Research Of Transformer OLTC Measuring System Based On Embedded System

As the only often active component of the transformer, the On-load-tab-changers' stability directly determines weather the transformer can run safely. As a result, when detecting and repairing, it need to carry out some relative experiments in order to ensure the quality of the installation or detection, and make sure that the OLTC can constantly salty run. The switch curve test of the OLTC is a very important test item. Through this test, we can estimate whether the switch can correctly active, as a result, we can estimate whether the OLTC presents some problems, such as the abnormal electromotor, the anamorphic insulator, the burned-out joint, and the break transmission axes, etc.This paper elaborates on the development process of the transformer OLTC test instrument based on the S3C2410 processor and theμC/OS-Ⅱreal-time system. First, it analyses the function and precision requirement of the instrument, and then introduces the design scheme:On the hardware, this system uses the Samsung S3C44B0X as platform kernel. It includes much module and has low power consumption. Besides, this system adds the Flash storage, SDRAM, power supply, crystal pulsator, the debug JTAG inter face, the RS232 interface, and the man-machine LCD/keyboard interface.On the software, this sytem uses theμC/OS-Ⅱreal-time multiple tast entironment in order to ensure that the instrument can real-time measure data. This system can divided into two part: one is to achieve the collection and storage of the OLTC resistance value which means that the instrument is to collect the three-phase transitional resistance data when measuring the OLTC active data; the other part is to achieve the communication between the instrument and PC, which means that the instrument is to carray out the relative tast according to the request when receiving the instruction from the PC.The main testing parameters of this OLTC testing system includes: transitional curve, transitional time, every instantaneous transitional resistance value and the the three-phase corresponding performance, etc. According to every testing result of this instrument, the operational function can meet the design requirement, and the measuring precision can also achieve the technique index. Besides, the curve recorded by the instrument is closed consistent to the curve recorded by the oscillograph.