CN108667114A - Power supply system and control method for power supply system - Google Patents

Abstract

The invention discloses the control methods of a kind of power supply system and power supply system, power supply system includes photovoltaic cell group, energy-storage system, photovoltaic DC-to-AC converter and controller, photovoltaic cell group includes multiple photovoltaic cells, photovoltaic cell group is connected by the photovoltaic DC-to-AC converter and power grid or load, energy-storage system is connected in parallel with photovoltaic cell group, energy-storage system is connected by photovoltaic DC-to-AC converter and power grid or with load, and control method includes：Controller obtains control information, and controller controls at least one of photovoltaic cell group and energy-storage system to power grid or load supplying according to the control information.In such manner, it is possible to reduce the burden of power grid, the utilization rate of regenerative resource is improved.

Description

Power supply system and control method for power supply system

technical field

The invention relates to the technical field of power electronics, in particular to a control method and a power supply system for a power supply system.

Background technique

With the development of green and renewable energy, photovoltaic power generation has emerged as the times require, but most photovoltaic power generation is concentrated during the day, which will waste excess photovoltaic energy.

Existing photovoltaic power supply systems use photovoltaic cells (Photovoltaic, PV) to supply power grids or loads after conversion by inverters and bidirectional direct current-direct current (DC-DC). Due to the limited conversion capability of the inverter, and the power is converted twice by the inverter and DC-DC in this way, the utilization rate of photovoltaic power generation is reduced, and the power generation efficiency is reduced, which cannot meet the needs of the grid and load side. Moreover, most of the existing new energy storage systems are stored at the grid side, and product development costs are high. Although they can solve the problem of excess energy storage, they also increase the burden and risk of the grid.

How to efficiently utilize photovoltaic power generation while reducing the burden on the power grid has become an urgent problem to be solved in the photovoltaic industry at this stage.

Contents of the invention

The invention provides a control method for a power supply system and a power supply system, which can reduce the burden on the power grid and improve the utilization rate of renewable energy.

According to a method for controlling a power supply system proposed in an embodiment of the present invention, the power supply system includes: a photovoltaic cell group, an energy storage system, a photovoltaic inverter, and a controller, and the photovoltaic cell group includes N photovoltaic cells, where N is An integer greater than 1, the photovoltaic cell group is connected to the grid or load through the photovoltaic inverter, the energy storage system is connected in parallel with the photovoltaic cell group, and the energy storage system is connected to the photovoltaic cell group through the photovoltaic inverter The power grid is connected to the load, and the control method includes: the controller controls at least one of the photovoltaic cell group and the energy storage system to supply power to the power grid or the load.

According to the control method of the power supply system proposed in the embodiment of the present invention, the renewable energy can be fully absorbed by adding multiple photovoltaic cells in the power supply system, and the energy storage system is arranged on the side of the photovoltaic cell group, and the photovoltaic cell is controlled by the controller Groups and/or energy storage systems supply power to the grid or loads, thereby reducing the burden on the grid and increasing the utilization of renewable energy.

According to the power supply system proposed in another embodiment of the present invention, the power supply system includes: a photovoltaic cell group, an energy storage system, a photovoltaic inverter and a controller, and the photovoltaic cell group includes N photovoltaic cells, where N is greater than 1 integer; the photovoltaic cell group is connected to the grid or load through the photovoltaic inverter; the energy storage system is connected in parallel with the photovoltaic cell group, and the energy storage system is connected to the photovoltaic cell group through the photovoltaic inverter The grid or the load is connected; the controller is used to control at least one of the photovoltaic cell group and the energy storage system to supply power to the grid or the load.

According to the power supply system proposed by the embodiment of the present invention, renewable energy can be fully absorbed by adding multiple photovoltaic cells in the power supply system, and the energy storage system is arranged on the side of the photovoltaic cell group, and the controller is used to control the photovoltaic cell group and/or The energy storage system supplies power to the grid or loads, thereby reducing the burden on the grid and increasing the utilization rate of renewable energy.

