CN113690878A

CN113690878A - Micro-grid three-switch control method

Info

Publication number: CN113690878A
Application number: CN202110885891.3A
Authority: CN
Inventors: 谢正和; 梁浩; 郭强; 孟超; 梅东升; 毛永清; 蔡来生; 冯宝泉
Original assignee: Beijing Jingneng Energy Technology Research Co ltd
Current assignee: Beijing Jingneng Energy Technology Research Co ltd
Priority date: 2021-08-03
Filing date: 2021-08-03
Publication date: 2021-11-23
Anticipated expiration: 2041-08-03
Also published as: CN113690878B

Abstract

The embodiment of the invention provides a microgrid trisection control method, which is characterized in that the generated energy of a photovoltaic power generation device is predicted, the load power consumption of each transformer is predicted, and the photovoltaic power generation device is switched to different transformer sides according to the prediction result, so that the aim of maximizing local consumption of new energy is fulfilled, and the benefit maximization is realized; meanwhile, the energy storage device is charged during the valley time electricity price period, and the energy storage device is switched to different transformers and set to discharge according to the predicted load electricity consumption and the actual electricity price of each transformer during the peak time electricity price period, so that the power fluctuation caused by the peak and valley power demand is stabilized, the opportunity cost for charging the energy storage device is minimized, and the benefit maximization is further realized.

Description

Micro-grid three-switch control method

Technical Field

The invention relates to the field of new and old kinetic energy conversion of power supply and distribution systems, in particular to a microgrid three-switch control method.

Background

Under the background of new energy, new technology, new traffic and new trend, energy transformation and low-carbon development become the era main melody, and a power plant is a great trend to respond to the national green development call as the important support and foundation of the traditional power system. Distributed power generation is a system in which a power generation system is arranged near users in a small-scale, decentralized manner and can independently output electric energy. The distributed power generation system has the advantages of energy conservation and emission reduction, low loss, high efficiency and the like, and distributed power generation has various problems, such as influence on the operation safety of a power grid, long cost recovery time, unstable power generation yield and the like.

In the process of implementing the invention, the applicant finds that at least the following problems exist in the prior art:

the electric power obtained by photovoltaic power generation cannot be fully and effectively utilized, so that the benefit maximization of new energy cannot be achieved.

Disclosure of Invention

The embodiment of the invention provides a microgrid three-switch control method, which solves the problems of fully utilizing new energy and power supply of a traditional power system and improving the use benefit of the new energy.

To achieve the above object, in one aspect, an embodiment of the present invention provides a microgrid trisection control method, including: the method comprises the following steps of a mains supply transformer, N plant power transformers, a photovoltaic power generation device and an energy storage device, wherein the method comprises the following steps:

predicting the power consumption of the commercial power transformer in a specified first time period to obtain the predicted load power consumption of the commercial power;

predicting the power consumption of the N power transformers within the first time period to obtain the power consumption of the power transformer power prediction load of each power transformer;

predicting the photovoltaic power generation amount of the photovoltaic power generation device in the first time period to obtain photovoltaic predicted power generation amount;

if the photovoltaic prediction power generation amount is smaller than or equal to the electric supply prediction load power consumption amount, setting a transformer selected to be switched in by the photovoltaic power generation device as the electric supply transformer;

if the photovoltaic prediction power generation amount is larger than the commercial power prediction load power consumption, setting the transformer selected by the photovoltaic power generation device to be the plant power transformer with the largest plant power prediction load power consumption value in the N plant power transformers;

if the current actual electricity price of the mains supply transformer is the electricity price at the valley time, setting the transformer selected to be switched in by the energy storage device as the mains supply transformer and setting the energy storage device as a charging state;

if the current actual electricity price of the commercial power transformer is the peak-hour electricity price, setting the transformer selected to be switched in by the energy storage device and setting the energy storage device to be in a discharge state according to the predicted load electricity consumption of the commercial power and the predicted load electricity consumption of the respective plant electricity of the N plant electricity transformers;

wherein N is a positive integer greater than or equal to 1.

