阅读说明：本技术 微电网海水淡化系统的负荷动态分配的装置及分配方法 (Device and method for dynamically distributing load of micro-grid seawater desalination system ) 是由 戴光标 许卫国 王福家 于 2021-08-10 设计创作，主要内容包括：本发明涉及一种微电网海水淡化系统的负荷动态分配的装置及分配方法,包括控制单元、储能单元及海水淡化设备；所述的控制单元通过modbus TCP/IP总线采集储能单元、海水淡化设备的信息,协调负荷动态分配以实现供电效率最大化运行；所述的海水淡化设备通过微电网产生的电能来淡化海水。该系统具备在不提升系统配置的前提下延长海水淡化设备的运行时间,提升产水量,能够有效地降低施工和日常维护管理的难度和费用,并保证了系统产水的稳定性和提高了装置的重复利用率,进而降低整个海水淡化系统的投资成本和提高海淡水在解决海岛居民用水问题中的角色地位。(The invention relates to a device and a method for dynamically distributing loads of a micro-grid seawater desalination system, wherein the device comprises a control unit, an energy storage unit and seawater desalination equipment; the control unit acquires information of the energy storage unit and the seawater desalination equipment through a modbus TCP/IP bus, coordinates dynamic load distribution and realizes maximum power supply efficiency operation; the seawater desalination equipment desalinates seawater by electric energy generated by a micro-grid. The system has the advantages that the running time of the seawater desalination equipment is prolonged on the premise that the system configuration is not improved, the water yield is improved, the difficulty and the cost of construction and daily maintenance management can be effectively reduced, the stability of water produced by the system is ensured, the repeated utilization rate of the device is improved, the investment cost of the whole seawater desalination system is reduced, and the role position of seawater and freshwater in solving the problem of water consumption of sea island residents is improved.)

1. The load dynamic distribution device of the microgrid seawater desalination system comprises a control unit, an energy storage unit and seawater desalination equipment; it is characterized in that:

the control unit acquires information of the energy storage unit and the seawater desalination equipment through a modbus TCP/IP bus, coordinates dynamic load distribution and realizes maximum power supply efficiency operation;

the seawater desalination equipment desalinates seawater by electric energy generated by a micro-grid.

2. The dynamic load distribution device of the microgrid seawater desalination system of claim 1, characterized in that: and the control unit is used for adjusting the dynamic distributed power balance of the load of the microgrid through the storage or release of the electric energy in the energy storage unit.

3. The dynamic load distribution device of the microgrid seawater desalination system of claim 1, characterized in that: the photovoltaic power generation unit is used for generating a photovoltaic power source and transmitting the generated photovoltaic power source to the energy storage unit through the photovoltaic charging controller.

4. The dynamic load distribution device of the microgrid seawater desalination system of claim 3, characterized in that: the inverter unit comprises a distributed power supply and a maximum power tracker connected with the distributed power supply; the intelligent direct current micro-grid system is used for providing electric energy for the intelligent direct current micro-grid system.

5. The dynamic load distribution device of the microgrid seawater desalination system of claim 1, characterized in that: the seawater desalination equipment is divided into a first-level load, a second-level load and a third-level load, is respectively connected with the execution unit, and is used for desalinating seawater through electric energy generated by the micro-grid to produce qualified fresh water.

6. The dynamic load distribution device of the microgrid seawater desalination system of claim 1, characterized in that: the energy storage unit comprises a storage battery energy storage device and a battery management system.

7. A distribution method of a load dynamic distribution device of a micro-grid seawater desalination system, comprising the load dynamic distribution device of the micro-grid seawater desalination system of any one of claims 1 to 6, characterized in that: when the dynamic load distribution device runs, the dynamic load distribution device dynamically adjusts the seawater desalination load and comprises the following steps:

step 1: the control unit acquires real-time running information of the photovoltaic charging controller, the inverter unit, the photovoltaic power generation unit, the control unit, the energy storage unit, the execution unit and the seawater desalination equipment through modbus TCP/IP bus communication; inputting the acquired illumination intensity through analog quantity, and acquiring date and time data through Beidou or GPS by using time synchronization software;

step 2: the control unit generates a prediction optimization instruction and a real-time optimization instruction, and transmits the prediction optimization instruction and the real-time optimization instruction to the photovoltaic charging controller, the inverter unit, the photovoltaic power generation unit, the control unit, the energy storage unit, the execution unit and the seawater desalination equipment through modbus TCP/IP bus communication;

and step 3: monitoring the SOC value of the residual capacity value of the energy storage battery through modbus bus communication to detect the power generation power of the photovoltaic system in real time;

and 4, step 4: judging whether to close the three-level load according to the illumination intensity, the SOC value and the illumination intensity value within a certain time;

and 5: judging whether to restart the third-level load or close the second-level load according to the illumination intensity, the SOC value and the illumination intensity value within a certain time;

step 6: judging whether the secondary load is turned on again or the primary load is turned off again according to the illumination intensity, the SOC value and the illumination intensity value within a certain time;

and 7: and judging to restart the first-level load or shut down the whole system according to the illumination intensity, the SOC value and the illumination intensity value within a certain time.