Description of drawings

Fig. 1 is a schematic flowchart of a control method of a power supply system according to an embodiment of the present invention;

Fig. 2 is a schematic flowchart of a control method of a power supply system according to another embodiment of the present invention;

3 is a flowchart of a control method of a power supply system according to another embodiment of the present invention;

Fig. 4 is a schematic block diagram of a power supply system according to an embodiment of the present invention;

5 is a schematic block diagram of a power supply system according to another embodiment of the present invention;

Fig. 6 is a schematic block diagram of a power supply system according to another embodiment of the present invention.

Detailed ways

Embodiments of the present invention are described in detail below, examples of which are shown in the drawings, wherein the same or similar reference numerals designate the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the figures are exemplary and are intended to explain the present invention and should not be construed as limiting the present invention.

The control method of the power supply system and the power supply system implementing the control method according to the embodiments of the present invention will be described below with reference to the accompanying drawings.

Fig. 1 is a flowchart of a method for controlling a power supply system according to an embodiment of the present invention. The method in Fig. 1 can be realized by the controller of the power supply system. The power supply system includes a photovoltaic battery group, an energy storage system, a photovoltaic inverter and a controller. The photovoltaic battery group includes N photovoltaic cells, where N is an integer greater than 1. The photovoltaic battery group is connected to the grid or load through a photovoltaic inverter. The energy system is connected in parallel with the photovoltaic cell group, and the energy storage system is connected to the grid or to the load through the photovoltaic inverter.

The control method of the power supply system includes:

101. The controller acquires control information.

102. The controller controls at least one of the photovoltaic cell group and the energy storage system to supply power to the grid or the load according to the control information.

According to the control method of the power supply system proposed in the embodiment of the present invention, the renewable energy can be fully absorbed by adding multiple photovoltaic cells in the power supply system, and the energy storage system is arranged on the side of the photovoltaic cell group, and the photovoltaic cell is controlled by the controller Groups and/or energy storage systems supply power to the grid or loads, thereby reducing the burden on the grid and increasing the utilization of renewable energy.

In an embodiment of the present invention, the controller can select at least one of the photovoltaic cell group and the energy storage system to supply power to the grid or the load according to the control information. The control information may be an external control signal received by the controller, such as a signal directly input from the outside and suitable for power supply by a photovoltaic cell group. The control information may also be that the controller chooses to use the photovoltaic battery group and/or the energy storage system for power supply according to the power generated by the photovoltaic battery group and the demanded power of the grid or load.

The number of photovoltaic cells in the photovoltaic cell group in the power supply system of this application is greater than 1, that is, this application adds a new photovoltaic cell, so that the photovoltaic cell can fully absorb light energy, reduce the loss of light energy, and make light energy be effectively used.

In the embodiment of the present application, by adding a plurality of photovoltaic cells, the photovoltaic energy can be fully absorbed, and more photovoltaic cell energy can be stored in the energy storage system while satisfying the power supply for the grid or load, increasing the storage capacity of the energy storage battery. Energy efficiency, when the energy of the photovoltaic battery pack is insufficient, it can supply power to the grid or load, and improve the utilization rate of renewable energy. In this way, the cumulative power generation can be increased when the power of the photovoltaic inverter is constant.

The existing power supply system scheme takes the power grid as the coupling point, installs energy storage batteries at the power grid end, and stores electricity at the power grid end. In this way, as the demand for electricity increases, the installed capacity of power generation equipment and power consumption equipment in the power grid will increase. , the factors that need to be controlled will increase, and at the same time the burden on the power grid will increase, the difficulty of power grid regulation will increase, and the expenditure will increase accordingly. In this application, the energy storage system is connected in parallel with the photovoltaic battery group, and the energy storage system is arranged on the side of the photovoltaic battery group, which can reduce the burden on the grid side and reduce expenditure.

