The calculation method of the electronic gear ratio of the servo drive is mainly based on the resolution of the servo motor encoder and the pulse frequency and number of pulses output by the controller (such as PLC or host computer). The following is a detailed description of the calculation method:
1. Determine the encoder resolution
The encoder resolution is the number of pulses that the encoder can generate per rotation, usually expressed as pulses/revolution (P/r). This is the basic parameter for calculating the electronic gear ratio.
2. Determine the controller output parameters
You need to know the number of pulses that the controller can output per second, as well as the number of motor movements expected per second (such as the number of rotations or the number of linear movement distances).
3. Calculate the electronic gear ratio
The calculation formula of the electronic gear ratio is generally:
\[
\text{Electronic gear ratio} = \frac{\text{Number of pulses per second of the controller}}{\text{Number of pulses per revolution of the encoder} \times \text{Number of movements per second}}
\]
However, in actual applications, in order to simplify the calculation and make the numerator and denominator both integers (or easy-to-handle values), the electronic gear ratio may be adjusted by directly setting the numerator (gear ratio numerator) and denominator (gear ratio denominator) instead of directly calculating it through the above formula. This setting method is very common in the parameter configuration of servo drives.
4. Notes
* Matching pulse frequency: When setting the electronic gear ratio, it is necessary to consider the matching between the pulse frequency of the encoder feedback and the maximum pulse frequency output by the controller (such as PLC) to avoid signal loss or processing delay.
* System performance and stability: It is recommended to set the system's electronic gear ratio to close to 1:1 to avoid a large disparity between the numerator and denominator, thereby improving the system's performance and stability.
* Testing and debugging: After setting the electronic gear ratio, sufficient testing and debugging should be performed to ensure that the system operates normally and meets application requirements.
5. Example
Assume that the encoder resolution is 10,000 pulses/turn, the controller outputs 50,000 pulses per second, and the motor is expected to rotate 5 times per second. If calculated according to the above formula, the electronic gear ratio will be:
\[
\text{electronic gear ratio} = \frac{50000}{10000 \times 5} = 1
\]
However, in actual applications, the gear ratio numerator may be set to 1000 (or any value that matches the denominator) and the denominator may be set to 1000 (or other values that match the numerator) directly through the parameter setting interface of the servo drive to achieve a similar amplification effect, without having to strictly follow the calculation results of the above formula.
In short, the calculation method of the servo drive electronic gear ratio mainly depends on the resolution of the encoder and the output parameters of the controller, but in actual applications, it may be adjusted by directly setting the numerator and denominator.