged.

[0065] S85, if so, allocate the remaining capacity to the charging gun channel.

[0066] S86. If the real-time photovoltaic power P_pv is less than the sum of the air conditioning load power P_ac and the building load power P_bldg, then further determine the current time period.

[0067] S87 If it is currently during off-peak hours, the energy storage will be prioritized for charging, and the charging gun channel, DC air conditioning channel and building load channel will be directly supplied by the common DC bus.

[0068] S88, if it is currently in a peak power period, controls the energy storage to discharge and supplies power in a priority sequence from high to low.

[0069] S89, if it is currently in a normal period, controls the energy storage to remain in standby mode and only participates in scheduling during power shortages.

[0070] Specifically, when the real-time photovoltaic power P_pv is greater than or equal to the sum of the air conditioning load power P_ac and the building load power P_bldg (P_pv ≥ P_ac + P_bldg), the photovoltaic power is preferentially allocated to the DC air conditioning channel and the building load channel to achieve local consumption. If there is still a surplus after allocation to the DC air conditioning channel and the building load channel, the surplus photovoltaic power is first used to charge the energy storage to improve the photovoltaic utilization rate. If the energy storage is fully charged and there is still a surplus, the surplus power can be allocated to the charging gun channel to participate in EV charging.

[0071] When P_pv < P_ac + P_bldg, a peak-valley electricity price coordination strategy is implemented. If the current period is a valley electricity period, the energy storage is prioritized for charging, and the charging gun channel, DC air conditioning channel, and building load channel are directly supplied by the common DC bus, reducing the occupancy of the DC / DC module. If the current period is a peak electricity period, the energy storage battery discharges according to a priority sequence from high to low, prioritizing the supply to the charging gun channel, reducing the amount of grid procurement during peak electricity periods. If the current period is a normal period, the energy storage remains in standby mode, participating in dispatch only during power shortages. This maximizes photovoltaic self-consumption and achieves economical operation under peak-valley electricity prices, realizing the system's optimal economic operation.

[0072] In an embodiment of the present invention, when allocating a corresponding DC / DC module to each channel, the relay corresponding to the target channel is first closed, and after the output voltage of the DC / DC module stabilizes within the voltage range of the target channel, the relay corresponding to the source channel is then opened.

[0073] Specifically, when assigning the corresponding DC / DC module to each channel, the relay of the target channel is first closed to establish a connection. At this time, the module is simultaneously connected to both the source and target channels. However, due to the load on the target channel, the module's output voltage begins to transition towards the target voltage. The module waits for its output voltage to stabilize within the target channel's voltage range (a delay of 50ms to 200ms, depending on the module's voltage regulation rate) before disconnecting the relay of the source channel, completing the switch from the source channel to the target channel. Thus, this smooth transition strategy of first closing the target channel and then disconnecting the source channel avoids voltage surges and protects the safe operation of the charging gun and building electrical equipment.

[0074] In summary, the power distribution control method of the photovoltaic-storage-charging integrated DC power supply system according to embodiments of the present invention extends the power supply service of the DC / DC module to building loads such as air conditioning and lighting, improving the utilization rate of the DC / DC module during charging off-peak hours. Furthermore, it can sense the demands of various loads such as charging, air conditioning, and buildings in real time, and reduce building loads according to priority when available power is insufficient, ensuring uninterrupted charging service and achieving priority charging and flexible power supply to building loads. Photovoltaic power is prioritized for building loads, with the surplus used to charge energy storage, effectively improving photovoltaic utilization, reducing dependence on the grid, and maximizing photovoltaic self-consumption. Peak-valley pricing strategies guide energy storage to charge during off-peak hours and discharge during peak hours, reducing electricity procurement costs and thus lowering overall operating costs.

[0075] Corresponding to the power distribution control method for the integrated photovoltaic-storage-charging DC power supply system described above, this invention also proposes a power distribution control device for the integrated photovoltaic-storage-charging DC power supply system. Since the device embodiments of this invention correspond to the method embodiments described above, details not disclosed in the device embodiments can be found in the method embodiments described above, and will not be repeated here.

[0076] Figure 5 This is a block diagram of a power distribution control device for an integrated photovoltaic, energy storage, and charging DC power supply system according to an embodiment of the present invention, wherein, as shown... Figure 2 As shown, the DC power supply system includes: a charging gun channel, a DC air conditioning channel, and a building load channel.

[0077] like Figure 5 As shown, the power distribution control device of the integrated photovoltaic, energy storage and charging DC power supply system includes: acquisition module 1, calculation module 2, acquisition module 3, distribution module 4 and control module 5.

