Analytical Solution to Voltage Balance Control in a 3-Level Neutral-Point-Clamped Inverter

This paper considers an analytical solution to voltage balance control in three-level neutral-point-clamped inverters. The three-level inverters become more popular in industrial applications, renewable energy and precise control solutions. The problem of voltage balancing is solved by means of various strategies such as additional common-mode voltage controller or predictive control strategies. In this paper the analytical solution to this problem is given. The processes, which cause the unbalance, are considered and voltage correction equations are derived. The operation of the algorithm was verified using modeling experiment that proves feasibility of the method.