US6410992B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
System and method for dual mode control of a turbogenerator/motor
Assignee: Capstone Green Energy Corp
•
Filing: 2000-08-23
•
Granted: 2002-06-25
•
Expires: 2020-08-23
Abstract
Abstract A method of controlling a permanent magnet turbogenerator/motor includes providing a protected load connected in parallel with the turbogenerator/motor through a pulse width modulated inverter configured in a first operating mode to supply controlled current from the turbogenerator/motor to a utility electrical power source, and selectively connected to the utility electrical power source through an isolation device, monitoring the utility electrical power source, and automatically disconnecting the protected load from the utility electrical power source while reconfiguring the pulse width modulated inverter in a second operating mode to supply controlled voltage to the protected load when a fault is detected in the utility electrical power source. The present invention provides an external or integrated dual mode controller which can be used to provide automatic transitions of a turbogenerator/motor between grid-connected modes where a PWM inverter provides a controlled AC current source to stand-alone modes where the PWM inverter provides a controlled AC voltage source to a protected load. Three phase rotation sequence can be set to positive or negative rotation, or be set to the last measured rotation for the utility grid to enable automatic transitions from stand-alone to grid-connect modes. In addition, the present invention provides for detecting a reference phase angle of the three-phase power provided by a utility grid such that gradual synchronization/resynchronization of a protected parallel connected load can be performed by appropriately controlling the PWM inverter prior to re-connection to the utility grid.
Inventors
- 👤 Simon R. Wall
- 👤 Joel B. Wacknov
- 👤 Mark G. Gilbreth
- 👤 Ken Keller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 20:10
CPC Classifications
H; H02; H02P; H02P9/00; H02P9/04; H02J; H02J3/00; H02J3/38; H02J3/40; H02J3/42; H02P9/02
Claims Analysis
Total Claims: 54
Claim 1
Independent Claim
111 words
A method of controlling a permanent magnet turbogenerator/motor comprising: providing a protected load connected in parallel with the turbogenerator/motor through a pulse width modulated inverter configured in a first operating mode to supply controlled current from the turbogenerator/motor to a utility electrical power source, and selectively connected to the utility electrical power source through an isolation device; monitoring the utility electrical power source; and automatically disconnecting the protected load from the utility electrical power source by opening the isolation device and reconfiguring the pulse width modulated inverter in a second operating mode to supply controlled voltage to the protected load when a fault is detected in the utility electrical power source.
Claim 2
Independent Claim
111 words
A method of controlling a permanent magnet turbogenerator/motor comprising: providing a protected load connected in parallel with the turbogenerator/motor through a pulse width modulated inverter configured in a first operating mode to supply controlled current from the turbogenerator/motor to a utility electrical power source, and selectively connected to the utility electrical power source through an isolation device; monitoring the utility electrical power source; and automatically disconnecting the protected load from the utility electrical power source by opening the isolation device and reconfiguring the pulse width modulated inverter in a second operating mode to supply controlled voltage to the protected load when a fault is detected in the utility electrical power source.
Claim 3
Dependent Claim
24 words
The method of claim 1 wherein monitoring the utility electrical power source comprises monitoring a phase rotation sequence of the utility electrical power source.
Claim 4
Dependent Claim
24 words
The method of claim 1 wherein monitoring the utility electrical power source comprises monitoring a phase reference angle of the utility electrical power source.
Claim 5
Dependent Claim
24 words
The method of claim 1 wherein monitoring the utility electrical power source comprises detecting loss of power supplied by the utility electrical power source.
Claim 6
Dependent Claim
53 words
The method of claim 1 further comprising: automatically reconfiguring the pulse width modulated inverter to supply controlled current from the turbogenerator/motor when the step of monitoring determines the utility electrical power source is acceptable for reconnection; and controlling the isolation device to automatically reconnect the protected load to the utility electrical power source.
Claim 7
Dependent Claim
73 words
The method of claim 5 wherein the monitoring step includes determining a reference phase angle of the electrical utility power source, the method further comprising controlling the pulse width modulated inverter to synchronize phase angle of the controlled voltage supplied to the protected load with the reference phase angle of the electrical utility power source prior to controlling the isolation device to automatically reconnect the protected load to the utility electrical power source.
