Two-level predictive based reactive power coordination and voltage restoration for microgrids

Patent metadata

Field	Value
Publication number	US-10333308-B2
Application number	US-201715635928-A
Country	US
Kind code	B2
Filing date	Jun 28, 2017
Priority date	Aug 15, 2016
Publication date	Jun 25, 2019
Grant date	Jun 25, 2019

Abstract

A computer-implemented method for controlling voltage fluctuations of a microgrid including a plurality of distributed generators (DGs) is presented. The computer-implemented method includes collecting, by a resiliency controller, measurement data from the microgrid, using a model predictive control (MPC) module to distribute reactive power to each of the DGs of the microgrid, and using a droop based controller to guide operation of each of the DGs of the microgrid.

First claim

What is claimed is:

1. A computer-implemented method executed on a processor for controlling voltage fluctuations of a microgrid including a plurality of distributed generators (DGs), the method comprising:
collecting, by a resiliency controller, measurement data from the microgrid, the resiliency controller including a voltage control module having a droop-based local control level and a model predictive control (MPC) based global control level;
determining, at the MPC based global control level, optimal reactive power set points of each of the DGs based on reactive power availability;
transmitting the optimal reactive power set points of each of the DGs, via a communication interface, to the droop-based local control level; and
regulating, at the droop-based local control level, via the plurality of DGs, reactive power output through droop-based tracking;
wherein the MPC based global control level enables voltage sensitivity factor determination, prediction model estimation, and MPC model formulation.

2. The method of claim 1 , wherein the resiliency controller further includes a frequency control module and a mode switching module.

3. The method of claim 2 , wherein the voltage control module is executed by a reactive power distribution algorithm for distributing the reactive power to each of the DGs of the microgrid.

4. The method of claim 2 , wherein the frequency control module utilizes a droop based controller to regulate a microgrid frequency.

5. The method of claim 2 , wherein the mode switching module controls microgrid operation status transition between grid-tied mode and islanded mode.

6. The method of claim 1 , wherein, at MPC based global control level, voltage sensitivity factors are used to estimate a relationship between reactive power change and voltage change for each of the DGs of the microgrid.

7. The method of claim 6 , wherein a prediction model for each of the DGs of the microgrid is estimated to predict a behavior of an energy management system in communication with the microgrid via the resiliency controller.

8. The method of claim 6 , wherein the voltage sensitivity factors involve power flow calculations given by:

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Assignees

• Nec Lab America Inc
• Nec Corp

Inventors

• Guo Feng
• Sharma Ratnesh
• Wang Siqi

Classifications

• H02J3/003

  Load forecast, e.g. methods or systems for forecasting future load demand · CPC title

• H02J2103/30

  Simulating, planning, modelling, reliability check or computer assisted design [CAD] of electric power networks · CPC title

• H02J2101/28

  Wind energy · CPC title

• H02J2101/25

  involving maximum power point tracking control for photovoltaic sources · CPC title

• H02J2101/24

  Photovoltaics · CPC title