When selecting a frequency converter for speed regulation or energy saving, the following 8 principles should be followed as a prerequisite for the decision. If the local electricity price is high, the economic benefits will be greater when the same amount of electricity is saved, which is also an inevitable consideration.
1: There are certain conditions for the inverter to save power. Under the condition that does not affect the use, after appropriately changing the working condition parameters, the electric energy consumed by the unreasonable operating parameters can be saved, and the general operation can be converted into economic operation.
2: To save energy, the frequency must be reduced. The larger the drop value, the more power saving. Without reducing the frequency, the frequency converter cannot save power in principle.
3: Related to the motor load rate. When the load rate is 10% to 90%, the power saving rate is at most about 8% to 10%, and a lower load rate corresponds to a higher power saving rate. However, the reactive power saving rate is about 40% to 50%, excluding electricity costs.
4: It is related to the reasonable degree of the original working condition parameter value. For example, it is related to the adjustable values ??such as pressure, flow, and speed. If the adjustable amount is large, the power saving rate is high, otherwise the opposite is true.
5: It is related to the original adjustment method. It is very uneconomical to use imported or exported valves to adjust the operating parameters. If it is changed to frequency converter for speed regulation, it is economically reasonable. After using the frequency converter to adjust the speed, it can save 20% to 30% more electricity than adjusting the operation method with manual valves.
6: It is related to the original speed adjustment method. For example, the original use of slip motor speed regulation, because the speed regulation efficiency is low, especially in the middle and low speed, the efficiency is only below 50%, which is very uneconomical. After changing to the frequency converter for speed regulation, this part of the energy is saved. At present, most industries such as light industry, textile, papermaking, printing and dyeing, plastics, rubber, etc. still use slip motors, so the use of frequency converters to achieve energy saving, technical transformation is a top priority.
7: It is related to the working mode of the motor. For example, the power saving of continuous operation, short-time operation, and intermittent operation are different.
8: It is related to the length of time the motor starts. For example, if you turn on the phone 24 hours a day, the power saving for 365 days a year is large, and vice versa.