TY - JOUR
T1 - Analysis of the soft-switching tuning effect on the figures of merit involved in the design of a class-e amplifier with finite dc-feed inductance
AU - Casallas, Ingrid
AU - Urbina, Robert
AU - Paez-Rueda, Carlos Ivan
AU - Perilla, Gabriel
AU - Pérez, Manuel
AU - Fajardo, Arturo
N1 - Publisher Copyright:
© 2021 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2021/7/2
Y1 - 2021/7/2
N2 - This paper explores the design of a Class-E amplifier with finite DC-feed inductance using three tuning methods. Furthermore, this work quantifies the impacts of the tuning process (referred to in this paper as the tuning effect) on the main figures of merit (FoMs) of this amplifier. The tuning goals were to guarantee two conditions: zero voltage and zero voltage derivative switching (i.e., soft-switching tuning). To the best of the authors’ knowledge, systematic tuning methods have not been analyzed before for this amplifier topology. Two of them are based on the iterative component tuning process, and they have been explored previously in the design of the conventional class-E amplifier with an RF choke inductance. The last tuning method explores the simultaneous adjustment of the control signal period and one amplifier capacitor. The analyzed tuning methods were validated by extensive simulations of case studies, which were designed following the power specifications of the Qi standard. In 100% and 96% of the case studies, zero voltage switching (ZVS) and zero-derivative voltage switching (ZDS) were achieved, respectively. Furthermore, we identified an unexpected behavior in the tuning process (referred to in this paper as the turning point), which consisted of a change of the expected trend of the soft-switching (i.e., ZVS and ZDS) point, and it occurred in 21% of the case studies. When this behavior occurred and converged to at least ZVS, the tuning process required more iterations and a large number of tuning variables. Additionally, after the tuning process, the total harmonic distortion and output power capacity were improved (i.e., in 78% and 61% of the case studies, respectively), whereas the output power, drain and added power efficiencies deteriorated (i.e., in 83%, 61% and 65% of the case studies, respectively) in the overall case studies. However, we could not identify an improvement in the overall FoMs related to the soft-switching tuning. Furthermore, the tuning impact was significant and produced some improvements and some deleterious effects for the FoMs in each case study, without a clear trend by FoMs or by tuning method. Therefore, the amplifier designer may choose the more favorable tuning method and the related FoM trade-offs for the required design specifications.
AB - This paper explores the design of a Class-E amplifier with finite DC-feed inductance using three tuning methods. Furthermore, this work quantifies the impacts of the tuning process (referred to in this paper as the tuning effect) on the main figures of merit (FoMs) of this amplifier. The tuning goals were to guarantee two conditions: zero voltage and zero voltage derivative switching (i.e., soft-switching tuning). To the best of the authors’ knowledge, systematic tuning methods have not been analyzed before for this amplifier topology. Two of them are based on the iterative component tuning process, and they have been explored previously in the design of the conventional class-E amplifier with an RF choke inductance. The last tuning method explores the simultaneous adjustment of the control signal period and one amplifier capacitor. The analyzed tuning methods were validated by extensive simulations of case studies, which were designed following the power specifications of the Qi standard. In 100% and 96% of the case studies, zero voltage switching (ZVS) and zero-derivative voltage switching (ZDS) were achieved, respectively. Furthermore, we identified an unexpected behavior in the tuning process (referred to in this paper as the turning point), which consisted of a change of the expected trend of the soft-switching (i.e., ZVS and ZDS) point, and it occurred in 21% of the case studies. When this behavior occurred and converged to at least ZVS, the tuning process required more iterations and a large number of tuning variables. Additionally, after the tuning process, the total harmonic distortion and output power capacity were improved (i.e., in 78% and 61% of the case studies, respectively), whereas the output power, drain and added power efficiencies deteriorated (i.e., in 83%, 61% and 65% of the case studies, respectively) in the overall case studies. However, we could not identify an improvement in the overall FoMs related to the soft-switching tuning. Furthermore, the tuning impact was significant and produced some improvements and some deleterious effects for the FoMs in each case study, without a clear trend by FoMs or by tuning method. Therefore, the amplifier designer may choose the more favorable tuning method and the related FoM trade-offs for the required design specifications.
KW - Class E
KW - Design methods
KW - Power amplifier
KW - Tuning
UR - http://www.scopus.com/inward/record.url?scp=85110278887&partnerID=8YFLogxK
U2 - 10.3390/electronics10141705
DO - 10.3390/electronics10141705
M3 - Article
AN - SCOPUS:85110278887
SN - 2079-9292
VL - 10
JO - Electronics (Switzerland)
JF - Electronics (Switzerland)
IS - 14
M1 - 1705
ER -