Systems and methods for optimal power flow on a radial network

Patent metadata

Field	Value
Publication number	US-9954362-B2
Application number	US-201514722075-A
Country	US
Kind code	B2
Filing date	May 26, 2015
Priority date	May 23, 2014
Publication date	Apr 24, 2018
Grant date	Apr 24, 2018

Abstract

Node controllers and power distribution networks in accordance with embodiments of the invention enable distributed power control. One embodiment includes a node controller including a distributed power control application; a plurality of node operating parameters describing the operating parameter of a node and a set of at least one node selected from the group consisting of an ancestor node and at least one child node; wherein send node operating parameters to nodes in the set of at least one node; receive operating parameters from the nodes in the set of at least one node; calculate a plurality of updated node operating parameters using an iterative process to determine the updated node operating parameters using the node operating parameters that describe the operating parameters of the node and the set of at least one node, where the iterative process involves evaluation of a closed form solution; and adjust node operating parameters.

First claim

What is claimed is:

1. A node controller, comprising:
a network interface;
a processor;
a memory containing:
a distributed power control application and a plurality of node operating parameters;
wherein the distributed power control application, when executed by the processor, is configured to:
model a power distribution network as a radial network comprising a plurality of nodes and lines connecting the nodes, wherein node controllers are associated with processing nodes among the plurality of nodes, and the plurality of nodes include at least one of power stations, substations, distributed power generation, and end user loads, and wherein the lines of the radial network include transmission and distribution lines, and the plurality of nodes in the radial network comprise at least one ancestor node and at last one child node;
calculate an optimal power flow for the power distribution network by performing a closed form solution that creates sub-problems solved concurrently by the node controllers of the processing nodes using the node operating parameters that include power injections, voltages, load impedances, branch currents, and branch power flows of the power distribution network that are determined by the node controllers of the processing nodes;
wherein creating sub-problems comprises decoupling nodes and partitioning the radial network into even and odd layers, and wherein solving the sub-problems further comprises using an iterative process of alternating method of multipliers (ADMM) comprising minimizing an augmented Lagrangian for an augmented relaxed optimal power flow (ROPF) expression in the closed form solution to calculate updated node operating parameters using the determined node operating parameters which are sent and received as requested and required between the node controller and its ancestor and children nodes for the concurrent solving;
and
perform at least one of changing voltages in the power distribution network, redistributing bulk power in the power distribution network, and controlling power or voltage injections to the power distribution network, based on the optimal power flow calculation.

2. The node controller of claim 1 , wherein the ADMM process further comprises an x-update process, wherein the x-update process comprises minimizing an augmented Lagrangian for an augmented Relaxed Optimal Power Flow (ROPF) expression.

3. The node controller of claim 2 , wherein the x-update process is subject to the following constraints:

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Assignees

• California Inst Of Techn

Inventors

• Low Steven H
• Peng Qiuyu

Classifications

• H04L12/6418 Primary

  Hybrid transport · CPC title

• G05B15/02

  electric · CPC title

• G06F17/10

  Complex mathematical operations {(function generation by table look-up G06F1/03; evaluation of elementary functions by calculation G06F7/544)} · CPC title

• H02J3/00 Primary

  Circuit arrangements for AC mains or AC distribution networks · CPC title

• Y02B70/30

  Systems integrating technologies related to power network operation and communication or information technologies for improving the carbon footprint of the management of residential or tertiary loads, i.e. smart grids as climate change mitigation technology in the buildings sector, including also the last stages of power distribution and the control, monitoring or operating management systems at local level · CPC title