[0078] wherein the acquisition module 1 is configured to acquire in real time the charging power demand P_charge of the charging gun channel, the air conditioning load power P_ac of the DC air conditioning channel, and the building load power P_bldg of the building load channel; the calculation module 2 is configured to calculate the current total load demand power P_demand according to the charging power demand P_charge, the air conditioning load power P_ac and the building load power P_bldg; the acquisition module 3 is configured to acquire the total available system power P_total; the allocation module 4 is configured to: if P_charge < P_total exists, acquire the surplus power P_surplus according to the difference between the total available system power P_total and the current total load demand power P_demand, allocate power to the charging gun channel according to the charging power demand P_charge, and allocate the surplus power P_surplus to the DC air conditioning channel or the building load channel; if P_charge > P_total exists, acquire the power deficit P_deficit according to the difference between the current total load demand power P_demand and the total available system power P_total, reduce the power of the building load channel and the DC air conditioning channel from low to high according to the P_deficit and the priority sequence, and allocate the reduced power to the charging gun channel; if P_charge = P_total exists, maintain the currently allocated power of each channel unchanged; the control module 5 is configured to allocate a corresponding DC / DC module to each channel according to the power allocated to each channel.

[0079] According to an embodiment of the present invention, the control module 5 is specifically configured to: calculate the number of modules N_c required for the charging channel, the number of modules N_a required for the air conditioning channel, and the number of modules N_b required for the building channel according to the ratios of the charging power demand P_charge, the air conditioning load power P_ac, and the building load power P_bldg to the rated power of a single DC / DC module; when N_c + N_a + N_b ≤ N, directly allocate DC / DC modules according to the calculated power allocated to each channel, where N is the total number of DC / DC modules; when N_c + N_a + N_b > N, preferentially allocate N_c DC / DC modules to the charging channel, and allocate the remaining DC / DC modules to the DC air conditioning channel and the building channel from high to low according to the priority sequence.

[0080] According to an embodiment of the present invention, the control module 5 is further configured to: acquire the real-time photovoltaic power P_pv and the current time period, and control the output of the photovoltaic according to the real-time photovoltaic power P_pv and the current time period.

[0081] According to an embodiment of the present invention, when allocating the corresponding DC / DC module to each channel, the control module 5 first closes the relay corresponding to the target channel, waits until the output voltage of the DC / DC module stabilizes within the voltage range of the target channel, and then disconnects the relay corresponding to the source channel.

[0082] In summary, the power distribution control device of the photovoltaic-storage-charging integrated DC power supply system according to embodiments of the present invention extends the power supply service of the DC / DC module to building loads such as air conditioning and lighting, improving the utilization rate of the DC / DC module during charging off-peak hours. It can also sense the demands of various loads such as charging, air conditioning, and buildings in real time, and reduce building loads according to priority when available power is insufficient, ensuring uninterrupted charging service and achieving priority charging and flexible power supply to building loads. Photovoltaic power is prioritized for building loads, with the surplus charged into energy storage, effectively improving photovoltaic utilization, reducing dependence on the grid, and maximizing photovoltaic self-consumption. Peak-valley pricing strategies guide energy storage to charge during off-peak hours and discharge during peak hours, reducing electricity procurement costs and thus lowering overall operating costs.

[0083] In the description of this invention, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example.

[0084] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A power distribution control method for an integrated photovoltaic-storage-charging DC power supply system, characterized in that, The DC power supply system includes a charging gun channel, a DC air conditioner channel and a building load channel, and the method comprises the following steps: Collect in real time the charging power demand P_charge of the charging gun channel, the air conditioner load power P_ac of the DC air conditioner channel, and the building load power P_bldg of the building load channel; Calculate the current total load demand power P_demand according to the charging power demand P_charge, the air conditioner load power P_ac and the building load power P_bldg; Obtain the total available system power P_total; If P_charge<P_total exists, obtain the surplus power P_surplus according to the difference between the total available system power P_total and the current total load demand power P_demand, allocate power to the charging gun channel according to the charging power demand P_charge, and allocate the surplus power P_surplus to the DC air conditioner channel or the building load channel; If P_charge>P_total exists, obtain the power deficit P_deficit according to the difference between the current total load demand power P_demand and the total available system power P_total, reduce the power of the building load channel and the DC air conditioner channel from low to high according to the P_deficit and the priority sequence, and allocate the reduced power to the charging gun channel; If P_charge = P_total exists, keep the currently allocated power of each channel unchanged; Allocate a corresponding DC / DC module to each channel according to the power allocated to each channel.

2. The power distribution control method for the photovoltaic-storage-charging integrated DC power supply system according to claim 1, characterized in that, Allocating a corresponding DC / DC module to each channel according to the power allocated to each channel specifically comprises: Calculate the number of modules N_c required for the charging channel, the number of modules N_a required for the air conditioner channel, and the number of modules N_b required for the building channel according to the ratios of the charging power demand P_charge, the air conditioner load power P_ac, and the building load power P_bldg to the rated power of a single DC / DC module; When N_c+N_a+N_b≤N, directly allocate DC / DC modules according to the calculated power allocated to each channel, where N is the total number of DC / DC modules; When N_c+N_a+N_b>N, preferentially allocate N_c DC / DC modules to the charging channel, and allocate the remaining DC / DC modules to the DC air conditioner channel and the building channel from high to low according to the priority sequence.