Further, after the step of setting the transformer selected to be switched in by the photovoltaic power generation device as the utility power transformer if the photovoltaic prediction power generation amount is less than or equal to the utility power prediction load power consumption amount, the method further includes:

if the actual generating capacity of the photovoltaic generating device is less than or equal to the actual load power consumption of the commercial power transformer, setting the running state of the photovoltaic generating device to be a full-power generating state; and otherwise, the residual electric quantity of the photovoltaic power generation device is uploaded to a public power grid.

Further, after the step of setting the transformer selected to be switched in by the photovoltaic power generation device as the plant power transformer with the largest plant power predicted load power consumption value in the N plant power transformers if the photovoltaic predicted power generation amount is larger than the utility power predicted load power consumption, the method further comprises the following steps:

and setting the running state of the photovoltaic power generation device to be a full-power generation state.

Further, predicting the power consumption of the utility power transformer in a specified first time period to obtain the power consumption of the utility power prediction load, specifically includes:

the method comprises the steps of collecting power consumption of a mains supply transformer in a first appointed historical time period, establishing a mains supply predicted load curve according to the collected power consumption of the mains supply transformer, and obtaining the mains supply predicted load power consumption in the first time period according to the mains supply predicted load curve.

Further, predicting the power consumption of the N power transformers in the first time period to obtain the power consumption of the power transformer prediction load, specifically including:

and respectively collecting the power consumption of the N power transformers within a specified second historical time period, respectively establishing power plant prediction load curves corresponding to the power transformers according to the collected power consumption of the power transformers, and obtaining the power plant prediction load power consumption of the power transformers within the first time period according to the power plant prediction load curves.

Further, the setting of the transformer selected to be switched in by the energy storage device and the setting of the energy storage device to be in a discharge state according to the utility power prediction load power consumption and the respective plant power prediction load power consumption of the N plant power transformers includes:

predicting the discharge capacity of the energy storage device to obtain the energy storage predicted discharge capacity;

if the energy storage prediction discharge capacity is larger than the commercial power prediction load power consumption, the energy storage device selects the switched-in transformer to be set as the plant power transformer with the largest plant power prediction load power consumption numerical value in the N plant power transformers, the energy storage device is set to discharge according to the plant power prediction load curve corresponding to the plant power transformer switched in by the energy storage device, and otherwise, the energy storage device is switched into the commercial power transformer and is set to discharge to the commercial power transformer according to the commercial power prediction load curve.

Further, the N plant transformers include: a first plant transformer and a second plant transformer; wherein N is 2;

the microgrid also comprises: the first third power supply switching cabinet and the second third power supply switching cabinet;

the photovoltaic power generation device is electrically connected with one or more of a mains supply transformer, a first plant transformer or a second plant transformer through the first third power supply switching cabinet;

the energy storage device is electrically connected with one or more of a mains supply transformer, a first plant power transformer or a second plant power transformer through the second third power supply switching cabinet;

the transformer that will photovoltaic power generation device selection is cut into sets up as commercial power transformer specifically is:

controlling the first third power switching cabinet to electrically connect the photovoltaic power generation device to the mains transformer;

the method is characterized in that the transformer selected to be switched in by the photovoltaic power generation device is set as the plant power transformer with the largest plant power prediction load power consumption value in the N plant power transformers, and specifically comprises the following steps:

controlling the first third power supply switch cabinet to electrically connect the photovoltaic power generation device with the plant power transformer with the largest plant power prediction load power consumption value in the first plant power transformer and the second plant power transformer;

the transformer selected to be switched in by the energy storage device is set as the mains supply transformer, and the method specifically comprises the following steps:

controlling the second third power switching cabinet to electrically connect the energy storage device to the mains transformer;

the method comprises the following steps of setting the transformers selected to be switched in by the energy storage device according to the electric supply forecast load power consumption and the respective plant electricity forecast load power consumption of the N plant electricity transformers, and specifically comprises the following steps:

and controlling a second third power supply switching cabinet to electrically connect the energy storage device to one of the first plant power transformer and the second plant power transformer according to the utility power predicted load power consumption, the plant power predicted load power consumption of the first plant power transformer and the plant power predicted load power consumption of the second plant power transformer.

