This study presents a practical method to find a high-frequency model of AC machine in order to predict leakage current and shaft voltage A voltage-source inverter with hard switches generates pulse width modulated voltage with high dv/dt and common-mode voltage, which causes leakage current and shaft voltage due to stray capacitances in an electric motor At fundamental frequency (a few hundred hertz), an equivalent circuit of an electric motor consists of inductances and resistances without considering stray capacitances This study presents a practical approach in extracting high-frequency parameters of an electric motor for leakage current and shaft voltage analysis Input impedance (magnitude and phase values) of several configurations of an AC motor is measured using a network analyser All capacitive couplings between windings, stator and rotor are extracted based on theoretical analysis and measurement results Simulations are compared with test results to verify the proposed method and model

Practical approach to model electric motors for electromagnetic interference and shaft voltage analysis

With indispensable and rapid ingress of renewable energy sources in power systems, the communication between the distributed energy sources has become very crucial to have a reliable distribution management system (DMS). In this paper, wireless access support is proposed for Distribution Management System (DMS) and microgrid control center (MGCC) using WiMAX protocol. MATLAB/Simulink was used to model the WiMAX physical layer. The bit error rate (BER) v/s signal-to-noise ratio (SNR) curves were plotted and promising results were obtained.

Wireless Access Support for Distribution Management System (DMS) to Microgrid Communication in Power Network

The transformation from conventional power grid to smart grid has brought interdisciplinary concepts together. The distribution management system is a part of the smart grid and is a complex entity which requires different applications for monitoring, control and manage the distribution network operator (DNO). In this paper the communication framework is proposed for microgrid control center (MGCC) to DMS using long term evolution protocol (LTE). The LTE physical layer is modeled in MATLAB/SIMULINK and the bit error rate (BER) to signal to noise ratio (SNR) curves are plotted.

A Framework for Microgrid to Distribution Management System (DMS) Communication in Smart Distribution Network

The stray capacitances existing between the windings and the frame of the electric machines are the main coupling route of common-mode (CM) electromagnetic interferences (EMI). In this study, the magnitude of parasitic capacitances present in permanent magnet synchronous motor (PMSM) with fractional-slot concentrated winding (FSCW) and conventional-slot distributed winding (DW) are compared through finite element analysis (FEA) simulation. The simulation result shows that a reduced parasitic capacitance and increased CM impedance can be obtained by employing FSCW compared with DW. The Validation of the simulation result is carried out through a practical impedance measurement.

Adisu Teshale

Papers

A Framework for Microgrid to Distribution Management System (DMS) Communication in Smart Distribution Network

Analysis of Common-mode EMI in PM Synchronous Machines with Fractional-slot Concentrated Winding