What is frequency resolution?

Frequency resolution is an important concept in digital control inverter when adjusting the frequency, it refers to the smallest unit of frequency change of the inverter output frequency, that is, the precision or level difference of frequency adjustment.

In a digitally controlled inverter, even if the frequency command is an analog signal, the output frequency is also given in levels, and the smallest unit of this level difference is the frequency resolution.

I.Influence of frequency conversion resolution

1. Control accuracy: the frequency resolution directly determines the control accuracy of the frequency converter. When the frequency conversion resolution is small, the output frequency of the frequency converter can more accurately approximate the required frequency value, thus improving the control accuracy of the system.
2. Response speed: Although the frequency conversion resolution has a relatively small impact on the response speed of the frequency converter, but in some high-precision, high-response speed applications, it is still very important to choose the appropriate frequency conversion resolution.

II.Value range of frequency conversion resolution

Frequency conversion resolution usually takes the value of 0.015-0.5 Hz.

For example, the resolution is 0.5 Hz, then the top of 23 Hz can be changed to 23.5, 24.0 Hz, and therefore the motor action is also a graded follow.

This causes problems for applications such as continuous winding control. In this case, if the resolution is about 0.015 Hz, it is possible to adapt to a 4-stage motor with a step difference of 1 r/min or less.

In addition, some models have a different resolution between the given resolution and the output resolution.

III.What is the relationship between the output frequency of the inverter and the inverter resolution?

1.Smoothness: High-resolution frequency converter can provide smoother frequency change, which makes the motor run more smoothly and reduces the mechanical shock and noise caused by the sudden change of frequency.

2.Adaptability: for some processes that require very fine control, such as precision positioning, continuous winding control, etc., high-resolution frequency converter can better adapt to these requirements, to provide more appropriate control effect.

3.Energy consumption: In some applications, such as speed regulation of fans and pumps, high-resolution inverters are able to control energy consumption more accurately because they can work with smaller frequency variations, resulting in more efficient energy utilization.

4.Cost: Typically, the higher the resolution of the inverter, the higher its cost. Therefore, when designing and selecting a frequency converter, you need to balance resolution and cost according to the actual application requirements and budget.