In addition, in the existing off-grid solution of the power supply system, the photovoltaic battery is connected with the inverter, DC-DC, and the load in sequence to convert the current and voltage. Since the conversion power of the inverter itself is limited, this limits the upper limit of the power at the load end. , cannot fully meet the demand of high power load. The photovoltaic cell group of the present application includes a plurality of photovoltaic cells, and the photovoltaic cell group is connected to the load through a photovoltaic inverter. In addition, the photovoltaic cell group is also connected to the energy storage battery in the energy storage system through a bidirectional DC-DC, so through When the energy storage battery supplies power to the load, the convertible power in the circuit is no longer limited, which can improve the utilization rate of the photovoltaic battery and improve the discharge efficiency. In the design of this application, multiple photovoltaic cells share one photovoltaic inverter. Compared with simply adding one or more sets of photovoltaic cells, inverters, and DC-DC combined design, while meeting the load power demand, The number of components can also be saved.

The energy storage system in this application includes M energy storage batteries and M bidirectional DC/DCs, wherein the M energy storage batteries are connected in parallel, and the M energy storage batteries correspond to the M bidirectional DC/DCs one by one, and M is positive integer. Each energy storage battery is connected to the photovoltaic cell group through a bidirectional DC/DC, and each energy storage battery is also connected to the grid or load through a photovoltaic inverter. In this way, by adding a plurality of energy storage batteries, the power of the photovoltaic battery group is stored in the energy storage battery when the electricity supplied to the grid or the load is still remaining, so that it can be used when the electricity of the photovoltaic battery group is insufficient. Multiple energy storage batteries make the storage capacity larger and can improve light utilization.

Further, by adding a plurality of energy storage batteries, a higher power photovoltaic inverter can be supported, which can prolong the power supply time for the grid or load.

It should be understood that the embodiments of the present application can be applied to grid-connected or off-grid applications, and there is no limit to the application scenarios of grid-connected or off-grid. supply power to the load.

The method for selecting a suitable power supply system for a grid or a load will be described in detail below with reference to the specific embodiments shown in FIG. 2 and FIG. 3 .

Fig. 2 is a schematic flowchart of a control method of a power supply system according to another embodiment of the present invention. The control method in Fig. 2 can be realized by the controller of the power supply system. The power supply system includes a photovoltaic battery group, an energy storage system, a photovoltaic inverter and a controller. The photovoltaic battery group includes N photovoltaic cells, where N is an integer greater than 1. The photovoltaic battery group is connected to the grid or load through a photovoltaic inverter. The energy system is connected in parallel with the photovoltaic cell group, and the energy storage system is connected to the grid or to the load through the photovoltaic inverter.

The control method of the power supply system includes:

201. The controller receives a control signal.

The control signal can be received by the controller from the outside, or it can be received by the controller from the photovoltaic cell group or the power grid or the load. This application does not limit this, as long as the signal used to control the power supply to the grid or load is Within the protection scope of this application.

202. The controller controls at least one of the photovoltaic cell group and the energy storage system to supply power to the grid or the load according to the control signal.

The power grid or load in this application can be powered solely by the photovoltaic cell group, for example, when the sunlight energy is sufficient, that is, the power generated by the photovoltaic cell group is sufficient to meet the demand of the load or the power grid. At this time, when the energy in the energy storage system is not full, the photovoltaic battery pack can also be controlled to charge the energy storage battery in the energy storage system.

The grid or load in this application can also be powered solely by the energy storage system. For example, when the sunlight energy is insufficient on cloudy and rainy days, and the energy of the photovoltaic battery pack is exhausted at night, the energy storage battery in the energy storage system can supply power to the grid or load alone.

According to the control method of the power supply system proposed in the embodiment of the present invention, the renewable energy can be fully absorbed by adding multiple photovoltaic cells in the power supply system, and the energy storage system is arranged on the side of the photovoltaic cell group, and the photovoltaic cell is controlled by the controller Groups and/or energy storage systems supply power to the grid or loads, thereby reducing the burden on the grid and increasing the utilization of renewable energy.