Claim 8
Dependent Claim
37 words
The method of claim 1 further comprising: providing utility electrical power to the permanent magnet turbogenerator/motor through the pulse width modulated inverter to start the permanent magnet turbogenerator/motor to achieve self-sustaining operation of the permanent magnet turbogenerator/motor.
Claim 9
Dependent Claim
57 words
The method of claim 1 further comprising: providing an energy storage and discharge system for the pulse width modulated inverter to provide electrical energy to the inverter when utility electrical power is unavailable to start the permanent magnet turbogenerator/motor and during self-sustained operation when the permanent magnet turbogenerator/motor cannot meet an instantaneous load requirement during self-sustained operation.
Claim 10
Independent Claim
132 words
A system for controlling a permanent magnet turbogenerator/motor having an associated protected load, the system comprising: a controllable isolating device for selectively connecting the protected load in parallel with a utility electrical power source; an inverter configurable in a first operating mode to supply power from the turbogenerator/motor to the utility electrical power source, and a second operating mode to supply power from the turbogenerator/motor to the protected load; and a controller in communication with the controllable isolating device and the inverter, the controller selectively monitoring the utility electrical power source to detect a power source fault, opening the isolating device to disconnect the protected load from the utility electrical power source, and automatically transitioning from the first operating mode to the second operating mode to provide power to the protected load.
Claim 11
Independent Claim
132 words
A system for controlling a permanent magnet turbogenerator/motor having an associated protected load, the system comprising: a controllable isolating device for selectively connecting the protected load in parallel with a utility electrical power source; an inverter configurable in a first operating mode to supply power from the turbogenerator/motor to the utility electrical power source, and a second operating mode to supply power from the turbogenerator/motor to the protected load; and a controller in communication with the controllable isolating device and the inverter, the controller selectively monitoring the utility electrical power source to detect a power source fault, opening the isolating device to disconnect the protected load from the utility electrical power source, and automatically transitioning from the first operating mode to the second operating mode to provide power to the protected load.
Claim 12
Dependent Claim
27 words
The system of claim 9 further comprising means for monitoring the utility electrical power source to detect a phase rotation sequence of the utility electrical power source.
Claim 13
Dependent Claim
27 words
The system of claim 9 further comprising means for monitoring the utility electrical power source to determine a phase reference angle of the utility electrical power source.
Claim 14
Dependent Claim
27 words
The system of claim 9 further comprising means for monitoring the utility electrical power source to detect loss of power supplied by the utility electrical power source.
Claim 15
Dependent Claim
56 words
The system of claim 9 wherein the controller includes control logic for automatically transitioning from the second operating mode to the first operating mode after determining that the utility electrical power source is acceptable for reconnection and control logic for operating the isolation device to automatically reconnect the protected load to the utility electrical power source.
Claim 16
Dependent Claim
68 words
The system of claim 9 further comprising means for determining a reference phase angle of the electrical utility power source, wherein the controller controls the inverter to synchronize phase angle of the controlled voltage supplied to the protected load with the reference phase angle of the electrical utility power source prior to controlling the isolation device to automatically reconnect the protected load to the utility electrical power source.
Claim 17
Dependent Claim
21 words
The system of claim 9 wherein the controllable isolation device comprises an electronic switch connected in series with a mechanical switch.
Claim 18
Dependent Claim
12 words
The system of claim 15 wherein the electronic switch comprises a thyristor.
Claim 19
Dependent Claim
14 words
The system of claim 15 wherein the mechanical switch comprises a motorized circuit breaker.
Claim 20
Dependent Claim
12 words
The system of claim 15 wherein the mechanical switch comprises a contactor.
Claim 21
Dependent Claim
15 words
The system of claim 9 wherein the controllable isolation device comprises a motorized circuit breaker.
Claim 22
Dependent Claim
13 words
The system of claim 9 wherein the controllable isolation device comprises a contactor.
Claim 23
Dependent Claim
57 words
The system of claim 9 further comprising: an energy storage and discharge system in communication with the controller for providing electrical energy to the permanent magnet turbogenerator/motor when utility electrical power is unavailable to start the permanent magnet turbogenerator/motor and/or during self-sustained operation when the permanent magnet turbogenerator/motor cannot meet an instantaneous load requirement during self-sustained operation.
