A Comparative Study of Sensor and Sensor less Control of Four-Switch Inverter Fed Permanent Magnet Brushless DC Motor

Abstract –

Permanent Magnet Brushless DC (PMBLDC) machines are more popular due to its simple structure and low cost.  Improvements in permanent magnetic materials and power electronic devices have resulted in reliable, cost effective PMBLDC drives, for many applications. PMBL motors find applications in diverse fields such as domestic appliances and automobiles due to its low cost and performance. Modelling, simulation and experimentation of drives with new converter configuration and control schemes are essential for making this drive competitive. In this paper, a comparative study between sensor and sensor less control of four-switch Inverter fed PMBLDC is discussed and Simulation model using transfer function of BLDC motor is presented. Hardware implementation is done with DSP processor TMS 320LF2407.

A Series-Connected Three-Level Inverter Topology for Medium-Voltage Squirrel-Cage Motor Drive Applications

Abstract—

The application of pulsewidth-modulated (PWM) voltages using two-level high-voltage inverters to a squirrel-cage induction motor (SQIM) can cause heating of rotor shaft, voltage spike across the motor terminals, etc. The increase in the number of steps of the motor voltage and hence decreasing the dv/dt applied to the machine terminals can be a solution to this problem. The existing topologies that generate this multistep voltage include cascading of a number of single-phase inverters or use of higher order multilevel inverters. In this paper, a topology with series connection of three-phase three-level inverters is proposed, which addresses the problems of medium-voltage drives. The design of the inverter topology and its various PWM techniques are presented in this paper. This inverter topology and its control are verified on a 7.5-hp SQIM drive. Experimental results validate the steady-state and dynamic performances of the drive.

Dynamic Model for a Chopper-Controlled Slip-Ring Induction Motor

Abstract-

A thyristor-controlled chopper circuit is used on the rotor side for speed control of a slip-ring induction motor drive. A small signal dynamic model is developed for this particular drive which can be used for studying closed-loop drive performance. Theoretically obtained results are compared with those obtained experimentally.

Study of Slip Energy Recovery of Induction Motor Drive Using Matlab/SimuIink

Abstract:

Induction motor drive, considering its significantly indua trial applications, has great importance. Squirrel cage IM are generally controlled by varying voltage and frequency fed to the motor. For high power drive, because of use of forced commutations converters. squirrel cage IM have less application. In this case and particularly when load torque is proportional io high order of speed, wound rotor Ihl is used. In these motors speed is controlled by energy absorption from rotor and returning it to network. Return of slip energy to network improve efficiency. but Small power factor and harmonic injection rest as P predominant problem in this drive system. In Ihis paper slip energy recovery method will be studied by dvnamic modeling. To study Slip energy recovery system and effect or the method on Harmonics, power factor, lorque-sperd characteristic and overall performance oldrive, a block set is implanted in Matlab/Simulink environment.

A Switched-Capacitor DC–DC Converter With High Voltage Gain and Reduced Component Rating and Count

Abstract—

This paper proposes a bidirectional switched-capacitor dc–dc converter for applications that require high voltage gain. Some of conventional switched-capacitor dc–dc converters have diverse voltage or current stresses for the switching devices in the circuit, not suitable for modular configuration or for high efficiency demand; some suffer from relatively high power loss or large device count for high voltage gain, even if the device voltage stress could be low. By contrast, the proposed dc–dc converter features low component (switching device and capacitor) power rating, small switching device count, and low output capacitance requirement. In addition to its low current stress, the combination of two short symmetric paths of charge pumps further lowers power loss. Therefore, a small and light converter with high voltage gain and high efficiency can be achieved. Simulation and experimental results of a 450-W prototype with a voltage conversion ratio of six validate the principle and features of this topology.

Simple Power Control for Sensorless Induction Motor Drives Fed by a Matrix Converter

Abstract—

This paper presents a new and simple method for sensorless control of matrix converter drives using a power flowing to the motor. The proposed control algorithm is based on controlling the instantaneous real and imaginary powers into the induction motor. To improve low-speed sensorless performance, the nonlinearities of a matrix converter drive such as commutation delays, turn-ON and turn-OFF times of switching devices, and ON-state switching device voltage drop are modeled using a PQ power transformation and compensated using a reference power control scheme. The proposed sensorless control method is applied for the induction motor drive using a 3 kW matrix converter system. Experimental results are shown to illustrate the feasibility of the proposed strategy.

THD Reduction in Performance of Multi-Level Inverter fed Induction Motor Drive

Abstract—

Multi-level voltage source inverters offer several advantages such as a better output voltage with reduced total harmonic distortion (THD), reduction of voltage ratings of the power semiconductor switching devices and also the reduced electro-magnetic interference problems etc. This paper presents the application of simplified space vector modulation (SVM) method for three-level, five-level and seven-level diode clamped inverters feeding a three-phase Induction motor. The space vector diagram of the multi-level inverter is decomposed into six space vector diagrams of two-level inverters. This paper compares total harmonic distortion values of voltage and current waveforms of Induction motor to the conventional two-level inverter drive using diode clamped multi-level inverter (Three, five and seven level).