Robot arms are being used in many fields at now, as the core of it, FOC plays the role in controlling function. This paper provides an overview of the specific function for MOSFET circuit used in FOC driver, which could reduce the loss of energy, improve the efficiency and extend the life of machine. Firstly, paper provides the three-phase inverter bridge circuit to produce eight states, which forms the SVPWM to control the electronic motor. Next, we do simulation in MATLAB to observe the specific motor states and the voltages in output. Finally, using different simulation environment to get the comparison with the expectation and raise the improvement of efficiency and power. This paper pays much attention to the introduction of three-phase inverter bridge and the SVPWM used in control motor.