Front-End Circuits of Power Line Communication for the Application of Intelligent Electric Power Control Systems in Energy Saving Houses

• Main Authors: Hsiang-En Huang, 黃祥恩
• Other Authors: 楊清淵
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/58844074886375328670

碩士 === 國立中興大學 === 電機工程學系所 === 99 === In the thesis, a front-end interface circuit is proposed, which use power line as data transmission medium. The front-end circuit can provide power line channel noise suppression, signal amplification, and isolating the 110 volts from receiver and transmitter. Combine with the microprocessor, and programmable gate array of the electric equipment to the central monitoring system, as a two-way data transmission link for control signals. The circuit architecture includes a coupling interface circuit, automatic gain controller, and power amplifier. Interface coupled circuit provide high voltage isolation, combined with power amplifier to form active filters, high frequency noise on power line can be greatly suppressed. Power amplifier is implemented with 0.35- um CMOS for a rail to rail Class-AB architecture, the use of the dual complementary differential amplifiers of input stage, and auxiliary transconductance amplifier, providing a full range of width of the input and good driving capabilities. The automatic gain controller is implemented with 0.18 um CMOS, which amplified the signal from power line at receiver. Because during the transmission process, signal will be interfered by noise and caused decadence by transmission path, so receiver can not read properly. Through automatic gain controller, different signal amplitudes can be amplified to the standard level with its gain turning range from -51.4dB ~ 64.2 dB, while the circuit is implemented with 0.18-um CMOS. Finally, consider the structure of a self-oscillation power amplifier, for power line driver. Self-oscillation power amplifier is the improved Class-D power amplifier. The conventional Class-D switching power amplifier is vulnerable to distortion constraints. Due to the non-linear continuous time nature of the self-oscillation, it possesses peculiar properties that enable the construction of a highly linear, high efficiency line driver. In the thesis which has efficiency up to 53%, SFDR and THD are 53.6 dB and 52.8 dB respectively. A prototype has been fabricated in a 0.35-um CMOS process to demonstrate the proposed circuit.