Owing to more and more sensitive loads installed in modern ships, ship owners and builders have been faced with rising numbers of complaints about the quality of power. However, the existing power monitoring facilities installed onboard for recording deviations of power parameters is only over steady-state conditions due to limited capacity of measurement equipment and ignores short-duration phenomena. To understand the true supply quality in ships, a power quality (PQ) monitoring technique is employed in this paper. The PQ parameters including short-duration and long-duration voltage and frequency variations in a practical commercial vessel power system under different operating conditions are analyzed and their statistic data are reported. Through PQ measurement and analysis, the quality of supply can be quantified and assessed according to classification society standards. Analysis model developed in this paper can assist them in understanding true supply quality in ships for further determining proper PQ mitigation options.
Power Quality of Supply Characterization in the Portuguese Electricity Transmission Grid