Optimal PWM microprocessor-controlled current-source inverter drives

Novel On-Line Microprocessor Generation of Harmonic Elimination and Minimisation PWM Control Strategies using Regular-Sampling Techniques

“…As illustrated in Fig 14 the effects of optimising each strategy at slip frequencies of 0, 0.2, 0.4 and 0.8 etc is shown, suggesting that minimal position error can be achieved over the complete load range by implementing only two optimal strategies, in this case. These results confirm the superior performance of the optimal PWM CSI drive, compared with the conventional QSW CSI (120°) and QSW DCSI drives, which results from the more flexible optimal PWM strategy [23).…”

“…These fast modelling techniques have been used as a basis for developing very simple closed-form analytic expressions for ~w,(t) and ~PE (t), which when included into the minimisation procedure provide extremely efficient optimal PWM solutions [22). Experimental and CAD results demonstrating the application of these optimal ,,,.-( PWM strategies have been presented in some detail previously for the conventional CSI drive [22,23] (120° conduction), the series connected CSI (SCCSI) drive [24] (180° conduction) consisting of three single-phase bridges in series, and the duplex CSl drive [19,21] consisting of two 120° CSI's in parallel.…”

Model Predictive Controller-based, Single Phase Pulse Width Modulation (PWM) Inverter for UPS Systems

“…Microcomputer-based techniques using preprogrammed PWM patterns have also been utilized. In these techniques, the PWM patterns are generated by computing switching edges that satisfy certain performance criteria such as controlling the fundamental component and eliminating specified harmonics [8]. These techniques have drawbacks of slow voltage regulation response and phase displacement with load varies.…”

Solving the optimal PWM problem for single-phase inverters

“…As the odd-indexed Chebyshev polynomials are odd polynomials, we can write With this notation, the PWM equations become or (6) where are the sums of powers of . Equation (6) forms a set of linear equations for , .…”

“…Once the values are obtained by solving the linear system (6), one has the following problem. Given , find the solution to the following system of nonlinear equations (7) .…”