Abstract
The cooperative triple-phase-shifted modulation (CTPS) for the isolated dual-active bridge (DAB) DC-DC converter has the advantages of zero dual-DC side flow back currents and best current characteristics. However, the mathematical model and corresponding closed-loop control configuration of the DAB converter driven by CTPS are not presented so far. In order to solve this problem, in this paper, the average state space model of the DAB converter driven by CTPS is established for the first time. It is proven that the DAB converter driven by CTPS is a zero-order system and it is not necessary to construct an inner inductor current closed-loop control loop in the entire closed-loop control configuration of DAB converter. Furthermore, the average power model is derived. Two control strategies based on the resulted average power model when the DAB converter is connected to DC microgrid or a pure resistive load are proposed to realize the precise control of the transfer power or the output voltage, respectively. The detailed experimental results verify the correctness of the established mathematical model and the closed-loop control strategies.
Highlights
The isolated dual active bridge (DAB) DC-DC converter has the advantages of bidirectional power flow and bidirectional boost/buck voltage conversion, and fast dynamic response
Known from the average state-space model, the DAB converter controlled by cooperative triple-phase-shifted modulation (CTPS) is a zero-order system and there is no transient process between the average transfer power or the inductor current and the phase shifts
EXPERIMENTAL RESULTS AND DISCUSSION The experimental prototype of DAB DC-DC converter based on DSP chip TMS320F28335 is built as shown in Fig. 5 to validate the proposed control strategies
Summary
The isolated dual active bridge (DAB) DC-DC converter has the advantages of bidirectional power flow and bidirectional boost/buck voltage conversion, and fast dynamic response. In [22], the expression of average transfer power as a function of outer phase shift with the singlephase-shifted modulation (SPS) is derived to calculate the actual phase shift according to the power reference In this way, the small-signal model is not used and in theory, the dynamic performance keeps constant in the entire power range because the actual performance is in independent of the pre-chosen operation point, which is necessary in the smallsignal model based control system. (2) Based on the zero-order system characteristics, the control strategies of the DAB converter when it is connected to a DC microgrid or serves alone as a DC source supply are proposed based on the obtained power model, on the one hand, to realize the precise control of the transfer power and output voltage, on the second hand, to simplify the closedloop control configuration and reduce the design burden of the controller parameters.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
