Efficient Zero-Value-Cross Detection for Single-Phase Mains-Powered Motors: A Comparative Study

This paper proposes solutions for zero-value-cross detection (ZVCD) in a single-phase mains-powered motor used for high-torque tightening. Four different applications are presented: resistor-polarized digital input, a resistor-polarized optocoupler, comparators steering up the optocoupler, and n-MOSFETs polarizing the optocoupler. The performance of each solution is evaluated in terms of complexity, dimensions, power dissipation, and response time. The n-MOSFET-based solution is found to be the most suitable, providing a simple design, low power dissipation, and almost instantaneous response. This solution meets the project's requirements for accurate and fast zero-crossing detection.