JP7293482B1 - Balance control method for energy storage battery for photovoltaic power generation - Google Patents

Abstract

A balance control method for a photovoltaic energy storage battery is disclosed, which aims to solve the battery balance problem based on smoothing the output of photovoltaic power generation and prolong the service life of the battery. do. The method includes the steps of collecting a photovoltaic grid-connected power; determining a photovoltaic power output regulation based on the photovoltaic grid-connected power; comparing a photovoltaic output fluctuation rate with a preset threshold to obtain a first comparison result between the photovoltaic output fluctuation rate and the preset threshold; and charging a battery based on the first comparison result. and controlling the mode. [Selection drawing] Fig. 1

Description

TECHNICAL FIELD The present invention relates to the field of new energy, and in particular to a balance control method for a photovoltaic energy storage battery.

With the increase of photovoltaic power generation, adverse effects during use have gradually become apparent. In addition, as the restrictions on the use and diffusion of renewable energy due to factors such as large fluctuations in the power output of photovoltaic systems are becoming more severe, energy storage is deployed in grid-connected photovoltaic systems. It has become one of the current research directions of large-scale energy storage systems.

In the energy storage system arrangement method for the purpose of smoothing the photovoltaic power output, it is common to place a centralized energy storage system on the photovoltaic power generation side. A hybrid energy storage system has been proposed using the hybrid energy storage system, and furthermore, a control method for leveling the output power of wind power generation using it has been proposed. The proposed control method solves the shortcomings when the energy storage equipment is used alone to some extent, and can also balance the output power of the wind power system well, considering the demand of grid dispatch in the compensation process. .

However, in the conventional technology, the energy storage unit consisting of the storage battery pack and the supercapacitor in the hybrid energy storage system may cause the battery to overcharge or overdischarge due to manufacturing deviations, abnormalities in different charging and discharging conditions, etc. It did not take into account the problem of shortened service life.

Therefore, the technical problem to be solved by the present invention is to provide a balance control method for an energy storage battery for photovoltaic power generation in order to solve the problem of the prior art that the service life of the battery is shortened due to overcharge or overdischarge. is to provide

A balance control method for an energy storage battery for photovoltaic power generation provided by the present invention includes the steps of collecting grid-connected photovoltaic power, and determining a photovoltaic output fluctuation rate based on the grid-connected photovoltaic power. comparing the photovoltaic power output fluctuation rate with a preset threshold to obtain a first comparison result between the photovoltaic power output fluctuation rate and the preset threshold; based on the first comparison result and C. controlling the battery charging mode.

A balance control method for a photovoltaic energy storage battery provided in the present invention comprises the steps of obtaining energy storage enablement status information, photovoltaic output information, adjustable margin information, and current grid-connected power; determining an energy storage actual output value based on the energy storage enablement status information, the photovoltaic output information, the adjustable margin information, and the current grid-connected power; and the photovoltaic output fluctuation as a first comparison result. and adjusting the photovoltaic power output according to the energy storage actual output value if the rate is greater than or equal to a preset threshold.

Optionally, determining the energy storage actual output value based on the energy storage enablement state information, the solar power output information, the adjustable margin information, and the current grid-tied power comprises: determining a current energy storage output target value based on the solar power output information, if the energy storage cell is capable of enabling solar power output as information; and solar power output information and the current grid-tied power. determining a smoothing scheme of the energy storage cell for the photovoltaic output based on the current energy storage output target value and the adjustable margin information by the smoothing scheme for the energy storage cell for the photovoltaic output; and determining an energy storage actual output value.

Optionally, adjusting the photovoltaic power output according to the energy storage actual output value includes performing power smoothing on the photovoltaic power output according to the energy storage actual output value to reduce the photovoltaic power output power to the target output. including reaching power.

Optionally, the step of controlling the battery charging mode based on the first comparison result includes charging the battery with the generator if the photovoltaic output fluctuation rate is greater than or equal to a preset threshold as the first comparison result. and comparing the photovoltaic output power with the target output power when the photovoltaic output fluctuation rate is less than the preset threshold as a first comparison result, and comparing the photovoltaic output power with the target output power. obtaining two comparison results; and charging the battery with solar power or an engine based on the second comparison result.

