Modelling and position control of voltage forced electromechanical actuator

Abstract

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-mechanical equations and non-linear PID controller equations. Findings -Presented methodology offers a powerful tool for analysis of control systems with distributed parameters models and may contribute to the improvement of the electromechanical performance of electrodynamic devices. Originality/value -As original contribution a position feedback control using conventional PID controller is applied for iterative determining inverse dynamic problem, that is finding input voltage for a given position of an actuator.

Closed loop voltage control of a solenoid using parallel finite element method

“…In a feedback control system there are different ways of controlling the current of the coil such as proportional-integral-derivative (PID) control (Stępień and Patecki, 2006), optimal control theory (Bernat and Stępień, 2011;Bernat et al, 2014;De Kock et al, 2010), adaptive control, neural network prediction control and fuzzy logic control (Åström and Murray, 2008). In this case the proportional-integral (PI) controller (Åström and Hägglund, 1995;Haemmerich and Webster, 2005;Stępień and Patecki, 2006) has been used, so that the PI controller is enough for the used first-order system. There are many PI control configurations, but the most common implementation of this controller is the feedback-loop with a single input and single output.…”

“…To find the appropriate model of a wide range of electromagnetic devices, the finite element method (FEM) (Bastos and Sadowski, 2003;Kuczmann and Iványi, 2008) is a very useful technique, when the problems with complex geometry cannot be solved by analytical methods. But the finite element model of the physical system is not always enough to replace the state space model of the system (Haemmerich and Webster, 2005) or to use model identification (Stępień and Patecki, 2006;Bernat and Stępień, 2011) or to use results of finite element calculation in the control algorithm (De Kock et al, 2010).…”

An inductance lookup table application for analysis of reluctance stepper motor model

“…An above equations are expressed by impedance matrix, where n = 1 ... 4 (four-phased motor model). The analysis of electromagnetic field constructed as the following boundary value problem [6]:…”

“…Classically, the analysis of field-circuit systems is composed of two parts: the analysis of electric circuits described by differential equations, where magnetic flux is a function of field potentials and magnetic field described by boundary value problem [1,6]. Many researchers propose numerical procedure to investigate the coupled system of equations [5,8].…”

Determination of electromagnetic torque with on‐line computation of the optimal radius of the integration contour

“…The rotor part of the mesh is rotated at each iteration step by the angle determined by the prescribed angular speed. The governing equations of the electromagnetic field are represented by Maxwell's equation in the form of a magnetic vector potential and an electric scalar potential (Stepien and Patecki, 2006): Equation 1 Equation 2 The magnetic vector potential A and the electric scalar potential V are electromagnetic field variables, μ is a permeability, σ represents conductivity, v =ω× r represents speed of the movable element, where the angular speed ω =[0 0 ω ] T is represented by the z‐component only, and j is a current density in the winding. In the prescribed speed case, the rotor displacement is evaluated by solution of the equation defined for the one degree of freedom: Equation 3 where Θ is the rotor displacement and ω is the rotor angular speed.…”