Detecting High Impedance in Electrical Grids Using Smart Meter Statistics
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
High impedance connections in electrical grids due to poor conductivity and unmetered loads lead to energy losses and unsafe wiring conditions, causing financial losses and voltage problems for utility companies.
Innovation Solution
Implementing a smart electrical grid system that uses smart meters and a central or back office to calculate impedance and voltage at transformer secondaries, identifying high impedance situations and power diversion by repeatedly measuring voltage and current, and applying statistical methods to detect anomalies over time.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If current is drawn through a high impedance connection, then voltage drop and heating occur, but the connection deteriorates further causing even higher impedance
Solution Approach 1:
The system performs preliminary detection of high impedance conditions by analyzing voltage and current measurements before significant deterioration occurs. By calculating impedance values and comparing them against thresholds, the system identifies problematic connections early in their degradation process, enabling preventive maintenance before the connections fail completely or cause safety hazards.
Solution Approach 2:
The system continuously monitors impedance values and provides feedback about connection conditions. By repeatedly measuring voltage and current at multiple locations and calculating impedance, the system tracks the progression of connection deterioration over time, allowing utility companies to respond to worsening conditions and take corrective action.
2Loss of energy
If traditional billing procedures are used, then metered loads are billed normally, but unmetered loads result in energy theft without detection
Solution Approach 1:
The system adds a new dimension to traditional billing by incorporating impedance analysis alongside conventional metering. Instead of relying solely on energy consumption measurements, the system measures voltage and current to calculate impedance values, creating an additional diagnostic dimension that reveals connection conditions and potential theft without requiring complex new hardware at customer premises.
Solution Approach 2:
The system serves multiple functions using the same measurement infrastructure. The same voltage and current measurements used for traditional billing and energy calculation are also used to detect high impedance conditions and potential energy theft. This multi-functionality allows the system to address both legitimate billing and security concerns without adding separate measurement systems.
3Measurement precision
If impedance is calculated at multiple locations and times, then high impedance conditions can be detected, but data processing complexity increases
Solution Approach 1:
The system segments the electrical grid into multiple measurement locations and time intervals, calculating impedance independently at each segment. By dividing the overall detection task into discrete location-specific and time-specific calculations, the system achieves comprehensive coverage and high detection accuracy while keeping individual calculations simple and manageable.
Solution Approach 2:
The system performs impedance calculations at more locations and times than strictly necessary for basic detection. By collecting excessive measurement data across the grid, the system ensures that high impedance conditions are detected even when they occur intermittently or at locations with lower measurement frequency, thereby improving detection reliability.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Effectively detects high impedance conditions and energy diversion, reducing energy losses and financial losses for utility companies by identifying and addressing issues such as poor connections and unauthorized loads, thereby improving grid efficiency and safety.
Implementation Method 1
an impedance value is calculated as a change in two voltage measurements divided by a change in two current measurements
Implementation Method 2
When current is drawn through a high impedance connection, there is a voltage drop across the connection
Implementation Method 3
When current is drawn through a high impedance connection, there is a voltage drop across the connection and associated heating
Data Source
AI summary
Techniques for detecting high impedance conditions in an electrical grid are described herein. In one example, impedance is calculated for each of a plurality of locations within the electrical grid, such as at electrical meters. The impedances may be calculated as a change in voltage divided by a change in current, such as between sequential voltage/current measurements. Statistics may be maintained, including the calculated impedances. In three examples, statistics may be used to identify growth in impedance over multiple days, to identify growth in impedance over multiple hours, and to identify a meter for which impedance is higher than impedance for other meters attached to a single transformer. In a further example, instances of impedance over a threshold value may be identified, from among the maintained statistics. The instances of high impedance may be reported for reasons including cost and safety.