Power Balance Equation about the Numerical Control Machine Tool’s Main Driver System Driven by Variable Voltage Variable Frequency

In view of the characteristics of energy transmission in the running processes of numerical control (NC) machine tool driven by variable voltage variable frequency (VVVF), an energy flow model of main driving system is established. The power transition characteristics of main motor and mechanical transmission system and the energy loss on every section are analyzed. Finally, the dynamic power balance equation of the whole main drive system is established. Comparing with the equation of common machine tools, this equation has three characteristics. The wide application prospect of the equation is shown by the application analysis and practices.