TIDUFE9 August   2025

 

  1.   1
  2.   Description
  3.   Resources
  4.   Features
  5.   Applications
  6.   6
  7. 1System Description
    1. 1.1 Key System Specifications
    2. 1.2 Electricity Meters
    3. 1.3 Circuit Breakers
    4. 1.4 EV Chargers
    5. 1.5 Protection and Relay
    6. 1.6 Rogowski Coil-Based Current Sensor
      1. 1.6.1 Principle
      2. 1.6.2 Rogowski Coil Types
      3. 1.6.3 Integration Methods
      4. 1.6.4 Rogowski Coil Selection
  8. 2System Overview
    1. 2.1 Block Diagram
      1. 2.1.1 Differential Gain Amplifier
      2. 2.1.2 High-Pass Filter
      3. 2.1.3 Low-Pass Filter
      4. 2.1.4 Active Integrator
    2. 2.2 Design Considerations
      1. 2.2.1 Components Selection
        1. 2.2.1.1 RC Component Selection
        2. 2.2.1.2 RG Selection for Gain Setting
    3. 2.3 Highlighted Products
      1. 2.3.1 INA828
      2. 2.3.2 TLV9001
      3. 2.3.3 LM27762
  9. 3System Design Theory
    1. 3.1 Schematics to Layout
      1. 3.1.1 Rogowski Input Connectors
      2. 3.1.2 Gain Setting Resistor Chain
      3. 3.1.3 Gain Amplifier and High-Pass Filter Stage
      4. 3.1.4 Active Integrator Stage
      5. 3.1.5 Output Stage
      6. 3.1.6 Power Supply
  10. 4Hardware, Testing Requirements, and Test Results
    1. 4.1 Hardware Requirements
    2. 4.2 Test Setup
      1. 4.2.1 Full System Block Diagram
      2. 4.2.2 Test System
      3. 4.2.3 Rogowski Coil
      4. 4.2.4 TIDA-010986
      5. 4.2.5 ADS131M08 Metrology Evaluation Module
      6. 4.2.6 GUI
        1. 4.2.6.1 Getting Started
          1. 4.2.6.1.1 PCB Rogowski Coil Setup
          2. 4.2.6.1.2 TIDA-010986 Connectors
            1. 4.2.6.1.2.1 Input Terminal Block
            2. 4.2.6.1.2.2 Power Connection
            3. 4.2.6.1.2.3 Output Connections
          3. 4.2.6.1.3 ADS131M08 Metrology Evaluation Module Connectors
    3. 4.3 Test Results
      1. 4.3.1 Functional Test
      2. 4.3.2 Accuracy Measurements
        1. 4.3.2.1 No Load Conditions
          1. 4.3.2.1.1 Objective
          2. 4.3.2.1.2 Setup
          3. 4.3.2.1.3 Requirements
          4. 4.3.2.1.4 Results
        2. 4.3.2.2 Initial Load Operation Test
          1. 4.3.2.2.1 Objective
          2. 4.3.2.2.2 Setup
          3. 4.3.2.2.3 Requirements
          4. 4.3.2.2.4 Results
        3. 4.3.2.3 Accuracy Test at Different Load Conditions
          1. 4.3.2.3.1 Objective
          2. 4.3.2.3.2 Setup
          3. 4.3.2.3.3 Requirements
          4. 4.3.2.3.4 Results
        4. 4.3.2.4 Variation of Power Factor Test
          1. 4.3.2.4.1 Objective
          2. 4.3.2.4.2 Setup
          3. 4.3.2.4.3 Requirements
          4. 4.3.2.4.4 Results
        5. 4.3.2.5 Variation of Voltage Test
          1. 4.3.2.5.1 Objective
          2. 4.3.2.5.2 Setup
          3. 4.3.2.5.3 Requirements
          4. 4.3.2.5.4 Results
        6. 4.3.2.6 Variation of Frequency Test
          1. 4.3.2.6.1 Objective
          2. 4.3.2.6.2 Setup
          3. 4.3.2.6.3 Requirements
          4. 4.3.2.6.4 Results
        7. 4.3.2.7 Phase Sequence Reversal Test
          1. 4.3.2.7.1 Objective
          2. 4.3.2.7.2 Setup
          3. 4.3.2.7.3 Requirements
          4. 4.3.2.7.4 Results
  11. 5Design and Documentation Support
    1. 5.1 Design Files
      1. 5.1.1 Schematics
      2. 5.1.2 BOM
      3. 5.1.3 Layout Prints
    2. 5.2 Tools
    3. 5.3 Documentation Support
    4. 5.4 Support Resources
    5.     Trademarks
  12. 6About the Author

Description

This reference design is a signal conditioning reference design for Rogowski coils, targeting enhanced accuracy for current measurement in e-meters, circuit breakers, protection relays, and EV chargers enabling Rogowski coil measurements to meet ANSI C12.1 and IEC compliance standards. This op-amp-based active integrator design covers a wide dynamic current range with bandwidth, stability, and adjustable gain (1V/V to 525V/V). The design is optimized for three-phase systems and interfaces with TI's ADS131M08 Metrology Evaluation Module. The design aims to achieve current transformer-like accuracy at a cost similar to shunt-based designs and also meet class 0.2 and better accuracy levels compared to a current transformer (CT) without a magnetic core.