Slawomir Stepien

• Professor
• PhD DSc Eng at Poznań University of Technology

This paper presents modelling of a squirrel-cage induction motor and an optimal control method based on suboptimal control for nonlinear systems to minimise consumed energy and power losses in an induction motor drive. A coupled motor model with optimal control as a closed-loop integrated system is proposed. For modelling of the squirrel-cage async...

The paper presents a study of the performance and development of unmanned ground vehicles (UGVs), establishing mathematical and numerical models of the chassis system. The model analysis is performed by 3D software package SolidWorks 2018 with finite element discretization. The mesh modelling and analysis are focused on studying the strength and st...

In the paper, a study of the performance of unmanned ground vehicle (UGV), establishes numerical simulation model of the chassis system by three-dimensional software and finite element analysis software. Based on the numerical modelling and analysis, the work focuses on study of the strength and stiffness of the vehicle's chassis and researched the...

Over the past few years, there has been an increasing fascination with electric unmanned aerial vehicles (UAVs) because of their capacity to undertake demanding and perilous missions while also delivering advantages in terms of flexibility, safety, and expenses. These UAVs are revolutionizing various public services, encompassing real-time surveill...

Over the past few years, there has been an increasing fascination with electric unmanned aerial vehicles (UAVs) because of their capacity to undertake demanding and perilous missions, while also delivering advantages in terms of flexibility, safety, and expenses. These UAVs are revolutionizing various public services, encompassing real-time surveil...

Modern and innovative de-icing sprinkler-flusher airport machines are now equipped with special arm system. The vehicle arms are manufactured for removal of ice or frost from the surfaces of the airports runways and areas by pouring designated for that chemicals substances. The paper presents a study of the performance of airport de-icing vehicle’s...

In the paper, a new cascade control system for an autonomous flight of an unmanned aerial vehicle (UAV) based on Proportional–Integral–Derivative (PID) and finite-time State-Dependent Riccati Equation (SDRE) control is proposed. The PID and SDRE controllers are used in a hybrid control system for precise control and stabilization, which is necessar...

This paper presents modeling and infinite-time suboptimal control of a quadcopter device using the state-dependent Riccati equation (SDRE) method. It establishes a solution to the control problem using SDRE and proposes a new procedure for solving the problem. As a new contribution, the paper proposes a modified SDRE-based suboptimal control techni...

Methods for solving non-linear control systems are still being developed. For many industrial devices and systems, quick and accurate regulators are investigated and required. The most effective and promising for nonlinear systems control is a State-Dependent Riccati Equation method (SDRE). In SDRE, the problem consists of finding the suboptimal so...

Purpose The purpose of the paper is to present modeling and control of a nonlinear mechatronic system. To solve the control problem, the modified state-dependent Riccati equation (SDRE) method is applied. The control problem is designed and analyzed using the nonlinear feedback gain strategy for the infinite time horizon problem. Design/methodolog...

The infinite time suboptimal control problem for continuous-Time nonlinear positive systems is formulated and solved. A solution to the problem using input-state linearization and state-dependent Riccati equation method (SDRE) is established, a procedure for solving the problem is proposed and illustrated with a numerical example.

A new structure to design observers for linear systems is presented in this work. The key step is the construction of two layers where the first consists of multiple observers and the second connects them providing the weighted estimation state. The main difficulty is to find a new feedback which is responsible for control weights. To define observ...

Ionic Polymer Metal Composite (IPMC) is an electroactive polymer (EAP) and a promising candidate actuator for various potential applications mainly due to its flexible, low voltage/power requirements, small and compact design, and lack of moving parts. Although widely used in industry, this material requires accurate numerical models and knowledge...

This paper addresses the issue of estimating current waveforms in a switched reluctance motor required to achieve a desired electromagnetic torque. The methodology employed exploits the recently-developed method based on the transformation from the time to the position domain. This transformation takes account of nonlinearities caused by a doubly-s...

Purpose This paper aims to present a nonlinear finite element model (FEM) of the Brushless DC (BLDC) motor and the application of the optimal linear–quadratic control-based method to determine the excitation voltage and current waveform considering the minimization of the energy injected to the input circuit and energy lost. The control problem is...

Purpose Brushless DC (BLDC) motors are commonly used in the industry. The improvement of power switching electronic elements, especially integrated circuits, has led to the development and improvement of control strategies. The purpose of this paper is to apply the well-known LQR control method for the highly accurate model of the BLDC motor, whic...

An optimal control theory for linear quadratic finite time horizon problem is presented and combined with distributed parameters model of the BLDC (BrushLess Direct-Current) motor. Method appropriateness for minimization of the phase current control error and energy delivered to the drive is proven. The paper focuses on finding the best weighting c...

The optimal control problem for continuous-time nonlinear systems with nonlinearity in state is formulated and solved. A solution to the problem using state-dependent Riccati equation method (SDRE) is established, procedure for solving the problem is proposed and illustrated with a numerical example.

