M. Stephens

Power quality issues and solutions in the automotive industry

With just-in-time production schemes, todays automotive manufacturers stretch flexible-automation and supply-chain management to the limit. Unscheduled downtime at the main assembly plant or at the outsourced suppliers facility can lead to lower productivity and lost profits. When a plant recently experienced four-cycle voltage sag, over

CIGRE/CIRED/UIE JWG C4.110 - voltage dip immunity of equipment in installations - status April 2008

700,000 was lost in the following 72 minutes due to the shutdown of the process and required rework. With a myriad of robotics, programmable controllers and drive systems working in a real-time process environment, automotive manufacturing systems can be vulnerable to power quality issues. This paper explores areas of vulnerability from the body shop through the paint shop and final assembly and identify effective measures to increase the robustness of automotive process systems through this new premium service concept U.S. utilities such as TVA (Tennessee Valley Authority) along with Duke energy have joined EPRTs power quality in automotive research project This project promotes the concepts of solving power quality problems at the most economical level through empowering the end user with knowledge to solve power quality issues.

CIGRE/CIRED/UIE JWG C4.110, Voltage dip immunity of equipment in installations

This paper presents the status of the work, by April 2008, in C4.110, a joint working group by CIGRE, CIRED and UIE. The scope of the working group is to gather technical knowledge on the immunity of equipment, installations and processes against voltage dips, and to use this knowledge in the further development of methods and standards. The activities of the working group are divided in seven ldquochaptersrdquo. Chapters 1 and 7 are introduction and conclusions, respectively. Chapter 2 gives a general description of voltage dips as they appear at the terminals of sensitive equipment. Chapter 3 describes the performance of equipment and processes during voltage dips. This chapter also includes recommendations on the design of processes. In Chapter 4 the results from Chapter 2 and Chapter 3 are combined to set requirements for the dip characteristics that should be included in immunity testing. Chapter 5 is the data gathering chapter, covering data on voltage-dip statistics at different locations, but also data on the economics of equipment immunity and testing. Finally, in Chapter 6, recommendations for immunity objectives will be given. Important contributions of the working group are: a check-list of voltage dip characteristics to be used early in the design of equipment; a methodology to assess the performance of a complete installation and to include voltage-dip performance in the design of the installation; recommendations for characterization testing of equipment against voltage dips; recommendations for voltage-dip immunity of equipment.