Microgrid Operating Point Shift Control for Forecast Deviations

Solution Overview

Problem

Microgrid control systems face challenges in maintaining optimal operating points due to inaccuracies in forecast variables, leading to power imbalances and non-optimal operations when actual values deviate from forecasted values.

Innovation Solution

A method that introduces an 'operating point shift value' calculated as a derivative of the operating point with respect to forecast variables, allowing for updates to the operating points of controllable assets in a microgrid when actual values differ from forecasted values, ensuring robustness and maintaining power balance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If forecast variable values are used to determine operating point values, then optimal operation is achieved, but reliability deteriorates when actual values deviate from forecasted values

Engineering Contradiction:

Improveoptimal operationVSAvoidrobustness against forecast inaccuracies

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The patent pre-calculates operating point shift values (sensitivity coefficients) in advance that represent how operating points change in response to forecast errors. These pre-computed shift values are stored and ready for immediate application when actual values deviate from forecasts, enabling rapid compensation without real-time complex calculations.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system implements a feedback mechanism where the difference between actual and forecasted values is continuously monitored. When deviations are detected, the pre-calculated operating point shift values are applied to adjust operating points, creating a closed-loop control system that automatically compensates for forecast inaccuracies.

Inventive Principle:

Principle #23Feedback

2Reliability

If operating point values are updated in real-time based on forecast deviations, then reliability is improved, but device complexity increases

Engineering Contradiction:

Improverobustness against forecast inaccuraciesVSAvoidcomputational complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent pre-calculates operating point shift values (sensitivity coefficients) in advance that represent how operating points change in response to forecast errors. These pre-computed shift values are stored and ready for immediate application when actual values deviate from forecasts, enabling rapid compensation without real-time complex calculations.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system changes the parameter representation from full operating point recalculations to simplified shift values (sensitivity coefficients). By working with these transformed parameters that capture the essential relationships, the system achieves robustness with reduced computational complexity.

Inventive Principle:

Principle #35Parameter changes

3Productivity

If forecast-based operating points are used, then power balance is optimized, but loss of energy increases due to power imbalances when forecasts are incorrect

Engineering Contradiction:

Improvepower balance optimizationVSAvoidpower imbalance losses

Core Design Contradiction:

ProductivityVSLoss of energy

Solution Approach 1:

The system implements a feedback mechanism where the difference between actual and forecasted values is continuously monitored. When deviations are detected, the pre-calculated operating point shift values are applied to adjust operating points, creating a closed-loop control system that automatically compensates for forecast inaccuracies.

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

The patent converts the potentially harmful effect of forecast errors into a beneficial adaptation mechanism. By pre-calculating how operating points should shift in response to various forecast deviations, the system transforms forecast inaccuracies from a source of power imbalance into an opportunity for adaptive compensation, thereby reducing energy losses.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

Data Source

PatentEP3700043B1Method of controlling a microgrid, power management system, and energy management system

Publication Date: 2023.12.06 HITACHI ENERGY LTD

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AI summary

A method of controlling a microgrid (10) comprises retrieving, by an energy management system, EMS (50), a forecast variable value for a forecast variable. The EMS (50) determines an operating point value for a controllable asset (11-14) that depends on the retrieved forecast variable value. The EMS (50) determines an operating point shift value for the controllable asset (11-14), the operating point shift value representing a shift in operating point value in response to a variation in forecast variable value. The operating point value and the operating point shift value are provided to a power management system, PMS (40), of the microgrid (10).