Reference current generation in bidirectional power converter

• US 9,621,063 B2
• Filed: 03/11/2015
• Issued: 04/11/2017
• Est. Priority Date: 03/11/2015
• Status: Active Grant

• Current Assignee: DRS Naval Power Systems, Inc. (Leonardo S.p.A.), University of Connecticut (State of Connecticut)
• Original Assignee: DRS Consolidated Controls, Inc. (Leonardo S.p.A.)
• Inventors: Ramsay, Scott, Kelley, Michael, Tarca, Matthew, Thompson, John, Gellis, David, Parsons, Thomas, Park, Sung Yeul, Park, Sungmin
• Primary Examiner(s): Tran, Nguyen
• Application Number:
  US14/645,346
• Publication Number:
  US 20160268916A1
• Time in Patent Office: 762 Days
• Field of Search: 363 34, 363 37, 363131, 363157, 363159
• CPC Class Codes: B60L 1/00 Supplying electric power to auxiliary equipment of vehicles circuit arrangements for charging batteries H02J7/00
• CPC Class Codes: B60L 2210/30 AC to DC converters
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 53/14 Conductive energy transfer
• CPC Class Codes: B60L 55/00 Arrangements for supplying energy stored within a vehicle to a power network, i.e. vehicle-to-grid [V2G] arrangements
• CPC Class Codes: H02M 1/007 Plural converter units in cascade push-pull DC/DC converters with pre-regulator H02M3/3374; DC-AC converters following a DC-DC stage including a high frequency transformer H02M7/4807; DC-AC converters following a DC-DC conversion stage generating periodically varying voltages H02M7/4826
• CPC Class Codes: H02M 1/14 Arrangements for reducing ripples from dc input or output
• CPC Class Codes: H02M 1/42 Circuits or arrangements for compensating for or adjusting power factor in converters or inverters
• CPC Class Codes: H02M 5/458 using semiconductor devices only
• CPC Class Codes: H02M 7/4807 having a high frequency intermediate AC stage
• CPC Class Codes: H02M 7/79 using devices of a triode or transistor type requiring continuous application of a control signal
• CPC Class Codes: H04L 1/205 jitter monitoring
• CPC Class Codes: H04L 43/087 Jitter
• CPC Class Codes: H04W 16/18 Network planning tools
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition
• CPC Class Codes: H04W 28/02 Traffic management, e.g. flow control or congestion control
• CPC Class Codes: H04W 48/18 Selecting a network or a communication service
• CPC Class Codes: H04W 72/04 Wireless resource allocation
• CPC Class Codes: H04W 72/12 Wireless traffic scheduling
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
• CPC Class Codes: Y02E 60/00 : Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
• CPC Class Codes: Y02T 10/70 : Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 : Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 10/72 : Electric energy management in electromobility
• CPC Class Codes: Y02T 90/14 : Plug-in electric vehicles
• CPC Class Codes: Y04S 10/126 : the energy generation units being or involving electric vehicles [EV] or hybrid vehicles [HEV], i.e. power aggregation of EV or HEV, vehicle to grid arrangements [V2G]

Abstract

A power converter can be controlled to generate a target output power based on a reactive power reference and an active power reference. The control process may include monitoring a time-varying power signal (e.g., a power grid voltage signal from a power grid), and filtering the time-varying power signal to derive a filtered sine component of the time-varying power signal and a filtered cosine component of the time-varying power signal. A sine coefficient and cosine coefficient each based on at least the reactive power reference and the active power reference can be determined, and applied to the filtered sine component and filtered cosine component of the time-varying power signal, respectively. A target current reference of the power converter can then be set to include a sum of the current reference sine component and the current reference cosine component.

Claims

1. A method for controlling a power converter to generate a target output power, the method comprising:

monitoring a time-varying power signal;

filtering the time-varying power signal to derive a filtered sine component of the time-varying power signal and a filtered cosine component of the time-varying power signal;

determining a sine coefficient based on at least an addition of a reactive power reference term and an active power reference term;

determining a cosine coefficient based on at least a difference between the reactive power reference term and the active power reference term;

applying the sine coefficient to the filtered sine component of the time-varying power signal to derive a current reference sine component;

applying the cosine coefficient to the filtered cosine component of the time-varying power signal to derive a current reference cosine component; and

setting a target current reference of the power converter to include a sum of the current reference sine component and the current reference cosine component.

2. The method of claim 1, wherein the power signal is filtered by a Kalman filter.

3. The method of claim 1, further comprising:

providing the target current reference to a proportional integral (PI) controller to derive a switching duty cycle of the power converter.

4. The method of claim 1, further comprising:

providing the target current reference to a predictive current controller to derive a switching duty cycle of the power converter.

5. The method of claim 1, wherein the sine coefficient and the cosine coefficient are determined further based on an anti-islanding phase disturbance.

6. The method of claim 5, wherein the anti-islanding phase disturbance is from a slip-mode frequency shift process.

7. The method of claim 1, wherein the sine coefficient and the cosine coefficient are determined further based on a current ripple compensation.

8. The method of claim 1, wherein the sine coefficient and the cosine coefficient are determined by ignoring a current ripple compensation.

9. The method of claim 1, wherein the power signal is a grid voltage signal from a power grid.

10. The method of claim 9, wherein the power converter is operable to inject power into the power grid.

11. A power converter comprising:

an AC-AC converter; and

a switch controller coupled to the AC-AC converter, the switch controller including;

a synchronization unit configured to monitor a time-varying power signal that the power converter is to synchronize with, and to filter the time-varying power signal to derive a filtered sine component of the time-varying power signal and a filtered cosine component of the time-varying power signal; and

a reference current generator configured to derive a current reference sine component by applying a sine coefficient to the filtered sine component of the time-varying power signal, and a current reference cosine component by applying a cosine coefficient to the filtered cosine component of the time-varying power signal, and generate a target current reference that includes a sum of the current reference sine component and the current reference cosine component,

wherein the sine coefficient is determined based on at least an addition of a reactive power reference term and an active power reference term, and the cosine coefficient is determined based on at least a difference between the reactive power reference term and the active power reference term.

12. The power converter of claim 11, further comprising a proportional integral (PI) controller configured to derive a switching duty cycle of the power converter based on the target current reference.

13. The power converter of claim 11, further comprising a predictive current controller configured to derive a switching duty cycle of the power converter based on the target current reference.

14. The power converter of claim 11, wherein the AC-AC converter includes a cyclo-inverter.

15. The power converter of claim 11, further comprising a DC-AC converter coupled to the AC-AC converter.

16. The power converter of claim 15, wherein the DC-AC converter includes a H-bridge inverter.

17. The power converter of claim 11, further comprising a DC-DC converter coupled to the DC-AC converter.

18. The power converter of claim 17, wherein the DC-DC converter includes a buck-boost circuit.

19. The power converter of claim 11, wherein the power converter is coupled to an electric vehicle battery.