Hierarchical DER Control for Demand Response Power Limits
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Managing decentralized distributed energy resources (DERs) in a power grid during demand response events is challenging due to the need for precise control to avoid exceeding maximum power thresholds while maintaining quality of service and minimizing energy costs, especially since traditional methods lack individual household feedback and centralized control efficiency.
Innovation Solution
A power grid management system with a central controller and edge controllers that communicate through uniform messages to adjust energy usage of DERs such as air conditioners and electric water heaters, allowing for two-way communication to aggregate feedback and adjust energy consumption dynamically based on grid service requirements, ensuring efficient load management and cost optimization.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a central controller manages all DERs directly, then control precision is improved, but communication bandwidth requirements increase and system complexity increases
Solution Approach 1:
The system divides the control function into two segments: a central controller that determines power references and sends uniform adjustment messages to all edge controllers, and edge controllers that receive these messages and adjust their local DERs. This segmentation allows precise centralized control decisions while reducing communication bandwidth requirements by using uniform messages instead of individualized control signals for each DER.
Solution Approach 2:
The system introduces a hierarchical dimension to the control architecture, with the central controller operating at one level (determining power references) and edge controllers operating at another level (adjusting local DERs based on uniform messages). This dimensional change allows the system to achieve precise control without requiring proportional communication bandwidth for each individual DER.
2Reliability
If individualized control messages are sent to each DER, then control effectiveness is improved, but communication bandwidth consumption increases
Solution Approach 1:
The uniform adjustment message serves multiple functions simultaneously: it conveys the power reference from the central controller, provides control instructions to all edge controllers, and enables coordinated DER management across the entire system. This universal message format maintains control effectiveness while minimizing communication bandwidth consumption by eliminating the need for individualized messages for each DER.
Solution Approach 2:
The system merges all control instructions into a single uniform adjustment message that is broadcast to all edge controllers. This message combines the power reference information and control directives into one communication event, achieving effective control across all DERs while consuming minimal communication bandwidth compared to sending separate individualized messages.
3Speed
If centralized control is implemented without feedback aggregation, then control speed is improved, but control accuracy deteriorates
Solution Approach 1:
The system implements a feedback mechanism where edge controllers send aggregated feedback data to the central controller about their local DER status and energy usage. The central controller aggregates this feedback information and uses it to adjust future uniform adjustment messages, ensuring control accuracy is maintained while preserving the speed advantage of centralized control by avoiding iterative individualized adjustments.
Data Source
AI summary
Power grid management systems and methods include determining a power reference, and sending a first message from a first controller to each of a plurality of second controllers based on the power reference. Each of the plurality of second controllers is configured to control a plurality of associated distributed energy resources (DERs). Energy usage of the associated DERs is modified by each of the plurality of second controllers based on the first message. Each of the second controllers sends feedback data to the first controller message based on the modified energy usage of the associated DERs. The feedback data is aggregated by the first controller, and the aggregated feedback data is compared to the power reference. The first controller sends a second message to each of the plurality of second controllers based on the comparison.