AABC 2014 ECCAP Symposium - Large EC Capacitor Technology and Application - Session 3

Short term considerations or long term value? Which is right in this day and age of electric grid upheaval and revolution especially as it pertains to energy storage? There is no shortage of technical arguments and support for expanding energy storage associated with the grid. New sources of generation, new demands on the aging and crumbling infrastructure, new technologies available to solve problems, old and new, all play into the equation. The decision matrix is huge and the pattern of making short term decisions in favor of the right decisions continues to take its toll. Expecting that to change is a long shot, but unless something gives, our future is probably not much brighter than the present. And if we continue heading as we are, the future will keep moving out further and further from the present and we may never get there. We are not exactly kicking the can down the road, but certainly we are not pulling the trigger aiming at the big elephants in the room. Society is counting on us and big business holds the keys to success. We cannot continue to postpone the advanced technology introductions that can change the face of the challenge. This presentation will look at the value equation for energy storage on the grid and make the case for capacitive energy storage as a smart play now and going forward.

During this presentation I’ll provide technical detail into why the designs and uses of ultracapcitors make the technology a reliable technical solution for light rail. I will explain the effectiveness of ultracapacitors within this application by highlighting the following topics:

• Two uses for ultracapacitors in light rail: Rolling Stock & Way Side Storage
• The requirements of an energy storage system (ESS) in rail and what challenges this creates
• The benefits of using ultracapacitors and why efficient throughput is key for the rail market
• Features of product design that can improve an ultracapacitor’s efficiency

I’ll conclude with a summary and offer the opportunity for questions or the expansion on any comments made during the presentation.

This report presents a solution to improve the dynamic response, efficiency, productivity, and fuel consumption of a diesel-engine generator set for hydraulic mining shovels using a high power energy storage system. A 2.25 MW ultracapacitor system is applied to overcome the sluggish dynamic response of a diesel-engine during sudden load changes and limit the engine output power requirement by maintaining an optimal engine speed. When the load’s rate of change increases above a specified rate limit, the ultracapacitors supplement power to the load so that the engine power rate of change can be managed to track a maximum optimal value. In addition to the diesel-engine dynamic improvement, the ultracapacitors are also used to limit the diesel engine peak power requirement to well below machine peak power which allows for the use of a smaller engine and results in higher fuel savings on the machine. A DC/DC converter is used to transfer energy back-and-forth between the ultracapacitor system and the DC bus. Sophisticated control strategies are designed, implemented, and applied to the system to perform complete machine power management. Simulation and experimental results are presented, which validate the proposed scheme.

In 2003 a retrofit able hybrid for start/stop intensive commercial vehicles needed a powerful and light weight energy storage system. This paper describes how ultracapacitor modules were used to provide an effective high power energy storage system for the Crosspoint Kinetics Series-3000 hybrid system. Performance data from field and life testing will be presented. Performance advantages of a flux weakening P.M. motor will be discussed along with the impressive fuel and emissions savings in commercial fleet use.

• Commercial vehicle hybrid background
• Ultracapacitors are an ideal energy storage solution- high power and low weight
• S-3000 hybrid system configuration
• Performance and user notes
• Life testing results
• Performance advantages
• Field experience
• Typical fuel and emissions saving
• Summary and conclusion

The need for energy storage devices which can deliver high power is intensifying. Typically batteries are preferred for energy storage due to their large energy densities. In many applications however, power and low temperature performance are more critical parameters. Supercapacitors have a unique capability to deliver their stored energy with a large amount of power in a short period of time.

In a typical engine, a lead-acid battery is used both to start the engine and to run the electronics while the vehicle is operating. Starting an engine requires a large amount power, and a non-trivial amount of energy. A supercapacitor can easily provide the power to start, over a much wider temperature range. Due to its extremely long cycle life, a supercapacitor will usually last as long as the life of the vehicle and also have enough energy for multiple successive start attempts. KBI and Saft have worked together over the last five years to develop the KAPower nickel capacitor devices. They are proving to be more reliable, longer lasting, and less costly to use for engine starting.

With this presentation we aim to:

• Show the basic principles of applying this technology for engine starting
• Discuss commercial programs that are pursuing Nickel Carbon Capacitor technology
• Cover the characteristics and specifications engineers need to consider when selecting the appropriate device for their application.
• Present actual cold room charts and data to help further explain the operational parameters involved in the successful implementation of the technology.

Saft asymmetric nickel capacitors, in particular, demonstrate a reliable, safe and long-lasting alternative for power delivery in many current and emerging technologies. Here we will provide a more in depth review detailing:

• The advantages of Saft nickel capacitors in high power applications:
  • Cold-temperature performance
  • Low self-discharge rates
  • Safety and reliability
   
• Recent technological improvements of Saft nickel capacitors:
  • Development of carbon bonded electrode
  • Flexibility of design
  • Performance parameters and alternative uses
   
• Summary:
  • KBI and Saft technologies offer the best and most cost effective approach to engine starting for military and commercial applications
   

Liebherr builds heavy machinery for the use in ports, on constructions sites, for mining etc. All these machinery has a different source of energy. Some will run on diesel engines and others are powered directly from the grid. Due to the electrification of the drive chain more and more machinery are using electric motors for their operation process. Because many operations processes are cyclic there is a fast growing potential for electric storage solutions. The Liebherr-Components Biberach GmbH is the center of competence for electric drive systems in the Liebherr group and thus the employees there took the chance to develop a fully integrated DLC storage unit for mobile machinery.

In this presentation the initial situation is presented first, after this the drawbacks of existing solutions are depicted and finally the new approach found is explained.

• Experiences with DLC usage until now
  • Test on a rubber tyre gantry crane in a port since 2008.
  • Test on an excavator which was presented at the BAUMA fair in 2013.
  • All test cases showed a high and in some applications very high potentials for savings.
   
• Disadvantages of the nowadays products
  • Very high initial costs results in a long time for the return on invest even if big savings could be assumed. Therefore many potential projects were never realized.
  • As the caps, the design of the power electronics and the rating of the chokes is up to the project engineer there is need for a profound knowledge on this side which could not always be assumed since the project engineer might not have an electrical degree.
  • No real modular solution compromising all components needed (caps, power electronic, choke).
   
• New design
  • Caps, power electronics and chokes included resulting in a off the shelf product which can be used by without knowledge of DLC.
  • A modular approach of the new DLC storage unit makes is adaptable to many applications.
  • All environmental conditions are chosen that the storage unit is suitable for use in mobile equipment.
  • Cost optimized design to allow a return on invest period most customers could bear.
  • The first product is optimized to be connected to a dc link of a 400 V or 480 V motor.