Isolation Transformer Voltage Sensing Without Extra Galvanic Isolation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Industrial control products face challenges in determining input voltage to a galvanic isolation point in hazardous and noisy environments without requiring additional galvanic isolation points, which increases costs and board space.
Innovation Solution
The solution involves using an isolation transformer to conduct a primary current and provide a secondary voltage proportional to the primary voltage, coupled with a peak detection circuit to receive and process the secondary voltage, allowing for the determination of the input voltage without additional isolation points.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If an additional galvanic isolation point (transformer) is added to transmit the measured input voltage value, then the input voltage can be determined on the primary side, but the board space increases and costs increase
Solution Approach 1:
The existing isolation transformer is made to serve dual functions: its primary role of electrical isolation and a secondary role of voltage measurement. By tapping the secondary voltage from the existing transformer and processing it through rectification and peak detection circuits, the system determines the input voltage without requiring an additional measurement transformer, thus eliminating the need for extra board space while maintaining measurement capability
Solution Approach 2:
The isolation transformer serves itself by providing both isolation and measurement functions. The secondary voltage generated by the transformer during normal operation is reused for measurement purposes through the peak detection circuit, eliminating the need for separate measurement resources and reducing overall system complexity
2Measurement precision
If an additional galvanic isolation point (transformer) is added to transmit the measured input voltage value, then the input voltage can be determined on the primary side, but the manufacturing costs increase
Solution Approach 1:
The existing isolation transformer is made to serve dual functions: its primary role of electrical isolation and a secondary role of voltage measurement. By tapping the secondary voltage from the existing transformer and processing it through rectification and peak detection circuits, the system determines the input voltage without requiring an additional measurement transformer, thus eliminating the need for extra board space while maintaining measurement capability
Solution Approach 2:
The measurement function is merged with the existing isolation transformer rather than being implemented as a separate component. The secondary winding of the isolation transformer provides the measurement signal, and the peak detection circuit processes this signal to determine the input voltage, combining isolation and measurement functions into a single integrated approach that reduces component count and manufacturing cost
3Measurement precision
If circuits on the secondary side are used to determine the input voltage, then the measurement can be performed, but noise and transients from the primary side may affect the measurement accuracy
Solution Approach 1:
The isolation transformer acts as an intermediary that transfers the voltage information from the primary side to the secondary side while blocking harmful noise and transients. The transformer's galvanic isolation property allows the secondary voltage to be a clean, proportional representation of the primary voltage, free from electrical noise and transient interference that would otherwise affect measurements taken directly on the primary side
Solution Approach 2:
The measurement system replaces direct electrical measurement on the noisy primary side with indirect measurement through the isolated secondary side. By using the transformer ratio relationship and peak detection of the secondary voltage, the system obtains accurate input voltage information without exposing the measurement circuits to electromagnetic interference and noise present on the primary side
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
This approach enables the determination of input voltage to a galvanic isolation point using a single isolation transformer, reducing board space and costs while isolating noise and transients, ensuring accurate voltage measurement.
Implementation Method 1
an isolation transformer configured to conduct a primary current provided by an input voltage source, and provide a secondary voltage, the secondary voltage being proportional to a primary voltage induced by the primary current
Data Source
AI summary
An electronics (100) configured to determine an input voltage to a galvanic isolation point of the electronics (100) is provided. The electronics (100) comprises an isolation transformer (120) configured to conduct a primary current (Ip) provided by an input voltage source (110), and provide a secondary voltage (Vs), the secondary voltage (Vs) being proportional to a primary voltage (Vp) induced by the primary current (Ip). The electronics (100) also comprises a peak detection circuit (130) coupled to the isolation transformer (120), the peak detection circuit (130) being configured to receive the secondary voltage (Vs) and, based on the secondary voltage (Vs), provide a signal that is proportional to the primary voltage (Vp).