Claim 24
Independent Claim
231 words
A system for controlling a permanent magnet turbogenerator/motor to transition between a grid-connect operating mode in which the permanent magnet turbogenerator/motor is connected in parallel with an electrical utility power grid, and a stand-alone mode in which the permanent magnet turbogenerator/motor is disconnected from the electrical utility power grid, the system comprising: a first controller having a configurable pulse width modulated inverter operably associated with the permanent magnet turbogenerator/motor, the configurable pulse width modulated inverter for supplying controlled AC current to the electrical utility power grid when operating in the grid-connect operating mode and for supplying controlled voltage from the turbogenerator/motor when operating in the stand-alone operating mode; an isolating device for controllably connecting a protected load and the first controller to the electrical utility power grid; a second controller connected to the electrical utility power grid and in communication with the first controller and the isolating device, wherein the second controller monitors the electrical utility power grid to detect loss of grid power and communicates a grid transfer command to the first controller when a loss of grid power is detected such that the first controller transitions the pulse width modulated inverter from the grid-connect operating mode to the stand-alone operating mode and communicates corresponding status information to the second controller, the second controller then controlling the isolating device to disconnect the protected load from the electrical utility power grid.
Claim 25
Independent Claim
231 words
A system for controlling a permanent magnet turbogenerator/motor to transition between a grid-connect operating mode in which the permanent magnet turbogenerator/motor is connected in parallel with an electrical utility power grid, and a stand-alone mode in which the permanent magnet turbogenerator/motor is disconnected from the electrical utility power grid, the system comprising: a first controller having a configurable pulse width modulated inverter operably associated with the permanent magnet turbogenerator/motor, the configurable pulse width modulated inverter for supplying controlled AC current to the electrical utility power grid when operating in the grid-connect operating mode and for supplying controlled voltage from the turbogenerator/motor when operating in the stand-alone operating mode; an isolating device for controllably connecting a protected load and the first controller to the electrical utility power grid; a second controller connected to the electrical utility power grid and in communication with the first controller and the isolating device, wherein the second controller monitors the electrical utility power grid to detect loss of grid power and communicates a grid transfer command to the first controller when a loss of grid power is detected such that the first controller transitions the pulse width modulated inverter from the grid-connect operating mode to the stand-alone operating mode and communicates corresponding status information to the second controller, the second controller then controlling the isolating device to disconnect the protected load from the electrical utility power grid.
Claim 26
Dependent Claim
42 words
The system of claim 22 further comprising: an energy storage and discharge system in communication with the first controller to provide electrical energy to the pulse width modulated inverter during transitions from the grid connect operating mode to the stand-alone operating mode.
Claim 27
Dependent Claim
85 words
The system of claim 22 wherein the second controller monitors the electrical utility power grid to determine when the power grid is acceptable for reconnection, the second controller communicating a command to the first controller such that the first controller automatically transitions the pulse width modulated inverter from the stand-by operating mode to the grid-connect operating mode and communicates corresponding status information to the second controller, the second controller then controlling the isolating device to reconnect the protected load to the electrical utility power grid.
Claim 28
Dependent Claim
25 words
The system of claim 22 wherein the first controller monitors the electrical utility power grid to determine a phase rotation sequence of the power grid.
Claim 29
Dependent Claim
42 words
The system of claim 25 wherein the first controller controls the pulse width modulated inverter to provide the same phase rotation sequence to the protected load as the electrical utility power grid prior to transitioning between the stand-by and grid-connect operating modes.
Claim 30
Dependent Claim
32 words
The system of claim 22 wherein the second controller monitors the electrical utility power grid to determine a phase reference angle of the power grid and communicates this to the first controller.
Claim 31
Dependent Claim
42 words
The system of claim 27 wherein the first controller controls the pulse width modulated inverter to provide the same phase reference angle to the protected load as the electrical utility power grid prior to transitioning between the stand-by and grid-connect operating modes.
Claim 32
Independent Claim
181 words
A method of transitioning a permanent magnet turbogenerator/motor based electric power generation system between operating modes, one operating mode being a grid connect mode in which the permanent magnet turbogenerator/motor based electric power generation system is connected in parallel with an electric utility power grid, and the other operating mode being a stand-alone mode in which the permanent magnet turbogenerator/motor based electric power generation system is not connected in parallel with an electric utility power grid, the method comprising: when the permanent magnet turbogenerator/motor based electric power generation system is operating in grid connect mode, monitoring the electric utihty power grid to detect a fault, and opening an isolation device to automatically disconnect the permanent magnet turbogenerator/motor based electric power generation system from the electric utility power grid; and when the permanent magnet turbogenerator/motor based electric power generation system is operating in stand-alone mode, monitoring the electric utility power grid to determine when reconnection is acceptable, and closing the isolation device to automatically reconnect the permanent magnet turbogenerator/motor based electric power generation system in parallel with the electric utility power grid.