In this application, the photovoltaic cell group and the energy storage battery in the energy storage system can also jointly supply power to the grid or load. For example, when the energy of the photovoltaic battery pack is not enough to provide the power demand required by the grid or load on rainy days, the energy storage battery in the energy storage system can be used to supply power to the grid or load to supplement the power supply demand.

The specific method of how to select the power supply system according to the generated power and power demand will be described in detail below with reference to FIG. 3 .

Fig. 3 is a flowchart of a control method of a power supply system according to another embodiment of the present invention. The control method in Fig. 3 can be realized by the controller of the power supply system. The power supply system includes a photovoltaic battery group, an energy storage system, a photovoltaic inverter and a controller. The photovoltaic battery group includes N photovoltaic cells, where N is an integer greater than 1. The photovoltaic battery group is connected to the grid or load through a photovoltaic inverter. The energy system is connected in parallel with the photovoltaic cell group, and the energy storage system is connected to the grid or to the load through the photovoltaic inverter.

The control method of the power supply system includes:

301. The controller obtains the required power of the power grid or the load.

In an embodiment of the present invention, the controller may receive the required power of the power grid or the load detected by the CT.

302. The controller obtains the power generated by the photovoltaic cell group.

In an embodiment of the present invention, the controller may receive the generated power of the photovoltaic cell group detected by the CT.

Steps 301 and 302 detect power through CT. It should be understood that the controller can also obtain power through other methods, which is not limited in this application.

303. Whether the generated power of the photovoltaic cell group is lower than the required power of the grid or the load.

Compare the generated power of the photovoltaic cell group with the demanded power on the grid side or load side.

304. Whether the generating power of the photovoltaic cell set is zero.

If it is determined in step 303 that the generated power of the photovoltaic cell is less than the required power of the grid or the load, the step proceeds to step 304 and continues to determine whether the generated power of the photovoltaic cell group is zero.

305. The controller controls the energy storage battery in the energy storage system to supply power to the grid or the load.

If it is obtained in 303 that the generated power of the photovoltaic battery group is less than the demanded power of the grid or load, proceed to 304 to obtain that the generated power of the photovoltaic battery group is zero, and at this time only the energy storage battery in the energy storage system can be used to supply power to the grid or load.

306. The controller controls the photovoltaic battery group and the energy storage battery in the energy storage system to supply power to the grid or the load at the same time.

If the generated power of the photovoltaic battery group obtained in 303 is less than the required power of the grid or the load, and the generated power of the photovoltaic battery group obtained in 304 is not zero, then the photovoltaic battery group is not enough to provide enough power to the grid or load, and the power storage can be used The energy storage battery in the energy system provides supplementary power to the grid or load, and the energy storage battery discharges.

307. Whether the generated power of the photovoltaic cell group is equal to the required power of the grid or the load.

If it is determined in step 303 that the power generated by the photovoltaic cell is not less than the required power of the grid or load, the step proceeds to step 307 to continue to determine whether the generated power of the photovoltaic cell group is equal to the required power of the grid or load.

308. The controller controls the photovoltaic cell group to supply power to the grid or the load.

If it is obtained in 303 that the generated power of the photovoltaic cell group is not less than the required power of the grid or load, proceed to 307 to obtain that the generated power of the photovoltaic cell group is equal to the required power of the grid or load, and then use the photovoltaic cell group to supply power to the grid or load alone.

309. The controller controls the photovoltaic battery and the energy storage battery in the energy storage system to supply power to the grid or the load at the same time. Further, the controller can control the photovoltaic battery pack to charge the energy storage battery in the energy storage system.

If 303 obtains that the generated power of the photovoltaic cell group is not less than the required power of the grid or load, continue to 307 to obtain that the generated power of the photovoltaic cell group is not equal to the required power of the grid or load, and then use the photovoltaic cell group to supply power to the grid or load. The power of the battery pack is still remaining, and the controller can control the photovoltaic battery pack to charge the energy storage battery in the energy storage system.

