A new computer-aided approach to the analysis of CuK converter by using the alternator equations

A novel approach to the computation of the transient and steady-state response of power electronic switching converters is presented. The solution exhibits precision and reflects the continuous character of the converter waveforms. The key to the approach is the extraction of the switching elements (transistors, or transistor and diode, operated as synchronous switches) in a time-varying two-port called an alternator. The remaining part of the converter is linear and time-invariant; it can be described, in the complex frequency domain, by a system of modified nodal equations. The constitutive equations of the alternator are added, providing a global model of the cyclically switching circuit in the s-domain. The converter is analyzed using the Laplace transform. The modified nodal equations of the converter are solved, and the inverse Laplace transform of their solutions is found. The time-domain solutions together with boundary conditions for cyclical operation of the converter are used for the computer-aided calculation of the transient and steady-state response. The method is applied to a coupled-inductor Cuk converter operating in a continuous conduction mode in which the transient state is due to a step-in-line input voltage