This study proposes a method of determining the input impedance of a phase shift modulated dual active bridge (DAB) converter in closed-loop operation. Input impedance is an important characterization of converter behavior, particularly in regards to interactions with external sources or systems. When converter models are available, model-based determinations of input impedance are possible through the application of the Extra Element Theorem (EET). However, DAB converters are not easily modeled using standard techniques due to their high-frequency ac stage. Instead, DAB models are derived using generalized average modeling (GAM). The GAM approach allows ac power stages to be modeled accurately but creates difficulties for model-based calculations of closed-loop impedances. This study simplifies determinations of closed-loop input impedance for DAB converters by deriving standalone expressions for the driving point impedances needed to apply the EET. These expressions allow the closed-loop input impedance to be calculated for any linear controller without the derivation of a corresponding closed-loop model. The values of input impedance calculated from these expressions are validated through comparison to experimental results from hardware tests.
- Electric Impedance Measurement,
- Linear Control Systems,
- Power Converters,
- Power Electronics,
- Closed-Loop Operation,
- Driving Point Impedances,
- Dual Active Bridge Converter,
- Dual Active Bridges,
- Extra Element Theorem,
- Generalized Average Models,
- Linear Controllers,
- Phase Shift Modulation,
- Electric Impedance,
- Generalized Average Modeling,
- Impedance Criteria,
- Impedance,
- Mathematical Model,
- Transfer Functions,
- Integrated Circuit Modeling,
- Harmonic Analysis,
- Topology,
- Analytical Models
Available at: http://works.bepress.com/jonathan-kimball/70/