This paper proposes a current sensing method to eliminate the immeasurable areas in three-phase inverters using the shunt resistors. Conventional shunt resistor-based current sensing methods have immeasurable areas in the voltage vector plane. Since motor control performance is degraded by the immeasurable area, various current reconstruction techniques have been proposed to expand the measurement range. Nevertheless, the software algorithm is quite complex, and the reconstruction ability is still unsatisfactory. In the proposed method, shunt resistors are located in series with the inverter output lines to obtain the motor phase currents. Both ends of the shunt resistors are at the high-potential as the dc-link voltage. High-potential voltages are lowered to the common-mode voltage level of the analog amplifier using voltage divider, and voltage drops across shunt resistors are detected by instrumentation amplifiers. Immeasurable areas are completely eliminated because phase currents can be detected directly through line shunt resistors. Simulations and experiments are carried out to verify the effectiveness of the proposed current sensing method.

中文翻译：

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利用三分流电阻消除电压矢量平面不可测区域的相电流检测方法

本文提出了一种电流检测方法，以消除使用分流电阻器的三相逆变器中的不可测量区域。传统的基于分流电阻的电流感测方法在电压矢量平面中具有不可测量的区域。由于不可测量区域会降低电机控制性能，因此已经提出了各种当前的重建技术来扩展测量范围。尽管如此，该软件算法相当复杂，重建能力仍然不尽如人意。在所提出的方法中，分流电阻器与逆变器输出线串联，以获得电机相电流。分流电阻的两端都处于高电位作为直流母线电压。使用分压器将高电位电压降低到模拟放大器的共模电压电平，分流电阻上的压降由仪表放大器检测。由于可以通过线路分流电阻器直接检测相电流，因此完全消除了不可测量的区域。进行仿真和实验以验证所提出的电流感测方法的有效性。