KMITL

Permanent URI for this communityhttps://dspace.kmitl.ac.th/handle/123456789/1

Browse

Search Results

Now showing 1 - 7 of 7

Some of the metrics are blocked by your
consent settings
Comparison of starting current characteristics for three-phase induction motor due to phase-control soft starter and asynchronous PWM AC chopper
(2017-05-01)
Thanyaphirak, Veera
;
Kinnares, Vijit
;
Kunakorn, Anantawat
This paper presents the comparison of starting current characteristics of a three-phase induction motor fed by two types of soft starters. The first soft starter under investigation is a conventional AC voltage controller on the basis of a phase-control technique. The other is the proposed asynchronous PWM AC chopper which is developed from the conventional synchronous PWM AC chopper. In this paper, the proposed asynchronous PWM AC chopper control scheme is developed by generating only two asynchronous PWM signals for a three-phase main power circuit (6 switching devices) from a single voltage control signal which is compared with a single sawtooth carrier signal. By this approach, the PWM signals are independent and easy to implement since the PWM signals do not need to be synchronized with a three-phase voltage source. Details of both soft starters are discussed. The experimental and simulation results of the starting currents are shown. It is found that the asynchronous PWM AC chopper efficiently works as a suitable soft starter for the three-phase induction motor due to that the starting currents are reduced and are sinusoidal with less harmonic contents, when being compared with the starting current waveforms using the conventional phase-control starting technique. Also the proposed soft starter offers low starting electromagnetic torque pulsation.
Some of the metrics are blocked by your
consent settings
Electrical modeling and simulation of industrial power system with Matlab/Simulink program
(2013-07-12)
Aree, Pichai
;
Nakawiro, Worawat
Power system dynamic simulations have been traditionally constrained to commercial package tools. While these tools are mostly efficient for large scale simulation, their component models are often encapsulated, and not possible to be examined and modified. For educational use, it is more important that the component modeling is transparent and flexible. Hence, in this paper, an object-oriented simulation of an industrial power system is constructed in Matlab/Simulink environment. The step-by-step implementation of Simulink block diagram model describing power system devices is fully given in detail. This presented approach is well suited to educational purpose in a way that students are able to modify their models and get quick start their simulations. The dynamic simulations with result and discussion are given through illustrative case study of voltage sag.
Some of the metrics are blocked by your
consent settings
Induction motor speed measurement using motor current signature analysis technique
(2009-12-01)
Phumiphak, P.
;
Chat-uthai, C.
As the procedure of nonintrusive method for field efficiency estimation of induction motor requires the actual motor speed from direct measurement by using shaft-mounted speed encoder or optical tachometer which reduces the reliability and also increases the cost. In this paper, the sensorless speed measurement scheme using implementation of motor current signature analysis (MCSA) is proposed. Both line-fed (sinusoidal) and inverter-fed (nonsinusoidal) motors with different operating frequencies are considered. In this technique, neither equivalent circuit parameters nor structures of machine are required. Moreover for inverterfed motor, the information of inverter such as switching frequency and switching PWM scheme are not required. This proposed technique is verified from the experimental results of measured speeds of 2.2 and 4.0 kW three-phase induction motors operated under various load torques. The experimental results show that the overall speed estimation accuracy is approximately within 2 rpm errors.
Some of the metrics are blocked by your
consent settings
Stator faults detection based on the dq0 voltage components
(2008-10-30)
Manop, Chalermchat
;
Kinnares, Vijit
This paper presents the technique for detection of shorted turns in stator winding of induction motors. The strategy is based on the dq0 voltage components. The proposed technique determines dq components of time domain of harmonics obtained from Park transformation instead of the stator phase voltage. Zero component (0) is calculated from the fundamental voltage excitation only. In the testing, the supply is sinusoidal waveform and the motor must be star connected with floating neutral. From experimental results, pattern of dq0 voltage components in order to use for the stator faults detection is possible. ©2008 IEEE.
Some of the metrics are blocked by your
consent settings
A low cost prototype for testing stator winding shorted turns in 3-phase induction motors
(2005-12-01)
Manop, Chalermchat
;
Senavongse, Wongwit
;
Kinnares, Vijit
;
Tangsiriworakul, Chanwit
This paper presents a prototype of stator winding shorted turns detector for three-phase induction motors. The focus condition is turn-to-turn short circuit, because this condition is the initial problem. The diagnosis technique is detectable from the voltage sum of the three instantaneous line to star-point voltage. In the testing, the supply is sinusoidal waveform and the motor must be star connected with floating neutral. Before diagnosis, this instrument will also determine the level of supply voltage imbalance, if it is over the limit, the test instrument will not diagnose shorted turns. From experimental results, 3-hp and 5-hp induction motors were used for testing this equipment which is capable of accurately identifying percentage of stator winding shorted turns. © 2005 IEEE.
Some of the metrics are blocked by your
consent settings
Acceleration test for small three-phase integral horsepower induction motors-techniques, limitation, and problems of the test and interpretation of the results
(2003-01-01)
Sae-Kok, W.
;
Lumyong, P.
This paper aims at the realization of the acceleration method for the small three-phase integral horsepower induction motors as referred to IEEE standard 112-1996. Testing on the small induction motors with an increasing moment of inertia technique is proposed. The characteristic results, the current-speed and torque-speed characteristics, are presented. In addition, verification of the results, limitation, and problems of this method are also interpreted. The limitation of this method is illustrated by loss calculation performed by comparing with current data from the locked-rotor test at rated voltage. This paper presents the method to find the appropriate time for the acceleration test. Finally, the problem which presents during the test is also discussed.
Some of the metrics are blocked by your
consent settings
Speed control of three-phase induction motor online tuning by genetic algorithm
(2003-01-01)
Chiewchitboon, P.
;
Tipsuwanporn, V.
;
Soonthornphisaj, N.
;
Piyarat, W.
This paper presents the technique of three phase induction motor controls by using the genetic algorithm. The genetic algorithm is control by a PC and PWM is generated by MCS-51, the gain K<inf>P</inf>, K<inf>i</inf> which will be selected by genetic algorithm controller to sense and select the adequate load. The genetic algorithm technique can control the suitable amount supplying power to motor speed by variable input frequency feed to the motor. The controller is implemented to the real time application by creating the controller box that signal is linked to the PC via the RS232 port. The result are shows that the good performance compared with PI controller that gain K<inf>P</inf>, K<inf>i</inf> are manual inputs. This real time application will support the development in industrial.

KMITL

Browse

Filters

Settings

Sort By

Results per page

Search Results