Impedance monitoring of a modular electrolysis system

An alternating current (AC) impedance spectroscopy system, comprising:

• a power factor corrected (PFC) rectifier electrically connectable to an AC power source via an AC split bus and to a direct current DC/DC converter via a first DC bus, wherein the PFC rectifier includes:
• a plurality of electric power inverters electrically connectable to respective AC busses of the AC split bus;
• a first capacitor and a second capacitor electrically connected in parallel to the plurality of electric power inverters via a middle DC bus at a DC-link midpoint;
• and
• an auxiliary electric power converter electrically connected to the DC-link midpoint via the middle DC bus and electrically connectable to the direct current DC/DC converter via the first DC bus, the auxiliary electric power converter configured to draw a reactive power amount from the DC-link to cancel a ripple current drawn by the DC/DC converter and comprising:
• a third capacitor electrically connected in parallel to the first capacitor and a fourth capacitor electrically connected in parallel to the second capacitor;
• and
• a filtering inductor electrically connected to the third capacitor and the fourth capacitor in parallel, wherein current from the DC-link midpoint is alternately and controllably drawn through the filtering inductor or the third capacitor and the fourth capacitor.