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The control and stabilization of resonant converters are essential problems in power electronics. The conventional controller design and stability analysis for these converters are based on the linearized averaged model. Nevertheless, the state variables in resonant converters have large ac variations and the validity of the linearized average model is violated. Hence, using large signal and nonaveraged models are necessary for controller design and stability analysis. In this paper, a new hybrid controller is presented that is applicable to dc-dc series resonant converters and use neither averaging nor small signal approximation. The dc-dc resonant converters are inherently switched affine... 

The subject of modeling and stability analysis of dc-dc resonant converters is still a challenge. The conventional large signal nonlinear model of the resonant converter is derived using the sinusoidal approximation and averaging followed by linearization about an operating point. Models obtained with such method involve considerable approximation, and produce results that are limited for higher performance designs. Therefore, it is essential to investigate the stability of the resonant converters using a more sophisticated model. Because of semiconductors switching, dc-dc resonant converters are intrinsically hybrid systems consist of discrete input and continuous states. The complexity of... 

The subject of modeling and stability analysis of dc-dc resonant converters is still a challenge. The conventional large signal nonlinear model of the resonant converter is derived using the sinusoidal approximation and averaging followed by linearization about an operating point. Models obtained with such method involve considerable approximation, and produce results that are limited for higher performance designs. Therefore, it is essential to investigate the stability of the resonant converters using a more sophisticated model. Because of semiconductors switching, dc-dc resonant converters are intrinsically hybrid systems consist of discrete input and continuous states. The complexity of... 

A dc-dc resonant converter has the advantage of overcoming switching losses and electromagnetic interference which are the main limitations of high frequency power converters. Nevertheless, the modeling and stability analysis of dc-dc resonant converters are considerably more complex than pulsewidth modulation counterparts. The conventional averaged linearized model of the resonant converter has limitations due to averaging and linearization. First of all, the linearized model has large modeling error in presence of large variations of reference voltage and input voltage. Furthermore, Converging area for stabilizing controllers is smaller in the averaged model. In order to overcome these... 

Single-phase power factor correction (PFC) converter circuits are non-linear systems due to the contribution of their multiplier. This non-linearity causes difficulties in analysis and design. Models that reduce the system to a linear system involve considerable approximation, and produce results that are susceptible to instability problems. In this paper a piecewise affine (PWA) system is introduced for describing the nonlinear averaged model. Then robust output feedback controllers are established in terms of the linear matrix inequality (LMI). Simulation and experiments results show the effectiveness of the proposed control method  

The most common technique for analysis and control of power electronics circuits is switch averaging. The model is not linear however, and often results in a multiplicative term in the state equations. Hence, it is common to perform a small signal linearization of the model about an operating point. Models obtained with such method involve considerable approximation, and produce results that are limited for higher performance designs. In this paper a Piecewise Affine Approximation (PWA) technique is introduced for modeling of switched circuits. Modeling of a DC-DC buck-boost converter is presented as an illustrative example to show the favorable properties and broad utility of this approach.... 

In this paper, a novel hybrid control approach is proposed to control the LLC resonant converter. Since the converter consists of both continuous variables and logical variables, it is intrinsically hybrid. Apart from that, because of fast dynamics of the converter and the fact that there is no closed form solution for discontinuous conduction modes (DCM), modeling and control of the LLC resonant converter is still a challenge. In the authors' previous work, a systematic model was proposed for the converter, the direct piecewise affine model. In this paper, an appropriate controller based on the proposed model is represented and the design procedure is discussed in details; the block diagram... 

In this paper, at first the stability condition which gives an upper stochastic bound for a class of Stochastic Hybrid Systems (SHS) with deterministic jumps is derived. Here, additive noise signals are considered that do not vanish at equilibrium points. The presented theorem gives an upper bound for the second stochastic moment or variance of the system trajectories. Then, the linear case of SHS is investigated to show the application of the theorem. For the linear case of such stochastic hybrid systems, the stability criterion is obtained in terms of Linear Matrix Inequality (LMI) and an upper bound on state covariance is obtained for them. Then utilizing the stability theorem, an output... 

