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This paper presents a novel control technique for a wide output voltage range digitally controlled SIDO boost converter. It employs minimum phase conditions reported in refid="ref1"/ , refid="ref2"/ and extends the same to SIDO boost converter to eliminate the effect of RHP zero. Further, the proposed work employs input-output linearization technique refid="ref3"/, refid="ref4"/ to linearize the control-to-output transfer function across different operating points to achieve improved stability under unbalanced loads and a wide output voltage range on each output of the proposed SIDO boost power converter. The SIDO boost regulator was verified experimentally for an input voltage of 3.3 V and a maximum simultaneous load current of 350 mA on each output. Measurement results demonstrate that the proposed design achieves a wide output voltage range of 4.8 V–13.75 V, with ability to dynamically transition across these different output voltages in both small and big voltage steps. [ABSTRACT FROM AUTHOR]

In this paper the stability and sensitivity function of three basic dc-dc converter with the consideration of circuit parasitics has been analyzed for analog and digital controller implementation. The steady state and small-signal analysis has been used to derive the mathematical expressions for uniformly sampled voltage-mode controlled converters. The effect of digital controller using the ratio of sampling to carrier frequency has been analyzed. The sampling frequency limits the voltage gain in the stepped manner and also affects the stability of the digitally controlled converter. The sensitivity function has been defined for voltage gain with respect to various system parameters. The maximum affected regions on duty ratio scale with corresponding parasitic variable have been discussed. The detailed stability analysis has been carried out for digitally implemented three basic dc-dc converters, i.e., buck, boost, and buck-boost circuits. The analytical results are verified with the simulations performed in PSCAD/EMTDC. An FPGA controller is considered as digital controller for the dc-dc converter and verification of the results through experiment. [ABSTRACT FROM PUBLISHER]

While a host of analysis techniques exist to perform steady-state analysis of open-loop converter systems, solutions for close-loop converter systems are distinctly more challenging to obtain. Analysis is done either via computationally intensive time-domain simulation or through reliance on a disconnected collection of published iteration techniques. Moreover, most of these iteration techniques deal with a system containing only one or two converters. This is not adequate to deal with a smart grid or microgrid system, which consists of multiple (more than two) converters. This paper proposes a generalized and systematic solution procedure to obtain the steady state of a system containing multiple closed-loop power converters, in a computationally efficient manner. The solution procedure consists of a general five step approach that can easily be applied to a wide variety of power converter systems. It is shown that numerous previously proposed methods may be viewed as specific implementations of the generalized systematic procedure. A new solution approach, suitable for analysis of tightly coupled multiconverter networks, is developed based on the generalized solution procedure. Results of the new approach are validated against PSCAD/EMTDC simulations for a representative multiconverter network. [ABSTRACT FROM PUBLISHER]

A new scheme of a gain/efficiency-improved serial- parallel switched-capacitor converter (SPSCC) is proposed by combining an adaptive-conversion-ratio (ACR) and pulse-width- modulation (PWM) control for step-up DC–DC conversion. For improving gain, the power part consists of one mc-stage cell and one nc-stage cell in cascade to obtain the step-up gain of (mc+1)\times(nc+1) at most. For improving efficiency, the ACR control with adapting stage number m,n is presented to select a proper gain of (m+1)\times(n+1) (m=1,2,\ldots,mc, n=1,2,\ldots,nc) according to the desired output. Further, the PWM control is adopted to enhance output regulation as well as robustness to source/loading variation. Some theoretical analysis and control design include: formulation, steady-state analysis, conversion ratio, efficiency, output ripple, stability, capacitance selection, and control design. Finally, the performance of this scheme is verified experimentally on a SPSCC prototype, and all results are illustrated to show the efficacy of this scheme. [ABSTRACT FROM PUBLISHER]