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- Creator:
- Sharma, Menish Kumar
- Description:
- Power transformers in a utility grid are expected to work without failure under a wide variety of circumstances, such as times of power system instability, extreme weather conditions, and electrical faults. Because of the extremely high up-front cost to purchase a transformer and its importance as an asset in the utility grid, it is critical for utilities to perform maintenance to ensure reliability, dependability and determine incipient problems that may lead to potential failure. The focus of this project is to review and develop an online and offline electrical maintenance testing program for a power transformer. This project will analyze the online and offline maintenance tests to trouble shoot a real-world problematic power transformer using various maintenance methods. Engineering analysis on the maintenance data will be performed to create a root cause failure report.
- Resource Type:
- Project
- Campus Tesim:
- Sacramento
- Department:
- Electrical and Electronic Engineering
- Creator:
- Li, Jinqiu
- Description:
- A dynamic service restoration (DSR) method based on load curve variations, is proposed in this project. The application of the time variable load is considered to make an effective service restoration plan for affected distribution systems. Based on the available load curves of Sichuan provincial power system in China, the proposed method identifies the optimal candidate network configurations. The network configuration is altered for each hour over the restoration period. A service restoration plan with global dynamic characteristics is formed. The established distribution systems DSR is a constrained multi-objective mathematical model. Computation complexity is reduced by a two-stage solving methodology. A couple of case studies of a 70-node distribution system are presented in the paper. The simulation results indicate that, the proposed method will provide a fast, secure and reliable service restoration plan of the distribution.
- Resource Type:
- Project
- Campus Tesim:
- Sacramento
- Department:
- Electrical and Electronic Engineering
- Creator:
- Mapinda, David
- Description:
- The quality of power is the major challenging issue in the power system. In real-world power systems, it is ordinarily impossible to maintain perfect balance in phase voltages and currents. The variety of the loads in the networks enhances the amount of unbalance or negative sequence components. In conjunction with asymmetrical load, further increase in negative sequence components is introduced due to the network inherent asymmetry. The power quality is very much affected by the magnitude and phase disturbances of three phase voltage and current respectively. The proposed balancing compensator is built as reactive device uses the shunt current source compensation whose instantaneous values are determined by the instantaneous symmetrical component theory. The compensation configuration developed in this paper is tested for its cogency on 3-phase,3-wire circuit through wide-ranging simulations for phase outages scenarios. The simulation results for the compensation theory and the ideal compensator verify the proposed compensation method. In this paper, a general analysis of control strategy to mitigate negative-sequence and zero sequence currents in unbalanced three-phase power systems is proposed.
- Resource Type:
- Project
- Campus Tesim:
- Sacramento
- Department:
- Electrical and Electronic Engineering
- Creator:
- Shen, Kexian
- Description:
- Stereo vision systems imitate the mechanisms of natural human vision to get threedimension information from captured scenes. It is applied in the control of autonomous robots (to build a map of the environment) and the control of production tools. Stereo systems are deployed to identify objects and can be used for determining close-range depth. However, the error in estimated depth grows quadratically with the real depth. To increase accuracy, we must adjust the focal length and the baseline. Most cameras’ focal lengths are flexible to suit different scenes. However, once the baseline is fixed, it is inconvenient to change. Therefore, finding a suitable baseline is vital when designing a stereo vision system. To find the relationship between baseline and depth accuracy, the accuracy estimation needs to be analyzed based on stereo vision model and error propagation. Meanwhile, a measurement experiment will be conducted to confirm the relationship. The image data used in this project are captured by two GoPro cameras. Camera calibrations, as well as image operations and calculations are conducted using MATLAB. The accuracy of estimation is analyzed, which shows a simple relationship between accuracy and baseline. Based on this relationship, it is easy to determine a suitable baseline for different applications.
- Resource Type:
- Project
- Campus Tesim:
- Sacramento
- Department:
- Electrical and Electronic Engineering
- Creator:
- Bahubali Upadhye, Abhinandan
- Description:
- Electrocardiograph (ECG) recorders are medical devices used to measure and record electrical signals generated by the activity of the heart in the human body. Doctors use the data from an ECG to detect signs of cardiac disease in a patient. The input signal to an ECG recorder is a low-frequency analog signal that is very small in amplitude, on the order of only 1-10mV. So the analog front end (AFE) for an ECG recorder must first amplify this small signal, while adding as little noise as possible. The focus of this project is to design and simulate a low noise amplifier (LNA) for the AFE of an ECG integrated circuit (IC) in a 0.18μm CMOS process. This LNA must achieve a high common-mode rejection ratio (CMRR) to reject ambient noise in the surrounding environment, while providing voltage gain and minimizing the noise that it adds to the signal. The amplifier presented here achieves these goals while also minimizing the amount of power used. The circuit accomplished the preceding by means of a current-balancing technique in its feedback circuit. The performance of this LNA was verified through simulations across process, supply voltage, and temperature (PVT) variations using professional IC design CAD tools.
- Resource Type:
- Project
- Campus Tesim:
- Sacramento
- Department:
- Electrical and Electronic Engineering