METHOD, DEVICE, AND SYSTEM FOR CONTROLLING CHARGING AND DISCHARGING OF ENERGY STORAGE APPARATUS

• US 20130162037A1
• Filed: 12/17/2012
• Published: 06/27/2013
• Est. Priority Date: 12/26/2011
• Status: Active Grant

• Current Assignee: KT Corporation
• Original Assignee: KT Corporation
• Inventors: KIM, Min-Gyung, LEE, Min-Jin
• Granted Patent: US 9,825,479 B2
• Time in Patent Office: Days
• US Class Current: 307/24
• CPC Class Codes: H02J 13/00004 characterised by the power network being locally controlled
• CPC Class Codes: H02J 13/00007 using the power network as support for the transmission
• CPC Class Codes: H02J 13/00016 using a wired telecommunication network or a data transmission bus
• CPC Class Codes: H02J 13/00028 involving the use of Internet protocols
• CPC Class Codes: H02J 2300/24 of photovoltaic origin
• CPC Class Codes: H02J 2310/12 The local stationary network supplying a household or a building
• CPC Class Codes: H02J 3/003 Load forecast, e.g. methods or systems for forecasting future load demand
• CPC Class Codes: H02J 3/14 by switching loads on to, or off from, network, e.g. progressively balanced loading
• CPC Class Codes: H02J 3/32 using batteries with converting means
• CPC Class Codes: H02J 3/381 Dispersed generators
• CPC Class Codes: H02J 3/466 Scheduling the operation of the generators, e.g. connecting or disconnecting generators to meet a given demand
• CPC Class Codes: H02J 7/0068 Battery or charger load switching, e.g. concurrent charging and load supply H02J7/0013 takes precedence
• CPC Class Codes: Y02B 70/3225 Demand response systems, e.g. load shedding, peak shaving
• CPC Class Codes: Y02B 90/20 Smart grids as enabling technology in buildings sector smart grids supporting the management or operation of end-user stationary applications in general, or like technologies with no associated climate change mitigation effect Y04S20/00
• CPC Class Codes: Y02E 10/56 Power conversion systems, e.g. maximum power point trackers
• CPC Class Codes: Y02E 40/70 Smart grids as climate change mitigation technology in the energy generation sector
• CPC Class Codes: Y02E 60/00 Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
• CPC Class Codes: Y02E 70/30 Systems combining energy storage with energy generation of non-fossil origin
• CPC Class Codes: Y04S 10/123 the energy generation units being or involving renewable energy sources
• CPC Class Codes: Y04S 20/12 Energy storage units, uninterruptible power supply [UPS] systems or standby or emergency generators, e.g. in the last power distribution stages
• CPC Class Codes: Y04S 20/222 : Demand response systems, e.g. load shedding, peak shaving
• CPC Class Codes: Y04S 40/121 : using the power network as support for the transmission
• CPC Class Codes: Y04S 40/124 : using wired telecommunication networks or data transmission busses

Abstract

A charging/discharging control system of an energy storage apparatus includes a weather information collection module, a load information collection module, a load grouping module which classifies a plurality of loads into at least one load group based on a load correlation according to a predetermined condition, and an energy storage apparatus charging/discharging control module which determines a battery charging or discharging level per time slot of each of a plurality of energy storage apparatuses by using at least one of an estimated load amount of each load per time slot, a battery charging amount of the energy storage apparatus per time slot via solar generation, and a battery charging amount per time slot via system power, wherein a particular load corresponding to a lowest rate for a unit load is determined by using battery charging/discharging information and power rate information per time slot.

Claims

1. A method for controlling charging or discharging of an energy storage apparatus, the method comprising:

classifying a plurality of loads provided with a plurality of energy storage apparatuses into at least one load group based on a load correlation according to a predetermined condition;

determining a battery charging or discharging level per time slot of each respective energy storage apparatus provided to each corresponding load;

operating said each respective energy storage apparatus according to the respective determined battery charging or discharging level; and

determining a particular load indicating a lowest rate for a load by using battery charging/discharging information and power rate information per time slot, and generating an energy storage apparatus scheduling information based on the battery charging or discharging level corresponding to the determined particular load,

wherein the determining the battery charging or discharging level is based on at least one of an estimated load amount of each load per time slot, a solar-generated battery charging amount of the respective energy storage apparatus per time slot via solar generation, and a grid-generated battery charging amount per time slot via a grid-connected electronic power system.

2. The method of claim 1, wherein the classifying the plurality of loads comprises:

building a database configured to store at least one of environment information, weather information, and power consumption information relating to the plurality of the loads and that are collected in real time or during a predetermined period of time;

determining at least one load corresponding to an equivalent area, an equivalent date, and an equivalent weather condition based on information stored in the database;

calculating average power consumption information per date based on power consumption information corresponding to the determined at least one load; and

determining the load correlation based on the power consumption information corresponding to the determined at least one load and the calculated average power consumption information.

3. The method of claim 2, wherein the classifying the plurality of loads further comprises:

determining, based on the determined load correlation, at least one load having same pattern as a set of loads which belong to an area having a highest load correlation according to the information stored in the database, and classifying the at least one determined load into same group.

