Sensitivity Characterization of Zeta DC-DC Converter to Coupling Capacitance Deviations

This study investigates the sensitivity of the Zeta
DC-DC converter to variations in the coupling capacitance, a
critical component that directly influences energy transfer,
transient behavior, and electromagnetic compatibility (EMC).
Through a simulation-based approach in MATLAB/Simulink,
the impact of realistic manufacturing deviations in the
coupling capacitor is evaluated. A series of frequency-domain
analyses are conducted by injecting single current pulses at key
nodes of the circuit and observing the resulting voltage
responses. The variations in the coupling capacitance, modeled
within a commercial tolerance step above and below the
nominal value, reveal significant changes in resonant peaks,
output ripple, and overall system stability. The findings
highlight that even small parameter deviations can induce
pronounced shifts in dynamic behavior, necessitating
conservative component selection and sensitivity-aware design
practices. This work emphasizes the importance of small-signal
analysis and node-based spectral evaluation in enhancing the
robustness and EMI performance of Zeta converter
implementations.