Sliding-mode approach to control design for induction motor drive fed by a three-level voltage-source inverter

Abstract

A novel sliding mode control for the induction motor (IM) fed by three-level voltage-source inverter (3L-VSI) is proposed in this paper. The "classical" results of sliding-mode theory were extended on the actual variable structure system with more then 2 m variable structures (m is the control space order) by using an original two-step design procedure that allows separately to use the nonlinearity of the IM and the switching character of the 3LVSI. The based on this design procedure original control algorithm that includes a choice condition for 3L-VSI input dc link voltage and a switch table for the 3L-VSI semiconductor switches is designed. The main advantages of such approach are given as follows: the control design is simpler and more graphical; the control system has such advantageous characteristics of the control plant with sliding mode control as high dynamic, low sensitivity to disturbance of both the load and the to plant parameter variations; the requirements to the quality of the input dc-link voltage and as a result to the dc-line filter capacitor are reduced; the measurement precision of the stator flux position is within ( 6) . Simulation results are presented to validate the theoretical analysis and demonstrate the performance of the proposed control.

Sliding mode control technique for an induction motor drive supplied by a three-level voltage source inverter

“…The transfer from the control quantity U F to the real output voltages of a 3LVSI is based on the fact, that the choice conditions of the magnitudes of the formally entered controls in the stator-flux rotating-frame obey the inequalities (12), (13). It is obvious, if designing the real discontinuous voltage control thus that the voltages projections on the axes of the stator-flux rotating frame have their marks and sizes, which are needed by the control algorithm with the formally entered controls, the sliding mode on crossing before the chosen surfaces will take place.…”

“…Such a control (3LVSI dc-link voltage value and control table) guarantees that the system will reach -from the initial condition selected in (12), (13) -the sliding Table 3. Switch controls II sgn (6) in finite time and remains on it and will be robust against the load value variation, the selected uncertainty of the system parameters, of the 3LVSI dc-link voltage and of the estimation of the stator-flux angle position.…”

“…On the other hand, SM control could be successfully used for solving the control task in the frame of the principal operational mode of this class of variablestructure systems, due to its property of order reduction and its low sensitivity to disturbances and plant parameter variations [12]. The aim of this paper is to extend the SM technique to a the class of nonlinear control plants, dedicated especially to high-power drives: IM drives supplied by 3LVSIs.…”

A PWM Strategy for the Minimisation of Losses in a 3-level T-type Voltage Source Inverter

“…This is due to active support from manufacturers offering new power semiconductor modules which are specialised for implementation of a 3-level inverter topology in electrical power conversion installations. Nowadays, the applications of this topology include high-power and photovoltaic (PV) converters, uninterruptable power sources (UPS) and precision power supplies [1]- [3]. Compared to other power electronic topologies the 3-level inverter has the following well-known advantages:…”

“…Then, the duty cycles are to be evaluated according to (3). This gives enough information for evaluation of the losses for all sets of the voltage reference left for this moment.…”