Technical Field

The invention relates to a new energy microgrid sea water desalination system, belongs to the field of microgrid sea water desalination, and particularly relates to a device and a method for dynamically distributing load of a photovoltaic new energy microgrid sea water desalination system.

Background

With the proposal of 'sea island seawater desalination engineering implementation scheme' printed by the union of the national development and improvement committee and the national oceanic administration in 12 months of 2017, the produced water of seawater desalination becomes one of the main water supply modes in water-deficient sea island regions in 2020. The embodiment clearly indicates that about 100 seawater desalination projects (the construction scale is 50-1000 m 3/d) are mainly constructed, upgraded and modified in coastal cities such as Liaoning, Shandong, Zhejiang, Fujian, Hainan and the like within 3-5 years, so that the water use problem of sea island residents is effectively reduced, and the continuously improved requirements on life and production water are met.

The problem of difficult water use of islands can be solved by combining seawater desalination and renewable energy sources aiming at the conditions of less fresh water consumption, less capital, less electric power and convenient seawater taking of islands. Compared with a large power grid, the micro power grid has natural advantages, the scale of the micro power grid is far smaller than that of the large power grid, the quantity of power supplies and loads is limited, and the grid structure is simple, so that the micro power grid is easy to monitor and control. The new energy micro-grid system provides stable electric energy for seawater desalination equipment and local residents by photovoltaic power generation and wind power generation and matching with an energy storage system and a battery system.

The new energy microgrid system has the advantages of high energy efficiency, low pollution and the like, but an energy storage system with a certain capacity needs to be equipped due to the characteristics of volatility, intermittence and the like of novel energy sources such as wind power generation and photovoltaic power generation, so that the effect of inhibiting fluctuation is exerted, and the stability of the microgrid system is enhanced to a certain extent. Generally, after a micro-grid is started, an energy storage battery needs to be charged by wind power generation or photovoltaic power generation, and after the residual capacity value of the battery in an energy storage system is larger than a set value, an operator combines time and observes illumination intensity to reach a certain degree, and then the micro-grid seawater desalination system is started to produce qualified drinking water or bottled water for local residents to drink. Due to weather reasons, after the electric equipment can only use the stored electric energy of the energy storage battery due to no light or breeze, the seawater desalination system is closed when the residual capacity value of the energy storage battery is smaller than a set value, and tripping or equipment damage caused by insufficient electric quantity is avoided.

Disclosure of Invention

In view of this, the present invention provides a load dynamic allocation apparatus of a micro-grid seawater desalination system and an allocation method thereof, and the technical scheme is as follows:

the load dynamic distribution device of the microgrid seawater desalination system comprises a control unit, an energy storage unit and seawater desalination equipment; it is characterized in that: the control unit acquires information of the energy storage unit and the seawater desalination equipment through a plurality of detection modules through a modbus TCP/IP bus, coordinates load dynamic distribution and realizes maximum operation of power supply efficiency; the seawater desalination equipment desalinates seawater by electric energy generated by a micro-grid.

Preferably: the control unit is also used for detecting the photovoltaic power generation unit and the inversion unit and sending the photovoltaic power generation unit and the inversion unit to the control unit through a micro-grid modbus TCP/IP bus; and the control unit optimization algorithm obtains a real-time control instruction and a prediction control instruction, and coordinates and schedules each unit to perform optimized operation.

Preferably: and the control unit is used for adjusting the dynamic distributed power balance of the load of the microgrid through the storage or release of the electric energy in the energy storage unit.

Preferably: the photovoltaic power generation unit is used for generating a photovoltaic power source and transmitting the generated photovoltaic power source to the energy storage unit through the photovoltaic charging controller.

Preferably: the inverter unit comprises a distributed power supply and a maximum power tracker connected with the distributed power supply; the intelligent direct current micro-grid system is used for providing electric energy for the intelligent direct current micro-grid system.