The technical scheme has the following beneficial effects: the purpose of maximizing local consumption of new energy is achieved by predicting the generated energy of the photovoltaic power generation device, predicting the load power consumption of each transformer and switching the photovoltaic power generation device to different transformer sides according to the prediction result, so that the benefit maximization is realized; meanwhile, the energy storage device is charged during the valley time electricity price period, and the energy storage device is switched to different transformers and set to discharge according to the predicted load electricity consumption and the actual electricity price of each transformer during the peak time electricity price period, so that the power fluctuation caused by the peak and valley power demand is stabilized, the opportunity cost for charging the energy storage device is minimized, and the benefit maximization is further realized.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a flowchart of a microgrid trisection control method according to one embodiment of the present invention;

FIG. 2 is a schematic diagram of an architecture of a microgrid according to one embodiment of the present invention;

fig. 3 is another flowchart of a microgrid trisection control method according to one embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the 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, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

On one hand, as shown in fig. 1, an embodiment of the present invention provides a microgrid trisection control method, where the method is applied to a microgrid control device, where the microgrid control device may be any terminal or server having a computing function, and the microgrid includes: the method comprises the following steps of:

s100, predicting the power consumption of the commercial power transformer in a specified first time period to obtain the predicted load power consumption of the commercial power;

in one embodiment, the utility transformer refers to a transformer for supplying power to a local area or a transformer for supplying power to an area where the photovoltaic power generation device is located or a nearby area; for example, the area served by the utility transformer may be one or several residential areas, and at the same time, photovoltaic power generation devices are arranged in or near the residential areas; the area served by the mains transformer can also be the area where one or more factories are located, and meanwhile, photovoltaic power generation devices are arranged in or near the factories; the utility transformer may also refer to a transformer that performs peak-to-valley electricity rates, such as a transformer that may use electricity including, but not limited to, residential electricity that performs peak-to-valley electricity rates and factory electricity that performs peak-to-valley electricity rates; the first time period specified may be a daily period, with predictions for each day, or may be a multiple of days or longer or shorter time intervals as a prediction and control period, as may be determined by the needs of a particular practice. The prediction of the power consumption of the transformer load can be carried out by various optional methods including but not limited to a neural network method, a wavelet analysis prediction technology, a time series method, a regression analysis method and the like, and the prediction results of various methods can be further analyzed and calculated to obtain more accurate prediction.

S101, predicting the power consumption of the N power transformers within the first time period to obtain the power consumption of the power prediction load of each power transformer;

in one embodiment, some or all of the N plant transformers may be transformers for supplying power to a local area, and some or all of the transformers may also be transformers for supplying power to a vicinity of the local area; part or all of the transformers can also be transformers for supplying power to residents or transformers for supplying power to factories; some or all of the transformers may be transformers that perform peak-to-valley electricity rates or may be transformers that perform one port rate.

S102, predicting the photovoltaic power generation amount of the photovoltaic power generation device in the first time period to obtain photovoltaic predicted power generation amount;

in one embodiment, the utility power predicted load electricity usage, the plant electricity predicted load electricity usage of the N plant electricity transformers, and the photovoltaic predicted power generation of the photovoltaic power generation device are predicted within the same designated first time period. The person skilled in the art can obtain a prediction method for the power generation amount of the photovoltaic power generation device through the public data, and the person skilled in the art can design the prediction method according to the influence factors of the photovoltaic power generation.

S103, if the photovoltaic prediction power generation amount is smaller than or equal to the electric supply prediction load power consumption amount, setting a transformer selected to be switched in by the photovoltaic power generation device as the electric supply transformer;

in one embodiment, when it is predicted that the power generation amount of the photovoltaic power generation device in the current period, for example, in the current day, is less than or equal to the predicted load power consumption amount of the commercial power, that is, the power generated by the photovoltaic power generation device can be consumed in the local area, the photovoltaic power generation device is set to switch into the commercial power transformer to supply power to the local area.