Claim 33
Independent Claim
181 words
A method of transitioning a permanent magnet turbogenerator/motor based electric power generation system between operating modes, one operating mode being a grid connect mode in which the permanent magnet turbogenerator/motor based electric power generation system is connected in parallel with an electric utility power grid, and the other operating mode being a stand-alone mode in which the permanent magnet turbogenerator/motor based electric power generation system is not connected in parallel with an electric utility power grid, the method comprising: when the permanent magnet turbogenerator/motor based electric power generation system is operating in grid connect mode, monitoring the electric utihty power grid to detect a fault, and opening an isolation device to automatically disconnect the permanent magnet turbogenerator/motor based electric power generation system from the electric utility power grid; and when the permanent magnet turbogenerator/motor based electric power generation system is operating in stand-alone mode, monitoring the electric utility power grid to determine when reconnection is acceptable, and closing the isolation device to automatically reconnect the permanent magnet turbogenerator/motor based electric power generation system in parallel with the electric utility power grid.
Claim 34
Dependent Claim
51 words
The method of claim 29 further comprising: monitoring the electric utility power grid to determine a phase rotation sequence; and synchronizing phase rotation sequence of the permanent magnet turbogenerator/motor based electric power generation system with the phase rotation sequence of the electric utility power grid prior to transitioning between operating modes.
Claim 35
Dependent Claim
51 words
The method of claim 29 further comprising: monitoring the electric utility power grid to determine a phase reference angle; and synchronizing phase reference angle of the permanent magnet turbogenerator/motor based electric power generation system with the phase reference angle of the electric utility power grid prior to transitioning between operating modes.
Claim 36
Dependent Claim
48 words
The method of claim 29 further comprising: when the permanent magnet turbogenerator/motor based electric power generation system is operating in stand-alone mode, modifying phase rotation sequence of power generated by the permanent magnet turbogenerator/ motor based electric power generation system based on a received phase rotation sequence command.
Claim 37
Independent Claim
175 words
A system for controlling a permanent magnet turbogenerator/motor to transition between a grid-connect operating mode in which the permanent magnet turbogenerator/motor is connected in parallel with an electrical utility power grid, and a stand-alone mode in which the permanent magnet turbogenerator/motor is, disconnected from the electrical utility power grid, the system comprising: an isolating device for controllably connecting and disconnecting a protected load and the turbogenerator/motor to the electrical utility power grid; a controller in communication with the controllable isolating device, the controller including a configurable pulse width modulated inverter operably associated with the permanent magnet turbogenerator/motor for supplying power to the electrical utility power grid when operating in the grid-connect operating mode and for supplying power from the turbogenerator/motor when operating in the stand-alone operating mode; wherein the controller monitors the electrical utility power grid to detect loss of grid power, automatically transitions the pulse width modulated inverter from the grid-connect operating mode to the stand-alone operating mode, and controls the isolating device to disconnect the protected load from the electrical utility power grid.
Claim 38
Independent Claim
175 words
A system for controlling a permanent magnet turbogenerator/motor to transition between a grid-connect operating mode in which the permanent magnet turbogenerator/motor is connected in parallel with an electrical utility power grid, and a stand-alone mode in which the permanent magnet turbogenerator/motor is, disconnected from the electrical utility power grid, the system comprising: an isolating device for controllably connecting and disconnecting a protected load and the turbogenerator/motor to the electrical utility power grid; a controller in communication with the controllable isolating device, the controller including a configurable pulse width modulated inverter operably associated with the permanent magnet turbogenerator/motor for supplying power to the electrical utility power grid when operating in the grid-connect operating mode and for supplying power from the turbogenerator/motor when operating in the stand-alone operating mode; wherein the controller monitors the electrical utility power grid to detect loss of grid power, automatically transitions the pulse width modulated inverter from the grid-connect operating mode to the stand-alone operating mode, and controls the isolating device to disconnect the protected load from the electrical utility power grid.
