HW issues of current sensing by DC-link shunt resistor

摘要

This paper deals with issues and challenges of current sensing using DC-link shunt resistor in three-phase power inverter motor control applications. Main parameters of shunt resistors relevant to the DC-link current sensing are discussed. Main factors influencing the accuracy are described, including the shape of the footprint and soldering. An example of a sensing circuit is introduced, discussing the key parameters and challenges needed to be dealt with in terms of the accuracy of the measurement and mainly the proper operation of the sensing circuit in the whole range of operation.