Electric drives applications have been worldwide adopted for the transportation electrification. An electric drive system is constituted by two main components: the power electronics converter and the electrical machine. Traditionally the design workflow consisted in the separate realization of these two parts, by different teams or even organizations. This requires strong assumptions regarding operating conditions and may lead to actual performance at system level far from the one expected. In this article, a unified design methodology of the two subsystems is presented considering the true operating conditions, allowing a more accurate assessment of power losses at system level and identifying the influence of the converter design choices on the electric machine performance. As a case study, this article presents a comparative analysis among three different converter topologies designed to drive a 8.5 kW-120 krpm surface PMSM. The study aims at comparing the considered systems in terms of overall efficiency, losses distribution and system complexity. At first converters are simulated in Matlab-Simulink to estimate the losses and the current waveforms, that are then used in the Finite Element model of the electrical machine to estimate the loss components in a real scenario. The models developed are then validated by means of experimental measurements. This article highlights the new understanding that can be gained by considering the interactions between subsystems , allowing a more conscious choice of the converter topology to achieve optimal overall performance.

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The exponential growth experienced by the semiconductor manufacturing field has led to a large proliferation of devices with large amounts computational power, enabling countless technologies and revolutionizing many fields. Control systems and machine drives are certainly among them. Much research is being carried out to develop multi-phase and fully segmented machines, with their inherent fault tolerance. To take full advantage of the redundancy and load sharing capabilities of the machine structure, with multiple winding sets, a suitable distributed control method must be used. A high performance network between the drives is thus required. This paper will present an overview of the available communication protocols that are used in the field and evaluate how suitable are they to this new class of very demanding real time tasks.

In modular distributed architectures, the adoption of a communication method that is at the same time robust and has a low and predictable latency is of utmost importance in order to support the required system dynamics. The aim of this paper is to evaluate the consequences of the random jitter on machine drives distributed control, caused by the messages’ re-transmission in case of an error in the received data. To achieve this goal, two different Forward Error Correction (FEC) techniques are introduced in the chosen protocol, so that the recipient of the message can correct random errors without the need of any additional round trip delays needed to request and obtain a re-transmission. Experimentally validated simulations are used to evaluate the impact of random network derived jitter on a real world closed loop control system for distributed power electronic converters.

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