求翻译：矢量控制的关键是磁场的准确定向，传统的电压模型和电流模型都过分依赖于电机的参数和转速，使得电机的低速性能较差。是什么意思？

Vector control is the key to the accuracy of the magnetic field orientation, the traditional model of voltage and current models are too dependent on motor parameters and speed, the motor's low speed performance is poor.

The key is the magnetic field vector control accurate orientation, the traditional voltage models and current models are overly dependent on the electrical parameters of the motor and speed, making low-speed performance is poor.

The vector control key is the magnetic field accurate direction detection, the traditional voltage model and the electric current model all excessively relies on the electrical machinery parameter and the rotational speed, causes the electrical machinery the low-speed performance to be bad.

Vector control is the key to accurate orientation of the magnetic field, the traditional model of voltage and current models are too dependent on the parameters of the motor and speed, making motor low-speed performance is poor.

The key that the vector controls is the accurate orientation of the magnetic field, traditional voltage model and current model all too depend on parameter and rotational speed of the electrical machinery, make the low-speed performance of the electrical machinery relatively bad.