The Key Technology of Complete Protection for the High Voltage Variable Frequency Drive System

In order to study the effect of variable frequency drive system upon electromagnetic radiation environment in underground coal mines, the mechanism of electromagnetic radiation from the variable frequency speed regulation system has been analyzed deeply, and the radiated electromagnetic noise from the variable frequency winch system with rated voltage of 1140V in underground coal mines has been measured. The measuring results show that the radiated emission from variable frequency drive system has certain effects on electromagnetic radiation environment in underground coal mines. The maximum radiated E-field strength reaches 123dBμV/m within the range of 9kHz to 20MHz nearby the frequency converter, and radiated E-field strength is no more than 33dBuV/m above 20MHz. Nearby the winch motor, the radiated E-field strength is weak, but the frequency spectrum of radiated E-field noises is more wide, which mainly distributes from 20MHz to 1GHz, but the maximum radiated E-field strength is less than 37dBμV/m above 20MHz.

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Design ADRC for Cutter Suction Dredger Cutter Motor Variable Frequency Drive System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1008-1009.650 ◽

2014 ◽

Vol 1008-1009 ◽

pp. 650-653 ◽

Cited By ~ 1

Author(s):

Ming Bai ◽

Jin Hua Chen ◽

Cheng Ning Xie ◽

Fang Hui Li

Keyword(s):

Virtual Instrument ◽

Design Method ◽

Harmonic Distortion ◽

Speed Control ◽

Mathematic Model ◽

Drive System ◽

Variable Frequency ◽

Fundamental Wave ◽

Variable Frequency Drive ◽

Labview Platform

In order to achieve precise speed control for cutter suction dredger cutter motor, the controller should adapt well to uncertainties, such as geological environment, water flow, mechanical disturbance, etc. It makes the design of cutter motor controller always a hard work. This paper proposes an active disturbance rejection controller (ADRC) approach for cutter suction dredger cutter motor variable frequency drive system. Firstly, the LabVIEW platform was established by virtual instrument technology, which collected operating data of cutter motor in fundamental wave and total harmonic distortion (THD). Then cutter motor motion mathematic model was built and the ADRC design method was introduced. Lastly, the simulation results in the cutter velocity control and disturbance environments were done. The results show that the ADRC controller has strong robustness, and the precise speed control can be implemented.

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The Influence of Main Pump with High-Voltage Variable Frequency Drives on Electric Motors Periodic Repair

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.698.3 ◽

2014 ◽

Vol 698 ◽

pp. 3-6 ◽

Cited By ~ 3

Author(s):

V.A. Shabanov ◽

M.I. Khakimyanov ◽

E.F. Khakimov

Keyword(s):

Service Life ◽

High Voltage ◽

Residual Life ◽

Variable Frequency ◽

Electric Motors ◽

Start Time ◽

Variable Frequency Drive ◽

Oil Companies ◽

Cyclic Transfer ◽

The Impact

The main objective of the work - to investigate the effect on the wear of high voltage electric motors of main pump units periodic switching on and off in cyclical pumping. Frequent starts motors in a cyclic pumping lead to accelerated wear of the mechanical parts of the motor due to the impact of dynamic loads at start-up, as well as winding insulation due to high inrush currents flow. As a result of accelerated depreciation may decrease residual life, overhaul period and service life of electric motors. The main factor affecting the service life of insulation motors are winding temperature, and as a consequence, the thermal aging of the insulation. The use of variable frequency drive can significantly reduce the cyclic transfer modes, or even eliminate them. The authors obtained analytical expressions for the evaluation of insulation deterioration at the start of the motor, which allow us to study the impact of the following factors: insulation class, the start time, break time at work, initial and nominal temperature, the temperature rise of the windings over the ambient temperature. The effect on the deterioration of the insulation cold start and hot conditions, as well as the percentage of the hottest start-ups in the total number of starts. Obtained expressions for the depreciation of isolation to determine the change timing of overhauls of high voltage electric main pump units. The developed method was approved by the example of the use of a variable frequency drive on the oil pumping stations construction section Leninsk-Nurlino trunk pipeline Nizhnevartovsk - Kurgan - Kuibyshev. The analysis showed that the installation of a variable frequency drive motors on three main pump units technological area of the number of starts to decline by 14%. The results can be used for pipeline transport of oil companies when planning the timing and costs of the current and capital repairs of high voltage electric motors main pump units.

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MATLAB /Simulink Modelings and Experimental Design of Variable Frequency Drive for Speed Control of Three-Phase Induction Motor

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.b3068.078219 ◽

2019 ◽

Vol 8 (2) ◽

pp. 3046-3052

Keyword(s):

Induction Motor ◽

Continuous Process ◽

Speed Control ◽

Drive System ◽

Variable Frequency ◽

Inrush Current ◽

Variable Frequency Drive ◽

Matlab Simulink ◽

Three Phase ◽

Wide Range

This paper presents the PWM (Pulse Width Modulation) based speed control of three-phase asynchronous (Induction) motor. Induction motor is the leading machine used in many industrial controls, automation processes and in the field of HVAC applications. However, induction motor has fixed rated speed when directly connected to ac supply. It is necessary to design a drive system to obtain variable speed at its output to fulfill the application requirement. For this reason, we have designed a “VFD (Variable Frequency Drive)”, which gives desired speed- according to load changes unlike the DC motors, which do not require any speed controlling drive. Currently with the technological elevation in drive systems, the speed control of induction motor is more economical, convenient, reliable, and accurate. It provides continuous process control over a wide range of speed. VFD not only controls the speed of induction motor but also make its starting smooth by reducing starting inrush current and improves power factor. In result, power consumption is also reduced. In this paper, we have designed and analyzed the MATLAB/Simulink model of open loop drive system and then implemented an experimental hardware design.

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