AC Network Phase Angle Measurement for Power Accuracy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional non-contact measuring devices for electrical quantities in AC networks face significant measurement errors due to increasing phase differences and voltage fluctuations, especially with renewable energy sources and multi-phase loads, leading to inaccurate active power calculations.
Innovation Solution
A measuring device connected to one phase of the AC network measures the actual voltage and phase angles, allowing for the derivation of phase differences between current and voltage across all phases, enabling precise determination of active and reactive power with minimal intervention in the wiring.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If conventional non-contact measuring devices are used to measure current and calculate apparent power, then the measurement process is simple and requires minimal intervention, but the measurement precision deteriorates due to phase differences and voltage fluctuations
Solution Approach 1:
The patent introduces a measuring device that acts as an intermediary between the AC network and the measurement process. This device directly measures voltage and phase angles in the network, using these measurements as intermediate variables to calculate active power, thereby avoiding the errors that occur when assuming constant voltage and zero phase difference
Solution Approach 2:
The patent changes the measurement parameters from merely current magnitude to including phase angles and actual voltage measurements. By measuring the phase angle between current and voltage directly, the system adapts to varying network conditions and calculates active power using the actual phase difference rather than assuming it is zero
2Measurement precision
If the measuring device directly measures voltage and phase angles in the AC network, then the measurement precision of active power improves, but the device complexity increases due to additional measurement requirements
Solution Approach 1:
The measuring device is designed to perform multiple functions: it measures current magnitude, voltage magnitude, and phase angles simultaneously. By integrating these measurement capabilities into a single device, the patent avoids the need for separate measurement systems, thereby reducing overall system complexity while maintaining high measurement precision
3Device complexity
If conventional measuring devices assume constant voltage and zero phase difference, then the device complexity is minimized, but the reliability of measurement results deteriorates under varying network conditions
Solution Approach 1:
The patent transitions from a static measurement approach (assuming constant voltage and zero phase difference) to a dynamic approach where voltage and phase angles are continuously measured and updated. This allows the measuring device to adapt to changing network conditions, maintaining reliability even when renewable energy sources cause voltage fluctuations and phase differences
Data Source
Figure 1
Figure 2a~2b
Figure 2c~2d
AI summary
Method for recording an electrical quantity of a consumer connected to an AC power network, in which a measuring device with at least one supply connection is connected to at least one phase of the AC power network and is electrically supplied, and with the aid of the measuring device a phase angle of the supply voltage is measured at the supply connection, a phase angle of the current in the respective phases of the lines of the AC power network connected to the consumer is measured at at least two measuring connections of the measuring device, and the respective measured phase angles of the current are evaluated with the measured phase angle of the supply voltage.