Please use this identifier to cite or link to this item: http://localhost/handle/Hannan/234199
Title: Digital Implementation of Soft Start-Up and Short-Circuit Protection for High-Frequency LLC Converters With Optimal Trajectory Control (OTC)
Authors: Chao Fei;Fred C. Lee;Qiang Li
Year: 2017
Publisher: IEEE
Abstract: Achieving soft start-up and short-circuit protection have always been challenging for resonant converters due to severe stresses in the resonant tank. Optimal trajectory control (OTC) has been proven to be the most effective control method to optimize energy delivery with given stresses. This paper proposes a method to implement soft start-up and short-circuit protection for <italic>LLC</italic> converters by using low-cost microcontrollers (MCUs) with minimum stresses and optimal energy delivery. Our current understanding of the relationship between the switching frequency and the output voltage is based on the state-plane analysis, and the requirement for the controllers is significantly reduced when using the lookup table. Further improvement enables the application of the proposed control method to high-frequency <italic>LLC</italic> converters without increasing the cost for the controllers. This paper proposes a method to protect the <italic>LLC</italic> converter from abrupt short-circuit with low-cost MCUs, which improves transient response to short-circuit significantly, and investigates limitations when operating the high-frequency <italic>LLC</italic> converter under short-circuit conditions. The proposed methods minimize the CPU resource requirement and can be further integrated with other state-trajectory control functions within one MCU. Experimental results are demonstrated on a 500-kHz 1-kW 400-V/12-V <italic>LLC</italic> converter with 60-MHz MCU TMS320F28027.
URI: http://localhost/handle/Hannan/234199
volume: 32
issue: 10
More Information: 8008,
8017
Appears in Collections:2017

Files in This Item:
File SizeFormat 
7752990.pdf1.33 MBAdobe PDF
Title: Digital Implementation of Soft Start-Up and Short-Circuit Protection for High-Frequency LLC Converters With Optimal Trajectory Control (OTC)
Authors: Chao Fei;Fred C. Lee;Qiang Li
Year: 2017
Publisher: IEEE
Abstract: Achieving soft start-up and short-circuit protection have always been challenging for resonant converters due to severe stresses in the resonant tank. Optimal trajectory control (OTC) has been proven to be the most effective control method to optimize energy delivery with given stresses. This paper proposes a method to implement soft start-up and short-circuit protection for <italic>LLC</italic> converters by using low-cost microcontrollers (MCUs) with minimum stresses and optimal energy delivery. Our current understanding of the relationship between the switching frequency and the output voltage is based on the state-plane analysis, and the requirement for the controllers is significantly reduced when using the lookup table. Further improvement enables the application of the proposed control method to high-frequency <italic>LLC</italic> converters without increasing the cost for the controllers. This paper proposes a method to protect the <italic>LLC</italic> converter from abrupt short-circuit with low-cost MCUs, which improves transient response to short-circuit significantly, and investigates limitations when operating the high-frequency <italic>LLC</italic> converter under short-circuit conditions. The proposed methods minimize the CPU resource requirement and can be further integrated with other state-trajectory control functions within one MCU. Experimental results are demonstrated on a 500-kHz 1-kW 400-V/12-V <italic>LLC</italic> converter with 60-MHz MCU TMS320F28027.
URI: http://localhost/handle/Hannan/234199
volume: 32
issue: 10
More Information: 8008,
8017
Appears in Collections:2017

Files in This Item:
File SizeFormat 
7752990.pdf1.33 MBAdobe PDF
Title: Digital Implementation of Soft Start-Up and Short-Circuit Protection for High-Frequency LLC Converters With Optimal Trajectory Control (OTC)
Authors: Chao Fei;Fred C. Lee;Qiang Li
Year: 2017
Publisher: IEEE
Abstract: Achieving soft start-up and short-circuit protection have always been challenging for resonant converters due to severe stresses in the resonant tank. Optimal trajectory control (OTC) has been proven to be the most effective control method to optimize energy delivery with given stresses. This paper proposes a method to implement soft start-up and short-circuit protection for <italic>LLC</italic> converters by using low-cost microcontrollers (MCUs) with minimum stresses and optimal energy delivery. Our current understanding of the relationship between the switching frequency and the output voltage is based on the state-plane analysis, and the requirement for the controllers is significantly reduced when using the lookup table. Further improvement enables the application of the proposed control method to high-frequency <italic>LLC</italic> converters without increasing the cost for the controllers. This paper proposes a method to protect the <italic>LLC</italic> converter from abrupt short-circuit with low-cost MCUs, which improves transient response to short-circuit significantly, and investigates limitations when operating the high-frequency <italic>LLC</italic> converter under short-circuit conditions. The proposed methods minimize the CPU resource requirement and can be further integrated with other state-trajectory control functions within one MCU. Experimental results are demonstrated on a 500-kHz 1-kW 400-V/12-V <italic>LLC</italic> converter with 60-MHz MCU TMS320F28027.
URI: http://localhost/handle/Hannan/234199
volume: 32
issue: 10
More Information: 8008,
8017
Appears in Collections:2017

Files in This Item:
File SizeFormat 
7752990.pdf1.33 MBAdobe PDF