Novel short‐circuit protection technique for DC–DC buck converters

Abstract

This study presents a novel short-circuit protection technique for DC-DC buck converters. The required short-circuit operating frequency is derived in order to avoid the effect of inherent propagation delay in the controller and power transistors. In this design, the short-circuit switching frequency is approximately 31% of the normal value. Simultaneously, the peak current limit is decreased to about 40% of the normal value to lower the power dissipation when a short-circuit event occurs. Once the fault condition is removed, the converters can automatically return to normal operation smoothly by clamping the soft-start signal using the feedback voltage of the output. A buck converter with the proposed technique has been successfully simulated and verified by a 0.6-μm CDMOS technology. The simulation results show that the power loss is only 17.1% of the constant current limit during the prolonged short-circuit situation, which significantly enhances the reliability of the chip. Furthermore, the converter is able to achieve smooth self-recovery as soon as the fault status is released.

Stability analysis and nonlinear current‐limiting control design for DC micro‐grids with CPLs

“…Thus, the roots also represent the equilibrium points of the nonlinear system. Exponential stability at the origin can be investigated via system's (33) corresponding Jacobian matrix (see (36)) , where it is obvious that J 1 has negative eigenvalues since it is lower triangular and the diagonal elements To obtain the reduced model, the roots E and E q are substituted from (35) into (29), yielding (see (37)) , with…”

“…The overcurrent protection as presented in [30,31], guarantees the converter operation and protection of the equipment without violating its technical limitations. Existing strategies are based on protection units such as using additional fuses, circuit breakers or relays [32][33][34]; however, it still represents a challenge to design control methods that ensure an inherent current-limiting property [35][36][37]. Although current-limiting control methods based on saturated PI controllers are often used to guarantee a given upper limit for the current, the shortcomings of these methods have not been completely overcome, e.g.…”

Current-Limiting Droop Control Design and Stability Analysis for Paralleled Boost Converters in DC Microgrids

“…In this framework, the current-limiting property as outlined in [18], [19], guarantees the converter operation and protection of the equipment without violating certain bounds, as imposed by the technical requirements of each device. Despite the existing strategies that are based on protection units such as using additional fuses, circuit breakers or relays [20], [21], the challenge still rests on designing control methods that can ensure an inherent current-limiting property [22], [23], [24]. Although current-limiting control methods based on saturated PI controllers are often used to guarantee a given upper limit for the current, the main drawbacks of these methods are: i) only the reference value of the converter's current is limited, i.e.…”

Design of a synchronous boost DC–DC converter with constant current mode control in MPP

“…Most designers will add the peak current settings, such as 6 A. When the inductor peak current exceeds 6 A, the short circuit protection will be enabled, the chip will be turned off or switch into hiccup mode to restart when detecting the output short load is removed [13].…”