Open AccessHybrid control of the dc–dc SRC operating below resonance
Author(s) -
Afshang Hamid,
Tahami Farzad,
MollaAhmadian Hamed
Publication year - 2017
Publication title -
iet power electronics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.637
H-Index - 77
eISSN - 1755-4543
pISSN - 1755-4535
DOI - 10.1049/iet-pel.2015.0362
Subject(s) - control theory (sociology) , harmonics , voltage controlled oscillator , controller (irrigation) , converters , voltage , operating point , charge pump , power electronics , electronic engineering , computer science , topology (electrical circuits) , engineering , electrical engineering , capacitor , control (management) , agronomy , artificial intelligence , biology
Control and stabilisation of the resonant converters are essential problems in power electronics. The conventional model of the dc–dc series resonant converter (SRC) is derived using the sinusoidal approximation and generalised averaging followed by linearisation about an operating point. This model involves considerable approximation and is not applicable for large variation of load and supply voltage. The authors have already proposed a direct piece‐wise affine (DPWA) modelling and control approach for the SRC that operates above resonant frequency. However, the DPWA technique is not applicable to an SRC that operates below resonance because of the presence of harmonics. In this study, a dynamic voltage‐controlled oscillator (VCO) is introduced, so that the overall system consisting of the proposed VCO following by the SRC is modelled as a PWA system. Then, a hybrid controller is designed in order to regulate the dc output voltage of the SRC operating below resonance. Also, the stability analysis of the closed‐loop system is presented in the form of linear matrix inequalities. A prototype of the SRC is constructed and the proposed hybrid controller is implemented on a digital signal processor (DSP) core. The simulation and experimental results show the effectiveness of this modelling and control approach.