Optionally, the step of determining a battery charging mode comprising charging the battery with solar power and/or an engine based on the second comparison result comprises: as the second comparison result, the solar power output power if it is larger than the electric power, comparing the solar power output reserve power amount with the battery cell replenishment power amount to obtain a third comparison result between the solar power generation output reserve power amount and the battery cell replenishment power amount; 3, based on the comparison result, determining that the battery charging mode is solar power or solar power and generator charging the battery; and as a second comparison result, the solar power output power is the target output power; and charging the battery with a generator if:

Optionally, charging the battery with a photovoltaic battery or photovoltaic and generator is collecting battery cell information including remaining capacity of the battery cell, the battery comprising a plurality of battery cells. a step of comparing the battery cell remaining amount with a preset remaining amount and determining whether the battery cell remaining amount is lower than the preset remaining amount; If it is lower than the remaining capacity, the step of calculating the required power amount for battery cell replenishment as the difference between the remaining battery cell capacity and the preset remaining capacity; charging the battery cells with photovoltaic power generation if the amount of power is greater than or equal to the required power amount; and the step of calculating the difference between the photovoltaic power generation output margin power amount and charging the battery cell with the photovoltaic power generation and the generator.

Optionally, charging the battery with the generator is collecting battery cell information including battery cell remaining capacity, wherein the battery comprises a plurality of battery cells and the battery cell remaining capacity is preset. determining whether or not the battery cell remaining amount is lower than the preset remaining amount by comparing with the obtained remaining amount, and if the battery cell remaining amount is lower than the preset remaining amount, the generator and charging the battery.

The present invention includes a memory and a processor, the memory and the processor are communicatively connected to each other, the memory is used to store a computer program, and the computer program is executed by the processor to achieve the performance of the present invention. A computing device is provided that causes a processor to execute the control method of any of the embodiments.

The present invention provides a computer readable storage medium for use in storing computer instructions that, when executed by a processor, implement the control method of any embodiment of the present invention.

In an embodiment of the present invention, the photovoltaic grid-connected power is collected, the photovoltaic output fluctuation rate is determined based on the photovoltaic grid-connected power, and the photovoltaic output fluctuation rate is set to a preset threshold value. to obtain a first comparison result between the photovoltaic power generation output fluctuation rate and a preset threshold value, and control the battery charging mode based on the first comparison result, so that the battery cell always has a constant remaining amount to solve the problem that the service life of the battery is shortened due to overcharging or overdischarging of the battery, and to extend the service life of the battery.

In order to describe the specific embodiments of the present invention or the technical solutions of the prior art more clearly, the following briefly describes the drawings that need to be used to describe the specific embodiments or the prior art. , Obviously, the drawings described below are some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without creative efforts can also
4 is a flow chart of a balance control method for a photovoltaic energy storage battery provided in an embodiment of the present invention; 4 is a flow chart of battery balance control provided in an embodiment of the present invention; 4 is a flow chart of smoothing control of photovoltaic output power provided in an embodiment of the present invention; Fig. 4 is a calculation flowchart for determining an energy storage actual output value provided in an embodiment of the present invention; 4 is a control flow chart for charging a battery with solar power provided in an embodiment of the present invention; Fig. 4 is a control flow chart for charging a battery with a solar power generator and a generator provided in an embodiment of the present invention; 4 is a control flow chart for charging a battery with a generator provided in an embodiment of the present invention; 1 is a schematic diagram of computer equipment provided in an embodiment of the present invention; FIG.

The following clearly and completely describes the technical solutions of the present invention with reference to the drawings, but obviously the described embodiments are some embodiments of the present invention, not all embodiments. All other embodiments that a person skilled in the art can obtain without creative efforts based on the embodiments of the present invention belong to the patent scope of the present invention.

