Suppression of Undesired Attractors in a Self-Oscillating H-Bridge Parallel Resonant Converters Under Zero Current Switching Control

Abstract

Resonant converters under zero current switching control strategy can exhibit coexistence of attractors, making it difficult the startup of the system from zero initial conditions. In this paper, the problem of multiple coexisting attractors in parallel resonant converters is addressed. Appropriate modifications of the switching decision with the aim of converting undesired attractors into virtual ones are proposed. A suitable control signal is generated from the state variables of the system and used to adjust the switching decision. Numerical simulations corroborate the proposed solutions and the simplest one was finally verified by measurements from a laboratory prototype.

Delay effects on the limit cycling behavior in resonant inverters with state feedback

“…Then, the canonical form of the system taking into account the time delay in the switching decision can be summarized as follows Proposition 2 System (1)-(2) with a fixed time delay T d in the switching action can be reduced to the piecewise linear field defined in (11), with the switching function h τ as given in (16) and the matrix A and the vector b defined in (13).…”

“…The parameter condition β < β hc (γ) is the advisable one for a standard application of the inverter, because this condition implies that the origin of the state-space, which is the likely starting point for the dynamics, is not on on the basin of attraction of the equilibrium points. Moreover, to ensure that the equilibrium points are not real attractors for the switched system, the factor g C in the state feedback control should be chosen to get, at least during some initial time interval, a parameter value β < 0 [16].…”

Hybrid Control of Self-Oscillating Resonant Converters

“…Different from the two-controllers scheme of [7], our self-oscillating solution only requires one controller. Moreover, our self-oscillation mechanism overcomes the stringent bound on the quality factor assumed in [12], [14]: our only mild requirement on the quality factor is that the dynamics of the resonant tank must be underdamped. In [22], we also discussed in depth the PRC configuration, showing a desirable dependence of the output amplitude and frequency on the reference input θ.…”

“…The stability of the induced limit cycle with the switching mechanism for the start-up is analyzed in [8] with a Poincaré map. Further developments in that direction include [9]- [11] that analyze series resonant converters with switched affine models, followed by [12]- [14] that demonstrate that state-plane based methods can outperform the dynamics of conventional approaches. Nonetheless, the above state-plane control solutions also have limitations, one of them (resolved here) being the assumption that the resonant tank has a sufficiently high quality factor Q [12], [14].…”

Multistability and Its Control by the PWM Carrier Signal Modulation in a DC Electric Drive System

“…Proceeding with the problem of controlling multistability, the diversity of techniques is classifed into two main categories, depending on whether the control (i) drives the system to the desired mode by an external perturbation [45][46][47] or (ii) forces the collapse of the undesired modes [48][49][50]. Te one studied in the work can belong to both categories within the above classifcation (depending on the particular implementation).…”