It should be understood that the energy storage battery in the energy storage system in this application can be charged by the photovoltaic battery pack, or when the charging of the photovoltaic battery pack is not enough to meet the demand, other external methods can be used to charge the energy storage battery to When the standby photovoltaic battery pack provides insufficient power to the load or the grid, the energy storage battery is used to supplement the power supply.

It should be understood that this application can detect the power generated by the photovoltaic cell group, the demand power of the grid or load, and other parameters such as electricity, and all parameters related to charging and discharging requirements are within the scope of protection of this application.

The schematic flowchart of the control method corresponding to the power supply system of the embodiment of the present application is described in detail above with reference to FIGS. 1 to 3 . The schematic block diagram of the power supply system of the embodiment of the present application is described in detail below with reference to FIGS.

Fig. 4 is a schematic block diagram of a power supply system according to an embodiment of the present invention. The power supply system of the embodiment of the present invention includes a photovoltaic cell group 11, an energy storage system 12, a photovoltaic inverter 13, and a controller 15. The photovoltaic cell group includes N photovoltaic cells, and N is an integer greater than 1. The photovoltaic cell group passes through the photovoltaic inverter The inverter is connected to the grid or the load, the energy storage system is connected in parallel with the photovoltaic cell group, and the energy storage system is connected to the grid or the load through the photovoltaic inverter. The controller is used to obtain control information, and control at least one of the photovoltaic battery group and the energy storage system to supply power to the grid or the load according to the control information.

The power supply system in the embodiment of the present invention can be used to supply power to the grid 14 in the grid-connected state, and can also be used to supply power to the load 14 in the off-grid state.

According to the power supply system proposed by the embodiment of the present invention, renewable energy can be fully absorbed by adding multiple photovoltaic cells in the power supply system, and the energy storage system is arranged on the side of the photovoltaic cell group, and the controller is used to control the photovoltaic cell group and/or The energy storage system supplies power to the grid or loads, thereby reducing the burden on the grid, reducing dependence on the grid, and increasing the utilization rate of renewable energy.

The control information in the embodiment of the present invention may be an external control signal received by the controller, for example, a signal directly input from the outside and suitable for power supply by a photovoltaic cell group. At this time, the controller may receive the control signal, and control at least one of the photovoltaic cell group and the energy storage system to supply power to the grid or the load according to the control signal. For example, when the control signal only controls the connection between the energy storage system and the grid or load, the energy storage battery in the energy storage system can be used to supply power to the grid or load.

The control information may also be that the controller chooses to use the photovoltaic battery group and/or the energy storage system for power supply according to the power generated by the photovoltaic battery group and the demanded power of the grid or load. At this time, the controller can be used to obtain the required power of the grid or load, and obtain the generated power of the photovoltaic cell group, and control the photovoltaic cell group and energy storage according to the required power of the grid or the load, and according to the generated power of the photovoltaic cell group At least one of the systems supplies power to a grid or load.

In an embodiment of the present invention, a current transformer (Current transformer, CT) may be used to detect power, a CT may be used to detect power demanded by a power grid, or a CT may be used to detect power demanded by a load. In addition, CT can also be used to detect the power generation of photovoltaic cells.

In addition, in the existing off-grid solution of the power supply system, the photovoltaic battery is connected with the inverter, DC-DC, and the load in sequence to convert the current and voltage. Since the conversion power of the inverter itself is limited, this limits the upper limit of the power at the load end. , cannot fully meet the load requirements. The photovoltaic cell group of the present application includes a plurality of photovoltaic cells, and the photovoltaic cell group is connected to the load through a photovoltaic inverter. In addition, the photovoltaic cell group is also connected to the energy storage battery in the energy storage system through a bidirectional DC-DC, so through When the energy storage battery supplies power to the load, the convertible power in the circuit is no longer limited, which can improve the utilization rate of the photovoltaic battery and improve the discharge efficiency.