The presented paper proposes a novel control method of Permanent Magnet Synchronous Machine. Thanks to a recent technique called adaptive backstepping, adjustment of all motor parameters is obtained considering well known dq model. Furthermore, the introduction of a new trajectory generator gives the possibility to limit the reference current witho...

An optimal control theory based method is presented aiming at minimizing the energy delivered from source and the power loss in a stepper motor circuit. A linear quadratic current regulator with an infinite time horizon is employed and its appropriateness for this type of a problem explained. With the purpose of improving the accuracy of the contro...

The paper presents a study on a novel steady state solver for modelling rotating electromechanical devices. As the new contribution, the transformation of the system from time to position domain is exploited to improve the efficiency of computation. The proposed methodology is well suited to optimizing the current or voltage waveforms to drive the...

This research presents a 3D FE method for the simulation of the variable reluctance stepper motor dynamics. The proposed model is used to obtain the optimal minimum energy control law that minimizes the energy injected by the controller. The method is based on the strong coupling of field - circuit equations and extended to eddy current, motion and...

Recent years have brought important changes in engineering education, especially in electrical and computer engineering. Along with new equipment and modern electronics, there are new opportunities in the automation control. This paper presents a hand motion controller, which measures the orientation of the upper limb of a man in three dimensional...

This paper presents the method of modeling and numerical simulation of a hybrid stepper motor. The problem is solved by the electromagnetic field modeling, using the time-stepping finite element method. Circuit equations are coupled with field equations creating one global system of non-symmetric equations. The mechanical motion of the rotor is det...

In this paper a method of modeling and numerical calculation of the back electromotive force in the three phase BLDC motor using the finite element technique is presented. In analyzed model the electromagnetic field model considering permanent magnets is coupled with motion model and solved together at discrete time steps. The back electromotive fo...

A method of modeling and numerical simulation of a minimum energy control of the switched reluctance motor using time stepping finite element (FE) technique is presented. In proposed model, the nonlinear electromagnetic field equations and the circuit equations are strongly coupled and solved together with motion equation at each time step. The non...

This article presents a study on the novel method of model reference adaptive control (MRAC). As a new contribution, the derivative action is included into MRAC control to improve the controller performance and efficiency. The stability is analysed using a recent technique called immersion and invariance. The simulations of derived laws are present...

Reluctance stepper motors are commonly used in many cost-sensitive industrial and consumer applications, however they are affected by a large torque ripple, due to construction and phase unbalancing. This, in turn, may cause large vibrations on the load, especially in those systems with flexible elements. This research presents a technique of dynam...

This research presents a new adaptive speed controller for the brushless DC motor. The methodology of model reference adaptive control is applied to a novel model of BLDC motor. This novel model provides the possibility to compensate the torque ripples and load torque. The system stability is proven using Lapunov function.

Application of optimal current driver for the torque control of BLDC motor This research presents the novel control strategy of the brushless DC motor. The optimal current driver is designed using Linear Quadratic Regulator and feedback linearization. Additionally, the current reshaping strategy is applied to control the motor torque. Thus, the tor...

Purpose – The purpose of this paper is to present a method of modeling the variable reluctance stepper motor using the time‐stepping finite element technique. The proposed model is used to minimize the step response overshoots considering the stator and rotor tooth geometry. Design/methodology/approach – A strongly coupled field‐circuit model cons...

Purpose – The purpose of this paper is to present a method of modeling the variable reluctance stepper motor using the time‐stepping finite element technique. The proposed model is used to obtain the optimal control law for the input circuit solving the linear‐quadratic problem. Design/methodology/approach – A strongly coupled field‐circuit model...

An inductance lookup table application for analysis of reluctance stepper motor model This research presents a method of modeling and numerical simulation of a reluctance stepper motor using reduced finite-element time-stepping technique. In presented model, the circuit equations are reduced to non-stationary differential equations, i.e. the induct...

A method of modeling and numerical simulation of a switched reluctance motor employing 2D and 3D finite element models is presented. In proposed model, the electromagnetic field equations and the circuit equations are strongly coupled and solved together with motion equation at each time step. The comparison of the motor dynamics using 2D and 3D ap...

The Finite Element Method (FEM) is widely used to model and simulate electromechanical devices. It enables us to analyze device’s properties and improve its performance. Although, its relevance for electric machine design has been proved, its drawbacks are time consuming calculations. Therefore, it is proposed a novel parallel solver to the FEM mod...

Induction motor analysis employing optimal torque predictor and massive conductor approach This research presents a method for the simulation of the magneto-mechanical system dynamics taking motion and eddy currents into account. The major contribution of this work leans on the coupling the field-motion problem considering windings as the current f...

Purpose – The purpose of this paper is to calculate the electromagnetic torque at a radius of an integration contour for which an optimal value is determined. Design/methodology/approach – To analyze electrical machine dynamics, the electromagnetic torque should be precisely determined. This paper presents a method for calculating the torque, wher...

This paper presents a method of the speed control of the BrushLess DC motor (BLDC). The proposed method is based on the linear quadratic problem and sliding mode control. In the control system, the fuzzy logic controller is applied to obtain its robustness and optimal performance. The BLDC motor model is described using finite element boundary equa...

