Power Electronics and Energy Storages for Automotive Industry and Renewable Energy Networks

1. Introduction

The global efforts to decarbonize energy systems and mitigate climate change have led to unprecedented levels of attention being paid to the transportation and electricity sectors. Together, these sectors account for a substantial share of worldwide CO₂ emissions, driven by the persistent reliance on fossil fuels for mobility and grid stabilization. In response, international agreements, including the Paris Agreement (COP 21) and subsequent COP summits [1], have set ambitious targets for emission reductions, pushing for a rapid transition toward electrification, renewable energy integration, and energy efficiency. The Intergovernmental Panel on Climate Change (IPCC) has repeatedly warned that limiting global warming to +1.5 °C by 2050 requires transformative changes across energy generation, storage, and end-use systems [2]. Within this context, the European Union’s “Fit for 55” package and the broader Green Deal have further accelerated the shift, mandating steep cuts in vehicle emissions and a dramatic increase in the share of renewables in the energy mix [3]. However, the intermittent nature of renewable sources [4,5,6], such as solar, wind, and hydro, combined with the dynamic load demands in power-demanding areas like electric mobility [7,8] and pumping technologies [9,10,11], introduces critical challenges in power conversion, grid stability, and energy management [12,13].

Power electronics serve as the enabling technology of this integration, providing the essential interface for efficient energy conversion that includes new types of semiconductor switches, bidirectional power flow, and real-time control [14,15,16]. Meanwhile, advanced energy storage technologies, such as lithium-ion batteries, solid-state systems, hydrogen-based storage, and supercapacitors, must have higher density, a longer life, and enhanced safety to meet automotive and grid-scale demands [17,18,19]. The combination of power electronics and energy storage thus holds the key to unlocking flexible, resilient, and low-carbon ecosystems. Recognizing this, researchers worldwide have explored innovative converter topologies, battery management systems, thermal management strategies, and vehicle-to-grid (V2G) architectures [20,21].

This Special Issue compiles seven contributions that address these challenges across converter topologies, energy storage systems, thermal management, intelligent gate drivers, and renewable energy network control. This collection includes original research on modular converters, flywheel and phase-change storage solutions, model-free control strategies, low-cost IGBT driving algorithms, and optimal energy management for microgrids, alongside a review of renewable energy–desalination synergies. Together, these works advance the efficiency, reliability, and scalability of technologies at the heart of automotive and renewable energy networks. The following articles collectively underscore that power electronics and energy storage are not merely enabling technologies but rather the cornerstones of a decarbonized future.

2. An Overview of Published Articles

Recent advancements in the field of power electronics and energy storage have focused on enhancing conversion efficiency, system robustness, storage density, and intelligent control through innovative topologies, modular architectures, advanced materials, and model-free algorithms. One notable approach addresses power quality challenges in cold ironing (CI) systems, where a stable and clean power supply is essential for moored vessels. A robust model-free control strategy for modular multilevel converter (MMC) inverters was proposed, demonstrating compliance with IEC/ISO/IEEE 80005-1 standards [22]. This approach is shown in the first paper (contribution 1) and it effectively mitigates power disturbances without relying on an accurate system model, offering enhanced resilience and simplified implementation in demanding port environments.

Additionally, the need for high-voltage conversion ratios in automotive and renewable applications has driven the development of a high-conversion-ratio multiphase nonisolated converter built from generic modular LC cells. This unique architecture, hinging on a generic capacitor–inductor switching module, enables exceptional modularity and design scalability. The authors of the second paper (contribution 2) show that the converter can provide a quick extension pathway for designers, allowing for adaptation to diverse voltage and power requirements while maintaining high efficiency and reduced component stress.

In the domain of kinetic energy storage, a high-speed flywheel energy storage system (FESS) with a hybrid multi-layered rotor structure was developed and analyzed using ANSYS (2019 R3 v19.5). With advances in composite materials enabling ever-higher rotational speeds, the authors of the third paper (contribution 3) systematically investigated rotor stress distribution and structural integrity. Their findings contribute to improving the power density and cycle life of FESSs, positioning them as viable alternatives to grid stabilization and automotive recuperation systems.

Thermal management remains a critical bottleneck for photovoltaic (PV) cell efficiency, which degrades with rising temperature. A study on shape-stabilized phase-change materials (PCMs) with expanded graphite was conducted by the authors of the fourth paper (contribution 4). They also investigated the application of PCMs for passive PV cooling. By selecting appropriate organic PCMs and preparing composite panels, the authors demonstrated enhanced thermal regulation, improved electrical output, and structural stability over repeated thermal cycles. This approach offers a passive, maintenance-free solution for extending PV lifetime and performance.

Optimal energy management and voltage stabilization in renewable networks were addressed through a Lyapunov stability-based framework for microgrids integrating multiple energy sources. In the fifth paper (contribution 5), the authors propose a control strategy derived from a stability analysis of a simple boost converter, ensuring robust voltage regulation and efficient power-sharing among distributed generators. This work provides a theoretically sound yet practically implementable solution for urban building microgrids where renewable penetration is rapidly increasing.

Semiconductor devices are the workhorses of power conversion, and intelligent gate driving is essential for reliable IGBT operation in traction drives and renewable converters. The authors of the sixth paper (contribution 6) detailed the development and low-cost microcontroller implementation of intelligent gate-driving algorithms, including features such as active short-circuit protection, dv/dt control, and fault diagnostics. By demonstrating that advanced driving functions can be realized on affordable hardware, this work lowers the barrier to deploying intelligent drivers in cost-sensitive automotive and energy applications.

Finally, a comprehensive review provided in the seventh paper (contribution 7) examined the synergy between renewable energy and desalination, an increasingly critical nexus as water scarcity intensifies under climate change. This review provides an overview of current practices, including reverse osmosis powered by solar and wind, and outlines future directions where power electronics and energy storage play enabling roles. Topics such as variable-speed drives, energy recovery devices, and battery-integrated desalination plants are discussed, highlighting the potential for water–energy co-management in coastal and off-grid communities.

3. Conclusions

By exploring innovative converter topologies, advanced storage technologies, intelligent control strategies, and modular architectures, these research efforts contribute to the development of more efficient, resilient, and sustainable power electronics and energy storage systems for automotive and renewable energy applications. The solutions considered include robust model-free control for MMC inverters, high-conversion-ratio modular multiphase converters, high-speed flywheel energy storage systems, and shape-stabilized phase change materials for PV thermal management. Additional innovations, such as Lyapunov-based energy management frameworks, low-cost intelligent IGBT gate drivers, and renewable energy–desalination synergies, further enhance the reliability, affordability, and scalability of these systems. Overall, these advancements aim to facilitate the creation of eco-friendly, high-performance power conversion and storage solutions capable of supporting the global transition toward decarbonized transportation and renewable energy networks.