Apparatus for storing power and method of controlling the same

• US 8,558,510 B2
• Filed: 10/27/2010
• Issued: 10/15/2013
• Est. Priority Date: 12/11/2009
• Status: Active Grant

• Current Assignee: Hanwha Solutions Corporation (Hanwha Corporation)
• Original Assignee: Samsung SDI Company Limited
• Inventors: Moon, Chong-Sop
• Primary Examiner(s): DIAO, M BAYE
• Application Number:
  US12/913,159
• Publication Number:
  US 20110140667A1
• Time in Patent Office: 1,084 Days
• Field of Search: 320/134, 320/140
• US Class Current: 320/134
• CPC Class Codes: H02J 2300/20 The dispersed energy generation being of renewable origin
• CPC Class Codes: H02J 2300/24 of photovoltaic origin
• CPC Class Codes: H02J 2300/26 involving maximum power point tracking control for photovoltaic sources maximum power point systems in particular G05F1/67
• CPC Class Codes: H02J 2300/28 The renewable source being wind energy wind motors F03D
• CPC Class Codes: H02J 2310/52 The controlling of the operation of the load not being the total disconnection of the load, i.e. entering a degraded mode or in current limitation
• CPC Class Codes: H02J 3/008 involving trading of energy or energy transmission rights
• CPC Class Codes: H02J 3/144 Demand-response operation of the power transmission or distribution network
• CPC Class Codes: H02J 3/32 using batteries with converting means
• CPC Class Codes: H02J 3/381 Dispersed generators
• CPC Class Codes: H02J 3/44 with means for ensuring correct phase sequence
• CPC Class Codes: H02J 7/00716 in response to integrated charge or discharge current
• CPC Class Codes: H02J 7/04 Regulation of charging current or voltage
• CPC Class Codes: H02J 7/35 with light sensitive cells
• CPC Class Codes: H02J 9/062 for AC powered loads
• CPC Class Codes: Y02B 10/70 Hybrid systems, e.g. uninterruptible or back-up power supplies integrating renewable energies
• CPC Class Codes: Y02B 70/30 Systems integrating technologies related to power network operation and communication or information technologies for improving the carbon footprint of the management of residential or tertiary loads, i.e. smart grids as climate change mitigation technology in the buildings sector, including also the last stages of power distribution and the control, monitoring or operating management systems at local level
• CPC Class Codes: Y02B 70/3225 Demand response systems, e.g. load shedding, peak shaving
• CPC Class Codes: Y02E 10/56 Power conversion systems, e.g. maximum power point trackers
• CPC Class Codes: Y02E 10/76 Power conversion electric or electronic aspects
• CPC Class Codes: Y02E 70/30 Systems combining energy storage with energy generation of non-fossil origin
• CPC Class Codes: Y02P 90/50 : Energy storage in industry with an added climate change mitigation effect
• CPC Class Codes: Y04S 20/222 : Demand response systems, e.g. load shedding, peak shaving
• CPC Class Codes: Y04S 20/248 : UPS systems or standby or emergency generators
• CPC Class Codes: Y04S 50/10 : Energy trading, including energy flowing from end-user application to grid

Abstract

Provided are a power storage apparatus and a method of controlling the power storage apparatus. The power storage apparatus stores power supplied from a power generation system or a power grid. The power storage apparatus supplies stored power to a load during an electric failure, and supplies stored power to the power grid. The power storage apparatus includes at least one battery cell, a battery management unit coupled to the battery cell, a bi-directional converter coupled to the battery management unit, a bi-directional inverter coupled between the bi-directional converter and the power grid, and a central controller controlling the operations of the bi-directional converter, the bi-directional inverter, and the battery management unit. An uninterruptible power supply (UPS) function may be performed to stabilize the power storage system including the power storage apparatus.

Claims

1. A power storage apparatus comprising:

a bi-directional inverter connected between a first node and a second node connected to a power grid and a load, the bi-directional inverter converting a direct current (DC) voltage supplied from the first node to an alternating current (AC) voltage and outputting the AC voltage to the second node, the bi-directional inverter converting an AC voltage supplied from the power grid to a DC voltage and outputting the DC voltage to the first node;

at least one battery cell;

a battery management unit for detecting a remaining amount of power in the at least one battery cell and controlling charging/discharging of the at least one battery cell;

a bi-directional converter connected between the battery management unit and the first node, the bi-directional converter converting a DC voltage supplied from the at least one battery cell to another DC voltage and outputting the another DC voltage to the bi-directional inverter via the first node, the bi-directional converter converting a DC voltage supplied from the bi-directional inverter to another DC voltage and outputting the another DC voltage to the at least one battery cell; and

a central controller performing a control operation for charging the at least one battery cell with power supplied from the power grid, the central controller controlling the battery management unit, the bi-directional converter, and the bi-directional inverter so as to supply power stored in the at least one battery cell to the power grid, the central controller blocking power supply from the at least one battery cell to the power grid when the remaining amount of power of the at least one battery cell is lower than a reference level.

2. The power storage apparatus of claim 1, wherein the central controller controls the battery management unit, the bi-directional converter, and the bi-directional inverter so as to supply the power from the at least one battery cell to the load when the power grid is in an abnormal state.

3. The power storage apparatus of claim 1, wherein the central controller controls the battery management unit, the bi-directional converter, and the bi-directional inverter so as to supply the power stored in the at least one battery cell to the load when power consumption of the load is equal to or greater than a reference power consumption level.

4. The power storage apparatus of claim 3, wherein the central controller controls the battery management unit, the bi-directional converter, and the bi-directional inverter so as not to supply the power stored in the at least one battery cell to the load even if the power consumption of the load is equal to or greater than the reference power consumption level, when the remaining power of the at least one battery cell is lower than the reference level.

5. The power storage apparatus of claim 1, further comprising a power conversion unit for converting power supplied from a power generation system into a DC voltage and outputting the DC voltage to the bi-directional converter via the first node, the bi-directional converter converting the DC voltage from the power conversion unit to another DC voltage and outputting the another DC voltage to the at least one battery cell.

6. The power storage apparatus of claim 5, wherein the power generation system includes a solar battery, and the power conversion unit controls a level of generated power so as to track a maximum power supply voltage from the solar battery by using a maximum power point tracker (MPPT) algorithm.

7. The power storage apparatus of claim 1, further comprising a voltage stabilization unit connected to the first node for stabilizing a voltage level at the first node.

8. The power storage apparatus of claim 1, further comprising:

a first switch connected between the bi-directional inverter and the second node; and

a second switch connected between the second node and the power grid, wherein the central controller turns the first switch and the second switch on when the power grid is in the normal state, and turns the first switch on and turns the second switch off when the power grid is in the abnormal state.