Phase Angle Detection Using Shunt Resistor Voltage
Solution Overview
Problem
Traditional phase angle measurements in inverter systems require both load voltage and current values, leading to inconsistent and inaccurate outputs due to nonlinear and phase shifting characteristics of current transducers and voltage dividers, causing inefficiencies in power delivery.
Innovation Solution
A method and system for detecting phase angle directly from a voltage measured across a shunt resistor, allowing the phase angle to be determined between load current and voltage, enabling accurate power delivery adjustments in inverter systems.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional phase angle measurement methods using current transducers and voltage dividers are used, then phase angle detection can be performed, but measurement precision deteriorates due to nonlinear and phase shifting characteristics
Solution Approach 1:
The patent extracts the phase angle detection function from the traditional dual-sensor system (current transducer and voltage divider) and implements it using only voltage sensing across a shunt resistor. This eliminates the problematic current transducer while retaining the essential measurement capability through mathematical derivation of phase angle from voltage waveforms alone.
Solution Approach 2:
The patent replaces the physical current measurement system (current transducer) with an electrical/mathematical approach. By measuring voltage across a shunt resistor and processing the waveform data through computational methods, the system substitutes direct current sensing with voltage-based phase angle calculation, eliminating the source of nonlinear errors.
2Ease of operation
If both load voltage and current values are measured to determine phase difference, then power delivery control can be adjusted, but device complexity increases due to multiple sensors and measurement circuits
Solution Approach 1:
The patent removes the current measurement subsystem from the traditional setup, extracting only the essential voltage measurement function. By using a shunt resistor to sense voltage and deriving phase angle information from voltage waveforms alone, the system eliminates the need for separate current transducers and voltage dividers, significantly simplifying the measurement architecture.
Solution Approach 2:
The shunt resistor serves multiple functions: it provides the measurement point for voltage sensing, acts as a current sense element through voltage drop measurement, and enables phase angle detection. This multi-functional approach replaces the need for dedicated current and voltage sensing components, reducing overall system complexity while maintaining full control capability.
Data Source
AI summary
A system and method of detecting phase angle in an inverter is provided. A shunt resistor is coupled to a controller which is part of an inverter circuit and a phase angle may be directly derived from the detected voltage across the shunt resistor. The detected shunt voltage may be used to adjust the power delivery from the inverter to the load.