In this paper, at first the stability condition which gives an upper stochastic bound for a class of Stochastic Hybrid Systems (SHS) with deterministic jumps is derived. Here, additive noise signals are considered that do not vanish at equilibrium points. The presented theorem gives an upper bound for the second stochastic moment or variance of the system trajectories. Then, the linear case of SHS is investigated to show the application of the theorem. For the linear case of such stochastic hybrid systems, the stability criterion is obtained in terms of Linear Matrix Inequality (LMI) and an upper bound on state covariance is obtained for them. Then utilizing the stability theorem, an output... 

Dynamic modeling and control of DC-DC series resonant converter (SRC) especially when operating in discontinuous conduction mode (DCM) is still a challenge in power electronics. Due to semiconductors switching, SRC is naturally represented as a switched linear system, a class of hybrid systems. Nevertheless, the hybrid nature of the SRC is commonly neglected and it is modeled as a purely continuous dynamics based on the sinusoidal approximation and averaging. However, an SRC may be purposely designed to operate in DCM so the sinusoidal approximation is no longer acceptable. Therefore, it is essential to analyze the stability using a more sophisticated model. This paper presents a novel... 

Dynamic modeling and control of DC-DC series resonant converter (SRC) especially when operating in discontinuous conduction mode (DCM) is still a challenge in power electronics. Due to semiconductors switching, SRC is naturally represented as a switched linear system, a class of hybrid systems. Nevertheless, the hybrid nature of the SRC is commonly neglected and it is modeled as a purely continuous dynamics based on the sinusoidal approximation and averaging. However, an SRC may be purposely designed to operate in DCM so the sinusoidal approximation is no longer acceptable. Therefore, it is essential to analyze the stability using a more sophisticated model. This paper presents a novel... 

DC-DC quasi-resonant converters (QRC) have the advantage of reducing switching losses and electromagnetic interference (EMI) which are the main disadvantages of high frequency power converters. The control and stabilization of these converters have always been a challenge. Traditionally, the dynamical model of the QRC is obtained using state space averaging followed by linearization about an operating point. The major flaw of this method is that state variables have large variations; thus, the linearized averaged model is not valid. Therefore, it is necessary to obtain a more precise model for the aim of stability analysis and controller design. Due to semiconductors switching, QRCs are... 

In this article, the state estimation for Automotive Slip Angle considering the measurement noise in sensor is addressed. Realtime measurement of the slip angle is applicable to many active vehicle safety applications, such as rollover prevention and yaw stability control. As the sensors that measure slip angle directly are expensive, the method to extract slip angle from other available sensors in vehicle is considered. First from the simplified nonlinear dynamic system of vehicle, a Piecewise Affine (PWA) model with calculated uncertainties is obtained. The uncertainties are the result of nonlinear system deviation from PWA model. Then using the PWA model, a Stochastic Robust Hybrid... 

In this paper, a class of uncertain piecewise affine (PWA) systems, subject to system and measurement external disturbances are studied. The uncertainties are assumed to be norm bounded and the external disturbance signals belong to the L2 space. The problem of optimizing the system response in the H?sense, by means of a piecewise affine observer-controller, is formulated as an optimization problem subject to a number of constraints in the form of matrix inequalities. The derived constraints are obtained by considering a partially piecewise quadratic Lyapunov function in combination with the general conditions for H?stability. Then the uncertain PWA approximation of the nonlinear attitude... 

Resonant converters are hard nonlinear systems which are comprised of both continuous and discontinuous nonlinearities. Many nonlinear modeling approaches lead to a very awkward, unsystematic stability analysis and controller design. Hence, stability analysis and stabilizing controller design of the popular LLC resonant converter still remain challenging as direct consequences of the absence of a "systematic modeling". In this paper, the LLC resonant converter is modeled in the form of Piece-Wise Affine (PWA) systems and a Direct Piece-Wise Affine (DPWA) model of the DC-DC LLC resonant converter is proposed. No dynamic is omitted in the modeling approach, and accordingly, the proposed... 

A problem associated with modeling and control of the power factor correction rectifiers is that the ac variations in duty cycle, as well as in the ac input voltage and current are not small, and hence the traditional small signal analysis is not justified. Nonetheless, the low-frequency components of the converter can be modeled via the circuit averaging technique, but the resulting equivalent circuits are, in general, time varying and highly nonlinear. Nonlinear stability analysis methods are not appropriate for analysis and control design of such complicated circuits. In this paper a piecewise affine approximation is introduced for modeling of switching circuits. This approach makes the...