Proposing an Efficient DC Voltage Conditioning Device for LVDC Systems

Proposing an Efficient DC Voltage Conditioning Device for LVDC Systems

Voltage quality is an important issue for low voltage DC systems (LVDC) including sensitive loads. This paper proposes a multi-purpose DC Voltage Conditioning Device (DCVC) to compensate the voltage disturbances and fluctuations in a DC microgrid. This device is a series connected element that can control the DC voltage in a standard limit at the load point and presents a high quality power supply for sensitive loads in DC microgrid. DCVC acts as a voltage conditioner by injecting required positive/negative voltage into the distorted DC voltage. This is done by a controlling command to the switches and helps fast restoring ofthe DC voltage to its normal state. A simple LVDC microgrid is simulated using PSCAD/EMTDC and the effect of DCVC is studied under different voltage disturbances; i.e. voltage sag/swell and voltage disturbances resulting from pulsating loads. Results show that the proposed DCVC with an appropriate controller is able to improve the system voltage quality during various disturbances.