Modular subsea control system

A mineral extraction system, comprising:

• a riser configured to extend between an offshore vessel and a wellhead coupled to a mineral deposit, wherein the riser comprises a blowout preventer comprising an annular sealing device configured to block a flow of fluid exiting the wellhead;
• and
• a modular subsea control system, comprising:
• a first control module positioned within the riser and above the annular sealing device of the blowout preventer, wherein the first control module comprises a first electronics module configured to output and receive one or more control signals, an energy storage unit, and a hydraulics system configured to generate a flow of pressurized fluid;
• and
• a second control module positioned within the riser and below the annular sealing device of the blowout preventer, wherein the second control module comprises:
• a second electronics module configured to output and receive additional control signals, wherein the second electronics module is communicatively coupled to the first electronics module, and wherein the first electronics module is configured to power the second electronics module by controlling a flow of power from the energy storage unit to the second electronics module;
• and
• a plurality of valves configured to adjust operations of the mineral extraction system, wherein the plurality of valves is communicatively coupled to the second electronics module, the plurality of valves is fluidly coupled to the hydraulics system, and the plurality of valves is configured to control the flow of the pressurized fluid to adjust operations of the mineral extraction system.