3. The power distribution control method for the integrated photovoltaic-storage-charging DC power supply system according to claim 1, characterized in that, The priority sequence from high to low is: EV charging load, DC air conditioning system, indoor household appliance load, and video surveillance system.

4. The power distribution control method for the photovoltaic-storage-charging integrated DC power supply system according to claim 1, characterized in that, The method further comprises: Obtain the photovoltaic real-time power P_pv and the current time period, and control the output of the photovoltaic according to the photovoltaic real-time power P_pv and the current time period.

5. The power distribution control method for the photovoltaic-storage-charging integrated DC power supply system according to claim 4, characterized in that, Controlling the output of the photovoltaic according to the photovoltaic real-time power P_pv and the current time period specifically comprises: If the real-time photovoltaic power P_pv is greater than or equal to the sum of the air conditioning load power P_ac and the building load power P_bldg, the output of the photovoltaic is controlled to be distributed to the DC air conditioning channel and the building load channel; Determine whether there is a surplus in the photovoltaic output; If yes, charge the surplus into the energy storage; After the energy storage is fully charged, determine again whether there is a surplus in the photovoltaic output; if yes, distribute the surplus to the charging gun channel; If the real-time photovoltaic power P_pv is less than the sum of the air conditioning load power P_ac and the building load power P_bldg, further determine the current time period; If it is currently in the valley electricity period, control the energy storage to supply power preferentially, and the charging gun channel, the DC air conditioning channel and the building load channel are directly powered by the common DC bus; If it is currently in the peak electricity period, control the energy storage to discharge and supply power in descending order according to the priority sequence; If it is currently in the flat electricity period, control the energy storage to maintain a standby state, and participate in scheduling only when there is a power gap.

6. The power distribution control method for the photovoltaic-storage-charging integrated DC power supply system according to claim 1, characterized in that, When allocating the corresponding DC / DC module for each channel, first close the relay corresponding to the target channel, wait until the output voltage of the DC / DC module stabilizes within the voltage range of the target channel, and then disconnect the relay corresponding to the source channel.

7. A power distribution control device for an integrated photovoltaic-storage-charging DC power supply system, characterized in that, The DC power supply system includes: a charging gun channel, a DC air conditioning channel and a building load channel, and the apparatus includes: An acquisition module, configured to acquire in real time the charging power demand P_charge of the charging gun channel, the air conditioning load power P_ac of the DC air conditioning channel, and the building load power P_bldg of the building load channel; A calculation module, configured to calculate the current total load demand power P_demand according to the charging power demand P_charge, the air conditioning load power P_ac and the building load power P_bldg; An acquisition module, configured to acquire the total available system power P_total; An allocation module, configured to: if P_charge<P_total exists, acquire the surplus power P_surplus according to the difference between the total available system power P_total and the current total load demand power P_demand, allocate power to the charging gun channel according to the charging power demand P_charge, and allocate the surplus power P_surplus to the DC air conditioning channel or the building load channel; if P_charge>P_total exists, acquire the power deficit P_deficit according to the difference between the current total load demand power P_demand and the total available system power P_total, reduce the power of the building load channel and the DC air conditioning channel in ascending order according to the P_deficit and the priority sequence, and allocate the reduced power to the charging gun channel; if P_charge = P_total exists, maintain the currently allocated power of each channel unchanged; A control module, configured to allocate a corresponding DC / DC module for each channel according to the power allocated to each channel.

8. The power distribution control device for the photovoltaic-storage-charging integrated DC power supply system according to claim 7, characterized in that, The control module is specifically used for: Based on the ratios of charging power demand P_charge, air conditioning load power P_ac, building load power P_bldg to the rated power of a single DC / DC module, calculate the number of modules required for the charging channel N_c, the number of modules required for the air conditioning channel N_a, and the number of modules required for the building channel N_b. When N_c+N_a+N_b≤N, the DC / DC modules are directly allocated according to the calculated power allocation for each channel, where N is the total number of DC / DC modules; When N_c + N_a + N_b > N, N_c DC / DC modules will be preferentially allocated to the charging channel, and the remaining DC / DC modules will be allocated to the DC air conditioning channel and the building channel in descending order of priority.

9. The power distribution control device for the photovoltaic-storage-charging integrated DC power supply system according to claim 7, characterized in that, The control module is also used to: acquire the real-time photovoltaic power P_pv and the current time period, and control the output of the photovoltaic based on the real-time photovoltaic power P_pv and the current time period.

10. The power distribution control device for the photovoltaic-storage-charging integrated DC power supply system according to claim 7, characterized in that, When the control module assigns a corresponding DC / DC module to each channel, it first closes the relay corresponding to the target channel, waits for the output voltage of the DC / DC module to stabilize within the voltage range of the target channel, and then disconnects the relay corresponding to the source channel.

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