SBOA624 March   2025 TMCS1123 , TMCS1126 , TMCS1127 , TMCS1133

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Solar Application Scenarios with Hall-effect Current Sensing
    1. 2.1 String Inverter
      1. 2.1.1 String Current Sampling
      2. 2.1.2 Arc Current Detection (Optional)
      3. 2.1.3 MPPT Boost Current Sampling
      4. 2.1.4 3-Phase Current Sampling
    2. 2.2 Single-Phase Residential Inverter
    3. 2.3 3-Phase Hybrid Inverter
      1. 2.3.1 BDC Current Sampling
      2. 2.3.2 Off-Grid EPS 3-Phase Current Sampling
      3. 2.3.3 Neutral Current Sampling for Midpoint Potential Balancing
    4. 2.4 Split-Phase Hybrid Inverter
    5. 2.5 Micro Inverter
    6. 2.6 Solar Power Optimizer
    7. 2.7 Smart Combiner Box of Central Inverter
    8. 2.8 Summary of Solar Inverter System and In-package Hall-effect Current Sensor
  6. 3Summary
  7. 4References

1 Introduction

Current measurement accuracy and reliability is critical to solar inverter system, because this determines the control accuracy of the power stage and further affects the energy harvest efficiency. For high-voltage solar inverter systems, through-hole board mount hall-effect current sensor (or for example, magnetic current sensor) have intrinsic isolation nature and the measurement does not intervene the measured circuit that provides wiring and installation convenience.

Close-loop hall-effect current sensor can provide high accuracy, fast response, low sensitivity and low non-linearity error, the sensor needs extra magnetic core, coil and high-power amplifier to drive the coil that makes close-loop hall-effect current sensor has more complex structure, large size, higher power consumption and higher cost than those of open-loop hall-effect current sensor. So, considering the tradeoff between performance and complexity, open-loop through-hole board mount hall-effect current sensor have been widely used in solar inverter system for a long time.

However, open-loop through-hole hall-effect current sensor usually cannot achieve high accuracy over both lifetime and temperature. Meanwhile, this is easy to fail during the installation and transportation processes due to the brittle magnetic core damage, which reduces the system reliability. This can be great if open-loop hall-effect current sensor can provide sufficient performance of accuracy, response, sensitivity, and non-linearity as close-loop one. The better option is using in-package hall-effect current sensor such as TMCS112x and TMCS113x. TI’s in-package hall-effect current sensor can provide high accuracy combined with low drift, enabling accurate current measurements over both lifetime and temperature. Additionally, the in-package design also provides a compact design without sacrificing isolation performance, without adding system complexity or cost. In recent years, there has been a trend in solar inverter system to use in-package hall-effect current sensor to replace the traditional thorough-hole one, that benefits solar system performance, power efficiency, and reliability.