Modular structure applied to numerical control machine tool control system

A modular structure applied to a numerical control machine tool control system comprises an HMI (Human Machine Interface) and a communication bus, and is characterized in that: each function program of the system is packaged in each module, an input end and an output end of the each module in a PLC (Programmable Logic Controller) pedestal are correspondingly communicated with pins of a numerical control system PLC processor and a power supply module through a data bus and a power supply bus; a PLC internal storage area is provided with a function selection parameter quantity checking module, an output end of the function selection parameter quantity checking module is connected with a basic function database module part through an input signal mapping module, the basic function database module part comprises a system starting module, an axle control module and an auxiliary function selection module, wherein the all modules respectively have an input interface and an output interface with the basic function da