Ablation system, methods, and controllers

A multi-electrode ablation system comprising:

• a power supply configured to be coupled to a plurality of electrodes by a common return path;
• and
• a controller configured to:
• measure a first current through the common return path when a first voltage is applied by the power supply to a first electrode of the plurality of electrodes;
• measure a second current through the common return path when a second voltage is applied by the power supply to a second electrode of the plurality of electrodes;
• measure a third current through the common return path when a third voltage is applied by the power supply concurrently to the first electrode and the second electrode;
• and
• determine a common path impedance based at least in part on the first voltage and the first current, the second voltage and the second current, and the third voltage and the third current.

A controller for a multi-electrode ablation system including a plurality of electrodes and a power supply, the plurality of electrodes coupled to the power supply by a common return path, the controller comprising:

• a processor;
• and
• a memory device, the memory device including instructions that, when executed by the processor, cause the processor to:
• measure a first current through the common return path when a first voltage is applied to a first electrode of the plurality of electrodes;
• measure a second current through the common return path when a second voltage is applied to a second electrode of the plurality of electrodes;
• measure a third current through the common return path when a third voltage is applied concurrently to the first electrode and the second electrode;
• and
• determine a common path impedance based on the first voltage and the first current, the second voltage and the second current, and the third voltage and the third current.

A multi-electrode ablation system comprising:

• a plurality of electrodes;
• a return electrode;
• a power supply configured to be coupled to the plurality of electrodes and the return electrode, wherein a conduction path between the plurality of electrodes and the return electrode defines a common return path of the system;
• and
• a controller coupled to the power supply, the controller configured to:
• couple an output voltage of the power supply to the plurality of electrodes;
• determine a therapeutic resistance associated with each electrode of the plurality of electrodes and a resistance of the common return path;
• and
• generate a notification when the determined resistance of the common return path exceeds a first threshold value.