ENERGY STORAGE MODULE WITH DC VOLTAGE INTERMEDIATE CIRCUIT

• US 20150311751A1
• Filed: 09/10/2013
• Published: 10/29/2015
• Est. Priority Date: 09/28/2012
• Status: Active Grant

• Current Assignee: Enrichment Technology Company Limited
• Original Assignee: Enrichment Technology Company Limited
• Inventors: vor dem Esche, Ing.Rainer, Schfer, Christoph, Treppmann, Ing. Christoph
• Granted Patent: US 10,186,899 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H02J 15/007 involving storage in the form of mechanical energy, e.g. fly-wheels
• CPC Class Codes: H02J 3/30 using dynamo-electric machines coupled to flywheels
• CPC Class Codes: H02J 9/08 requiring starting of a prime-mover
• CPC Class Codes: Y02E 60/16 Mechanical energy storage, e.g. flywheels or pressurised fluids
• CPC Class Codes: Y02P 90/50 Energy storage in industry with an added climate change mitigation effect

Abstract

An energy storage module is provided for reversibly storing electrical energy in the form of mechanical rotation energy. The energy storage module comprises a plurality of flywheel storage units, at least one control system and at least one module control unit, wherein the flywheel storage units are connected electrically in parallel by means of a common DC voltage intermediate circuit, and the control system or systems is/are connected to the common DC voltage intermediate circuit by way of the respective output side and to at least one external voltage grid by way of the respective input side, wherein the module control unit is provided for transmitting suitable prespecified torques to the flywheel storage units for emitting or absorbing energy to/from the DC voltage intermediate circuit, and at least one of the control systems is designed to control the DC voltage in the DC voltage intermediate circuit.

Claims

1. An energy storage module for reversibly storing electrical energy in the form of mechanical rotation energy, comprising a plurality of flywheel storage units, at least one control system and at least one module control unit, wherein the flywheel storage units are connected electrically in parallel by means of a common DC voltage intermediate circuit and the control system or systems is/are connected to the common DC voltage intermediate circuit by way of the respective output side and to at least one external voltage grid by way of the respective input side, wherein the module control unit is provided for transmitting suitable prespecified torques to the flywheel storage units for emitting or absorbing energy to/from the DC voltage intermediate circuit, and at least one of the control systems is designed to control the DC voltage in the DC voltage intermediate circuit such that the DC voltage remains substantially constant between an upper threshold value and a lower threshold value when energy is emitted into the external voltage grid or systems and when energy is absorbed from the external voltage grid or systems.

2. The energy storage module according to claim 1, characterized in that the module control unit is provided to generate and transmit the prespecified torques for the flywheel storage units in a time-related manner, in response to which the flywheel storage units feed or remove electricity in the DC voltage intermediate circuit due to the time-related prespecified torques.

3. The energy storage module according to claim 2, characterized in that each flywheel storage unit receives individual prespecified torques from the module control unit.

4. The energy storage module according claim 1, characterized in that each of the flywheel storage units comprises an electromagnetic transducer, which is connected electrically to the DC voltage intermediate circuit via a motor control, preferably a frequency converter.

5. The energy storage module according to claim 4, characterized in that the motor controls of all of the flywheel storage units are provided to continuously monitor the DC voltage in the DC voltage intermediate circuit against the upper threshold value and to independently prevent any power flow from the flywheel storage units into the DC voltage intermediate circuit no later than when the upper threshold value has been exceeded.

6. The energy storage module according to claim 4, characterized in that the module control unit recalls current speeds of the individual flywheel storage units from the motor controls thereof and determines a respective current charge state of the individual flywheel storage units from the recalled speed.

7. The energy storage module according to claim 1, characterized in that an upper speed limitation and/or a lower speed limitation is implemented in the motor control of the flywheel storage units, the upper speed limitation and/or lower speed limitation is preferably implemented by means of a component, which is provided for this purpose.

8. The energy storage module according to claim 1, characterized in that upper speed limitations and/or lower speed limitations for the prespecified torques are implemented in the module control unit, the speed limitations are preferably implemented in a computer program as instructions.

9. The energy storage module according to claim 1, characterized in that the energy storage module comprises one or more measuring units for continuously measuring the voltage quality of the external voltage grid or systems.

10. The energy storage module according to claim 1, characterized in that the module control unit is designed to receive external data and to adapt the prespecified torques to the received external data, such external data are preferably physical measured values, logical parameters, real time control commands or control commands for sequence control.

11. The energy storage module according to claim 1, characterized in that the energy storage module furthermore comprises auxiliary units for operating the flywheel storage units and that the module control unit is designed to adapt a control of the auxiliary units to received internal operating data or external data, the internal operating data thereby preferably comprise thermal loads within the energy storage module, such as of the flywheel storage or of further module-internal systems.

12. The energy storage module according to claim 1, characterized in that the energy storage module additionally comprises one or more power sinks connected to the auxiliary units.

13. A method for controlling an energy storage module according to claim 1, wherein a plurality of flywheel storage units are connected electrically in parallel by means of a common DC voltage intermediate circuit and one or more control systems are connected to the common DC voltage intermediate circuit by way of the respective output side and to at least one external voltage grid by way of the respective input side, wherein one of the control systems is provided to keep the DC voltage in the DC voltage intermediate circuit substantially constant between an upper threshold value and a lower threshold value, comprising the steps:

transmitting a prespecified torque for accelerating the flywheel control units by means of the module control unit to the flywheel units in response to an energy flow from the external voltage grid into the DC voltage intermediate circuit or

transmitting a prespecified torque for braking the flywheel storage units by means of the module control unit to the flywheel storage units in response to an energy flow from the DC voltage intermediate circuit into the external voltage grid or

no transmission of prespecified torques for the flywheel storage units in response to no energy flow into or from the DC voltage intermediate circuit.

14. The method according to claim 13, wherein each of the flywheel storage units is electrically connected to the DC voltage intermediate circuit via a motor control, preferably a frequency converter, comprising the further steps:

continuously monitoring the DC voltage in the DC voltage intermediate circuit against the upper threshold value by the motor controls of all of the flywheel storage units; and

independently preventing any power flow from the flywheel storage units into the DC voltage intermediate circuit no later than when the upper threshold value of the DC voltage has been exceeded in the DC voltage intermediate circuit by the motor controls of all of the flywheel storage units.