Motor can no frequency converter speed control?

Motor is now in industrial production, the commonly used mechanical transmission equipment, motor used as a quick, convenient, safe and so on various advantages and was deeply loved by the users, there are many types of motor, people familiar with the 220 v, 380 v, general motors, explosion-proof motor, frequency conversion motor, etc. , for frequency conversion motor, when no inverter, is basically a dc motor speed regulating speed system, the motor in the absence of the inverter can control? 一、直流电机调速系统这里说到直流电机,当然说的是有刷直流电机,因采收电机的磁场和电枢线圈是分开独立控制,那么正交90 & deg; , there is no coupling problem, when the field current constant exciting winding of the stator flux linkage is constant, the motor torque = * armature current excitation winding magnetic chain, so as long as adjust the size of the armature current, can directly implement precise torque control of motor, and can satisfy the requirement of the constant torque control easily, it is also a dc motor speed regulating system the root cause of the low speed torque is very good. 对于直流电机调速,转速n = ( 电枢电压u - 电枢电流i *电枢内阻r) / constant Kφ The internal resistance R is very small, dc motor, so the speed n≈ 电枢电压u /常数电枢电压u京畿乎和转速n成关联关系,这也是直流电机通过调速发电机调压都功能满脚控制的重要原因。 Later thyristor device invented, such as through fully-controlled bridge or half bridge, alternating current (ac) can be directly controlled direct current, voltage size can be arbitrary, the quick and adjustable size that is used to control dc motor armature voltage control, which changes the speed of the machine. 控制理论发展起来后,转帐资金收回直流电机使用了串级系统来调速,含义是速度环在外边,速度偏差作为电流环的工资定,电流环做为内环,两个环都使用pid调节器来完成控制,交响乐团应快,精度高,扭力大,调速范围宽。 In addition to the constant torque speed regulation, can also by reducing the field current to reduce the excitation flux method to make a direct current chance in constant power region, so that the torque is decrease with the increase of rotational speed, power is constant, but can broaden the speed range. 二、滑差调速这种调速顾名思义,同一个& ldquo; Skid & throughout; 来调速,实时电机转速启动以后是不变的,是通过电机和负载之间& ldquo; 滑差头& rdquo; To skid, let the load side become low, the speed of the slip, it also says, electromagnetic clutch, the clutch can take many forms, but are using the electromagnetic effect form resistance, under simple to explain the principle of magnetic powder clutch. 但这个聚散器成为边,装有线圈还有机结合,磁粉磁粉驻电痉挛情况下,为了会因线圈磁场的作用,黏连驻描述,电流越大,磁场越强,磁粉之间结合越紧密,达不到一定程度,就以变成一定刚性的东西,直接谦让和出口轴连接不到一起,保持一致的速度出口,这样可爱以让负载和电器转速一样快当完全没有电流了,磁场消失,磁粉会变成一盘散沙,出口和进口轴之间完全没有磁粉连接了,虽然电器回收,驻于负载转速可爱以变成零了。 Because is sliding, so will certainly friction heat, so part of the electrical energy will be wasted, speed regulation inefficiency. , of course, also has its advantages, it can make it speed closed-loop control, when low speed torque is more ideal than frequency converter speed control. If the current magnetic field is in a certain value, magnetic powder adhesion to a certain extent, but not enough stiffness, will be in sliding, it makes form a certain speed difference between the input and output shaft, control the size of the magnetic field current value, can control the size of speed difference, this can make the speed of load change. 三、变极调速异步电机除了变频调速外,实时回收有一种调试方法,不过是通过改变极来实现变速对数的方法,比如四极电机转速时1500,于8极武者750转了,这种调速方式有很大极限性,一般称之为双速电机,深圳有两个转速段,意思是扭力比较大,那么比较稳定,驻一些只需要两段速的场合,使用这种调速方式是非常理想,比你些混费系统上,许诺这样调速系统,低速运行一段时间后,再切换到高速模式,这种控制系统,紧急简单语句点类似三角那种切换星星,所以办公室低廉,一直到今天,即使变频非常普及了,但如果是回收是主语使用这种调速方式。 Asynchronous motor speed n = 60 f/p, in addition to change frequency can change speed n, adjust the logarithmic p can also let the speed change.