The energy storage system in this application includes M energy storage batteries and M bidirectional DC/DCs, wherein the M energy storage batteries are connected in parallel, and the M energy storage batteries correspond to the M bidirectional DC/DCs one by one, and M is positive integer. Each energy storage battery is connected to the photovoltaic cell group through a bidirectional DC/DC, and each energy storage battery is also connected to the grid or load through a photovoltaic inverter. In this way, by adding a plurality of energy storage batteries, the power of the photovoltaic battery group is stored in the energy storage battery when the electricity supplied to the grid or the load is still remaining, so that it can be used when the electricity of the photovoltaic battery group is insufficient. A plurality of energy storage batteries makes the storage capacity larger, reduces the requirement on the capacity of the energy storage battery, and can also improve the utilization rate of light.

In one embodiment of the present invention, if the power generated by the photovoltaic battery is zero, the photovoltaic battery group controller can be used to control the energy storage battery in the energy storage system to supply power to the grid or load.

If the power generated by the photovoltaic cell group is not zero, and the power of the photovoltaic cell is less than the demanded power of the grid or load, the controller is used to control the photovoltaic cell group and the energy storage battery in the energy storage system to supply power to the grid or load at the same time.

If the power of the photovoltaic battery group is equal to the demand power of the grid or load, the controller is used to control the disconnection between the energy storage system and the photovoltaic inverter, and control the photovoltaic battery group to supply power to the grid or load.

If the power of the photovoltaic cell group is greater than the required power of the grid or load, the controller is used to control the photovoltaic cell group to supply power to the grid or load. In addition, the controller is also used to control the photovoltaic battery to charge the energy storage battery in the energy storage system when the power of the photovoltaic battery is greater than the demanded power of the grid or load.

The controller in the power supply system in the embodiment of the present invention can execute the methods shown in the flow charts in FIG. 1 to FIG. 3 , and to avoid repetition, details are not repeated here.

FIG. 5 is a schematic block diagram of a power supply system according to another embodiment of the present invention.

Here, grid connection is taken as an example for illustration. The power supply system in Fig. 5 includes a photovoltaic battery group composed of multiple PV battery panels, an energy storage system, a bidirectional DC-DC, a photovoltaic inverter, and a power grid. The photovoltaic battery pack is connected to the grid through a photovoltaic inverter. The energy storage system is connected to the grid through bidirectional DC-DC and photovoltaic inverters. The bidirectional DC-DC circuit diagram is shown in the figure. Bidirectional DC-DC can realize bidirectional conversion between DC high voltage and DC low voltage. The inductor L is used to store electric energy for step-up or step-down. The switches K1 and K2 are controlled by step-up or step-down switches. When the power of the photovoltaic battery pack is insufficient to provide power to the grid, the energy storage battery in the energy storage system can supplement the power supply to the grid, and the energy storage battery is discharged. The power of the photovoltaic battery pack is enough to provide power to the grid, and when there is surplus, the photovoltaic battery pack can also charge the energy storage battery in the energy storage system.

Fig. 6 is a schematic block diagram of a power supply system according to another embodiment of the present invention. Fig. 6 takes the off-grid state where the power supply system supplies power to the load as an example for illustration. The power supply system shown in Figure 6 is photovoltaic battery pack, DC-AC (Direct Current-Alternating Current, DC/AC) inverter, current sampling module, voltage sampling module, bidirectional DC/DC, voltage sampling module, voltage and current sampling module, The energy storage battery and the battery manager, the battery manager may be the controller in Figure 4.