S104, if the photovoltaic prediction power generation amount is larger than the commercial power prediction load power consumption amount, setting the transformer selected by the photovoltaic power generation device to be a plant power transformer with the largest plant power prediction load power consumption amount value in the N plant power transformers;

in one embodiment, when the photovoltaic power generation amount is predicted to be larger than the commercial power predicted load power consumption amount of the local area, the power generation amount of the photovoltaic power generation device cannot be completely consumed in the local area, and the photovoltaic power generation device is switched into one plant power transformer with the largest plant power predicted load power consumption amount value in the N plant power transformers so as to fully consume the power generated by the photovoltaic power generation device.

S105, if the current actual electricity price of the mains supply transformer is the electricity price at the valley time, setting the transformer selected to be switched in by the energy storage device as the mains supply transformer and setting the energy storage device in a charging state;

in one embodiment, when the actual electricity price of the local mains supply transformer is at the valley time electricity price, the energy storage device is switched into the mains supply transformer, and the power of the mains supply transformer is used for charging the energy storage device, so that the opportunity cost of charging is reduced. In general, during the off-peak electricity price period, the power demand is low, and at this time, the energy storage device can be used for storing the redundant power, so that the energy storage device outputs the power outwards during the peak electricity price period, and the expansion benefit of smoothing the power fluctuation and maximizing the power fluctuation can be realized.

S106, if the current actual electricity price of the mains supply transformer is the peak-hour electricity price, setting the transformer selected to be switched in by the energy storage device and setting the energy storage device to be in a discharging state according to the predicted load electricity consumption of the mains supply and the predicted load electricity consumption of the respective plant electricity of the N plant electricity transformers;

in one embodiment, when the actual electricity price of the electric power output by the local commercial power transformer is the peak-time electricity price, different transformers can be selected to be switched in during energy storage and discharge according to the predicted load electricity consumption and the real-time electricity price conditions of the different transformers, so that the energy storage benefit is maximized.

Wherein N is a positive integer greater than or equal to 1.

In one embodiment, N is preferably 2, i.e. the two plant transformers comprise a first plant transformer and a second plant transformer; for example, the first plant electrical transformer may be a 2500kVA transformer, and the second plant electrical transformer may be a 630kVA transformer; the mains transformer may be a 1250kVA transformer; the specified first time period is preferably one day; preferably, the utility power transformer is peak valley electricity price, and the N power transformers are one port electricity price. When the predicted photovoltaic power generation amount is smaller than or equal to the predicted commercial power load power consumption of the commercial power transformer, the photovoltaic power generation device is switched into the commercial power transformer of 1250kVA for absorption on the same day; when the predicted photovoltaic power generation amount is larger than the predicted commercial power load power consumption of the commercial power transformer, which indicates that the power generated by the photovoltaic power generation device cannot be completely absorbed by the load under the commercial power transformer, the photovoltaic power generation device is switched to the plant power transformer to be absorbed on the same day; according to the load prediction of the 630kVA life transformer (namely, the second plant electric transformer) and the 2500kVA transformer (namely, the first plant electric transformer), the photovoltaic power generation device is preferentially switched to the one with larger power consumption of the plant electric prediction load of the first plant electric transformer and the second plant electric transformer for consumption. The energy storage device is implemented according to a daily 'one charge and one discharge' strategy, and because the 1250kVA transformer (namely a mains supply transformer) side is at the peak-valley electricity price, the low-valley electricity price at night (namely the off-valley electricity price) is lower; therefore, during the valley time electricity price period, the energy storage device is switched into the mains supply transformer, and the time period of energy storage charging is ensured to be on the mains supply side. According to the load size and the real-time electricity price condition predicted by different transformers, different transformers are selected to be switched in when the energy storage device discharges, and the energy storage benefit maximization is achieved.

