Starting Torque Characteristics Research Articles

Numerical and experimental study on flat roller/cam pair in a two-dimensional piston pump

The two-dimensional piston pump with flat roller/cam transmission mechanism enables high-speed operation, frequent load-carrying start-ups, and rotational direction changes, making it suitable for electro-hydrostatic actuators. This study investigates the rolling friction loss and starting torque characteristics of the friction pair under high-speed and high-load conditions. Numerical simulations show that the flat roller/cam friction pair is unsuitable for elastohydrodynamic lubrication when the roller surface hardness exceeds the cam surface. Experimental results reveal a friction coefficient of 0.0042 during load-carrying start at 1400 N, equivalent to 28 MPa pump load pressure, and 0.001 at 10000 rpm and 1400 N. The study highlights the high transmission efficiency of the designed mechanism, allowing load-carrying start-ups without relying on an oil film.

Loss and Efficiency Analysis of BLDC Motor and Universal Motor by Mathematical Modelling in the Mixer Grinder

The typical mixer grinders are universal motor, which operates on alternating current supply because of the higher starting torque characteristics and easy speed control. The absence of brushes in the Brushless DC (BLDC) motor and noise reduction improves its life and makes it perfectly suited for mixer grinder. The mathematical modelling and experimental demonstration of a conventional universal motor and proposed simulated model of BLDC motor was analysed using the MATLAB/Simulink. The loss and efficiency analysis of the permanent magnet BLDC and universal motor in the application of a mixer grinder are presented in this paper.

Effects of blade configuration and solidity on starting torque of Darrieus wind turbine

This study investigates the effects of blade configuration and solidity of Darrieus wind turbine on the starting torque characteristics. Generally, the configuration of Darrieus wind turbine is divided into Troposkien, parabola, Catenary, Sandia, modified-parabola and straight types. A numerical analysis has been carried out using Multiple Stream Tube (MST) method to investigate the effect of blade configuration and solidity of Darrieus wind turbine on the starting torque under the initial low range of rotational speed. The simulation results show that the starting torque of Darrieus wind turbine varies considerably depending on the blade configuration. The initial starting torque was larger with Troposkien, Parabola, Catenary, and Sandia configurations than with modified parabola or straight types. The increase in solidity with increasing number of blades raised the starting torque and improved the dynamic stability during the initial operational speed of Darrieus wind turbine. Additionally, these torque results represent basic data for fluid-structure interaction (FSI) simulation of the steady-dynamic operation of the turbine.

Solar fed BLDC motor drive for mixer grinder using a boost converter

<p>The existing mixer grinder comprises of the universal motor operating in alternating current supply due to high starting torque characteristics and simple controlling of the speed. The absence of brushes and the reduction of noise in the Brushless DC (BLDC) extends its lifetime and makes it ideal in a mixer grinder. A novel solar-powered BLDC motor drive for mixer grinder is presented in this paper. A DC-DC boost converter has been utilised to operate a PV (photovoltaic) array at its highest power. The proposed hysteresis current control BLDC system has been developed in the MATLAB. A performance comparison is made using the commercially available mixer grinder along with the simulated proposed system.</p>

Design and Analysis of an IE4 Class Line-Start Synchronous Reluctance Motor Considering Total Loss and Starting Performance

In this paper, an optimum design for a three-phase line-start synchronous reluctance motor (LS-SynRM) with respect to efficiency, maximum torque, and starting torque is proposed. The design variables, objective functions, and constraints are selected for this optimum design, which is divided into two steps. Step I maximizes the rated efficiency, while maintaining balanced operation and minimizing the stator copper loss. Step II calculates the precise starting torque using finite element analysis (FEA). The validity of the optimum design is verified by comparing the efficiency, maximum torque, and starting torque characteristics of the time-step FEA with experimental results.

Review on Savonius Rotor for Harnessing Wind Energy

Wind machines convert kinetic energy of the wind into usable form of mechanical energy or electrical energy. The Savonius rotor is a vertical axis wind machine which is simple in design. High starting torque characteristics make it suitable for standalone power generation as well as water pumping applications. This paper reviews the literature on the performance characteristics of the Savonius rotor. Multi-bladed rotor, multistage rotor, shape of the blade, use of deflecting plate, guide vanes and nozzle augmentation are several ways to enhance the performance characteristics. This review would help an engineer in building an improved Savonius rotor for a given application.