Photovoltaic battery packs can be connected to loads through DC/AC inverters. The current sampling module is used to collect the current on the DC side of the DC/AC inverter, and transmit the sampling results to the bidirectional DC/DC, so that the output of the bidirectional DC/DC control voltage and current can meet the load requirements. The photovoltaic battery pack is connected with the energy storage battery and the battery manager through a bidirectional DC/DC. The voltage sampling module is used to collect the voltage of the photovoltaic cell group, and transmit the sampling result to the bidirectional DC/DC, so that the bidirectional DC/DC can follow the voltage output of the photovoltaic cell group, and protect the bidirectional DC/DC from being damaged due to overvoltage. The voltage and current acquisition module can be used to collect the current and voltage of the energy storage battery, and transmit the power value calculated according to the sampling result to the bidirectional DC/DC, so that the DC/DC can be charged or discharged. Relay 1 is a battery relay, which is used to control the connection between the energy storage battery and the bidirectional DC/DC.

In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be interpreted as indicating or implying relative importance or implicitly specifying the quantity of indicated technical features. Thus, the features defined as "first" and "second" may explicitly or implicitly include at least one of these features. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless specifically defined otherwise.

In the present invention, unless otherwise clearly specified and limited, terms such as "installation", "connection", "connection" and "fixation" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection , or integrated; it may be mechanically connected or electrically connected; it may be directly connected or indirectly connected through an intermediary, and it may be the internal communication of two components or the interaction relationship between two components, unless otherwise specified limit. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention according to specific situations.

In the description of this specification, descriptions referring to the terms "one embodiment", "some embodiments", "example", "specific examples", or "some examples" mean that specific features described in connection with the embodiment or example , structure, material or characteristic is included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the described specific features, structures, materials or characteristics may be combined in any suitable manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine different embodiments or examples and features of different embodiments or examples described in this specification without conflicting with each other.

Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention, those skilled in the art can make the above-mentioned The embodiments are subject to changes, modifications, substitutions and variations.

Claims (14)

1. A control method of a power supply system, characterized in that the power supply system includes: the photovoltaic battery pack comprises N photovoltaic batteries, N is an integer greater than 1, the photovoltaic battery pack is connected with a power grid or a load through the photovoltaic inverter, the energy storage system is connected with the photovoltaic battery pack in parallel, and the energy storage system is connected with the power grid or the load through the photovoltaic inverter;

the control method comprises the following steps:

the controller acquires control information;

the controller controls at least one of the photovoltaic battery pack and the energy storage system to supply power to the power grid or the load according to the control information.

2. The control method according to claim 1, wherein the energy storage system comprises M energy storage cells and M bidirectional direct current-direct current DC/DC, the M energy storage cells are connected in parallel, the M energy storage cells are in one-to-one correspondence with the M bidirectional DC/DC, M is a positive integer, each energy storage cell is connected with the photovoltaic battery pack through the bidirectional DC/DC, and each energy storage cell is further connected with the grid or the load through the photovoltaic inverter.

3. The method according to claim 1 or 2, characterized in that the control information is a control signal,

wherein,

the controller acquiring control information includes:

the controller receives a control signal;

the controller controlling at least one of the photovoltaic battery pack and the energy storage system to supply power to the power grid or the load according to the control information comprises:

the controller controls at least one of the photovoltaic battery pack and the energy storage system to supply power to the power grid or the load according to the control signal.

4. The control method according to claim 1 or 2, wherein the controller acquiring the control information includes:

the controller acquires the required power of the power grid or the load;

the controller acquires the power generation power of the photovoltaic battery pack;

wherein,

the controller controlling at least one of the photovoltaic battery pack and the energy storage system to supply power to the power grid or the load according to the control information comprises:

the controller controls at least one of the photovoltaic battery pack and the energy storage system to supply power to the power grid or the load according to the required power of the power grid or the load and the generated power of the photovoltaic battery pack.

5. The control method according to claim 4, wherein the power supply system further includes a current transformer CT,

wherein,

the controller acquiring the required power of the power grid or the load comprises: the controller receives the required power of the power grid or the load detected by the CT;

the controller acquiring the generated power of the photovoltaic battery pack comprises: and the controller receives the generated power of the photovoltaic battery pack obtained by the CT detection.

