Over the years, high voltage transmission of large energy blocks over long distances has widely developed from the Line Commutated Converter (LCC) technology. However, the continuous expansion of the AC network and the increase in renewable energy penetration leads to the weakening of Electric Power Systems (EPS), causing operational problems for the LCC-HVDC. This paper evaluates the degree of contribution of the VSC-HVDC on the LCC-HVDC dynamic performance when the infeed is in a hybrid multi-infeed HVDC system. Through a steady-state mathematical framework, the new concept of Hybrid Power Voltage Interaction Factor ($\mathit{h}$PVIF) is proposed to assess the transient stability improvement of LCC. Additionally, this article introduces two key contributions from $\mathit{h}$PVIF: the complementary Improved Commutation Failure Immunity Index ($\mathit{i}$CFII), as a measure of the effective short circuit enhancement, as well as the apparent line length, which emulates the line lengths adjusting the power dispatch in the VSC-HVDC. PSCAD/EMTDC^TM time-domain dynamic simulations are performed to assess the indexes, and the Matlab${}^{\circledR }$ software will be used to assist in mathematical operations.

A doubly three-phase fed synchronous reluctance machine (SynRM) using a full integrated H-bridge power converter topology for each phase is designed for electrical vehicle (EV) powertrain applications. The proposed motor and EV powertrain design consists of redundant motor and power converter, improving security and safety of the overall system. The main objective of this SynRM is to be able to provide instantaneous power and high power density, high torque at low speeds and high power at high speeds, wide speed range, high efficiency over its entire operating range, high efficiency regenerative braking, robustness reliability, high safety and security system at reasonable cost. Under these requirements a 60 kW, 9000 r.p.m. and 400 N.m. SynRM prototype has been designed. The SynRM powertrain thermal design is verified using finite difference method and by Solidworks flow simulation software. A prototype has been built to verify the motor design and the high efficiency of the SynRM based EV.

A doubly three‐phase fed synchronous reluctance machine (SynRM) is designed for electrical vehicle powertrain application. SynRM aims to deliver instant power and high power density, high torque at low speeds and high power at high speeds, wide speed range, high efficiency throughout its range of operation, ruggedness, high safety at a reasonable cost. Under these requirements, a 60 kW, 9000 rpm and 400 Nm SynRM has been designed. The main objective is to demonstrate the SynRM powertrain operation behaviour and determinate the operation points electrically and thermally. To reach the proposed SynRM goal, a new direct torque control algorithm based on output regulation subspace theory control is presented. The winding motor topology is galvanic isolated, so it is possible to operate with the six phases directly to the load and because of that, the combination with a back‐to‐back (B2B) converter becomes so profitable. To validate the system, two B2B full‐converters and two motors (SynRM and induction machine) were used in a real test bench. Finally, a simulated and real efficiency map is obtained covering different drive cycles range. Some remarks about normal and failure mode of operation are presented.

This study introduces a method for controlling a system that rectifies electric current where power is transferred from several offshore wind power generation systems through a common offshore AC line, into a diode‐based bridge. This modular rectifier comprises one or more uncontrolled modules (such as diode rectifiers). According to the study, the wind power supply systems receive a reactive power reference from a central external regulator to maintain the common AC‐line frequency. Although there are other control methods for this topology, the proposed external control uses commercial wind turbine with no changes in their internal control. The power plant control systems use their own algorithm to select the active and reactive power reference, maintaining the original wind turbine control unaltered. This method for controlling the voltage and the frequency of local offshore grid allows the operation of the different rectifiers end of the HVDC link. PSCAD ^® simulations are used to prove the technical control and the design concept.

This work proposes a metric to assess the spread of the switching frequency profile of power converters, focusing on Finite Control Set-Model-Predictive-Control (FCS-MPC)-based converters, and analyses the effect of the filter sizing, sampling period, and cost function on the switching frequency spread. An algorithm that estimates the instantaneous switching frequency is the basis of the proposed metric. The literature review shows that only two metrics, THD and average switching frequency, are used to assess the switching frequency of FCS-MPC, but the findings of this research show that both are insufficient to characterize FCS-MPC. The main contribution of this paper is that now researchers can quantitatively assess the switching frequency spread of FCS-MPC through the proposed metric.

A six‐phase synchronous reluctance machine (SynRM) is designed for electrical vehicle (EV) powertrain applications. The SynRM in the charger mode is able to provide instantaneous power and high power density, high efficiency with two modes of charge, robust reliability, high safety and fault tolerance. The properties of the SynRM are 60 kW, 9000 rpm and 400 N m. The main objective of the SynRM powertrain used as a charger is proved electrically, thermically and to be fault tolerant using a specific test bench. The winding motor topology is galvanic isolated, making it possible to load directly from the single‐phase and three‐phase grid, enabling two ways of charging, which increases the reliability. For this reason, the back‐to‐back full‐converter and the SynRM as a charger are used. The main goal is to prove the utility as a charger and the great efficiency derived from the SynRM plus inverter topology for electric cars. This SynRM + inverter topology offers redundancy for all load modes.