Optimum Design of a Single-Phase Line-Start PM Motor Considering Efficiency, Maximum Torque, and Starting Torque

In this paper, an optimum design for a single-phase line start permanent magnet (LSPM) motor with respect to efficiency, maximum torque, and starting torque is proposed. The design variables, objective functions, and constraints are selected for this optimum design, which is divided into three steps. Step I maximizes the rated efficiency while maintaining a balanced operation and minimizing the stator copper loss. Step II utilizes equivalent circuit analysis to consider the efficiency and the maximum torque, while Step III calculates the precise starting torque using finite element (FE) analysis. The validity of the optimum design is verified by comparing the efficiency, maximum torque, and starting torque characteristics of the time-step FE analysis with experimental results.

Design of high performance line start permanent magnet synchronous motor with high inertia load

This paper presents the study of a high performance 3-Phase 3.7kW 2-Pole line start permanent magnet synchronous motor for pumping system. A method was proposed to study the starting torque characteristics considering line start wit h high inertia load. A direct-quadrate model including cage was built to study the synchronization capability. Two-dimensional transient finite element analysis was utilized for accurate calculation of efficiency, starting current speed curve and etc. Structural analysis was also conducted to study the equivalent stress displacement of rotor at rated speed.

Prediction of Starting Torque Characteristics of Epitrochoid Generated Orbital Rotary Piston Hydraulic Motors.

In the present work a theoretical method has been proposed to predict the starting torque characteristics of constant difference epitrochoid generated orbital rotary piston hydraulic motors.For the analysis of such class of Low Speed High Torque(LSHT)hydraulic motors, design and manufacturing data of a few variety of products have been used in the computer calculations to estimate the variation of torque with shaft position over a power cycle.Effects of various factors such as fitting of the rotor-stator (i.e., star-ring), drives, interchamber leakage and their variations with shaft positions have been considered.Finally experiments have been conducted to establish the theoretical model.Experimental result have good agreement with theoretical predictions.

Asynchronous Characteristics of Reluctance Motor with No Rotor Winding

Steady state characteristics of a reluctance motor with no rotor winding, such as VR stepping motor, are the same as those of a conventional reluctance motor, but asynchronous characteristics of it are different from those of conventional reluctance motor.In this paper, asynchronous characteristics of a reluctance motor with no rotor winding are discussed. Equations for calculation of average torque and alternating torque are derived using motor constants. Based on these equations, starting torque characteristics and alternating torque characteristics are investigated.Further, the speed-torque characteristics in asynchronous operation are discussed.The maximum torque, the slip at the maximum torque and the relations among motor constants for having drooping speed-torque characteristics are investigated.In the manner described above, technical data for the reluctance motor with no rotor winding are obtained which are useful for the applications and design of such reluctance motors.

Abnormal starting torque characteristics of a capacitor motor

Abnormal starting torque characteristics of a capacitor motor

Starting Torque Characteristics of Small Aircraft Gas Turbines and APU’s

Starting torque characteristics of small self-sufficient gas turbine engines often present a belated problem to the development engineer, particularly when proceeding into final engine qualification testing over the required range of operational environments. A common procedure is therefore to conservatively over-design the start system with consequent penalties in weight, cost, and size. The various aspects of engine starting are discussed and it is shown that the dominant factor controlling start characteristics at sub-zero ambient temperatures is lubricant viscous shear effects. The magnitude of this effect is such that stored energy start system weights for rapid starting of small aircraft auxiliary power units may weigh as much as the power unit itself. The same auxiliary power units, if used as starters for larger main propulsion gas turbines, are burdened with the incompatibility of torque output dependent upon air density, yet main engine cranking torque is dependent basically upon lubricant viscosity. It is concluded that start system over-design philosophy will tend to persist pending the application of external starting torque directly to the high speed shaft itself with uncoupling of all but necessary viscous parastic shear sources, or until such time as detailed research and development is devoted in applied tribology to further reduce viscous shear effects in high speed turbo-machinery.