The present embodiment provides a control method for solving battery balancing and solar power output smoothing, and as shown in FIG. 1, the method includes steps S1 to S4.

Step S1: collect the photovoltaic grid-connected power, the photovoltaic grid-connected power is the power when the transmission line of the generator unit is connected to the grid, and the photovoltaic power to be collected The grid-connected power includes the photovoltaic grid-connected power at the current time and the previous time.

Step S2: Determine the photovoltaic power generation output fluctuation rate based on the photovoltaic power generation grid-connected power, and calculate the difference in the grid-connected power at two adjacent sampling times and the photovoltaic power generation rated installed capacity. Obtain the photovoltaic output regulation. The formula is as follows.

In the above formula, δ is the photovoltaic power generation output fluctuation rate, _ΔPPV is the difference in the photovoltaic power generation grid-connected power at two adjacent sampling times, and _ΔPPV-N is the photovoltaic power generation rated installed capacity.

Step S3: Compare the photovoltaic output fluctuation rate with a preset threshold to obtain a first comparison result between the photovoltaic output fluctuation rate and the preset threshold.

Step S4: Control the battery charging mode according to the first comparison result, and if the first comparison result shows that the photovoltaic output fluctuation rate is equal to or greater than the preset threshold, charge the battery with the generator and perform the first comparison. As a result, if the photovoltaic power output fluctuation rate is less than the preset threshold, comparing the photovoltaic power output power with the target output power to obtain a second comparison result between the photovoltaic power output power and the target output power.

If the second comparison result is that the photovoltaic output power is less than or equal to the target output power, the battery is charged by the generator, and if the second comparison result is that the photovoltaic output power is greater than the target output power, the photovoltaic power output The surplus power amount ΔP _PV-E is compared with the required power amount for replenishment of the battery cell, which is the difference _ΔPS-E between the current remaining amount of the battery cell and the preset remaining amount, and the solar power generation output margin power is calculated. A third comparison result is obtained between the amount ΔP _PV-E and the required power amount ΔP _SE for replenishment of the battery cell, and based on the third comparison result, the battery is charged with solar power generation or with solar power generation. Determine whether to charge the battery with a generator.

If the third comparison result shows that the solar power output margin power amount is greater than or equal to the power amount required to replenish the battery cell remaining amount (ΔP _PV-E ≧ΔP _SE ), the battery cell is charged by solar power generation.

As a result of the third comparison, when the solar power generation output margin power amount is less than the battery cell remaining amount replenishment required power amount (ΔP _PV-E < ΔP _SE ), the battery cell replenishment required power amount and the photovoltaic power generation output Calculate the difference from the surplus electric energy, and charge the battery cells with solar power generation and generator.

In the above balance control method of energy storage battery for photovoltaic power generation, by charging the battery with photovoltaic power generation and generator, the problem of uneven energy distribution among the energy storage cells is solved, and the battery is Extend the service life of the battery, improve the quality of electricity generated by solar power, save energy, improve the ability to consume and supply solar power, and the specific flow chart of battery balance control is shown in Fig. 2. show.

Preferably, in step S3, if the photovoltaic output fluctuation rate is greater than or equal to a preset threshold as the first comparison result, the result includes smoothing the photovoltaic output power according to the energy storage actual output value. , further includes making the photovoltaic output power reach the target output power, and the specific control flow for smoothing the photovoltaic output power is shown in FIG.

Specifically, power smoothing is performed on the photovoltaic power output according to the energy storage actual output value, and the photovoltaic power output power reaches the target output power. obtaining information, adjustable margin information, and current grid-tied power; Determining a storage actual output value, and the controller transmitting the energy storage actual output value to an Energy Management System (EMS), the EMS performing power smoothing on the photovoltaic output to obtain a target output power value. including reaching

