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In this paper, a terminal sliding mode (TSM) controller is designed for boost converter with purpose of robustness and better response against circuit nonlinearities and disturbances. Instead of using the commonly used average model or switching model for current-mode controlled (CMC) boost converter, a novel energy storage function (ESF) model is proposed for TSM controller, which contains all of the nonlinear elements of inductor current and capacitor voltage and further converges the both to the zero, unlike the CMC control ignoring the transient control of capacitor voltage. By adopting TSM instead of the traditional linear sliding mode (LSM), the system can track the given output voltage with faster response due to its finite time convergence. Meanwhile, an exponential reaching law is designed for TSM controller to eliminate the unexpected chattering phenomenon. Simulation results with comparison of the traditional CMC LSM control can prove the better control performance of the proposed scheme.

In order to solve the problems such as lower control performances and unfixed switching frequency in the traditional sliding mode control (SMC) of DC-DC buck converter, a novel modulation method with constant switching frequency is proposed on the basis of non-singular terminal sliding mode (NTSM) and duty cycle control. The averaging state model is established and the duty cycle is controlled to produce the periodic triggering pulses. A NTSM controller is designed and the unified stability condition of buck converter for the both cases of switching ON and OFF is also deduced. Simulation results validate the proposed method.

This paper presents a novel terminal sliding mode (TSM) control scheme with double closed-loop structure of capacitor voltage and inductance current for the stability control of DC-DC buck converter. In order to satisfy the different performance demands of capacitor voltage and inductance current, a TSM controller and a linear sliding mode (LSM) controller is designed separately. For the former, TSM controller can track the given output voltage with fast response speed due to its finite time convergence and then output the reference inductance current; while for the latter, it can track the reference inductance current and then control the ‘on/off’ of the power switch. The stability condition in the case of power switch ‘on’ and ‘off’ can also be deduced. Simulation results with comparison of those of traditional single-loop LSM controller can validate the proposed scheme.

This paper proposes a novel continuous non-singular terminal sliding mode (NTSM) control scheme for permanent-magnet synchronous motor (PMSM) speed system with unknown load torque. Utilizing the concept of relative degree, a continuous NTSM control method is proposed and applied to the decomposed speed and current double closed-loop vector control system, which features of finite-time convergence property proved by the comparison with the commonly used super-twist algorithm and second-order NTSM method. Meanwhile, a Luenberger observer is designed to estimate the unknown load torque. Simulation results shows that the proposed control scheme possesses the advantages of fast transient responses, no over-shoot and resistance to load disturbances.

This paper proposes an optimized continuous non-singular terminal sliding mode (NTSM) control scheme for a class of two-link flexible manipulators with uncertain model parameters. Firstly the original system is transformed into the controllable minimum phase system using output redefinition with purpose to change its non-minimum phase dynamics and the corresponding input-output subsystem and zero dynamic subsystem can be obtained. Then a novel continuous NTSM controller by combining NTSM and high order sliding mode (HOSM) on the basis of relative degree and a genetic algorithm is designed to obtain its optimal control performances, respectively. Simulation results illustrate the correctness of the proposed scheme.