Search

An exact algorithm for computing the transient response and the steady-state of DC-to-DC converters containing three reactive elements is proposed. The procedure is 'top-down' and automatable; it starts from a general, symbolic formulation and works down to the actual circuit. The method is applied to the analysis of the boost-buck converter operating in both continuous and discontinuous conduction modes. The basic circuit considered for the boost-buck converter contains mutual coupling between the input and output inductors, DC resistances of the inductors and on-resistance of the switching elements, but no load capacitor. The influence of the mutual inductance on the currents ripple is studied. The results are compared with the response, computed using a numerical method, of the boostbuck converter containing a load capacitor. [ABSTRACT FROM AUTHOR]

A general, computer-aided analysis of power electronic circuit dynamics is proposed. An automatic generation of dynamic models from a circuit specification is the starting point for a symbolic, automatable, exact, ‘top-down’ procedure, that contrasts with circuit-specific analyses. The algorithm is suitable for analysing any converter containing two reactive elements, covering the common switching power stages: buck, boost, buck-boost converters. The method is illustrated by application to the computation of the transient response of a boost converter; the computer results are compared with those obtained by applying the ‘state space averaging’ method and with laboratory results. [ABSTRACT FROM AUTHOR]

A state-space averaging description of a non-linear boost converter, operating in the discontinuous conduction mode, is used to obtain the ‘equivalent’ duty ratio to output voltage, respectively line voltage to output voltage transfer functions. The coefficients of both of them may vary within some intervals due to the variation of the converter parameter values. Feedback compensators of a switching regulator in which the converter is incorporated are designed such as (a) the start-up transient response lies within imposed specifications despite parameter values and load variation, and (b) the output voltage is kept constant regardless of any variation of input voltage. [ABSTRACT FROM AUTHOR]

A feedback system for controlling the speed of a separately excited DC motor supplied from a 3-phase semi-converter circuit is presented. The electronic feedback structure is designed to assure that, in the starting transient state, the motor speed climbs from zero to its steady-state value within specified ‘customer’ bounds. This has to be achieved despite random variations in the characteristics of the supply voltage, of the motor and of the converter, and despite uncertain values of the load, keeping at the same time the starting current peak below a dangerous level. When feedback is applied, the system becomes highly non-linear; but owing to its quantitative approach, the design algorithm uses no small-signal linearizations. [ABSTRACT FROM AUTHOR]