Abstract : This article introduces the application of Yaskawa's new inverter in the sintering machine drive system. Keywords : Inverter, Harmonic, Sintering machine 1. System Overview Before Modification The second-phase sintering machine of a certain factory used an early VVVF inverter. Since its commissioning, the sintering machine drive unit has been unstable, and the inverter's control performance has not met design specifications . Initially, the foreign supplier provided the Chinese side with a set of spare parts. Due to the use of analog control, the regulator experienced drift and aging, resulting in poor control performance, high inverter output harmonics, and decreased efficiency of the inverter and motor. Furthermore, due to the harsh on-site environment, with the aging of the equipment, mechanical wear and deformation, and increased motor load, the inverter used for the sintering machine drive frequently tripped due to overcurrent after each scheduled maintenance, causing motor temperature rise, noise, and vibration. 1.1 System Testing The system temperature and motor voltage and current were tested. Temperature test results are shown in Table 1, and motor three-phase current and voltage are shown in Tables 2 and 3. The highest motor temperature reached 95.1℃, with a maximum temperature rise of 55.9℃. Although the motor's insulation class is B, the nameplate specifies an allowable temperature rise of 70℃. However, given the excessively high temperature rise, an external 380V, 3.7kW fan was connected for forced cooling of the sintering motor. 1.2 System Analysis [b][align=center]For details, please click: Application of Yaskawa Inverters in Sintering Machine System Retrofit[/align][/b]