THE IMPROVEMENT OF MAINTENANCE CHAIN FOR LARGE-SIZE TRANSFORMER PROVIDER

THE IMPROVEMENT OF MAINTENANCE CHAIN FOR LARGE-SIZE TRANSFORMER PROVIDER内容摘要：

IEEM535200 Electronic Enterprise Integration _ Group 4 THE IMPROVEMENT OF MAINTENANCE CHAIN FOR LARGE-SIZE TRANSFORMER PROVIDER Penny Liua, Elsie Chena, Jimmy Changa a Department of Industrial Engineering and Engineering Management, National Tsing Hua University, 101, Sec. 2 Kuang Fu Road, Hsinchu, 30013, Taiwan ABSTRACT Stable and reliable power supply is essential to industry and our daily life. In order to avoid the unexpected shortage of power which may result in losing money or people and danger to society, the methods such as experientially self-maintained rulebase and periodic maintenance are adopted. However, the existing methods fail in predicting and preventing emergency shutdowns efficiently. Thus, the objective of this project is to propose an improved maintenance flow for large-size transformers, the critical equipment in power supply chain, to enhance the maintenance efficiency by constructing a preventive alarm system and reduce human resource involved in largesize transformer maintenance chain via Income Suite as the business process modeling and simulation tool. Keyword: periodic maintenance, experientially self-maintained rule-bases, large-size transformer 1. INTRODUCTION The large-size power transformers play the important role in power supply transmission and distribution network. In order to minimize power loss during the transmission, step-up transformers are used to raise the input voltage of generating station which is around 500~600V to higher output voltage which is around 33,000~34,000V, and the large-size transformers (the case-study transformer) step up the voltage to 220KV after receiving the power from power collection transformer for transmission. Finally, step-down transformers will step down the input voltage to lower output voltage around 110V for end users. Besides, each large-size transformer costs NT$ 100 million[1], once the large-size transformer is out of order, the power supply will be interrupted and may incur huge property loss and human casualties. Thus, preventive maintenance and real time monitoring are crucial to avoiding 1 / 12 IEEM535200 Electronic Enterprise Integration _ Group 4 the unexpected shut down of large-size transformer. This research aims at reengineering the maintenance chain for large-size transformer providers to enhance their competitiveness. Income Suite based on Petri-net [2][3] is applied as the business process modeling tool in this research, and ASP. Net web-site is created to support the real-time monitoring system. 2. MODEL DISPLAY AND ANALYSIS There are two kinds of input objects in as-is maintenance chain, one is periodic maintenance request and the other is shutdown alarm. The large-size transformer provider will execute a periodic maintenance based on the utilization of large-size transformer. On the other hand, the urgent maintenance request is generated due to unexpected shutdown. The as-is maintenance chain and the recover drill down model are shown in Figure 1 and Figure 2. And the details of activities and objects are listed in Table 1 and [4]. Figure 1 Current large-size transformer maintenance chain Figure 2 Recover drill down model Table 1 Details of activities in as-is model Activity Operation Periodic Description The large-size transformer is operated in customer’s site. Maintenance staff of large-size transformer provider will execute a 2 / 12 IEEM535200 Electronic Enterprise Integration _ Group 4 Maintenance basic maintenance such as rust-removing, mechanical parts testing Preliminary and replacement. Once the shutdown occurs, the maintenance staff of large-size Diagnose Notify Related provider will examine the machine initially. Once the shutdown occurs, the related functional departments of Functional large-size transformer provider will be informed by customer. Department Recover This activity can be drilled-down into three sub-activities: Diagnose, Allocate Maintenance Crew & Resource and Repair. After the diagnosis is issued by the engineer of large-size transformer provider, the coordinator shall allocate the resources for repair. Table 2 Details of objects in as-is model Object Description Healthy Transformer Including Notification of Periodic information. The large-size transformer provider will issue notification Maintenance Shutdown Alarm for maintenance to their customers periodically. Once the transformer is out of order, customer will inform Preliminary Report Maintenance Request the