In the maintenance, transformation and upgrading of servo motor and servo driver projects, engineers often encounter compatibility problems that may have a negative impact on time schedule or budget, that is, the matching problem between servo motor and servo driver, which is not always as simple as people expected. How to ensure that the replaced driver matches the motor?
Please note the following potential problems.
To ensure that the replaced driver matches the motor, please pay attention to the following potential problems.
Feedback. For servo and induction motors, it is also important to ensure that the selected driver can handle the feedback from the motor. If the motor runs at a higher speed and the frequency converter cannot handle high frequencies, neither of the two components will accomplish the expected work.
Torque. In the new projects, in general, the first choice is to apply and select the motor to meet the mechanical and performance requirements; then, select the gearbox and transducer suitable for the motor, and the transducer defines the peak torque. If the output of the motor is greater than that required by the frequency converter, the system will withstand pressure and may damage the driver.
Selection specification adjustment software provided by some manufacturers can eliminate incompatibility problems and help optimize specific objectives.
It is very simple to determine peak torque, but when choosing the appropriate motor specifications, the root mean square (RMS) torque should also be calculated to take into account the variation of the required torque and the duration of each torque.
Programming and Regulation
For more dynamic, complex and high performance applications, ensuring that servo motors and servo drivers work together becomes more challenging. Open vector control requires motor characteristics, such as resistance ratings. Non-standard motor types may have specific requirements. Even the induction motor in the vector closed-loop servo control system can be accurately positioned by programming.
When engineers use different companies to match servo motors and servo drivers, they may encounter more difficult problems. Most manufacturers have at least documentation on which components are compatible with each other and which are incompatible, thus reducing the likelihood of mismatches. Choosing the same manufacturer can simplify the process from selection to commissioning, and accelerate the transformation and modernization upgrade.
Selection specification adjustment software provided by some manufacturers can eliminate incompatibility problems and help optimize specific objectives, such as reducing front-end costs or long-term energy conservation. Advances in system modeling mean being able to compare the performance of two products and understand how they will work in applications. Although they are usually based on computational rather than operational values, these models can provide accurate images in advance based on numerical values.
Wiring. If the servo motor and servo driver in use are provided by two vendors, something as simple as wiring will go wrong. Cables can be purchased from the motor or driver manufacturer, but the problem is that they are not necessarily standard parts for application running feedback and equipment. Even pins can be different.
When a problem is caused by a simple connection error, it is not always easy to find out. For induction motors, wiring errors may lead to reverse motion. However, when using servo motor, it is necessary to connect the phase correctly, otherwise the motion control system will not work. If the feedback wiring is incorrect, it may even cause permanent damage to the wiring components.