# Emerging Technologies for Advanced Power Electronics and Machine Design in Electric Drives
## 1 Introduction  
In recent decades, there has been a notable evolution in electric drives, driven by advances in power electronics and supported by increased computational power. The development has been remarkably rapid in recent years, which have been characterized by the green revolution in the transportation and energy sectors. Both industries are compelled to optimize the use of available energy to achieve the highest efficiency of power converters. Consequently, the progress in power converters is closely linked to advancements in semiconductor technologies [1]. The demanding criteria set by these emerging technologies [2; 3; 4] make it necessary to consider various other factors during the design process, including the development of passive components, printed circuit board (PCB) materials, packaging, and more. Their joint impacts are often overlooked in many existing review papers.  
Advances in power electronics and electric machines have been addressed by several researchers during the last decades. [PERSON] et al. focused explicitly on this topic and published a general overview of current and future trends in two papers in 1993 [5] and 2008 [6], followed by a comprehensive book in 2020 [7]. [PERSON] and [PERSON] also published a handbook on power electronics and motor drives in 2018, focusing on industrial electronicssolutions [8]. [PERSON] et al. published a book on power electronics and drives for the electric powertrain [9]. A similar overview was also provided by [PERSON] et al., focusing on the development of power electronics for industrial and traction machine drives [10]. [PERSON] et al. described the current state of the art and future challenges of industrial electronics in the field of electric transportation, mainly aiming at the critical drivetrain components [11]. [PERSON], [PERSON], and [PERSON] published a series of papers on multiphase drives, focusing on general recent trends, design, and control [12; 13; 14; 15]. Similarly, [PERSON] et al. published a review paper on multiphase drives, focusing on automotive traction applications [16].  
Although the aforementioned reviews provide a comprehensive overview of the state of the art in the field of power electronics and drives, they mostly concentrate on individual subfields (electronics, machines, design, optimization, control, etc.) and less on offering a broader inter-connected aspect of the topic. The literature reveals a need for a paper that would fill this gap by providing the readers with a general overview of the field of power electronics for electric drives, accompanied by a review of the individual subfields, with each part providing an insight into past and recent developments, as well as future trends, supported by relevant references.  
In order to remedy this shortcoming, this paper discusses the tendencies in research and development of power converters for electric motor drives in more detail. The focus is on new topologies of electric drives (multilevel and multiphase), new technologies of power switches (wide bandgap), and the latest simulation-based and multi-objective optimization-based methods in electric drives design.  
This paper is organized as follows. Section 2 discusses electric drive topologies, detailing series, parallel, and multiphase configurations, and innovative designs such as open-end winding, dual stator, and intelligent stator cage drives. Section 3 highlights semiconductor technologies, focusing on the shift from silicon to wide bandgap semiconductors, such as silicon carbide and gallium nitride for enhanced electric drive performance. In Section 4, trends in integrating power electronics and electric machines are discussed, emphasizing compact and efficient drive designs. Section 5 covers design tools, noting the importance of multidomain co-simulations, multi-objective optimization (MOO), and in-the-loop testing for optimizing electric drives.