Conventional Method And Space Vector Pulse Width Modulation Technique For Ripple Reduction

TM4, the industrial partner, is a leading manufacturer and supplier of traction motors and drives for electric vehicle industry in Canada. As a drive manufacturer, they always aim to provide solution which is energy efficient with small footprint. In order to achieve this, they always look for alternative software and hardware solutions. Software modifications, which may improve the system performance in comparison to their existing drive control strategy without increasing the size of the system, are always sought after for continuous improvement of their system. In this regards, the internship is relevant to them for exploring alternative control strategies.

The impact of the proposed sequences has been simulated for 0.4 modulation index with a 0.5 lagging power factor load (power factor angle 60°). The simulation setup consists of the following software: 1) MATLAB/Simulink – used to implement the modulation strategies and switching sequences, and 2) PSIM – used to simulate the T-NPC inverter running with an R-L load and to provide conduction and switching losses of each switch. The inverter switching pulses were generated within Simulink and were fed to PSIM through sim-coupler module which provides a link between PSIM and simulink for the purpose of co-simulation [29].

The three phase induction motor is considered the mostly used electrical motor in all the industrial applications. The three phase induction motors are considered good because of their simplicity, rigidity, cheapness, easily maintained and could be made up with features that are suitable for most industrial requirements.

Economically, petroleum fuel prices have escalated in the past, which make the use of the electrical controlled vehicle a great alternative to manage the cost issues. Therefore, this research proposal focuses on Electrical Vehicle technology.

The advantages of Field Oriented Control are transformation of a complex and coupled AC model into a simple linear system , independent control of torque and flux, fast dynamic response , good transient and steady state performance ,high torque and low current at start up and high Efficiency[2].

Single loop control methods allowed a single voltage control loop to regulate the output voltage. The input current shaping is accomplished in an open loop manner, the duty cycle patterns are predefined by considering in ideal PFC operation. One example in this control method is the duty phase control (DPC) proposed by Chen [42]. In this method, a phase shift is willingly introduced to the stored duty cycle patterns. The output voltage is regulated by adjusting this phase shift by using the output of the voltage error amplifier, which is named “the duty phase”. This approach simplified the control structure and eliminated the current loop, without the need to

1) are derived first by algebraically solving the equivalent circuit shown in Fig. 2. These extreme values include maximum torque, maximum mechanical power, maximum power factor, maximum efficiency, and maximum electric power. It will be shown that the torque and mechanical power extrema can be expressed in analytical forms while the power factor, efficiency and electric power extrema need to be solved numerically. It will then be shown that these extrema can also be determined graphically using the circle diagram method. The circle diagram method is an old method but can still be found in some textbooks (e.g., [3]-[4]). The research into graphical methods for induction motor analysis is still active (e.g., [5][11]). One may consider that the circle diagram method is limited to qualitative evaluation because it cannot give accurate results. In fact, if the circle diagram method is carried out by a modern computer drawing tool that allows the user to draw geometric diagrams with parameters (i.e., coordinates, lengths, angles, etc.) to the accuracy of four decimal places, then the circle diagram method is able to give all the aforementioned performance extrema with required accuracy. Unlike the circle diagram method used in [10] and [11] that is based on the approximate equivalent circuit of induction machine and is limited to motoring mode of operation, the circle diagram method used in this paper is based on

Power electronic converters, especially DC/AC inverters have been extending their range of use in industrial application because they provide better system efficiency, reduced energy consumption and improved quality of power. The output voltage of inverter could be fixed or variable at a fixed or variable frequency and output waveforms are therefore made up of discrete values, producing fast transition rather than smooth ones [2]. The ability to

This new technology has replaced many of the old ones, bringing many advantages to the user, for example DC & AC drives, soft stators, UPS, etc. Since this new technology is rapidly gaining in the modern industries, power systems are expected to provide an ideal sinusoidal waveforms for currents and voltages,

Brushless DC motors is a kind of permanent magnate synchronous motor. Permanent magnet synchronous motors are classified on the basis of the wave shape of their induce emf, i.e, sinusoidal and trapezoidal. The sinusoidal type is known as permanent magnet synchronous motor (PMSM); the trapezoidal type goes under the name of PM Brushless dc (BLDC) machine. Table (2.1) shows the difference between (PMSM) and (BLDC) motor.

Brushless direct current (BLDC) motors are preferred as small horsepower control motors because their efficiency is very high, the operation is in a silent mode, has a compact form, contains high precision, low maintenance, Its structure is simple, and has a large torque, etc. Hence, it is extensively used in national defense, aerospace, robotics, industrial process control, precision machine tools, automotive electronics, household appliances and office automation [1].

Brushless direct current (BLDC) motors are preferred as small horsepower control motors because their efficiency is very high, the operation is in a silent mode, has a compact form, contains high precision, low maintenance, its structure is simple, and has a large torque, etc. Hence, it is extensively used in national defense, aerospace, robotics, industrial process control, precision machine tools, automotive electronics, household appliances and office automation [1].

This paper investigates adjustable speed induction motor drive using 2-level and 3-level PWM.The result obtained is verified using Matlab simulation.This result compares the hamonic contect in between 2-level and 3-level by FFT analysis tool.To analyse the resulta a carrier based pwm was taken using 2- level and 3- level topology and a threephase bridge convetor with internally generated capability SPWM/SVPWM was intrduced. Carrier freqency18*60Hz, modulation index 0.9, output voltage freqency 60 Hz and ouput voltage phase 0 degre Was fixed. So corresponing to above values,the motor speed was 1800 rpm. Or 188.5 radian/sec, hence torque is 11.87Nm. A two pole squirrel cage motor was taken subjected to 400V dc source with modulation index0.9 prduces 220v rms.when motor starts, at 0.5s it reaches its steady speed 181 radian/sec or 1728 rpm. Now by discretizing the FFT tool displays the frequency spectrum of voltage and current waveforms. These signals are stored in workspace in the ASM structure with time variable generated by the Scope block. As my model is discretized, the signal saved in this structure is sampled at a fixed step and consequently satisfies the FFT tool requirements.It was observed that value of total harmonic distortion(THD) was 65.77 percent in 2-level and 35.11 percent in 3- level for SPWM invertor and 56.77 percent for SVPWM invertor.

Power electronic converters, especially DC/AC inverters have been extending their range of use in industrial application because they provide better system efficiency, reduced energy consumption and improved quality of power. The output voltage of inverter could be fixed or variable at a fixed or variable frequency and output waveforms are therefore made up of discrete values, producing fast transition

The brushless DC motors are becoming more popular in low and medium power applications due to the characteristics they have such as better speed versus torque characteristics, high dynamic response, high efficiency, noiseless operation and higher torque to weight ratio. They also have a long life span. With rapid development in power electronics, semiconductor and manufacturing technology for high performance magnetic materials, the brushless DC motors have been used for energy savings applications such as air conditioners, refrigerators, air pumps, kitchen appliances and electric vehicles.