Preferably: the seawater desalination equipment is divided into a first-level load, a second-level load and a third-level load, is respectively connected with the execution unit, and is used for desalinating seawater through electric energy generated by the micro-grid to produce qualified fresh water.

Preferably: the energy storage unit comprises a storage battery energy storage device and a battery management system.

The invention also discloses a distribution method of the load dynamic distribution device of the micro-grid seawater desalination system, which is characterized by comprising the following steps: step 1: the control unit acquires real-time running information of the photovoltaic charging controller, the inverter unit, the photovoltaic power generation unit, the control unit, the energy storage unit, the execution unit and the seawater desalination equipment through modbus TCP/IP bus communication; inputting the acquired illumination intensity through analog quantity, and acquiring date and time data through Beidou or GPS by using time synchronization software;

step 2: the control unit generates a prediction optimization instruction and a real-time optimization instruction, and transmits the prediction optimization instruction and the real-time optimization instruction to the photovoltaic charging controller, the inverter unit, the photovoltaic power generation unit, the control unit, the energy storage unit, the execution unit and the seawater desalination equipment through modbus TCP/IP bus communication;

and step 3: monitoring a residual capacity value SOC value (SOC: battery charge state, also called residual capacity, which represents a ratio of residual dischargeable capacity to capacity in a full charge state after the battery is used for a period of time or is left unused for a long time, and is expressed by a common percentage) of the energy storage battery through modbus bus communication, and detecting the power generation power of the photovoltaic system in real time;

and 4, step 4: judging whether to close the three-level load according to the illumination intensity, the SOC value and the illumination intensity value within a certain time;

and 5: judging whether to restart the third-level load or close the second-level load according to the illumination intensity, the SOC value and the illumination intensity value within a certain time;

step 6: and judging to restart the secondary load or close the primary load according to the illumination intensity, the SOC value and the illumination intensity value within a certain time.

And 7: and judging to restart the first-level load or shut down the whole system according to the illumination intensity, the SOC value and the illumination intensity value within a certain time.

Advantageous effects

The device and the control system for dynamic load distribution of the new energy microgrid are provided for realizing dynamic load distribution, reducing the equipment shutdown times, reducing the energy consumption, improving the working time of seawater desalination equipment and improving the fresh water yield.

Drawings

FIG. 1 is a flow chart of the overall implementation of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments, and all other embodiments obtained by a person skilled in the art based on the embodiments of the present invention belong to the protection scope of the present invention without creative efforts.

The load dynamic distribution device of the microgrid seawater desalination system comprises a control unit, an energy storage unit and seawater desalination equipment; it is characterized in that: the control unit acquires information of the energy storage unit and the seawater desalination equipment through a plurality of detection modules through a modbus TCP/IP bus, coordinates load dynamic distribution and realizes maximum operation of power supply efficiency; the seawater desalination equipment desalinates seawater by electric energy generated by a micro-grid; the detection module is also used for detecting the photovoltaic power generation unit and the inversion unit and sending the photovoltaic power generation unit and the inversion unit to the control unit through a micro-grid modbus TCP/IP bus; the control unit optimization algorithm obtains a real-time control instruction and a prediction control instruction, and coordinates and schedules optimization operation of each unit; the control unit is used for storing or releasing electric energy in the energy storage unit to adjust the dynamic distributed power balance of the microgrid load; the photovoltaic power generation unit is used for generating a photovoltaic power source and transmitting the generated photovoltaic power source to the energy storage unit through the photovoltaic charging controller; the inverter unit comprises a distributed power supply and a maximum power tracker connected with the distributed power supply; the intelligent direct current micro-grid system is used for providing electric energy for the intelligent direct current micro-grid system; the seawater desalination equipment is divided into a first-level load, a second-level load and a third-level load, is respectively connected with the execution unit, and is used for desalinating seawater through electric energy generated by the micro-grid to produce qualified fresh water; the energy storage unit comprises a storage battery energy storage device and a battery management system;

the invention discloses a distribution method of a load dynamic distribution device of a micro-grid seawater desalination system, which is characterized by comprising the following steps: when the load dynamic distribution device runs, the seawater desalination load is dynamically adjusted; and comprises the following steps:

step 1: the control unit acquires real-time running information of the photovoltaic charging controller, the inverter unit, the photovoltaic power generation unit, the control unit, the energy storage unit, the execution unit and the seawater desalination equipment through modbus TCP/IP bus communication; inputting the acquired illumination intensity through analog quantity, and acquiring date and time data through Beidou or GPS by using time synchronization software;

