Islanding Detection Disablement for Microgrid Power Continuity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In power systems, islanding detection functions can prevent power source devices from operating independently in microgrids disconnected from the main power system, leading to a lack of power supply during emergencies, as existing detection schemes like frequency feedback with step injection can cause devices to disconnect from the grid even when safety is confirmed, hindering power restoration.
Innovation Solution
The implementation of an electronic apparatus with a controlling circuitry that outputs a disabling signal to cancel frequency changes in the microgrid, allowing power source devices to operate independently and supply power without triggering islanding detection, enabling power supply in disconnected microgrids.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If islanding detection function is activated in power source devices, then safety is improved by detecting unauthorized islanding, but power supply capability deteriorates because devices cannot operate independently in disconnected microgrids
Solution Approach 1:
The islanding detection function is made dynamically controllable through a detection disablement signal that can switch the detection state between enabled and disabled. This allows the system to adapt its behavior based on operational context - enabling detection during normal grid-connected operation for safety, and disabling it during intentional islanded operation to maintain power supply capability.
Solution Approach 2:
The system changes the operational parameter of the islanding detection function from a fixed enabled state to a variable state controlled by the detection disablement signal. By modifying the detection function's operational parameter (enabled/disabled) based on external control signals, the system resolves the contradiction between maintaining safety through detection and enabling power supply through independent operation.
2Measurement precision
If frequency feedback scheme with step injection is used for islanding detection, then detection accuracy is improved, but device operation deteriorates because devices disconnect even when safety is confirmed
Solution Approach 1:
The detection disablement signal provides a preliminary counter-action to the frequency feedback scheme's detection mechanism. By preemptively disabling the detection function when intentional islanding is expected, the system prevents the frequency feedback scheme from triggering false disconnection actions, thereby maintaining device operation while preserving the ability to detect unauthorized islanding when needed.
Solution Approach 2:
The detection disablement signal acts as an intermediary control mechanism between the frequency feedback detection scheme and the device operation. It mediates the interaction by selectively suppressing the detection function's output, allowing the high-accuracy frequency feedback scheme to coexist with stable device operation in intentional islanded scenarios.
3Reliability
If power source devices remain disconnected from the power system, then safety in the microgrid is improved, but power restoration deteriorates because islanding detection prevents independent operation
Solution Approach 1:
The detection disablement signal enables preliminary action by allowing power source devices to operate independently in the microgrid before the main power system is fully restored. By preemptively disabling islanding detection during this intermediate period, the system maintains safety through other means while enabling power restoration activities to proceed without detection-induced disruptions.
Data Source
AI summary
According to one embodiment, an electronic apparatus connectable to a partial power system which is a part of a power system and comprises a first power source apparatus, power supply of the first power source apparatus stopped in response to detecting an islanding of the partial power system, includes: controlling circuitry configured to output to the partial power system a first signal to disable detecting the islanding of the partial power system by the first power source apparatus during at least part of a period during which the partial power system is electrically separated from the power system.