The embodiment of the invention has the following technical effects: the purpose of maximizing local consumption of new energy is achieved by predicting the generated energy of the photovoltaic power generation device, predicting the load power consumption of each transformer and switching the photovoltaic power generation device to different transformer sides according to the prediction result, so that the benefit maximization is realized; meanwhile, the energy storage device is charged during the valley time electricity price period, and the energy storage device is switched to different transformers and set to discharge according to the predicted load electricity consumption and the actual electricity price of each transformer during the peak time electricity price period, so that the power fluctuation caused by the peak and valley power demand is stabilized, the opportunity cost for charging the energy storage device is minimized, and the benefit maximization is further realized.

In one embodiment, the predicted values of the photovoltaic predicted power generation amount and the commercial power predicted load power consumption amount may have respective deviations, so that after the photovoltaic power generation device is switched into the commercial power transformer side, the actual power generation amount of the photovoltaic power generation device is found to be less than or equal to the actual load power consumption amount of the commercial power transformer in the actual operation process, and at the moment, the photovoltaic power generation device is set to be in a full-power generation state, so that the photovoltaic power generation device can be fully utilized to supply power to the commercial power transformer side; when the actual generating capacity of the photovoltaic power generation device is larger than the actual load power consumption of the commercial power transformer, at the moment, the power generated by the photovoltaic power generation device cannot be completely consumed by the commercial power transformer side, and in order to avoid waste of the power, the residual power of the photovoltaic power generation device is transmitted to a public power grid, so that new energy is utilized to the maximum extent.

The embodiment of the invention has the following technical effects: according to the relation between the actual power consumption of the photovoltaic power generation device and the actual power consumption of the commercial power transformer, the power generated by the photovoltaic power generation device is fully utilized, and the maximum utilization of new energy is realized.

In one embodiment, when the generated energy of the photovoltaic power generation device at the current day is predicted not to be completely consumed on the side of the commercial power transformer, the photovoltaic power generation device is switched to the side of the plant power transformer with the largest predicted load power consumption value of the plant power transformer, and the photovoltaic power generation device is set to be in a full-power generation state, so that the power generated by the photovoltaic power generation device is fully utilized, and the maximum utilization of new energy is realized.

In one embodiment, the long-term trend due to electricity usage is repetitive, periodic; the power consumption in each day also has a short-term trend, for example, in summer, the power consumption is remarkably increased due to the large use of the air conditioner, and in the same period in different time periods, the power consumption in the same area is basically the same because the number of residents in the specified area is not greatly changed; it is possible to construct a trend curve of the used amount of electricity from the historical used amount of electricity and predict the future used amount of electricity from the trend curve. The first historical time period may be determined on a case-by-case basis, and may be one or more days, such as a week, a specified one or more months, etc.; and constructing a predicted load curve according to the collected electricity consumption in the appointed historical time period, and predicting the predicted load electricity consumption in the first time period according to the predicted load curve.

The embodiment of the invention has the following technical effects: in a designated area and a history period, the trend of the power consumption is more obvious periodically, a prediction curve can be constructed according to the trend, the power consumption of the local area can be better fitted, and the future power consumption can be more accurately predicted according to the prediction curve.

In one embodiment, during peak electricity price, the discharge prediction amount of the energy storage device is compared with the prediction load electricity consumption of each transformer, so that the discharge output electricity of the energy storage device is preferentially consumed on the local commercial power transformer side, and if the discharge prediction amount of the energy storage device is far larger than the prediction load electricity consumption of the commercial power, the energy storage device is switched to the plant electricity transformer side with the largest plant electricity prediction load electricity consumption value in the plant electricity transformers; in this embodiment, the energy storage device discharges according to the predicted load curve of the utility power or the predicted load curve of the plant power, so that the actual load discharge more suitable for the utility power transformer or the plant power transformer is realized, the output power of the energy storage device is utilized to the maximum extent, and the energy storage benefit is realized to the maximum extent.