This paper presents the model of the special class electromagnetic field problem coupled with mechanical motion. In the proposed approach, electromagnetic field equations and motion equation are solved simultaneously at each time step. The 3D model considers current distribution in device windings and eddy current reaction to the exciting coils.

This paper shows the parallel magnetostatic FEM analysis of electrome-chanical devices. The problem of the parallel computing is solved by the time independent electromagnetic field analysis. Presented technique has been used to find the optimal design of brushless DC motor. The goal of the optimization is to obtain the maximum rotor speed at stead...

This paper presents the modular testing system investigating a proper functionality of digital servo amplifiers supporting quality testing process. The system design enables electrical testing of input/output channels and power stages in terms of eventual short circuits, current efficiency and assumed functionality.

The accurate positioning problem of the variable reluctance stepper motor is considered. On the basis of the non-linear distributed parameters model, the PID controller is designed that guarantees execution of the desired angle displacement, feeding back the rotor position signal. Simulations compare the performance of the step response signals inc...

In this paper a method of computing of magnetic forces in systems with permanent magnets is presented. In analyzed model the magnetostatic field problem considers the coil current excitation coupled to the permanent magnet. As a new contribution the global magnetic force calculation of the system is presented. The method of the force computation is...

In this paper a method of modeling and numerical simulation of the variable reluctance stepper motor using the time stepping finite element technique is presented. In analyzed model the magnetostatic field partial differential equations are coupled with rotor motion equation and solved simultaneously in each iterative step. The nonlinearity problem...

In this paper a method of modeling and numerical simulation of the single phase AC motor using the time stepping finite element technique is presented. In analyzed model the electromagnetic field model considering eddy currents is coupled with motion model. As a new contribution the magnetic torque calculation of the rotor made from two different m...

This research presents a methodology to parallel computations of the finite element models of electromagnetic systems excited from voltage source. In the model an electric circuit equations, field equations and motion equation are sequentially coupled. The circuit equations for each phase are calculated parallel using client – server system. Simul...

A finite element - based simulation of the single - phase electromagnetic actuator control including 3D electromagnetic field, circuit and movement model coupling to optimal control is presented. The subject of this paper is to study an optimal control technique that minimises quadratic energy function in the electric circuit. As a new contribution...

In this paper a numerical model and simulation of non-linear field - circuit system dynamics is presented. The system includes electromagnet coupled with two RC circuits. The RC circuit performs a current rise acceleration and improves the electromagnet dynamics. In proposed system a value of capacitance C impact on electromagnet dynamics is numeri...

Parallel computing becomes common tool to accelerate long-lasting electromagnetic computations. In some cases their realization does not bring an expecting gain. In this paper the authors present the results of the simulations from application created in order to show selected anomalies in parallel computing. The way of parallel system implementati...

In this paper an effective approach for parallel computations of multiphase electromagnetic systems is presented. This method is used to accelerate solving of multiphase models using socket interface algorithm. Discussed algorithm has been examined in example of 3D FE three-phase transformer.

Paper presents parallel algorithm used in computation of 3D electromagnetic device with coupling electric and non-linear field equations with mechanical motion equations. The algorithm solves the large sparse systems of linear equation using parallel computing. There is given a numerical example as a model of an electrodynamic relay. The problem is...

This research presents a voltage control method of an electromagnetic levitation device. Finite element method is used to model the device known as Team Workshop Problem 28. Proportional-Integral controller of sinusoidal voltage amplitude ensures a needed levitator position. The levitation device equations and the controller equations are coupled a...

This paper presents an effective scheme for coupling electric circuits with magnetic fields. Indirect coupling on example of transformer and full wave rectifier with filtering system is presented. 3D Transient finite element model of transformer is described by magnetic vector potential A formulation. Non-linear material characteristic of ferrite c...

Purpose – To present modelling and control technique of an electromagnetic actuator. Design/methodology/approach – A 3D modelling technique of voltage‐forced electromechanical actuator takes into account: motion, magnetic non‐linearity and eddy current phenomena. Control problem of closed loop system is described by coupled electro‐magneto‐mechani...

A current control method of an electromagnetic levitation device is studied in the paper. Finite element method is used to model the device known as TEAM Workshop Problem 28. Proportional-Integral controller of sinusoidal current amplitude ensures a needed levitator position. The levitation device equations and the controller equations are coupled...

In this paper is considered modelling of voltage forced electromechanical actuator taking friction and spring stiffness into account. 3D distributed parameters model including eddy current phenomena and magnetic non-linearity is presented. In numerical example a motion of movable armature is presented.

Presents 3D method for the computation of the winding current distribution and power losses of the electromagnetic gear. For a prescribed current obtained from measurement, the transient eddy current field is defined in terms of a magnetic vector potential and an electric scalar potential. From numerically obtained potentials the power losses are d...

Active robot-environment interaction leans on information about state of robot in workspace and environment objects features. The information can be obtained from external sensors. Many advanced sensors are concentrated in grippers or effectors and connected to computer measurement system. In the case of electromagnetic sensors, the computer-sensor...