Kryvoruchko D. An adjustable compensator of complete power non-active components in ship electric power systems with semiconductor converters

Dissertation is intended for further investigation of the theory of electromagnetic compatibility and electric power quality in the ship electric power systems (EPS) with powerful semiconductor converters (SC) and adjustable power line conditioners (APLC). The APLCs provide compensation of reactive power on main frequency with simultaneous decreasing high harmonics. The main feature of the mentioned EPS is a proportionality of power consumers and total power of generating aggregates. The new improved structure of hybrid APLC which consists of the uncontrolled power resonant LC-filter (RF) and the reactor compensator (RC) with pulse-width regulation (PWD) is created and theoretically proved. The hybrid APLC eliminates the need for an additional RF, increase the performance of APLC, excludes the generation of low frequency harmonics into the EPS, excludes the resonant increasing of harmonics in the EPS. An analytical condition for adjusting of the frequency characteristics of the equivalent resistance of the EPS with APLC and SC with the spectra of harmonics generated by SC and RC that eliminates the possibility of resonance of higher harmonics of currents is obtained. To calculate the non-sinusoidality factor of the voltage, on the basis of the analysis of EPS with APLC and SC, using the operator method of individual components, harmonic analysis and Parseval’s equality, analytical expression in final form is obtained. The expression takes into account the entire harmonic spectrum and the mutual impact of the system elements on electromagnetic processes and provides a slight discrepancy in calculations with real results. The conditions of full RP compensation are determined, the structural-functional scheme of the automatic control system (ACS) of APLC in AEPS with SC is offered and implemented. The ACS contains sensors of generator voltages and currents, standard calculation unit and low-pass filter for RP determination, regulator and PWD. To adjust the ACS regulator parameters, an optimization model was created. The model used the Simulink Design Optimization library with the Check Step Response Characteristics block and setting quality criteria for transients, in particular, the requirement to reduce the duration of transients to 0.15 s. Keywords: electromagnetic compatibility, electric power quality, complete power non-active components, adjustable power line conditioner, passive filter, active filter, total harmonics distortion factor, reactive power, active-power, distortion of voltage.