Claim 39
Dependent Claim
52 words
The system of claim 33 wherein the controller monitors the electric utility power grid to determine a phase rotation sequence and controls the pulse width modulated inverter to synchronize phase rotation sequence of the turbogenerator/motor with the phase rotation sequence of the electric utility power grid prior to transitioning between operating modes.
Claim 40
Dependent Claim
52 words
The system of claim 33 wherein the controller monitors the electric utility power grid to determine a phase reference angle and controls the pulse width modulated inverter to synchronize phase reference angle of the turbogenerator/motor with the phase reference angle of the electric utility power grid prior to transitioning between operating modes.
Claim 41
Dependent Claim
27 words
The system of claim 33 wherein the controller modifies the rotation sequence of power generated by the turbo generator/motor based on a received phase rotation sequence command.
Claim 42
Dependent Claim
29 words
The system of claim 36 wherein the controller modifies the rotation sequence based on a received phase rotation sequence command only if the turbogenerator/motor is operating in stand-alone mode.
Claim 43
Dependent Claim
28 words
The system of claim 36 wherein the controller controls the pulse width modulated inverter to provide a positive phase rotation sequence for the power generated by the turbogenerator/motor.
Claim 44
Dependent Claim
28 words
The system of claim 36 wherein the controller controls the pulse width modulated inverter to provide a negative phase rotation sequence for the power generated by the turbogenerator/motor.
Claim 45
Dependent Claim
59 words
The system of claim 33 wherein the controller operates with resynchronization to resynchronize power generated by the turbogenerator/motor and the electric utility grid when transitioning from the stand-alone operating mode to the grid-connect operating mode and without stop and automatic restart functions such that the turbogenerator/motor does not stop and then automatically restart during a transition between operating modes.
Claim 46
Dependent Claim
18 words
The system of claim 33 wherein the controller operates without resynchronization and without stop and automatic restart functions.
Claim 47
Dependent Claim
18 words
The system of claim 33 wherein the controller operates without resyncrhonization and with stop and automatic restart functions.
Claim 48
Independent Claim
106 words
A method for controlling a permanent magnet turbogenerator/motor to automatically transition between a grid-connect operating mode in which the turbogenerator/motor is connected in parallel with an electrical utility power grid, and a stand-alone mode in which the permanent magnet turbogenerator/motor is disconnected from the electrical utility power grid, the method comprising: monitoring the electrical utility power grid to detect a rotation sequence for power generated by the electrical utility; and controlling the turbogenerator/motor to synchronize a rotation sequence of the turbogenerator/motor with the rotation sequence of the power generated by the electrical utility prior to transitioning between the grid-connect operating mode and the stand-alone operating mode.
Claim 49
Independent Claim
106 words
A method for controlling a permanent magnet turbogenerator/motor to automatically transition between a grid-connect operating mode in which the turbogenerator/motor is connected in parallel with an electrical utility power grid, and a stand-alone mode in which the permanent magnet turbogenerator/motor is disconnected from the electrical utility power grid, the method comprising: monitoring the electrical utility power grid to detect a rotation sequence for power generated by the electrical utility; and controlling the turbogenerator/motor to synchronize a rotation sequence of the turbogenerator/motor with the rotation sequence of the power generated by the electrical utility prior to transitioning between the grid-connect operating mode and the stand-alone operating mode.
Claim 50
Dependent Claim
43 words
The method of claim 43 further comprising: monitoring the electrical utility power grid to determine a phase reference angle; and synchronizing the phase reference angle of power generated by the turbogenerator/motor with the determined phase reference angle of the electrical utility power grid.
Claim 51
Dependent Claim
20 words
The method of claim 43 wherein the step of controlling comprises controlling the turbogenerator/motor to provide a positive rotation sequence.
Claim 52
Dependent Claim
20 words
The method of claim 43 wherein the step of controlling comprises controlling the turbogenerator/motor to provide a negative rotation sequence.
Claim 53
Dependent Claim
26 words
The method of claim 43 further comprising: receiving a rotation sequence command; and controlling the rotation sequence of the turbogenerator/motor based on the rotation sequence command.
Claim 54
Dependent Claim
25 words
The method of claim 47 wherein the step of controlling the rotation sequence is performed only when the turbogenerator/motor is operating in the stand-alone mode.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2005-06-24 | 2005-12-24 | 2006-06-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2009-06-24 | 2009-12-24 | 2010-06-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2013-06-24 | 2013-12-24 | 2014-06-25 | $7700.00 | Window Closed / Lapsed |