Papers by Keyword: Soft-Start

Abstract: The "soft start" problem was studied for magnetic coupling in coal mine by experimental method. At first, the starting condition of magnetic coupling was analysed. Aaccording to the load characteristics of conveyor. Secondly, the torque characteristic curve, speed characteristic curve and current starting curve were plotted using the experimental data. From three kinds of characteristic curve we have conclusion that the output torque and output speed is much less than the input torque and input speed, the starting current value with the load was less than the starting current value when directly connected. That means magnetic coupling with the soft start characteristic.

Abstract: Through the research on the structure and properties of different soft start device applied to long distance and large capacity belt conveyor. Analysis and comparison of technical characteristics of some used soft start of this kind of belt conveyor, and then get the reasonable way of soft start. In order to provide optimization scheme of application of belt conveyor in long distance and large capacity in the actual production for enterprise.

Abstract: Rural grid has large waste for its discontinuity in application. Li-ion battery, with feature such as small size, large power density, high single voltage, low self-discharge rate, low inner resistor and so on, has been applied in power storage system. The intelligent power storage system based on li-ion battery and super capacitor can effectively storage the extra power in the period of grid off-peak, and also could absorb the feedback energy when the velocity modulation system is braking, largely increases the use rate of energy storage.

Abstract: Automated Mechanical Transmission (AMT) is applied as a new starting device for belt conveyor in the paper. Simulation model of AMT driving belt conveyor is established in AMESim. Simulations of start-up process at first gear condition and shifting process from first to eighth gear are discussed. Belt velocity is accepted as the law of gearshifts to judge the moment of shifting. Simulation results show that AMT could achieve the purpose of belt conveyor’s soft-starting gradually. The belt appears short-time acceleration mutations during shifting process which results in the belt maximum tension, the driving pulley torque, and other parameters changing within their allowable limits. The belt maximum tension appears short-time mutations when the clutch is just engaged, in which case the peak value of belt maximum tension can achieve 110 KN approximately, and is less than its allowable limit. After shift actions, the belt maximum tension and other parameters curves tend to be stable.

Abstract: This paper introduces several methods of soft start of belt conveyor, Through the analysis of all kinds of soft start mode, the prospects of development of soft start device of belt conveyor, and through the comparison of several commonly used start speed curve, the reasonable start speed curve, pointed out the direction for the research of soft start device of belt conveyor.

Abstract: Aimed at the high starting current, low power factor and low running efficiency, a novel soft starter with current-limiting, reactive power compensation and harmonic filtering is developed in this paper. The following works have been done in the study: the research of topological structure, the design of hardware and software of the control system, the validation of experimental result. It has been successfully applied to the fans load of 10kV, 19000kW, and got better effects, and satisfies the characteristics of the current-limiting and reactive compensation during this motor starting. It can also realize the power harmonic filtering after the motor soft starting, improve the whole starting performance, save energy and keep the grid voltage stable, with easy engineering implementation and high cost performance.

Abstract: The boot method of three wound-rotor asynchronous motors and three-phase squirrel-cage asynchronous motor are described; As to reduce the start current and to increase the starting torque, the principle of all kinds of startup methods are analyzed; the advantages and disadvantages of various starting methods are evaluated; Development directions of modern motor startup are pointed out.

Abstract: For soft-start system of for belt conveyor with long-distance and high-power, this essay, combining with lots of mechatronics research, design, application and commissioning work related with belt conveyor, researched and analyzed structure and governor principle of soft-start devices or systems successfully applied in coal mines or other industries. Furthermore, it evaluated each type of soft-starters in technical and economic aspects, which will play a guiding role in reasonable selection and application of soft starting devices.

Abstract: Reliable soft-start system is crucial to smooth and safe operation of belt conveyor. Therefore, based on analysis of behaviors of the three-phase asynchronous motors’ reduced voltage starting and ordinary hydraulic coupling independently applied to the conveyor belt, this essay proposes an original method of regulating voltage soft-start, introduces the principle and process of soft start, and determines strategies on power balance among several motors.

Abstract: This paper analysis the control principle of the asynchronous motor soft-start with discrete variable frequency technology．A simulation model for the asynchronous motor soft-starter using discrete variable frequency technology is built based on MATLAB SIMULINK/POWER SYSTEM．In start process, positive sequence sub - frequency such as 13、10、7、4 discrete variable frequency is used in the soft-starter to simplified power circuit and its control. While on the power frequency time slice ,a single neuron PID algorithm is used to limit the current. The simulation results verify the asynchronous motor soft-starter with discrete variable frequency technology not only reduces the initial firing current but also has bigger start torque, which has a faster start speed compared with the normal soft starter with current limit starting control technology.