Further, as shown in fig. 2, the N plant transformers include: a first plant transformer and a second plant transformer; wherein N is 2;

In one embodiment, the first third power switch cabinet is used for remotely switching the photovoltaic power generation device into one of the utility transformer, the first plant transformer or the second plant transformer; the second third power supply switching cabinet is used for remotely switching the energy storage device into one of the mains supply transformer, the first plant transformer or the second plant transformer; the first third power supply switching cabinet and the second third power supply switching cabinet are used for remote control switching, manual operation is avoided, and safety is improved; the first and second power switching cabinets are also used for providing overload, short circuit and voltage loss protection functions, so that the safety and stability are further improved.

The above technical solutions of the embodiments of the present invention are described in detail below with reference to specific application examples, and reference may be made to the foregoing related descriptions for technical details that are not described in the implementation process.

The technical scheme of the embodiment of the invention combines the load characteristics of the power plant, safely and reasonably introduces the distributed renewable energy source power generation through an intelligent control strategy, and realizes the maximized local consumption of new energy sources; the power plant distribution network is flexible by matching with a distributed energy storage battery; through the intelligent control of the intelligent three-switch cabinet (namely the first three-power-supply switch cabinet and the second three-power-supply switch cabinet), the actual power load of a power plant is taken as a trigger point, and safe and intelligent switching is realized from the economical aspect, so that the project benefit maximization, the power grid friendliness and the control intelligence are achieved.

In the embodiment of the invention, a prefabricated cabin of the light storage microgrid is built, and the whole system adopts a pure alternating current system architecture and comprises about 143.55kWp photovoltaic power generation systems (namely photovoltaic power generation devices), 100kW/497kWh intelligent energy storage systems and energy management systems (namely comprising energy storage devices and bidirectional converters). Three power switching cabinets are arranged to realize the switching of photovoltaic and energy storage among three grid-connected points respectively, the maximum consumption of the photovoltaic and the energy storage is guaranteed, and the photovoltaic power generation device adopts 290 blocks of 495Wp monocrystalline silicon assemblies and is installed on the top of a 3-span dormitory building. The energy storage device adopts 4 clusters of 124.4kWh lithium iron phosphate batteries and is integrated in a high-protection prefabricated cabin.

In the embodiment of the invention, the mains transformer is 1250kVA mains transformer, and peak-valley electricity prices are executed, wherein the specific electricity prices are shown in Table 1; the first plant transformer is a 2500kVA plant transformer, the second plant transformer is a 630kVA plant transformer, and one port price is executed, namely 0.663 yuan/kWh.

	Peak(s)	Flat plate	Grain
				Price of electricity	0.9999	0.6474	0.2034
Time period	9-11:30；14-16:30；19-21	7-9；11:30-14；16:30-19	23-7

TABLE 1 peak-to-valley electricity price of commercial power transformer

Photovoltaic switching main logic: the system has a load prediction function, and the prediction of the size of the commercial power load is taken as a main cause. When the predicted photovoltaic power generation amount of the expected photovoltaic power generation device is smaller than the predicted commercial power load power consumption amount of the commercial power transformer, the photovoltaic power generation is consumed under the 1250kVA commercial power transformer on the same day; when the predicted photovoltaic power generation amount is larger than the predicted load power consumption of the commercial power transformer, and the photovoltaic power generation cannot be completely absorbed by the load under the commercial power transformer, the photovoltaic power generation device is switched to the transformer in the plant (namely, the first plant power transformer or the second plant power transformer) to be absorbed on the same day; according to load prediction of 2500kVA station transformer (first station transformer) and 630kVA life transformer (second station transformer), the station transformer is preferentially switched to the station transformer with larger predicted load power consumption for consumption.

Energy storage switching main logic: the energy storage is executed according to a daily 'one charging and one discharging' strategy, and the energy storage charging time period is ensured at the commercial power side (namely the commercial power transformer side) because the 1250kVA commercial power transformer side has peak-valley electricity price and the low-valley electricity price at night is lower. According to the load size and the real-time electricity price condition predicted by different transformers, different transformers are selected to be switched in during energy storage and discharge, and energy storage benefit maximization is achieved.

