2
Mechanical characteristics of three-phase asynchronous motor is refers to the
speed of the motor n contact between electromagnetic torque Tem. Because rotational
speed n must be with the slip S corresponding relation, so the mechanical properties
are also commonly used Tem = f (S) to show that. Three-phase asynchronous motor
electromagnetic torque expressions have three way, namely physical expression,
parameter expression and useful expressions. Physical expression reflects the physical
essence of asynchronous motor electromagnetic torque, said clear electromagnetic
torque is the main magnetic flux and the rotor active current occurring in the course of
interaction. Parameter expressions reflect the electromagnetic torque and power
parameters and the connection between the motor parameters, using the type can
conveniently analyze the parameter changes on the influence of the electromagnetic
torque and the influence of various artificial features. Useful expressions are short,
easy to memory, are common in engineering calculation selection method.
电动机的最大转矩和发动转矩是反映电动机的过载才干和发动功用的两个
重要目标,最大转矩和发动转矩越大,则电动机的过载才干越强,发动功用
越好。
The maximum torque and a torque of the motor is overload of the motor ability
and function of the two important goals, the greater the maximum torque and a torque,
motor overload ability is stronger, a function, the better.
三相异步电动机的机械特性是一条非线性曲线,通常情况下,以最大转矩
(或临界转差率)为分界点,其线性段为安稳运转区,而非线性段为不安稳
运转区。固有机械特性的线性段归于硬特性,额外作业点的转速略低于同步转
速。人为机械特性曲线的形状可用参数表达式剖析得出,剖析时要害要捉住最
大转矩、临界转差率及发动转矩这三个量随参数的改动规则。
Mechanical characteristics of three-phase asynchronous motor is a nonlinear curve,
usually, to maximize the torque (or critical slip) as the cut-off point, its linear segment
for safe operation region, and nonlinear for unsafe working area. Inherent mechanical