High-voltage motors refer to motors with rated voltages above 1000V. Common voltages used are 6000V and 10000V, with some also operating at 3300V and 6600V due to varying electrical grid standards abroad. High-voltage motors are produced because motor power is directly proportional to the product of voltage and current. Therefore, as the power of low-voltage motors increases to a certain extent (e.g., 300KW/380V), it becomes difficult to increase the current beyond the allowable capacity of the conductors, or it becomes too costly. Increasing voltage is necessary to achieve high power output. The advantages of high-voltage motors are their high power and strong shock resistance; the disadvantages are their high inertia, making both starting and braking challenging.