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

Modular switched reluctance machines to be used in automotive applications

In the last decades industry, including also that of electrical machines and drives, was pushed near to its limits by the high market demands and fierce competition. As a response to the demanding challenges, improvements were made both in the design and manufacturing of electrical machines and drives. One of the introduced advanced technological solutions was the modular construction. This approach enables on a hand easier and higher productivity manufacturing, and on the other hand fast repairing in exploitation. Switched reluctance machines (SRMs) are very well fitted for modular construction, since the magnetic insulation of the phases is a basic design requirement. The paper is a survey of the main achievements in the field of modular electrical machines, (especially SRMs), setting the focus on the machines designed to be used in automotive applications

Quantitative comparison of permanent magnet linear machines for ropeless elevator

Paper no. YD-026263This paper presents a quantitative comparison of three topologies of double-sided long-stator type permanent magnet linear machines (PMLMs) as possible candidates for the ropeless elevator propulsion system. First, the parameters of each PMLM topology are designed using the same criteria. Then the finite element method (FEM) is employed to evaluate the performance of each topology. Specifically, the translator mass, propulsion forces, detent forces, and no-load EMFs are analyzed and compared. The quantitative comparison results show that the Halbach array PMLM configuration is preferable for the ropeless elevator application because of its small detent force as well as low total mass. © 2015 IEEE.postprin

Elevator regenerative energy applications with ultracapacitor and battery energy storage systems in complex buildings

Due to the dramatic growth of the global population, building multi-story buildings has become a necessity, which strongly requires the installation of an elevator regardless of the type of building being built. This study focuses on households, which are the second-largest electricity consumers after the transportation sector. In residential buildings, elevators impose huge electricity costs because they are used by many consumers. The novelty of this paper is implementing a Hybrid Energy Storage System (HESS), including an ultracapacitor Energy Storage (UCES) and a Battery Energy Storage (BES) system, in order to reduce the amount of power and energy consumed by elevators in residential buildings. The control strategy of this study includes two main parts. In the first stage, an indirect field-oriented control strategy is implemented to provide new features and flexibility to the system and take benefit of the regenerative energy received from the elevator’s motor. In the second stage, a novel control strategy is proposed to control the HESS efficiently. In this context, the HESS is only fed by regenerated power so the amount of energy stored in the UC can be used to reduce peak consumption. Meanwhile, the BES supplies common electrical loads in the building, e.g., washing machines, heating services (both boiler and heat pump), and lighting, which helps to achieve a nearly zero energy building

Advanced Control of the Permanent Magnet Synchronous Motor

The electrical machines are the core of the electrical drives. By introducing the vector control techniques for the alternative current machines, the high performances in drive systems are attained. One on the alternative current machines is the permanent magnet synchronous motor (PMSM). Due to their advantages, it becomes a very popular solution in the electrical drive field. In this chapter, an optimal control solution applied on the PMSM based on the Riccati solution is developed by the author. The objectives of the optimal control drive system are regulation, stability, robustness to the load disturbance variation and the energy reduction. Comparative with the conventional cascaded control, the proposed solution conducts up to 10% to energy efficiency improvement in transient regimes. The efficiency improvement depends on the chosen weighted matrices. Both the conventional and optimal controllers are implemented in Matlab-Simulink. The real-time solution based on the dSpace platform is provided

Super-capacitor energy storage system to recuperate regenerative braking energy in elevator operation of high buildings

In operating phases of elevators, accelerating, braking modes occur frequently, so braking energy recuperation of elevators has contributed considerably to decrease the total electric energy consumption for operating elevators in multi-floor buildings. In this paper, the supercapacitor energy storage system is used to recover regenerative braking energy of elevators when they operate down full-load and up no-load, reducing fluctuation of voltage on DC bus as well. Therefore, super-capacitor energy storage system (SCESS) will be parallel with line utility to recuperate regenerative braking energy in braking phase and support energy for acceleration phase. The surplus energy will be stored in the supercapacitors thanks to a DC-DC converter capable of exchanging energy bidirectionally in buck/boost modes, and designing control strategy including two control loops. Inner loop-current loop: controlling charge/discharge process of supercapacitors by current iL complying with operation characteristic of elevator; Outer loop-voltage loop: managing UDC-link at a fixed value. Simulation results with elevator system of the ten-floor building, Hanoi, Vietnam installed SCESS have been verified on MATLAB Simulink, SimPowerSystem with saving energy level about 30%

Machine generated vertical vibration in elevators

Vertical vibration deteriorates passenger comfort during an elevator travel. The drive system is a source of vertical vibration as well as the source of energy of the system. This report presents the results of a study of car vertical vibrations generated at the drive system in elevator installations. The elevator system can be considered as a translating assembly of inertia elements coupled and constrained by one-dimensional slender continua. The inertia elements are the car assembly, the counterweight, the traction sheave and other rotating components of the system. According to the roping arrangement and to the ratio of the tangential velocity of the traction sheave to the velocity of the car, the traction elevators can be classified as roped 1:1 or multiple reeving systems: the types examined in the present work are 1:1 and 2:1 traction elevators. Distributed- and lumped-parameter models (DPM and LPM respectively) are developed to calculate the natural frequencies and mode shapes of stationary elevator systems and their results compared. A non-stationary model of a 1:1 roping configuration elevator is developed as well to simulate the elevator acceleration response. The model accommodates the drive system dynamics: it includes the electric motor and the torque and velocity controllers, which ensure that the car follows a prescribed kinematic profile, so that good ride quality of the elevator is achieved. The machine parameters are computed by means of the Finite Element Method simulation software FLUX. With respect to the carcounterweight-sheave-ropes assembly, a LPM and a novel DPM are developed. The elevator dynamics represented by the DPM is described by a partial differential equation set that is discretised by expanding the vertical displacements in terms of the linear stationary mode shapes of a system composed of three masses constrained by the suspension rope. The models are implemented in the MATLAB/Simulink computational environment and the system response is determined through numerical simulation. It is shown that the LPM forms a good approximation of the DPM. Experimental tests are carried out on laboratory models. The elasticity modulus of the rope and the friction coefficients at the guide rail contact and at the machine are estimated. The acceleration response at the suspended masses and at the drive machine, the machine shaft velocity and the three phase current intensities supplied to the machine are measured during several travels. The machine torque is estimated from the current intensities. The computed and measured accelerations are compared either in time or frequency domain and it is demonstrated that the elevator car vibrates at frequencies generated at the machine, especially when they are close to the system natural frequencies. The proposed simulation models can be used as design and analysis tools in the development of high-performance elevator systems