Specifically, determining the energy storage actual output value based on the energy storage enablement state information, the photovoltaic power output information, the adjustable margin information, and the current grid-connected power includes: Based on the information, determine whether the energy storage cell is capable of enabling solar power output; if so, smooth the solar power output at the energy storage cell; , not performing a solar power generation smoothing operation, and calculating a current energy storage output target value based on the solar power generation output information. A maximum charge effective value or a maximum discharge effective value is obtained based on the adjustable margin information. First, if the energy storage cell can smooth the photovoltaic power generation, combined with the photovoltaic power output information, adopt the low-pass filtering algorithm to calculate the current energy storage output target value, that is, adopt the low-pass filtering algorithm. to decompose the current photovoltaic grid-connected power and the current energy storage output target value; If the PV output power of is greater than the current PV grid-tied power, the energy storage cells will be charged with the current PV output margin power (smoothing the PV output by charging the energy storage cells). at this time, further determine the magnitude of the current energy storage output target value and the maximum charging effective value, if the current energy storage output target value>maximum charging effective value, If the energy storage actual output value is equal to the maximum charge effective value and the current energy storage output target value < the maximum charge effective value, then the energy storage actual output value is equal to the current energy storage output target value and the current solar power output If the power is less than the current PV grid-tied power, the energy storage cell is discharged to compensate for the difference between the current PV grid-tied power and the current PV output power (Energy storage cell (equivalent to smoothing the photovoltaic power output by discharging ), at this time, the magnitudes of the current energy storage output target value and the maximum discharge effective value are further determined, and the current energy storage output target value > maximum if the discharge effective value, the energy storage actual output value is equal to the maximum discharge effective value, and if the current energy storage output target value < the maximum discharge effective value, then the energy storage actual output value is equal to the current energy storage output target value; The process of determining the energy storage actual output value is specifically shown in FIG. system requirements, thereby reducing fluctuations due to PV grid interconnection.

Preferably, in step S4, charging the battery cells with solar power includes collecting battery cell information; and if the battery cell remaining amount is lower than the preset remaining amount, battery cell refilling is performed as the difference between the battery cell remaining amount and the preset remaining amount. Calculating the required amount of power, comparing the solar power generation output margin power amount _ΔPPV-E with the battery cell replenishment necessary power amount ΔPS _-E , and calculating the solar power generation output margin power amount _ΔPPV-E A third comparison result is obtained with the amount of electric power required to replenish the battery cell _ΔPSE , and based on the third comparison result, the switching circuit is controlled to charge the battery with solar power generation, or solar power generation and power generation determining whether the battery is to be charged by the machine, and as a result of the third comparison, if the solar power generation output margin power amount is greater than or equal to the battery cell replenishment power amount (ΔP _PV-E ≧ΔP _S-E ), charging the battery cells with photovoltaic power, and if the remaining battery level is greater than or equal to a preset remaining capacity, the controller controls the switching circuit to end charging the battery cells; A specific control flow for charging the battery is shown in FIG.

Preferably, in step S4, charging the battery cells with photovoltaic power generation and generator includes collecting battery cell information, comparing the battery cell remaining capacity with a preset remaining capacity, and determining the battery cell remaining capacity. is lower than the preset remaining amount, and if the battery cell remaining amount is lower than the preset remaining amount, the difference between the battery cell remaining amount and the preset remaining amount is Calculating the required power amount for battery cell replenishment, and comparing the solar power output margin power amount ΔP _PV-E with the battery cell replenishment power amount ΔP _SE to obtain the solar power power output margin power amount _ΔPPV A third comparison result is obtained between _-E and the required electric energy for battery cell replenishment _ΔPS-E , and based on the third comparison result, the switching circuit is controlled to charge the battery with solar power or sunlight. Judging whether to charge the battery with power generation and generator, and as a third comparison result, if the solar power generation output margin power amount is less than the battery cell replenishment required power amount (ΔP _PV-E < ΔP _S-E ) If there is, calculate the difference between the amount of power required to replenish the battery cell and the amount of solar power generation output margin power, charge the battery cell with the solar power generation and the generator, and the remaining battery level is greater than or equal to the preset remaining amount. In this case, the controller controls the switching circuit to terminate the charging of the battery cells, and the specific control flow of charging the battery with solar power and generator is shown in FIG.

