A digital control algorithm for a current-mode (CM) and a voltage-mode (VM) synchronous buck converter (SBC) is developed. In both cases, the design leads to a stable controller, even for a duty cycle larger than 50%. The desired output voltage and the transient response can be independently specified. Moreover, zero steady-state error in the output voltage can be obtained with the aid of addit...

This paper presents a novel design of Proportional and Integral (PI) like Fuzzy Logic Controller (FLC) for Buck converters that integrates linear control techniques with Fuzzy Logic .The design procedure allows the small signal model of the converter and linear control design techniques to be used in the initial stages of FLC design. This simplifies the small signal design and stability assessm...

In this paper an efficient high step-up converter with a coupled- inductor with soft- switching operation is presented. The proposed topology includes a coupled-inductor boost converter for raising the voltage gain. Moreover, a simple auxiliary resonant circuit composed of an auxiliary switch, a clamping diode and a resonant tank (inductor, capacitor), is adopted in this paper. The coupled-indu...

A systematic and unified method using the signal flow graph (SFG) technique is presented in analyzing dc–dc pulsewidth modulated (PWM) switch mode power converters (SMPC’s) operating in the continuous conduction mode (CCM). Loop gains for single and multiloop systems are reviewed. The SFG of the converter is then generated from the perturbed state-space averaged (SSA) equations, and the charact...

This paper deals with the problem of controlling energy generation systems including fuel cells (FCs) and interleaved boost power converters. The proposed nonlinear adaptive controller is designed using sliding mode control (SMC) technique based on the system nonlinear model. The latter accounts for the boost converter large-signal dynamics as well as for the fuel-cell nonlinear characteristics...

This paper investigates the operation of a currentcontrolled Voltage Source Converter (VSC) under weakgrid conditions caused by large grid impedance. Threedifferent current controller structures are investigated; theconventional decoupled PI-controller in the synchronouslyrotating reference frame, Proportional Resonant (PR)controllers in the stationary reference frame, a...

This paper proposes an approach for designing a R-2R 10 bit Digital to Analog Converter (DAC) which could be made to operate at low voltage supply by efficiently exploiting the cascaded Operational Amplifier (Op-Amp) architecture. The DAC operates at a 3V power supply with a settling time of 50-100ns , dynamic range of around 50-60 dB for signals upto a frequency of 10Mhz. Graph & simulation re...

Experience and theoretical analysis show that the voltage and power stability becomes an important issue when high-voltage direct current (HVDC) systems using line-commutated converters (LCC) are connected to AC systems with low short-circuit capacity and that these problems become more pronounced the lower the short-circuit capacity of the connected AC system is, as compared with the rating of...

The switching magnet for beam distribution is served with Digital Signal Processor (DSP) controlled PWM switching-mode power supply (SMPS). This SMPS is employed phase-shifted parallel (PSP) operation of IGBTs. This technique allows ± 350 A, 2.5 Hz stair output, and ± 350 A at bipolar mode operation. Current feedback and input voltage feed-forward control schemes are applied to improve the outp...

In this paper, the dynamics of a DC-DC boost power converter under variable structure control is studied applying bifurcation analysis techniques. The switching hyperplane coefficients are considered as bifurcation parameters. The dynamic phenomena detected in this work suggest new types of sliding bifurcations. This analysis is relevant in the context of sliding mode control with auxiliary ada...