Design Modifications to Reduce a Brushless Exciter Response Time


  • Esnick Felissaint Esnick Felissaint is with Siemens-Energy, 4400 N Alafaya Trl, Orlando, FL. 32826
  • Kalpathy Sundaram Kalpathy Sundaram is with the University of Central Florida, 4000 Central Blvd, Orlando, FL. 32816


Brushless exciter, static exciter, response ratio, conventional response time, high initial response, permanent magnet generator (PMG), ac exciter stator, ac exciter armature, IEEE model, voltage regulator, ceiling voltage, ceiling current, response time


As an alternative to converting a brushless exciter to static excitation in order to improve an exciter’s response time, conversion of the existing conventional brushless exciter is possible. A high initial response (HIR) brushless excitation system has the ability to force its output to ceiling voltage in 0.1 second or less, which is a response time similar to a static excitation system. To achieve the required fast response time, various modifications to the existing exciter components are required, including the ac exciter stator, permanent magnet generator (PMG), and voltage regulator. This paper describes those required modifications and associated technical information. This paper presents a concept solution that decreases the response time of a brushless exciter in order to respond to grid disturbances via the excitation system, while minimizing modification of the existing excitation system configuration.    


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How to Cite

Esnick Felissaint, & Kalpathy Sundaram. (2024). Design Modifications to Reduce a Brushless Exciter Response Time. International Journal of Sciences: Basic and Applied Research (IJSBAR), 73(1), 154–171. Retrieved from