Preferably, in step S4, charging the battery with the generator includes collecting information on the battery cell, which is a battery unit, and comparing the remaining battery cell level with a preset remaining capacity to determine the remaining battery cell level. is lower than the preset remaining amount, and if the battery cell remaining amount is lower than the preset remaining amount, the controller controls the switching circuit to charge the battery with the generator. , when the remaining battery capacity is greater than or equal to the preset remaining capacity, the controller controls the switching circuit to terminate the charging of the battery cells, and the specific control flow of charging the battery with the generator. It is shown in FIG.

This embodiment provides a computer device, which includes at least one processor 41, at least one communication interface 42, at least one communication bus 43, and at least one memory 44, as shown in FIG. Among these, the communication interface 42 may include a display, a keyboard, and the communication interface 42 may optionally include a standard wired interface and a wireless interface. Memory 44 may be high speed RAM memory (Random Access Memory) or may be non-volatile memory, such as at least one magnetic disk memory. Memory 44 may optionally be at least one storage device separate from processor 41 described above. The processor 41 may be combined with the apparatus described in FIG. 8, and an application program is stored in the memory 44, the processor 41 calling the program code stored in the memory 44 to generate the sunlight in any of the method embodiments described above. It is used to carry out the steps of balancing control of the energy storage battery for power generation.

Communication bus 43 may be a peripheral component interconnect (PCI for short) bus or an extended industry standard architecture (EISA for short) bus, or the like. Communication bus 43 may be divided into an address bus, a data bus, a control bus, and the like. For ease of explanation, only one thick line is shown in FIG. 8, but that does not mean that there is only one bus or one type of bus.

The memory 44 may include volatile memory, such as random-access memory (abbreviation: RAM), and non-volatile memory, such as flash. It may comprise a memory (English: flash memory), a hard disk (English: hard disk drive, abbreviation: HDD) or a solid-state hard disk (English: solid-state drive, abbreviation: SSD), or it may comprise a combination of the above types of memory. good.

The processor 41 may be a central processing unit (English: central processing unit, abbreviation: CPU), a network processor (English: network processor, abbreviation: NP) or a combination of CPU and NP.

Processor 41 may further include hardware chips. The hardware chip may be an application-specific integrated circuit (abbreviation: ASIC), a programmable logic device (abbreviation: PLD) or a combination thereof. The above PLD is a complex programmable logic device (English: complex programmable logic device, abbreviation: CPLD), field programmable gate array (English: field-programmable gate array, abbreviation: FPGA), generic array logic (English: generic arraylogic , abbreviation: GAL) or any combination thereof. Optionally, memory 44 is also used to store program instructions. The processor 41 may invoke program instructions to implement the balance control method for a photovoltaic energy storage battery according to any embodiment of the present invention.

The present embodiments provide a computer-readable storage medium having computer-executable instructions stored thereon, the computer-executable instructions for performing energy storage for photovoltaic generation in any of the above method embodiments. A battery balance control method can be implemented. Storage media include magnetic disk, compact disk, read-only memory (ROM), random access memory (RAM), flash memory, hard disk drive (abbreviation: HDD) ) or a Solid-State Drive (SSD), etc., and the storage medium may further comprise a combination of the above types of memory.

Of course, the above examples are merely illustrative for clarity of explanation and are not intended to limit the embodiments. Persons skilled in the art may make various other changes and modifications based on the above description. It is neither necessary nor possible to cover all embodiments here. Obvious variations and modifications derived from the foregoing are intended to be included within the patentable scope of the present invention.

