Compressed air energy storage generator

Patent metadata

Field	Value
Publication number	US-10868440-B2
Application number	US-201816603812-A
Country	US
Kind code	B2
Filing date	Apr 10, 2018
Priority date	Apr 26, 2017
Publication date	Dec 15, 2020
Grant date	Dec 15, 2020

Abstract

A compressed air energy storage generator includes a motor, a compressor, a pressure accumulator, an expander, a generator, an electric-motor inverter, a generator inverter, a feed command receiver, a discharge command receiver, and a controller. The controller includes a feed determination unit, a discharge determination unit, and an input and output adjustment unit, the feed determination unit being configured to determine whether a feed command value is smaller than minimum charge power, the discharge determination unit being configured to determine whether a discharge command value is smaller than minimum discharge power, the input and output adjustment unit being configured to control, when the feed determination unit determines that the feed command value is smaller than the minimum charge power or when the discharge determination unit determines that the discharge command value is smaller than the minimum discharge power, the inverters to simultaneously drive the motor and the generator.

First claim

The invention claimed is:

1. A compressed air energy storage generator comprising:
an electric motor configured to be driven with input power that fluctuates;
a compressor configured to be driven by the electric motor to compress air;
a pressure accumulator configured to hold the compressed air discharged from the compressor;
an expander configured to be driven with the compressed air supplied from the pressure accumulator;
a generator configured to be driven by the expander to supply, to a consumer facility, output power that fluctuates;
an electric-motor inverter configured to change a rotation speed of the electric motor;
a generator inverter configured to change a rotation speed of the generator;
a feed command receiver configured to receive the input power as a feed command value before feeding the input power;
a discharge command receiver configured to receive, from the consumer facility, demand power as a discharge command value before outputting the output power; and
a controller including a feed determination unit, a discharge determination unit, and an input and output adjustment unit, the feed determination unit being configured to determine whether the feed command value is smaller than minimum charge power corresponding to a minimum rotation speed of the electric motor, the discharge determination unit being configured to determine whether the discharge command value is smaller than minimum discharge power corresponding to a minimum rotation speed of the generator, the input and output adjustment unit being configured to control, when the feed determination unit determines that the feed command value is smaller than the minimum charge power or when the discharge determination unit determines that the discharge command value is smaller than the minimum discharge power, the electric-motor inverter and the generator inverter to simultaneously drive the electric motor and the generator.

2. The compressed air energy storage generator according to claim 1 , wherein
the controller further includes a feed shortage calculation unit configured to calculate, when the feed determination unit determines that the feed command value is smaller than the minimum charge power, a difference between the feed command value and the minimum charge power as a feed shortage amount, wherein
the input and output adjustment unit drives the generator to generate power equal to or greater than the feed shortage amount, and drives the electric motor with power that is equal to or greater than the minimum charge power and includes both the input power indicated by the feed command value and the power equal to or greater than the feed shortage amount generated by the generator.

3. The compressed air energy storage generator according to claim 1 , wherein
the controller further includes a discharge shortage calculation unit configured to calculate, when the discharge determination unit determines that the discharge command value is smaller than the minimum discharge power, a difference between the discharge command value and the minimum discharge power as a discharge shortage amount, wherein
the input and output adjustment unit drives the generator at the minimum rotation speed or higher and drives the electric motor with power that is equal to or greater than the discharge shortage amount and equal to or greater than the minimum charge power.

4. The compressed air energy storage generator according to claim 1 , wherein
pluralities of the compressors and the electric motors are provided, and
the controller further includes a control unit for leveling compression configured to control the electric-motor inverter to level off drive times of combinations of the compressors and the electric motors.

5. The compressed air energy storage generator according to claim 1 , wherein
pluralities of the expanders and the generators are provided, and
the controller further includes a control unit for leveling expansion configured to control the generator inverter to level off drive times of combinations of the expanders and the generators.

6. The compressed air energy storage generator according to claim 2 , wherein
pluralities of the compressors and the electric motors are provided, and
the controller further includes a control unit for leveling compression configured to control the electric-motor inverter to level off drive times of combinations of the compressors and the electric motors.

7. The compressed air energy storage generator according to claim 3 , wherein
pluralities of the compressors and the electric motors are provided, and
the controller further includes a control unit for leveling compression configured to control the electric-motor inverter to level off drive times of combinations of the compressors and the electric motors.

8. The compressed air energy storage generator according to claim 2 , wherein
pluralities of the expanders and the generators are provided, and
the controller further includes an control unit for leveling expansion configured to control the generator inverter to level off drive times of combinations of the expanders and the generators.

9. The compressed air energy storage generator according to claim 3 , wherein
pluralities of the expanders and the generators are provided, and
the controller further includes an control unit for leveling expansion configured to control the generator inverter to level off drive times of combinations of the expanders and the generators.

Assignees

• Kobe Steel Ltd

Inventors

• Sato Takashi
• Nakamichi Ryo
• Matsukuma Masaki
• Saruta Hiroki

Classifications

• H02J15/20 Primary

  using storage of pneumatic energy, e.g. compressed air energy storage [CAES] · CPC title

• Y02E60/16

  Mechanical energy storage, e.g. flywheels or pressurised fluids · CPC title

• F03D9/17

  storing energy in pressurised fluids · CPC title

• Y02E20/14

  Combined heat and power generation [CHP] · CPC title

• F05B2260/422

  in the form of potential energy, e.g. pressurized or pumped fluid · CPC title