Rising energy costs, a sense of environmental responsibility, government regulation, and a need for energy reliability are driving efforts for energy efficiency in manufacturing.
An inverter is an effective tool in conserving and recovering energy in motor systems.
A frequency inverter controls AC motor speed. The frequency inverter converts the fixed supply frequency (60 Hz) to a variable-frequency, variable-voltage output to enable precise motor speed control. Many frequency inverters even have the potential to return energy to the power grid through their regenerative capability.
Several Principles for Energy Saving of Frequency Inverter
There are certain conditions for the inverter to save power. Under the conditions that do not affect the use, after appropriately changing the working condition parameters, the energy consumed by the unreasonable operating parameters can be saved, and the general operation can be changed into economic operation.
To save energy, you must reduce the frequency. The more you drop value, the more power will be saved. In principle, the frequency inverter cannot save power without lowering the frequency.
It is related to the motor load rate. When the load ratio is 10% to 90%, the power saving rate is about 8% to 10% at mostly, and the load rate is low, and the corresponding power saving rate is higher. However, the reactive power saving rate is about 40% to 50%, which does not include electricity.
It is related to the reasonable degree of the operating parameter value of the original operation. For example, it is related to the adjustable magnitude of pressure, flow rate, and rotational speed. If the amount of adjustment is large, the power saving rate is high, otherwise it will be the opposite situation.
It is related to the adjustment method originally adopted. It is uneconomical to use the imported or exported valve method to adjust the operating parameters. If it is changed to the inverter speed regulation, it is economical and reasonable. After using the frequency inverter to adjust the operating method, it can save 20%~30% of power saving than the manual valve.
It is related to the original speed control method. For example, the speed control of the slip motor was originally used, because the speed regulation efficiency is low, especially at medium and low speeds, the efficiency is only 50% or less, which is very uneconomical. After changing the speed of the frequency inverter, this part of the electric energy is saved. At present, most of the industries such as light industry, textile, paper, printing and dyeing, plastics, rubber, etc. They still use slip motor, then using frequency inverters to achieve energy saving, technical transformation work is a matter of urgency.
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.
It is related to the length of time the motor use. For example, the motor works 24 hours a day, 365 days a year, the power saving is large, and vice versa.
It is related to the power of the motor itself. Under the same power saving rate, the higher power motor, the more power saving, and the economic benefit is large. Even if the power saving rate is lower than that of the small power motor, the actual income is large.
It is related to the importance of the production process of the unit. First of all, it is necessary to select a product with high power consumption, high product cost, and the current speed control method is not economical and reasonable, and each of them can be retrofitted, and the inverter can be used immediately and with half the effort.
When choosing the frequency inverters for speed regulation or energy saving, the above 10 principles should be observed as a prerequisite for the decision. If the local electricity price is high, the economic benefits will be even greater when the electricity is saved. This is something that must be considered.