Motor for Aerospace Actuator Systems

next generation aircraft, based on the More Electric design. Electromechanical act increased acceptance as they are becoming more and more safety health management purposes of EMA, reliable and representative simulation models are needed in order to identify failure of the Permanent Magnet Synchronous Motor (PMSM), also kwon as Sinusoidal Brushless Motor. The choice of the multi domain simulation is necessary to improve the si in numerical models and that are mostly used for prognostic analyses of electromechanical actuators. Key 1 In the last few years, the interest in brushless motors has increased because of their advantages compared with traditional brushed motors. The need of improvement in the design of electric motors was first reported during in World War II: in fact, at about 30000 ft, a rapid brush wear occurred [1 exploration, the brush problem became crucial due to the outgassing phenomena. Brushless motors have been designed to ov disadvantages: the electronic commutation, which is made possible by using electronic switches, replaces the mechanical commutation based on carbon made brushes. research activity focused on modelling of the PMSM for electromagnetic aerospace actuator systems for future diagnostic and prognostic applications. For this purpose, short circuit and static eccentricity failure conditions will be implemented in the developed PMSM mode Furthermore, the developed model takes into account dry friction and it overcomes the typical limitations (e.g. simplifying assumptions such as the superposition of the effects) which are unable to assess nonlinear effects arising from failure condition multi development of simulation algorithms properly sensitive to faults. Introduction -Words: -domain numerical method which allows the This study shows the firs results of our s. This purpose is achieved by means of a The interest in electromechanical actuators (EMA) has been growing because of the development of t s. This paper presents a multi domain model of EMA and it focuses on the numerical modelling PMSM, Electromechanical Actuator (EMA), Prognostics, PHM, Numerical Model M. D. L. DALLA VEDOVA P. MAGGIORE M. SCANAVINO Numerical Modelling of Sinusoidal Brushless high altitude strategic bombing matteo.dallavedova@polito.it, matteo.scanavino@gmail.com Motor for Aerospace Actuator Systems Department of Mechanical and Aerospace Engineering 3]. Later on, during space ercome the brushed motor Corso Duca degli Abruzzi 24 the numerical Politecnico di Torino ITALY l. mplifying hypotheses that are typically considered 2 Flight control systems allow to con dynamic: this is made possible by means of the proper actuation of the flight control surfaces. The aerodynamic forces, exerted on the flight control surfaces, will result in the aircraft rotation around one of the three body axes decades, fl hydromechanical or electrohydraulic in recent years, the electromechanical systems are gradually asserting (e.g. UAVs, secondary or stand by systems) systems, EMAs off weight is reduced, maintenance is simplified and hydraulic fluids, which are often contaminant, flammable or polluting, can be eliminated. reasons, as reported in [4], the use of actuation systems based on EMAs is quic several fields of aerospace technology. – EM Flight Control Actuators Fig. 1: 10129, Turin -critical actuation devices: for prognostics and Schematic of the considered EMA system ight control actuators were generally . Indeed, w er many advantages: overall uators have been gaining ith respect to hydraulic kly increasing in trol the aircraft but, especially ; in the last For these WSEAS TRANSACTIONS on POWER SYSTEMS M. D. L. Dalla Vedova, P. Maggiore, M. Scanavino E-ISSN: 2224-350X 102 Volume 12, 2017 for primary flight control, is presented. The EMA system is composed by: 1. 2. 3. 4. 5. 6. 3 The authors’ models implement the motor features only (rotor speed control loop and related reference current controller, pulse inverter, electromagnetic model of the stator circuit and related electromechanical model, internal sensors and considered faults). composed by five subsystems: 1. 2. 3. In Fig. 1, an electromechanical actuator scheme, an actuator control elect the feedback loop, by comparing the commanded position (FBW) with the actual one; it elaborates the corrective actions and generates the reference current ( a Power Drive Electronics (PDE) that regulates the electrical power system to the electric motor; an electric motor, often a type a gear reducer that decreases the motor angular speed and increases its mechanical torque; a system that transforms rotary motion into linear motion: ball screws or roller screws are usually preferred because a conversion with higher efficiency can be performed; a network of sensors that are used to close the feedback loops (current, motor spee position) controlling the whole actuation system (reported in Fig.1 as RVDT). Proposed PMSM Numerical M Fig. 2: Block diagram of the EMA numerical model The proposed model is shown in Fig. 2 and it is W_ref motor speed; PMSM Motor Controller Model actuator control electronics closing loops and generat PMSM Motor ElectroM the power drive electronics and the sinusoidal PMSM electromagnetic behaviour. Furthermore, it evaluates the mechanical torque developed by the electrical motor as a function of the voltages generated by the three ; : input block that generates the reference I_ref);