Controlling a Servo Motor with a VFD

Hello everyone,

 I am new to Servo Motors. A client I have for an automation project wants to see if it's possible to get rid of some servo drives and contorl the servo motors with VFDs. The servos they have are Mavilor BLS112A and Mavilor BLS113A. 

Has anybody done this? Is it possible? What are the implications?

Thanks in advance.

May you explain what is VFD?

Variable Frequency Drive or sometimes referred to as a VSD, Variable Speed Drive.

An electronic module that you can use to control 3 phase motors from. I am familiar with them for large motors up to 40KW for downhole pump control but not familiar with their use with Servo Motors.

A quick Google search throws up a load of information that the OP might find more usable but it appears it can be done with some caveats depending on what the motors are driving. For me, the system only runs in 1 direction, CW but the VFD, through the comms port (Modbus or CANopen) can be used to run forward or reverse with programmable ramp rates etc.


 Thank you very much for your replies. Well, the main thing is to find a drive that can run a Permanent Magnet AC Motor, I have found some recently, but unfortunately, information about the type of resolver used by the motor is very little. For example, I found that AB PowerFlex 700S drives can run this type of motors and have an option for resolver input, but they don't show much compatibilities with resolvers that are not manufactures by Allen-Bradley, and the info of the embedded resolvers that the Mavilor motors use is not much.

Now, I would like to ask if some of you know. What could be the implications of using a drive for open loop control of PM AC motors? I found that Yaskawa drives offer control for these motors with two different open-loop methods (Voltage control method and filed-oriented current control method). As I said, I am new to servos and new to PM Motors as well, so would this ind of control be ineffective?

Thanks in advance.

I know you’re a new person on the forum, so I don’t want to come off too harsh, but why did you pick this forum to ask about industrial size/capability servo motors and VFDs? That’s pretty far from any normal discussion here - which is .Net Micro Framework and Gadgeteer, as well as a smattering of many other (somewhat) related things.

Hello Brett,

 I found a topic kind of related to my current question in this forum, it was on "archive" and some users gave some answers to it, so I thought probably I could get some help with it, despite the fact that the forum is not about Industrial Automation.