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Digital control technique is becoming an attractive alternative for high-frequency switching mode power supply (SMPS). This paper introduces a fully synthesizable digital sliding-mode (SM) controller for high-frequency dc/dc SMPS. The proposed SM controller is associated with a digital pulsewidth modulation (DPWM) block to operate at constant and high switching frequency compared to already published approaches. The digital SM controller is experimentally validated by means of field-programmable gate array in a 4-MHz step-down converter with 10-bit analog-to-digital conversion (ADC) and 11-bit DPWM. Measured dynamic performances are superior to conventional digital controllers for dc/dc SMPS. [ABSTRACT FROM AUTHOR]

This paper presents a comparative study of three predictive current control schemes for permanent-magnet synchronous machine (PMSM) drives. The first control scheme predicts the future evolution of the currents for each possible configuration of the inverter legs. Then, the switching state which minimizes a given cost function is selected and applied during the next sampling time. The second control scheme uses a modulator to apply two configurations of the inverter legs during a computation period. Among these configurations, one leads to null voltages. The duration of the other configuration is calculated in order to minimize the distance between the obtained state vector and the desired one. The third control scheme uses a model of the PMSM in order to predict the stator voltages which allows us to reach the desired currents after one modulation period. An algebraic method is presented to compute the duty cycle of each leg of the inverter in a direct manner. These control schemes are detailed and tested using the same switching frequency on the same test bench (1.6-kW PMSM drive). A simulation study is performed in order to compare sensitivity to parameters of each control scheme. Experiments confirm the simulation results. [ABSTRACT FROM AUTHOR]

This paper presents a control scheme suitable for systems composed of a continuous process modulated in energy by a power converter with a finite number of topologies. To track the continuous reference values, a topology of the power converter is determined from a criterion based on a process state variable model and taking into account the possible topologies of the power converter. The proposed hybrid control scheme is applied to an electrical motor drive composed of an inverter coupled to a permanent magnet synchronous machine. An evolution which insures a fixed modulation frequency is also proposed. Experimental results validate the feasibility and effectiveness of the proposed schemes. [ABSTRACT FROM AUTHOR]