Electrical Drives with Integrated Output Filters Part I - Converter Topologies, Filter Structures and Design, Modulation and System Integration

Electric motors consume over half of global electricity, yet most installations still operate as Direct-On-Line systems without variable-speed control. Broader adoption of Variable Speed Drives (VSDs) has been limited by the installation complexity and the additional components required by PWM inverters, including shielded cables, inverter-duty motors, and external dv/dt and EMI filters. Recent advances in wide-bandgap (WBG) semiconductors enable high-frequency operation and compact power converters, but fast voltage transitions intensify dv/dt stress, common-mode excitation, cable-reflection overvoltages, electromagnetic interference (EMI), and related reliability concerns. Drives with integrated output filters offer a unified drive-side solution to shape the high-frequency drive-machine interaction, enabling near-sinusoidal motor voltages, reduced losses and emissions, and the use of standard motors and unshielded cables. This facilitates large-scale retrofitting of existing installations with significant energy-saving potential. This paper (Part I of II) presents a system-level review of drives with integrated output filters, focusing on converter topologies, output-filter structures and design considerations, and modulation strategies targeting dv/dt mitigation, common-mode reduction, and efficiency improvement. Key design considerations, including losses, voltage drop, component stress, and installation characteristics, are discussed, together with industrial practice, emerging trends, and implications for condition monitoring compatibility and process-level digitalization towards reliable and cost-effective WBG-based sine-out drives. Part II complements this review by covering observer and control strategies required for resonance stabilization and active damping in sinusoidal-output LC-filtered drives.