Kuew Wai Chew

Studies of regenerative braking in electric vehicle

Generally the braking system for a car is based on hydraulic braking technology. However, this traditional braking methodology causes a lot of energy wastage since it produces unwanted heat during braking. Thus, the invention of regenerative braking in electric car has overcome these disadvantages moreover it helps in save energy and provides higher efficiency for a car. In regenerative mode, the motor act as a generator, it transfers the kinetic to electrical energy to restore the batteries or capacitors. Meanwhile, the brake controller monitors the speed of the wheels and calculates the torque required plus the excessive energy from the rotational force that can be converted into electricity and fed back into the batteries during regenerative mode. The merits of regenerative braking over traditional braking are energy conservation, wear reduction, fuel consumption and more efficient in braking. Nowadays, the brilliant technology in automotive industry towards regenerative braking is improving. By using a flywheel and ultracapacitor with DC-DC converter it had enhance the regenerative performance. In this paper, the working principle and braking controller for the regenerative braking have been studied to promote the efficiency and realization of energy saving in the electric vehicle.

Infrared and Conductivity Studies on Blends of PMMA/PEO Based Polymer Electrolytes

AbstractPoly(methylmetacrylate)/poly(ethylene oxide) (PMMA/PEO) based polymer electrolytes were synthesized using the solution cast technique. Four systems of PMMA/PEO blends based polymer electrolytes films were investigated:(1)PMMA/PEO system,(2)PMMA/PEO + ethylene carbonate (EC) system,(3)PMMA/PEO + lithium hexafluorophosphate (LiPF6) system and(4)PMMA/PEO + EC + LiPF6 system. The polymer electrolytes films were characterized by Impedance Spectroscopy and Fourier Transform Infrared Spectroscopy (FTIR). The FTIR spectra show the complexation occurring between the polymers, plasticizer and lithium salt. The FTIR results give further insight in the conductivity enhancement of PMMA/PEO blends based polymer electrolytes.

Ultra fast charging system on lithium ion battery

Even with the advancement of the high technology nowadays, the popularity of electric vehicle is still limited and unable to make it a common usage. The main reason is due to the limitation of the battery pack which is bulky, heavy, slow charging, short lifespan and toxicity hazardous. Among these problems, slow charging speed becomes the main consideration when purchasing an electric vehicle. Hence, different charging methods have to be studied thoroughly to seek for the best solution to overcome these problems. In todays competitive battery charging method, a lot of charger manufacturers claim that they can amazingly short charge times of 30 minutes or less. In this project, different charging method such as Constant Voltage charging, Constant Current charging, Pulsed charge etc, have been studied and compared to optimize the charging time suitable for different kind of battery pack.

Chemical and heat resistance of silicone‐acrylic‐based binder and paint system on mild steel panels

Purpose – This paper sets out to study the characteristics of silicone‐acrylic‐based resin and paint systems on mild steel panel for chemical resistance and high‐temperature applications.Design/methodology/approach – Silicone resin has been incorporated into acrylic resin at various compositions. The mixed resins binders and paint systems have been characterised using physical test, acceleration test, electrochemical test and microstructure observation.Findings – The addition of silicone resin into acrylic resin showed significant improvement against high temperature. The results showed that coating film containing at least 30 per cent of silicone resin by weight was able to withstand high temperature of at least 250°C. With the addition of titanium dioxide (TiO2) pigment into the best performing silicone‐acrylic‐based resin system, the system with pigment volume concentration of 30 per cent TiO2 showed the best performance which indicated the value of critical pigment volume concentration. The finding sh...

Characterizations of Silicone – Acrylic Based Resin/Paint Coatings on Mild Steel Panels

The properties of silicone-acrylic based resin have been characterized. Different portions of silicone resin ranging from 10% to 60% have been added into acrylic resin. The mixed resins were then applied on mild steel panels by brushing method. The coated panels are allowed to dry under ambient condition for 7 days before being characterized by electrochemical impedance spectroscopy (EIS), Scanning electron microscopy (SEM), mechanical test and potential-time measurements technique (PTM). The composition with at least 30% silicone content showed the best performance. By selecting the best silicone-acrylic composition (30% Silicone resin and 70% acrylic resin) resin have been selected to made paint. A series of paint consist of silicone-acrylic resin were designated with pigment volume concentration (PVC) ranging form 10 to 60% using titanium dioxide pigment. The thicknesses of the tested coatings were similar. By utilizing the same test methods, results showed that the coatings with approached to critical pigment volume concentration (CPVC) showed the best performance against high temperature and corrosion attacks.

Studies on the properties of silicone resin films on mild steel

The physical properties of two types of silicone resin were examined. The resin was coated on mild steel panels and allowed to cure for one week. The resin‐coated panels were heated according to ASTM specification D 2485. The thermal stability of the resin coatings was examined by electrochemical impedance spectroscopy (EIS) technique and thermogravimetric analyses (TGA). The chemical resistance property of the resin coatings was also studied.

Contour Data Acquisition System for Electric Vehicle Distance Estimation Method

The conventional distance estimation system only uses a constant speed and a constant level of road elevation to estimate the driving mileage for a vehicle. This technique leads to a low accuracy. In the current project, a new estimation technique namely; the Contour Positioning System (CPS) for an electric vehicle has been proposed. The CPS has a better estimation on the electric vehicle battery usage because of the consideration of road elevation, regenerative energy etc. In order to perform the CPS calculation, the elevation profile of the selected destination must be known. In this paper, the technique to extract the elevation profile i.e. latitude, longitude and altitude has been performed and evaluated using Google Maps or Google EarthÒ. This method enables the user to obtain the road information and compute the amount of energy needed to reach the said destination.

Contour Positioning System - New Traveling Distance Estimation Method for Electric Vehicle

Contour Positioning System (CPS) is a new system invented for electric vehicles to calculate the remaining battery capacity for reaching a desired destination. Instead of using conventional electric car estimation in terms of distance, a CPS system can figure out extra energy needed when an electric car is traveling on different contour lines. Extra current will be drawn for generating torque required by the electric car on an inclined plane, for instance traveling uphill. By using coordinate conversion, sets of longitude and latitude readings can be converted into distance difference along the pathway and the elevation levels difference are calculated; the extra force and torque needed along an inclined plane can be further counted which will then lead to the extra current drawn from the electric cars battery pack. Data collections and real-time validations have been done to clarify the calculation results. By performing a series of battery capacity calculation, CPS can give a higher precision and accuracy of remaining battery life to reach the desired location

System setup consideration for range gated imaging

Despite the advances made in laser and sensor technology, setting up an accurate range gated imaging system remains a challenge. In this paper, we emphasise on the importance of system setup and its impacts to the performance of three-dimensional (3D) range gated reconstruction. Study is performed to analyse some of the system setup criteria and parameters involved in the laser and camera synchronisation, images acquisition and reconstruction, and illumination setup. It is hoped that the presented findings establish better understanding of the setup influences in range gated reconstruction and contribute to optimise the system performance.

Investigation on compressed wavefront sensing in freeform surface measurements

In this paper, conventional modal wavefront reconstruction is compared with compressed wavefront sensing to reconstruct freeform surface profiles using the Shack-Hartmann wavefront sensor. The modal wavefront reconstruction represents the phase or the wavefront in the Zernike domain. The compressed wavefront sensing method based on the sparse Zernike representation (SPARZER) represents the phase slopes in the Zernike domain. The effectiveness of compressed wavefront sensing in freeform surface profile measurements is investigated.