step 2: the control unit generates a prediction optimization instruction and a real-time optimization instruction, and transmits the prediction optimization instruction and the real-time optimization instruction to the photovoltaic charging controller, the inverter unit, the photovoltaic power generation unit, the control unit, the energy storage unit, the execution unit and the seawater desalination equipment through modbus TCP/IP bus communication;

and step 3: monitoring a residual capacity value SOC value (SOC: battery charge state, also called residual capacity, which represents a ratio of residual dischargeable capacity to capacity in a full charge state after the battery is used for a period of time or is left unused for a long time, and is expressed by a common percentage) of the energy storage battery through modbus bus communication, and detecting the power generation power of the photovoltaic system in real time;

and 4, step 4: judging whether to close the three-level load according to the illumination intensity, the SOC value and the illumination intensity value within a certain time;

and 5: judging whether to restart the third-level load or close the second-level load according to the illumination intensity, the SOC value and the illumination intensity value within a certain time;

step 6: and judging to restart the secondary load or close the primary load according to the illumination intensity, the SOC value and the illumination intensity value within a certain time.

And 7: and judging to restart the first-level load or shut down the whole system according to the illumination intensity, the SOC value and the illumination intensity value within a certain time.

The steps are repeatedly executed, so that the intelligent direct current micro-grid system can continuously, reliably, efficiently and safely operate.

The implementation of the above steps 4-7 needs to be implemented according to the following algorithm:

defining the generated power P in the t hour_f (n) the power difference with the conventional load is the net power P of the microgrid_g (n)：

P_g(n) = P_f(n) -P_y(t) in the formula, P₁(t) the conventional load power of the microgrid at the tth hour;

and, when the net power P_f (n) is less than the lower limit of the sea water desalination load power P_y-min(n), i.e. P_f(n)＜P _yAnd (n), the control unit commands the execution unit to dynamically adjust the power loads of the first-level, second-level and third-level seawater desalination equipment, and the operation time of the whole equipment is prolonged:

at the moment, the load power P of seawater desalination_y(n)= P _y-s(n) discharge power P of the energy storage cell _b(n) = P _y-s(n) - P _g (n)；

Specifically, in the aspect of power distribution of the energy storage unit, the maximum dischargeable power is determined according to the rated capacity, the SOC state and the discharge depth of a converter of the energy storage unit;

after s1 minutes, if the net power Pf (n) is still less than the lower limit Py-s (n) of the seawater desalination load power, the control unit detects the liquid levels of the water production tanks of the first, second and third-level seawater desalination equipment and instructs the execution unit to preferentially close the third-level equipment in the seawater desalination equipment, at this time, the seawater desalination load power P y (n) = P y-s (n) -P y3(n), and the energy storage battery discharge power P b (n) = P y-s (n) - [ P g (n) -P y3(n) ];

if Pf (n) > P y-s (n), the control unit instructs the execution unit to recover the closed tertiary seawater desalination equipment.

After s2 minutes, if Pf (n) is more than P y-s (n), the control unit instructs the execution unit to recover the closed tertiary seawater desalination equipment. If the net power Pf (n) is still less than the lower limit Py-s (n) of the power of the seawater desalination load, the control unit detects the liquid level of a water production tank of the seawater desalination equipment and instructs the execution unit to shut down secondary equipment in the seawater desalination equipment preferentially, and at the moment, the power of the seawater desalination load is P y (n) = P y-s (n) -P y3(n) -P y2(n), and the discharge power of the energy storage battery is P b (n) = P y-s (n) - [ P g (n) -P y3(n) -P y2(n) ];

after s3 minutes, if Pf (n) > P y-s (n), the control unit instructs the execution unit to recover the closed secondary seawater desalination equipment. If the net power Pf (n) is still less than the lower limit Py-s (n) of the seawater desalination load power, the control unit detects the liquid level of a water production tank of the seawater desalination equipment and instructs the execution unit to preferentially close the primary equipment in the seawater desalination equipment, at the moment, the seawater desalination load power P y (n) =0, and the photovoltaic power generation unit is only used for charging the energy storage battery.

After s4 minutes, if the SOC value is larger than the set minimum starting-up value, the control unit commands the execution unit to start the closed primary seawater desalination equipment. If the SOC value is still smaller than the set minimum shutdown value, the control unit commands the execution unit to close the whole seawater desalination equipment, and the system stops running.

The steps are repeated, so that the intelligent direct current micro-grid system can continuously, reliably, efficiently and safely operate.

The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are merely illustrative of the principles of the invention, but that various changes and modifications may be made without departing from the spirit and scope of the invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.