A Remote Voltage Supply Method Based on Sinusoidal-Excitation Cable Impedance Detection

Due to the inherent impedance of cables, a voltage drop will occur when a power source feeds a remote load through long-distance cables. Therefore, it is necessary for the power supply equipment to introduce cable impedance self-detection capability and perform cable voltage drop compensation. This paper proposes a cable impedance detection method based on sinusoidal excitation, which can achieve single-port impedance detection of cable. Based on the detected impedance values, cable voltage drop compensation can be further achieved by adding current and current-change-rate sampling. Besides, adopting feedback and disturbance feedforward composite control method in closed loop helps to overcome the delay response problem caused by cable self-inductance, which improves the fast response ability of power source and can effectively respond to the dynamic changes of load. Finally, an experimental prototype is built, and the experimental results fully demonstrate the theoretical analysis and the performance of the proposed method.