The Chaotic-Based Control of Three-Port Isolated Bidirectional DC/DC Converters for Electric and Hybrid Vehicles

Abstract

Three-port isolated (TPI) bidirectional DC/DC converters have three energy ports and offer advantages of large voltage gain, galvanic isolation ability and high power density. For this reason this kind of converters are suitable to connect different energy sources and loads in electric and hybrid vehicles. The purpose of this paper is to propose chaotic modulation and the related control scheme for TPI bidirectional DC/DC converters, in such a way that the switching harmonic peaks can be suppressed in spectrum and the conducted electromagnetic interference (EMI) is reduced. Two chaotic modulation strategies, namely the continuously chaotic modulation and the discretely chaotic modulation are presented. These two chaotic modulation strategies are applied for TPI bidirectional DC/DC converters with shifted-phase angle based control and phase-shifted PWM control. Both simulation and experiments are given to verify the validity of the proposed chaotic modulation-based control schemes.

An Isolated Three-Port Bidirectional DC-DC Converter with Enlarged ZVS Region for HESS Applications in DC Microgrids

“…If we suppose that the phase shift angle under unity voltage gain (M = 1) is ϕ, and the phase shift angel to transfer same power under varying M is α. The relationship between ϕ and α is shown in (27) and (28). It is shown in (13) and (14) that with certain input voltage, resonant parameters and switching frequency, the peak value of resonant current is directly proportional to N which is shown in (29).…”

“…In [31,32], renewable source, battery and load are integrated to a three-port SR BDC. The driving frequency is 100 kHz, which is apparently higher than 20 kHz of TAB as shown in [26][27][28][29]. What's more, power flow among three ports can be controlled independently since there are only two SR tanks.…”

“…The three-port triple-active-bridge (TAB) converter shown in Figure 2, as the most widely disseminated isolated three-port topology, attracts a lot of attentions from researchers [23][24][25][26][27][28][29]. In [26], a TAB converter is used to deal with a hybrid energy source consisting of full cell and super capacitor.…”

“…In case of high power levels, switching frequency has to be reduced to get realizable inductance value. In [26][27][28][29] the driving frequency are all 20 kHz, and this will be detrimental for realizing high power density. Figure 1a shows the diagram of non-isolated three-port converter [18,19], and Figure 1b presents the topology of partly-isolated converter [20][21][22].…”

“…In case of high power levels, switching frequency has to be reduced to get realizable inductance value. In [26][27][28][29] the driving frequency are all 20 kHz, and this will be detrimental for realizing high power density. In order to solve problems of TAB mentioned above, a series-resonant (SR) based converter is proposed in [30].…”