Claims (7)

A balance control method for an energy storage battery for photovoltaic power generation, comprising:
collecting photovoltaic grid-tied power;
determining a photovoltaic output fluctuation rate based on the photovoltaic grid-connected power;
comparing the photovoltaic power output fluctuation rate with a preset threshold to obtain a first comparison result between the photovoltaic power output fluctuation rate and the preset threshold;
controlling a battery charging mode based on the first comparison result;
The step of controlling a battery charging mode based on the first comparison result comprises:
charging a battery with a generator when the photovoltaic output fluctuation rate is equal to or greater than the preset threshold value as the first comparison result;
When the photovoltaic power generation output fluctuation rate is less than the preset threshold value as the first comparison result, the photovoltaic power generation output power is compared with the target output power, and the photovoltaic power generation output power and the target output power are compared. 2 obtaining a comparison result;
determining a battery charging mode including charging the battery with solar power and/or an engine based on the second comparison result;
The step of determining a battery charging mode based on the second comparison result comprises:
If the second comparison result is that the photovoltaic output power is greater than the target output power, the photovoltaic power generation output margin power amount is compared with the battery cell replenishment required power amount, and the photovoltaic power generation output margin power amount and the battery cell replenishment power amount are compared. obtaining a third comparison result with the power requirement;
determining, based on the third comparison result, that the battery charging mode is charging the battery with solar power or solar power and a generator;
determining that the battery charging mode is to charge the battery with a generator if the second comparison result is that the photovoltaic output power is less than or equal to the target output power;
The step of charging the battery with solar power or solar power and a generator comprises:
the battery includes a plurality of battery cells, and collecting battery cell information including remaining capacity of the battery cells;
comparing the remaining battery cell level with a preset remaining level, and determining whether the remaining battery cell level is lower than the preset remaining level;
if the remaining battery cell amount is lower than the preset remaining amount, calculating a required amount of power for supplementing the battery cell as a difference between the remaining battery cell amount and the preset remaining amount;
charging the battery cell with photovoltaic power generation when the third comparison result shows that the surplus power output from the photovoltaic power generation is equal to or greater than the required power amount for replenishment of the battery cell;
If the third comparison result shows that the solar power generation output margin power amount is less than the battery cell replenishment necessary power amount, the difference between the battery cell replenishment necessary power amount and the solar power generation output margin power amount is calculated. and charging the battery cells with a photovoltaic generator and a generator. obtaining energy storage enablement status information, solar power output information, adjustable margin information, current grid-tied power;
determining an energy storage actual output value based on the energy storage enablement status information, the solar power output information, the adjustable margin information, and the current grid-tied power;
adjusting the photovoltaic power output according to the energy storage actual output value when the photovoltaic power output fluctuation rate is greater than or equal to a preset threshold value as the first comparison result. The control method according to claim 1. The step of determining an energy storage actual output value based on the energy storage enablement state information, the solar power output information, the adjustable margin information, and the current grid-tied power, wherein
determining a current energy storage output target value based on the solar power output information if the energy storage cell is capable of enabling solar power output as the energy storage enablement status information;
determining a smoothing scheme of the energy storage cell for solar power output based on the solar power output information and the current grid-tied power;
determining an energy storage actual output value based on the current energy storage output target value and adjustable margin information by a smoothing scheme of the energy storage cell to the photovoltaic output. The control method according to claim 2. The step of adjusting the photovoltaic power output according to the energy storage actual output value comprises:
3. The control method according to claim 2, further comprising performing power smoothing on the photovoltaic power output according to the energy storage actual output value to make the photovoltaic power output power reach a target output power. The step of charging the battery with a generator comprises:
collecting battery cell information including remaining battery cell capacity, wherein a battery includes a plurality of said battery cells;
comparing the remaining battery cell level with a preset remaining level, and determining whether the remaining battery cell level is lower than the preset remaining level;
2. The control method of claim 1, comprising charging a battery with a generator when the battery cell remaining capacity is lower than the preset remaining capacity. a memory and a processor, wherein the memory and the processor are communicatively coupled to each other;
The memory is used for storing a computer program, and when the computer program is executed by the processor, it causes the processor to execute the control method according to any one of claims 1 to 5. computer equipment. A computer readable storage medium, characterized in that it is used to store computer instructions which, when executed by a processor, implement the control method according to any one of claims 1 to 5.

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