The Confession of a Frequency Converter
My name is frequency converter. Among many energy-saving new products, I am known as the "energy-saving pioneer" because of my excellent performance.
In today's world, extreme weather events occur frequently: melting glaciers, rising sea levels, persistent droughts, and devastating torrential rains... all seriously threatening human survival. Today, energy conservation, emission reduction, and environmental protection have become crucial issues that humanity must collectively address. I was born in this context.
A frequency converter , as the name suggests, is a component that integrates frequency conversion technology and microelectronics technology to change the frequency and amplitude of the power supply to a motor, thereby controlling the electric drive of an AC motor. My creation embodies the wisdom and hard work of humankind.
To ensure the safe and reliable operation of equipment such as fans and pumps, engineers incorporate a certain margin of safety when designing power drives. When a motor is not running at full load, the excess torque increases active power consumption, resulting in wasted energy. For example, if it takes one and a half horses to pull a load of goods up a hill, people usually choose two horses to complete the task. Isn't half a horse still not being used? Clearly, matching the load to the horse's carrying capacity can reduce waste and maximize efficiency. The same principle can be applied to the margin of safety in power drives. If the motor speed can meet the real-time requirements, then the energy loss of the system will naturally be reduced!
To achieve effective control of electric drive devices, scientists have made bold innovations. In 1967, the world's first frequency converter was successfully developed and put into commercial operation. After more than forty years of development, AC motor frequency conversion speed regulation has become a major means of saving energy, improving production processes, enhancing product quality, and improving the operating environment. Correspondingly, our frequency converters are widely favored by users for their high efficiency, high power factor, and excellent speed regulation and starting/braking performance, playing an important role in many fields.
First, there's the soft-start function. Hard starting of a motor often involves a starting current 3-5 times its rated current. This sudden increase in current not only complicates motor design and manufacturing but also severely impacts the power grid capacity and transmission/distribution infrastructure, causing significant damage to baffles, valves, and other equipment. My function is to change the frequency and amplitude of the AC motor's power supply, thereby altering the period of its magnetic field and achieving smooth motor speed control. This allows the motor's starting current to gradually increase from zero, with the maximum value never exceeding the rated current. This reduces the impact on the power grid and the demand on power supply capacity, extending the equipment's lifespan.
Secondly, optimizing motor operation is crucial. In systems like fans and central air conditioning, traditional water supply methods utilize water towers, elevated water tanks, and pressure tanks. The outlet water pressure is frequently affected by factors such as tank height and water volume, making constant pressure difficult to achieve. Furthermore, traditional speed control methods for fans and pumps rely on adjusting the opening of inlet and outlet baffles and valves to regulate airflow and water supply. When the input power is excessive, a large amount of energy is wasted in the baffle and valve throttling process. This is akin to transporting far more bricks than needed to a high-rise building without accurate calculations, resulting in wasted manpower and time. Today, engineers combine frequency converters, PID controllers, microcontrollers, and PLCs to form a control system that can regulate the pump's output flow, reducing unnecessary labor. By simply setting the outlet pressure of the main water supply pipe, comparing the set value with the actual feedback value, and processing the difference, the system issues control commands to regulate the number and speed of the pump motors, thereby achieving a constant pressure in the main water supply pipe. Compared to controlling water pressure with regulating valves, this system reduces pipe resistance, significantly minimizes flow losses, and eliminates the need for frequent manual operation, thus reducing labor intensity. Today, I can be seen busily working in waterworks, residential communities, fire-fighting water supply systems, sewage lifting and treatment systems, agricultural irrigation and drainage, and musical fountains.
We also demonstrate impressive performance in central air conditioning and fan systems. Central air conditioning systems are designed based on the maximum required cooling (heating) capacity plus 10-20%, resulting in high power consumption but also significant energy-saving potential. By using our technology to regulate the speed and energy efficiency of central air conditioning compressors, chilled water pumps, cooling pumps, cooling tower fans, and return air devices, we can avoid excessive flow and pressure, ensuring the system's normal and effective operation and saving 20%-50% on electricity. For example, during the construction of the "First Tunnel Across the Yangtze River"—the Shanghai Yangtze River Tunnel—builders needed to ensure good ventilation within the approximately 8.9-kilometer-long tunnel with an inner diameter of 13.7 meters. To achieve this, the project adopted Delixi frequency converters, directly setting the motor speed according to the air volume demand, precisely adjusting the airflow, optimizing the use of electrical facilities, and achieving energy savings of 20%-45%.
While generating economic benefits, frequency converters also have significant social benefits. It is estimated that the frequency converters produced and installed by ABB Group alone can save 115 billion kilowatt-hours of electricity annually, correspondingly reducing carbon dioxide emissions by 97 million tons, which is more than Finland's annual carbon dioxide emissions.
Thirdly, it has system protection functions. After detecting abnormal states in the system, it can automatically correct actions or block the PWM control signals of power semiconductor devices to automatically stop the motor, such as overcurrent stall prevention, overcurrent cut-off, semiconductor cooling fan overheating protection, and instantaneous power outage protection.
After hearing my confession, you will think I am a true "energy-saving pioneer". So please give me the opportunity to make full use of my abilities in production and daily life!
