Energy Efficiency of AC Frequency Converters
AC frequency converters are important components of modern energy-saving technologies. However, the product manager of Mitsubishi Electric, Matt Handley, raises the question: how many of the existing basic electric drives are tuned for maximum efficiency?
Challenges for Designers and Engineers
In light of ongoing changes in legislation aimed at reducing energy consumption in industry, energy efficiency has become a critical issue for machinery designers, engineers, and financial directors. Numerous technologies have been developed to help businesses optimize their energy expenditures and reduce greenhouse gas emissions. However, are all these technologies being utilized to their maximum effectiveness?
Energy Consumption of Electric Motors
According to official statistics, electric motors consume 60% of all industrial electricity. Installing frequency converters to control motor speed can help save a significant amount of energy: the cost of such converters is typically recouped within 16-18 months.
It is also important to note that frequency converters allow for adjusting the power consumption of the motor to the minimum necessary level for specific operating conditions, opening up additional opportunities for energy savings.
Is Maximum Efficiency Achieved?
Today, thousands of converters are installed at various industrial sites, resulting in substantial savings on electricity costs. But are engineers getting the maximum return from frequency converters? It is important to understand whether maximum energy savings are being achieved during operation.
Many believe that installing a frequency converter means automatically achieving high energy savings; however, this is only part of the truth. Indeed, the electric drive can optimize motor speed according to operating conditions, but to achieve the best results during commissioning, it is necessary to properly configure the converter, activating the intelligent energy-saving mode.
Steps to Achieve Optimization
Where to start...
First, attention should be paid to the nature of the load (constant or variable torque). This will allow for setting the output power of the converter in accordance with the type of load and ensure maximum energy savings.
- In constant torque mode, the frequency converter reduces energy consumption, but maximum savings are achieved in the case of variable torque, especially for fans and pumps.
- Certain types of pumps may require setting for constant torque.
Special Energy-Saving Modes
Many frequency converters are also equipped with special energy-saving modes and algorithms that select optimal output parameters to achieve maximum efficiency.
For example, the FR-F800 from Mitsubishi Electric is designed for pumps, fans, and compressors and features energy-saving modes that provide savings of up to 15% compared to standard modes.
This frequency converter also offers additional functions that can be beneficial for industries working with fans, pumps, and compressors, ensuring increased performance along with energy savings.
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