Study on New Smart Transformer Terminal Unit Based on ARM and GPRS Network

Abstract

Distribution transformer is one of the mostimportant power equipments in distribution network, whoserunning state exercises a great influence on the stability of thenetwork. Transformer Terminal Unit (TTU) is an effective deviceto monitor the running state of transformers in the distributionautomation system. In this paper, we study a new smart TTUwhich uses ARM7 series chip as processor, equipped withATT7022B based electric meter module and GPRS module forremote data transmission control. We focus on the correspondinghardware, software design and the measurement principle ofharmonics of TTU. The new TTU can measure the electricparameters of the distribution transformer precisely. Takingadvantage of the powerful ARM processor, it can analyzeharmonic of the power line effectively. Due to the always-on-linefeature of GPRS, TTU can achieve reliable communication withthe remote terminal and the master station. Compared with othersimilar units, the new unit outperforms in terms of real-time,precision and reliability, which can fully meet with the high-speeddevelopment of distribution automation system.