Single-phase controllable energy consumption device and controllable energy consumption system of alternating current power grid

The invention relates to a single-phase controllable energy consumption device and a controllable energy consumption system of an alternating current power grid, and belongs to the technical field of controllable energy consumption devices. The single-phase controllable energy consumption device comprises an energy consumption resistor and N cascaded energy consumption valves, the energy consumption resistor and the N cascaded energy consumption valves are connected in series to form an energy consumption branch, each energy consumption valve comprises a controllable valve and a rectification module, the alternating current side of the rectification module is used for being connected with single-phase power of an alternating current power grid, and the controllable valves are arranged on the direct current side of the rectification module; the overvoltage protection circuit is used for conducting when the AC power grid is overvoltage so as to conduct the energy consumption branch. When overvoltage occurs in t