� A 15-level Modified Packed U-cell (MPUC) Inverter is investigated in this study, and a Selective Harmonic Mitigation (SHM) method is used to reduce and eliminate several harmonic components on the output voltage, resulting in a lower Total Harmonic Distortion (THD) factor. The proposed MPUC-15 inverter can provide a 15-level output with only eight switches, making it the most compact inverter to date. In order to achieve the 15-level output, the inverter's dc link voltage is kept in the ratio of 1/4:3/4:1. A detailed explanation of the PMUC15 inverter's operation with various switching states is provided. The MPUC15 inverter allows for the elimination of more harmonics. However, the equation of the harmonic becomes more complex as additional switching angles emerge in the harmonic equations, which are difficult to solve using typical linear optimization methods. The SHE-PWM equations for a 15-level inverter are created and solved using Deferential Evaluation (DE) with a variable modulation index, a current optimization method. The reported output THD has been less than 5, and angles for various modulation indexes have been compiled and provided in tabular format. The inverter prototype is built in MATLAB®/Simulink, with a Typhoon HIL SCADA setup for testing the results of the DE algorithm. © 2022 Praise Worthy Prize S.r.l. All rights reserved.