Design and implementation of a linear motor for multi-car elevators

The multi-car elevator system is a revolutionary new technology for high-rise buildings, promising outstanding economic benefits, but also requiring new technology for propulsion, safety and control. In this paper we report on experimental results with new components for linear motor driven multi-car elevators. We show that linear synchronous motors with optimized design and with our new safety and control system can be considered as core components of a new generation of elevator systems. The main new results concern the development of a safety system integrated into the propulsion system, the design methodology of a linear motor optimized for the multi-car elevator task, and the motion control system that is expected to be usable for extra high-rise buildings

Linear motor for multi-car elevators, design and position measurement

Multi-car elevator is an emerging technology consisting of two or more elevator cars moving independently in an elevator hoistway, which has become more appealing as building heights increase. In this paper, the design and drive methodologies for a linear motor driven multi-car elevator system with independently moving cars is introduced together with experimental results. Additionally, a safety method developed for the linear motor elevator and the conditions necessary for its proper operation are discussed. The new results introduced in this paper are in the areas of the design method of the linear motor for multi-car elevator system, and the preliminary results for the position measurement system

Characteristics and Optimization of a PMLSM for HTS Magnetic Suspension Propulsion System

¾Permanent magnet (PM) linear synchronous motors (PMLSMs) can be integrated with a high temperature superconducting (HTS) magnetic suspension system to be used in such as electromagnetic aircraft launcher and maglev transportation which have a levitated object moving on a long linear track. This paper presents the design and electromagnetic characteristic analysis of a long-primary single-sided PMLSM for a HTS bulk-PM guideway repulsion magnetic suspension propulsion system. Based on the characteristics and performance analysis of the PMLSM, a new type of HTS suspension propulsion system driven by a double-sided PMLSM with an optimal PM structure is then proposed. The running characteristics of the linear propulsion systems are studied through finite element analysis (FEA) with comprehensive performance results obtained for practical development

Multi parametric model predictive control based on laguerre model for permanent magnet linear synchronous motors

The permanent magnet linear motors are widely used in various industrial applications due to its advantages in comparisons with rotary motors such as mechanical durability and directly creating linear motions without gears or belts. The main difficulties of its control design are that the control performances include the tracking of position and velocity as well as guarantee limitations of the voltage control and its variation. In this work, a cascade control strategy including an inner and an outer loop is applied to synchronous linear motor. Particularly, an offline MPC controller based on MPP method and Laguerre model was proposed for inner loop and the outer controller was designed with the aid of nonlinear damping method. The numerical simulation was implemented to validate performance of the proposed controller under voltage input constraints

Model of a Permanent Magnet Synchronous Linear Motor for an Urban Transport Electric Vehicle

Proceeding of: EMS 2015 (2015 IEEE European Modelling Symposium): UKSim-AMSS 9th IEEE European Modelling Symposium on Computer Modelling and Simulation, Madrid, Spain, 6-8 October 2015Also available in: International Journal of Simulation Systems, Science & Technology (IJSSST), (2016), 17(33), pp. 5.1-5.7This work proposes a new linear motor for an electric bus propulsion system. The vehicle is powered by a new topology of permanent magnet synchronous linear motor. The slider of the motor is integrally attached to the floor of the vehicle to propel. The motor is fed with an alternating voltage conveniently applied to a three-phased stator coils which are distributed in the rails that attach the vehicle travel. Therefore, the motor requires no energy storage system. A set of permanent magnets located on the slider and disposed in Hal Bach array, maximize thrust force. The new slider topology is able to reduce the thrust ripple, while maintaining its average value. At the same time it reduces the normal force, which in this type of motor with ferromagnetic slotted stator, is an attraction force. The study of the dynamic behavior of electromagnetic forces concerning the movement of the slider on the stator is shown as well as the motor structural design. A 3D Finite Element simulation tool is used.Publicad

Modeling PM Rotary-Linear Motors with Twin-Stator Using 3D FEMM

A rapid growth of automatization nowadays requires electric machines to be adjusted to any technological process. Therefore, a need in machines with two degrees of mechanical freedom (TDMF), which can operate rotationally and linearly, is relatively large. This thesis is directed on the design and study of performance of PM (permanent magnet) rotary-linear synchronous motors with twin-armature as a new type of electric machines which can perform linear, rotational and helical movements. Three stator versions are considered, namely: stator with rotary and linear armatures, two rotary armatures, and two linear armatures. The rotors have PMs skewed with respect to the axial direction. An analysis of motor performance and an influence of PMs skewing on torque and axial force as well as cogging torque are considered. Calculations are based on 2D and 3D FEM (Finite Element Method)

Vision applications in agriculture

From early beginnings in work on the visual guidance of tractors, the National Centre for Engineering in Agriculture has built up a portfolio of projects in which machine vision plays a prominent part. This presentation traces the history of this research, including some highly unusual topics

Method to Control Multiple Segmented LLSM without Position Encoder

In recent years long stator linear synchronous motors (LLSM) started to replace the typical rotating to linear converters like belts, chains, screw systems, pulleys, disks and so on. With LLSM a lot of drawbacks in the machine concepts and design can be prevented. For long tracks, reducing reactive power and individual control of numerous moveable units, the track is segmented in several fed stator units. Because of the LLSM construction an operation with a physical position encoder is not desirable. For that reason position observers should be used instead. In this paper a method to control the multiple segmented LLSM without position encoder is proposed. The special behaviour during entrance and exit of one moveable unit in an active stator segment is described and the control concept via a master slave relationship is proposed. Experimental results are presented to demonstrate the performance and feasibility of the proposed method

Automated soil hardness testing machine

This paper describes the design and performance of a mechatronic system for controlling a standard drop-hammer mechanism that is commonly used in performing outdoor soil or ground hardness tests. A low-cost microcontroller is used to control a hydraulic actuator to repeatedly lift and drop a standard free-falling weight that strikes a pipe (sampler) which is pushed deeper into the ground with each impact. The depth of the sampler pipe and position of the hydraulic cylinder are constantly monitored and the number of drops, soil penetration data and other variables are recorded in a database for future analysis. This device, known as the “EVH Trip Hammer”, allows the full automation and faster completion of what is typically a very labour-intensive and slow testing process that can involve human error and the risk of human injuries