Coordinated control method of generator and SVC for improving power throughput and controller thereof

Patent metadata

Field	Value
Publication number	US-9893524-B2
Application number	US-201214374559-A
Country	US
Kind code	B2
Filing date	Dec 20, 2012
Priority date	Dec 20, 2012
Publication date	Feb 13, 2018
Grant date	Feb 13, 2018

Abstract

The present invention provides coordinated control methods of generator and SVC for improving power plant active power throughput and controller thereof. The method comprises: measuring the required input parameters for the generator and SVC control; judging the system topology and the control mode of SVC to determine the operation mode; and calculating the control reference based on the operation mode to control the generator and/or SVC. The proposed methods and coordinated controllers enable the SVC to share the required reactive power output of the power plant, convert the generator into “unity-power-factor-generator”, and therefore extend the active power output capability of the power plant.

First claim

The invention claimed is:

1. A coordinated control method of a power plant including a generator and a Static Var Compensator (SVC), comprising:
measuring required input parameters for said generator and an SVC control with a coordinated controller for the power plant, wherein the coordinated controller is operative to provide coordinated control of the generator and the SVC;
judging a system topology and a control mode of the SVC control to determine an operation mode with the coordinated controller;
calculating a control reference based on said operation mode to control said generator and/or the SVC control with the coordinated controller; and
operating one or both of the generator and the SVC with the coordinated controller using the control reference so as to increase power plant active power throughput,
wherein said operation mode is divided into four (4) types, wherein a first type of the operation mode is that said SVC is connected to a low voltage side of a unit transformer and said SVC control executes a reactive power control, wherein a second type of the operation mode is that said SVC control is connected to a high voltage side of said unit transformer and said SVC control executes the reactive power control, wherein a third type of the operation mode is that said SVC control is connected to the high voltage side of said unit transformer and said SVC control executes a voltage control, wherein a fourth type of the operation mode is that said SVC control is connected to the low voltage side of said unit transformer and said SVC control executes the voltage control.

2. The coordinated control method according to claim 1 , wherein in said first type of the operation mode, said coordinated control method further comprises:
calculating an SVC reactive power reference according to a generator active power reference, generator reactive power reference, and a unit transformer high side voltage reference;
calculating a generator terminal voltage reference according to the generator active power reference, and the unit transformer high side voltage reference; and
sending said SVC reactive power reference to a local controller of SVC control and said generator terminal voltage reference to an excitation voltage controller of the generator.

3. The coordinated control method according to claim 2 , wherein said generator terminal voltage reference further comprises a generator side feedback component calculated by a generator reactive power closed-loop controller.

4. The coordinated control method according to claim 2 , wherein the SVC reactive power reference and/or an SVC voltage reference further comprises an SVC side feedback component calculated by a generator reactive power closed-loop controller.

5. The coordinated control method according to claim 1 , wherein in said second type of the operation mode, said coordinated control method further comprises:
calculating a generator terminal voltage reference according to generator active power reference, a generator reactive power reference, and a unit transformer high side voltage reference;
calculating an SVC reactive power output reference according to the generator active power reference, the generator reactive power reference, a unit transformer high side voltage reference, and the generator terminal voltage reference, and
sending said SVC reactive power reference to a local controller of SVC and said generator terminal voltage reference to an excitation voltage controller of the generator.

6. The coordinated control method according to claim 1 , wherein in said first type of the operation mode and/or said second type of the operation mode, said coordinated control method further comprises:
setting a generator terminal voltage reference according to unit transformer low side voltage reference;
calculating an SVC reactive power reference according to a generator active power reference, a generator reactive power reference, and a generator terminal voltage reference, and
sending said SVC reactive power reference to a local controller of the SVC and said generator terminal voltage reference to an excitation voltage controller of generator.

7. The coordinated control method according to claim 1 , wherein in said third type of the operation mode, said coordinated control method further comprises:
setting an SVC voltage reference according to a unit transformer high side voltage reference;
calculating a generator terminal voltage reference according to generator active power reference, a generator reactive power reference, and an SVC voltage reference; and
sending said SVC voltage reference to a local controller of the SVC and said generator terminal voltage reference to an excitation voltage controller of the generator.

8. The coordinated control method according to claim 1 , wherein in said third type of the operation mode, said coordinated control method can also comprise:
setting the generator terminal voltage reference according to unit transformer low side voltage reference;
calculating an SVC voltage reference according to a generator active power reference, a generator reactive power reference, and a generator terminal voltage reference, and
sending said SVC voltage reference to a local controller of SVC and said generator terminal voltage reference to an excitation voltage controller of the generator.

9. The coordinated control method according to claim 1 , wherein in said fourth type of the operation mode, said coordinated control method further comprises:
calculating SVC voltage reference according to a generator active power reference and a unit transformer high side voltage reference;
calculating a generator terminal voltage reference according to the generator active power reference and the unit transformer high side voltage reference; and
sending said SVC voltage reference to a local controller of SVC and said generator terminal voltage reference to an excitation voltage controller of generator.

10. The coordinated control method according to claim 9 , wherein said generator terminal voltage reference further comprises a generator side droop component calculated by a generator reactive power droop controller for the fourth type of said operation mode.

11. The coordinated control method according to claim 9 , wherein said SVC voltage reference further comprises an SVC side droop component calculated by an SVC reactive power droop controller for the fourth type of said operation mode.

12. The coordinated control method according to claim 1 , wherein in said fourth type of the operation mode, said coordinated control method can also comprise:
setting an SVC voltage reference according to a unit transformer low side voltage reference;
setting a generator terminal voltage reference according to the unit transformer low side voltage reference; and
sending said SVC voltage reference to a local controller of SVC and said generator terminal voltage reference to an excitation voltage controller of generator.

13. A system comprising:
a generator and a Static Var Compensator (SVC) of a power plant;
a controller, wherein the controller is a coordinated controller operative to provide coordinated control of the generator and the SVC; and
an input/output structured to couple the coordinated controller to said generator and said SVC,
wherein the coordinated controller is configured to measure required input parameters for said generator and an SVC control;
judge a system topology and a control mode of the SVC to determine an operation mode;
calculate a control reference based on said operation mode to control said generator and/or the SVC; and
operate one or both of the

Assignees

• Abb Schweiz Ag

Inventors

• Chen Yao
• Zhang Guoju
• Sao Charles

Classifications

• H02P9/14

  by variation of field (H02P9/08, H02P9/10 take precedence) · CPC title

• Y02E40/12

  Cross-Sectional Technologies · mapped topic

• H02P9/30

  using semiconductor devices · CPC title

• H02J3/18

  Arrangements for adjusting, eliminating or compensating reactive power in networks · CPC title

• H02J3/1821 Primary

  using shunt compensators · CPC title