6. The control method according to claim 4 or 5, characterized in that the method further comprises:

and when the power of the photovoltaic cell is greater than the power required by the power grid or the load, controlling the second switch assembly to control the photovoltaic cell to charge an energy storage cell in the energy storage system.

7. The control method according to claim 4 or 5, characterized in that the method further comprises:

if the generated power of the photovoltaic cell is zero, the controller controls an energy storage cell in the energy storage system to supply power to the power grid or the load;

if the generated power of the photovoltaic cell is not zero and the power of the photovoltaic cell is less than the required power of the power grid or the load, the controller controls the photovoltaic cell group and the energy storage cell in the energy storage system to simultaneously supply power to the power grid or the load;

if the power of the photovoltaic cell is equal to the required power of the power grid or the load, the controller controls to disconnect the connection between the energy storage system and the photovoltaic inverter and controls the photovoltaic cell to supply power to the power grid or the load;

and if the power of the photovoltaic cell is larger than the required power of the power grid or the load, the controller controls the photovoltaic cell to supply power to the power grid or the load.

8. A power supply system, characterized in that the power supply system comprises: the photovoltaic battery pack comprises N photovoltaic batteries, wherein N is an integer greater than 1;

the photovoltaic battery pack is connected with a power grid or a load through the photovoltaic inverter;

the energy storage system is connected with the photovoltaic battery pack in parallel, and is connected with the power grid or the load through the photovoltaic inverter;

the controller is used for acquiring control information and controlling at least one of the photovoltaic battery pack and the energy storage system to supply power to the power grid or the load according to the control information.

9. The power supply system of claim 8 wherein the energy storage system comprises M energy storage cells and M bidirectional DC/DC, the M energy storage cells are connected in parallel, the M energy storage cells are in one-to-one correspondence with the M bidirectional DC/DC, M is a positive integer, each energy storage cell is connected to the photovoltaic cell bank through the bidirectional DC/DC, and each energy storage cell is further connected to the grid or the load through the photovoltaic inverter.

10. The power supply system according to claim 8 or 9, wherein the control information is a control signal, and the controller is configured to obtain the control information and control at least one of the photovoltaic battery pack and the energy storage system to supply power to the grid or the load according to the control information includes:

the controller receives a control signal and controls at least one of the photovoltaic battery pack and the energy storage system to supply power to the power grid or the load according to the control signal.

11. The power supply system according to claim 8 or 9, wherein the controller is further configured to obtain a required power of the grid or the load, obtain a generated power of the photovoltaic cell set, and control at least one of the photovoltaic cell set and the energy storage system to supply power to the grid or the load according to the required power of the grid or the load and the generated power of the photovoltaic cell set.

12. The power supply system of claim 11 further comprising a CT for detecting a power demand of the grid or the load, the CT further for detecting a power generated by the photovoltaic cell stack.

13. The power supply system of claim 11 or 12, wherein the controller is further configured to control the photovoltaic cell to charge an energy storage cell in the energy storage system when the power of the photovoltaic cell is greater than the power demand of the grid or the load.

14. The power supply system according to claim 11 or 12,

if the generated power of the photovoltaic battery pack is zero, the controller is used for controlling an energy storage battery in the energy storage system to supply power to the power grid or the load;

if the generated power of the photovoltaic battery pack is not zero and the power of the photovoltaic battery pack is less than the required power of the power grid or the load, the controller is used for controlling the photovoltaic battery pack and the energy storage battery in the energy storage system to simultaneously supply power to the power grid or the load;

if the generated power of the photovoltaic battery pack is equal to the required power of the power grid or the load, the controller is used for controlling to disconnect the connection between the energy storage system and the photovoltaic inverter and controlling the photovoltaic battery pack to supply power to the power grid or the load;

and if the generated power of the photovoltaic battery pack is greater than the required power of the power grid or the load, the controller is used for controlling the photovoltaic battery pack to supply power to the power grid or the load.