As shown in fig. 3, which is a flowchart of a further microgrid tri-generation control method according to an embodiment of the present invention, first, load prediction is performed, in the load prediction, prediction is performed on predicted utility power load power consumption, predicted first plant power load power consumption, and predicted second plant power load power consumption for each transformer, for example, 1250kVA transformers, which are utility power transformers, and N plant power transformers (in this embodiment, 2500kVA transformers, which are first plant power transformers, and 630kVA transformers), and prediction is performed on predicted photovoltaic power generation amount for photovoltaic power generation devices. And judging whether the power failure of each transformer occurs or not, if so, generating a power failure report alarm, and waiting for the power failure to be processed. If no power failure occurs, three power supply switching cabinets are respectively arranged aiming at the photovoltaic power generation device and the energy storage device, so that the photovoltaic power generation device is switched into one of the transformers, the energy storage device is also switched into one of the transformers, and the charging and discharging states of the energy storage device are set. Specifically, for the energy storage device, when the actual electricity price of the mains supply transformer is a valley electricity price, the energy storage device is switched into the side of the mains supply transformer, and the energy storage device is set to be in a charging state, otherwise, the energy storage device discharges aiming at the currently switched-in transformer; and when the energy storage predicted discharge amount of the energy storage device is larger than the power consumption of the commercial power predicted load and is in the peak electricity price period, switching the energy storage device into one transformer side with larger power consumption of the plant electricity load in the first plant electricity transformer and the second plant electricity transformer, and setting the energy storage device to be in a discharge state, otherwise, discharging the energy storage device aiming at the commercial power transformer. Aiming at the photovoltaic power generation device, when the photovoltaic predicted power generation amount of the photovoltaic power generation device is smaller than or equal to the commercial power predicted load power consumption, the photovoltaic power generation device is switched into one side of a commercial power transformer, in the actual operation process, if the actual power generation amount of the photovoltaic power generation device is found to be larger than the actual commercial power load power consumption, the residual power is sent, and if the actual power generation amount of the photovoltaic power generation device is smaller than or equal to the actual commercial power load power consumption, the photovoltaic power generation device is set to be full-power generation. And when the photovoltaic predicted generating capacity of the photovoltaic power generation device is larger than the commercial power predicted load power consumption, switching the photovoltaic power generation device to one of the first plant power transformer and the second plant power transformer with larger predicted load power consumption, and setting the photovoltaic power generation device to generate power at full power.

The embodiment of the invention has the following technical effects: by a product form with high integration level, a product-level solution with multiple sources, loads, flexible power storage interconnection and panoramic information interaction is provided for the new energy microgrid of the power plant, plug and play of various energy sources and loads are realized, and the manufacturing cost of the system is saved. Practice the intelligent operation and management of the microgrid, realize stable economic operation and dynamic stable control by combining an energy management system, and provide basic conditions for commercial operation for distributed new energy consumption and utilization and large-scale electric vehicle ordered charging and discharging management. The embodiment of the invention can solve the problems of distributed power supply access of a power plant system, renewable energy utilization, green travel, user electric energy quality requirements, disaster resistance of a power system, relation with a smart power grid and the like, achieves the aim of maximizing local consumption of new energy, and achieves the effects of maximizing benefit, protecting the power grid and controlling intellectualization.

It should be understood that the specific order or hierarchy of steps in the processes disclosed is an example of exemplary approaches. Based upon design preferences, it is understood that the specific order or hierarchy of steps in the processes may be rearranged without departing from the scope of the present disclosure. The accompanying method claims present elements of the various steps in a sample order, and are not intended to be limited to the specific order or hierarchy presented.

