High-temperature secondary battery based energy storage and power compensation system

• US 6,747,370 B2
• Filed: 05/11/2001
• Issued: 06/08/2004
• Est. Priority Date: 05/18/2000
• Status: Active Grant

• Current Assignee: NGK Insulators Limited
• Original Assignee: Korea Electric Power Corporation (Government of South Korea), NGK Insulators Limited
• Inventors: Abe, Hiroyuki
• Primary Examiner(s): TOATLEY, GREGORY J
• Application Number:
  US09/853,535
• Publication Number:
  US 20010043013A1
• Time in Patent Office: 1,124 Days
• Field of Search: 307/46, 307/66, 307/67, 307/80, 307/85, 320/135
• US Class Current: 307/66
• CPC Class Codes: H02J 3/1842 wherein at least one reactive element is actively controlled by a bridge converter, e.g. active filters
• CPC Class Codes: H02J 3/32 using batteries with converting means
• CPC Class Codes: H02J 9/06 with automatic change-over , e.g. UPS systems
• CPC Class Codes: Y02E 40/20 Active power filtering [APF]

Abstract

A high temperature secondary battery based energy storage and power compensation system wherein, an electric power supply system, electric load, and electric energy storage system including a high temperature secondary battery and power conversion system, are electrically connected with one another. When operating normally, electric power is supplied from the electric power supply system to the electric load, while the electric energy storage system operates to effect peak shaving and load leveling. A high speed switch is provided between the electric power supply system and the electric energy storage system, so that when a voltage sag or service interruption occurs while electric power is being supplied from the electric power supply system, the voltage sag is immediately detected and the switch is immediately opened, and electric power is immediately supplied from the electric energy storage system to the electric load to compensate for the voltage sag or service interruption.

Claims

1. A high-temperature secondary battery based energy storage and power compensation system, comprising:

an A.C. electric power supply system;

an electric load;

an electric energy storage system including a high-temperature secondary battery and a power conversion system,

wherein the electric power supply system, the electric load and the electric energy storage system are electrically connected, and from which, when operating normally, A.C. electric power is supplied directly from the electric power supply system to the electric load while the electric energy storage system operates to effect peak shaving and load leveling and

a high speed switch provided between the electric power supply system and the electric energy storage system;

wherein, when a voltage sag or a service interruption occurs in the electric power being supplied to the electric load from the electric power supply system, the voltage sag is immediately detected, the high speed switch is temporarily opened and electric power is immediately supplied from the electric energy storage system to the electric load in order to compensate for the voltage sag or the service interruption.

2. A high-temperature secondary battery based energy storage and power compensation system according to claim 1, wherein the high-temperature secondary battery comprises a sodium sulfur battery.

3. A high-temperature secondary battery based energy storage and power compensation system according to claim 1, wherein the electric energy storage system for compensating for the voltage sag or the service interruption is a system capable of outputting a compensation electric power which is 3 to 8 times a rated electric power of the electric energy storage system during peak shaving and load leveling.

4. A high-temperature secondary battery based energy storage and power compensation system according to claim 1, further comprising:

a back-up generator connected on the electric power compensation side of the high speed switch;

a voltage compensation controller capable of detecting when the high speed switch is opened, and sending a command in accordance with a detection signal to cause the electric energy storage system to discharge an entire electric load, and, at the same time, starting the back-up generator, so that if the electric power supply is not restored within a predetermined time period, the back-up generator is connected in parallel with the system, while at the same time the electric power supply from the electric energy storage system is stopped.

5. A high-temperature secondary battery based energy storage and power compensation system comprising the electric power supply system, the electric load, and the electric energy storage system including the high-temperature secondary battery and a power conversion system, all of which are electrically connected with one another so as to supply an electric power from the electric power supply system to the electric load under normal operation conditions, and operating the electric energy storage system in order to effect peak shaving and load leveling according to claim 1, wherein said system further comprises a control function capable of coping with a fluctuation derived from an event such as a spike and a frequency fluctuation in the electric power supplied, by detecting immediately such an event, and sending a signal based on detection to the electric energy storage system in order to compensate for the fluctuation.

6. A high-temperature secondary battery based energy storage and power compensation system according to claim 1, wherein spare high temperature batteries connected in parallel with module high temperature batteries are provided so as to cope with a case that module batteries fail, by switching from failed module batteries to the spare high temperature batteries.