4. The method of claim 1, wherein the determining a battery charging or discharging level comprises:

setting an initial value of the estimated load amount by using power consumption information per time slot in the unit of the load group;

setting an initial value of the respective solar-generated battery charging amount and the respective grid-generated battery charging amount of the corresponding energy storage apparatus provided to each respective load in the unit of the load group; and

determining a respective target charging amount per time slot for each of the plurality of the energy storage apparatuses that belongs to the load group unit, wherein the respective target charging amount per time slot is determined by summing an estimated respective solar-generated battery charging amount and an estimated respective grid-generated battery charging amount.

5. The method of claim 4, wherein the initial value of the estimated load amount is set as being equal to an average power consumption which is determined by using information relating to power consumption per time slot in the load group.

6. The method of claim 4, wherein the initial value of the respective solar-generated battery charging amount is set as being equal to an average solar-generated battery charging amount which is determined by using information relating to a respective solar-generated battery charging amount per time slot in the unit of the load group, and the initial value of the respective grid-generated battery charging amount is set to zero.

7. The method of claim 4, wherein the estimated respective solar-generated battery charging amount used for determining the respective target charging amount per time slot is determined as being equal to a maximum solar-generated battery charging amount of a corresponding time slot within a time slot in which the solar generation is available.

8. The method of claim 4, wherein the estimated respective grid-generated battery charging amount used for determining the respective target charging amount per time slot is determined by:

calculating a sum of an estimated load amount per time slot by accumulating the estimated load amount per time slot, within a predetermined cycle, in the unit of the load group for a predetermined date; and

calculating a required respective grid-generated battery charging amount per time slot within the predetermined cycle by using the calculated sum of the estimated load amount and the respective solar-generated battery charging amount of a previous time slot.

9. The method of claim 8, further comprising:

calculating an actual rate per time slot by using a rate per time slot in the previous time slot and an inverse number of charging/discharging efficiency, and determining a particular time slot for which the calculated actual rate is lowest;

comparing a calculated actual rate of a particular time slot which immediately precedes a time slot for which an estimated respective grid-generated battery charging amount is to be determined by using an electricity rate relating to the particular time slot; and

compensating the required respective grid-generated battery charging amount based on a result of the comparing.

10. The method of claim 9, wherein, when the actual rate of the particular time slot is less than the electricity rate of the time slot immediately preceding the particular time slot, the method further comprises:

determining the estimated respective grid-generated battery charging amount by summing the actual respective grid-generated battery charging amount of the particular time slot and the required respective grid-generated battery charging amount per time slot; and

compensating the required respective grid-generated battery charging amount per time slot by subtracting the actual respective grid-generated battery charging amount of the particular time slot from the required respective grid-generated battery charging amount per time slot.

11. The method of claim 10, further comprising:

determining a sum of a respective grid-generated battery charging amount per time slot based on a grid-generated battery charging amount per time slot within the predetermined cycle; and

comparing the determined sum of the respective grid-generated battery charging amount per time slot with the required respective grid-generated charging amount in a same time slot, wherein the determining the estimated respective grid-generated battery charging amount and the compensating the required respective grid-generated battery charging amount are repeatedly performed based on a result of the comparing.

12. The method of claim 1, wherein the determining a battery charging or discharging level comprises:

determining a discharging level of the energy storage apparatus as being equal to a sum of the respective solar-generated battery charging amount per time slot and the respective grid-generated battery charging amount per time slot minus an estimated load amount per time slot.

13. The method of claim 1, wherein the determining a particular load indicating a lowest rate comprises:

collecting the battery charging/discharging information including the solar-generated battery charging amount, the grid-generated battery charging amount, an actual load amount, and a battery discharging amount in the energy storage apparatus operated according to the operating of said each respective energy storage apparatus;

determining the particular load corresponding to the lowest rate for the unit load by using the battery charging/discharging information and the power rate information per time slot; and

scheduling an optimized charging/discharging level of the energy storage apparatus based on the solar-generated battery charging amount per time slot, the grid-generated battery charging amount, and the battery discharging amount corresponding to the particular load.

14. The method of claim 13, wherein the scheduling the optimized charging/discharging level of the energy storage apparatus comprises:

applying a variation error of a predetermined range to calculate an optimized solar-generated battery charging amount per time slot, an optimized grid-generated battery charging amount, and an optimized battery discharging level determined based on an initial result of the scheduling.

15. A system for controlling charging or discharging of an energy storage apparatus, the system comprising:

a weather information collection module configured to collect weather information corresponding to each of a plurality of loads provided with a corresponding plurality of energy storage apparatuses;

a load information collection module configured to collect environment information and power consumption information relating to each of the plurality of the loads;

a load grouping module configured to classify the plurality of the loads into at least one load group based on a load correlation according to a predetermined condition; and

an energy storage apparatus charging/discharging control module configured to determine a battery charging or discharging level per time slot of each of the plurality of the energy storage apparatuses by using at least one of an estimated load amount of each load per time slot, a solar-generated battery charging amount of the respective energy storage apparatus per time slot via solar generation, and a grid-generated battery charging amount per time slot via a grid-connected electronic power system,

wherein the energy storage apparatus charging/discharging control module determines a particular load corresponding to a lowest rate for a unit load by using battery charging/discharging information relating to an operation of the energy storage apparatus based on the determined battery charging or discharging level and power rate information per time slot, and schedules a charging/discharging level of the energy storage apparatus based on the determined battery charging or discharging level corresponding to the particular load.