In the foregoing detailed description, various features are grouped together in a single embodiment for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed embodiments of the subject matter require more features than are expressly recited in each claim. Rather, as the following claims reflect, invention lies in less than all features of a single disclosed embodiment. Thus, the following claims are hereby expressly incorporated into the detailed description, with each claim standing on its own as a separate preferred embodiment of the invention.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. To those skilled in the art; various modifications to these embodiments will be readily apparent, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the disclosure. Thus, the present disclosure is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

What has been described above includes examples of one or more embodiments. It is, of course, not possible to describe every conceivable combination of components or methodologies for purposes of describing the aforementioned embodiments, but one of ordinary skill in the art may recognize that many further combinations and permutations of various embodiments are possible. Accordingly, the embodiments described herein are intended to embrace all such alterations, modifications and variations that fall within the scope of the appended claims. Furthermore, to the extent that the term "includes" is used in either the detailed description or the claims, such term is intended to be inclusive in a manner similar to the term "comprising" as "comprising" is interpreted when employed as a transitional word in a claim. Furthermore, any use of the term "or" in the specification of the claims is intended to mean a "non-exclusive or".

Those of skill in the art will further appreciate that the various illustrative logical blocks, units, and steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both. To clearly illustrate the interchangeability of hardware and software, various illustrative components, elements, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design requirements of the overall system. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present embodiments.

The various illustrative logical blocks, or elements, described in connection with the embodiments disclosed herein may be implemented or performed with a general purpose processor, a digital signal processor, an Application Specific Integrated Circuit (ASIC), a field programmable gate array or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a digital signal processor and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a digital signal processor core, or any other similar configuration.

The steps of a method or algorithm described in connection with the embodiments disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module may be stored in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. For example, a storage medium may be coupled to the processor such the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC, which may be located in a user terminal. In the alternative, the processor and the storage medium may reside in different components in a user terminal.

In one or more exemplary designs, the functions described above in connection with the embodiments of the invention may be implemented in hardware, software, firmware, or any combination of the three. If implemented in software, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Computer-readable media includes both computer storage media and communication media that facilitate transfer of a computer program from one place to another. Storage media may be any available media that can be accessed by a general purpose or special purpose computer. For example, such computer-readable media can include, but is not limited to, RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to carry or store program code in the form of instructions or data structures and which can be read by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor. Additionally, any connection is properly termed a computer-readable medium, and, thus, is included if the software is transmitted from a website, server, or other remote source via a coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL), or wirelessly, e.g., infrared, radio, and microwave. Such discs (disk) and disks (disc) include compact disks, laser disks, optical disks, DVDs, floppy disks and blu-ray disks where disks usually reproduce data magnetically, while disks usually reproduce data optically with lasers. Combinations of the above may also be included in the computer-readable medium.

The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are merely exemplary embodiments of the present invention, and are not intended to limit the scope of the present invention, and any modifications, equivalent substitutions, improvements and the like made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims

1. A microgrid trisection control method is characterized in that the microgrid comprises: the method comprises the following steps of a mains supply transformer, N plant power transformers, a photovoltaic power generation device and an energy storage device, wherein the method comprises the following steps:

wherein N is a positive integer greater than or equal to 1.

2. The microgrid trisection control method of claim 1, further comprising, after setting a transformer selected to be switched in by the photovoltaic power generation device as the utility transformer if the photovoltaic predicted power generation amount is less than or equal to the utility predicted load power consumption amount:

3. The microgrid trisection control method of claim 1, wherein after the step of setting the transformer selectively switched in by the photovoltaic power generation device to be the one of the N plant transformers with the largest plant electricity predicted load electricity consumption value if the photovoltaic predicted power generation amount is larger than the commercial electricity predicted load electricity consumption, further comprises:

4. The microgrid trisection control method according to claim 1, wherein the predicting power consumption of the utility transformer in a specified first time period to obtain the predicted load power consumption of the utility power comprises:

5. The microgrid trisection control method according to claim 4, wherein the predicting power consumption of the N plant power transformers in the first time period to obtain respective plant power predicted load power consumption of each plant power transformer specifically comprises:

6. The microgrid trisection control method according to claim 5, wherein the setting the energy storage device to select the switched-in transformer and the setting the energy storage device to a discharge state according to the utility power predicted load electricity consumption and the respective plant power predicted load electricity consumptions of the N plant power transformers comprises:

7. The microgrid trisection control method of claim 1, wherein the N plant transformers include: a first plant transformer and a second plant transformer; wherein N is 2;