05369353 is referenced by 64 patents and cites 12 patents.

A controlled electrical energy storage apparatus for selectively storing electrical energy from an electrical grid, and selectively releasing the electric energy back into the grid. The apparatus includes a converter coupled to the grid, and a DC energy storage device coupled to the converter. The converter includes a switching circuit having a plurality of high speed electrical switches arranged in pairs. Each switch pair is coupled between one of the phase lines of the AC utility grid and the DC energy storage device. The power flow control unit supplies a power flow control waveform to the switch pairs. The power flow control waveform includes a real waveform for control of real power and an imaginary waveform for control of reactive power independently of the real power. By pulse-width modulating the switches at a high frequency, the converter controls instantaneous currents flowing through each of the phase lines for precise control of the real and reactive power.

Title
Controlled electrical energy storage apparatus for utility grids
Application Number
7/986798
Publication Number
5369353
Application Date
December 8, 1992
Publication Date
November 29, 1994
Inventor
William L Erdman
Brentwood
CA, US
Agent
Blakely Sokoloff Taylor & Zafman
Assignee
KENETECH Windpower
CA, US
IPC
G05F 1/70
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