Consistent with an aspect of the present disclosure, a backup fuel cell, for example, is coupled to a utility power grid, through a power conversion circuit. The power conversion circuit may include an inverter circuit, pulse generating circuit and control circuit. The inverter circuit is configured to receive a DC signal and output a first AC signal, and the pulse generating circuit generates a pulse signal in response to a change in a parameter associated with a second utility generated AC signal. The control circuit is coupled to the inverter circuit, and is configured to receive the pulse signal. In addition, the control circuit supplies a control signal to the inverter circuit to adjust a parameter associated with the first AC signal in response to the pulse.