APF solve five major problems in the application of frequency converters.

With the development of industry, previously, ordinary asynchronous motors were mostly designed for constant frequency and constant voltage. They could no longer fully meet the requirements of variable frequency speed regulation, which has affected the production development of enterprises. After research, it was found that active power filters can solve the impact that variable frequency inverters have on motors during application.

1. Solving the problems of reduced efficiency and increased temperature of the motor:

Regardless of the type of frequency converter, during operation, it generates varying degrees of harmonic voltage and current, causing the motor to operate under non-sinusoidal voltage and current. Since the asynchronous motor rotates at a speed close to the synchronous speed corresponding to the fundamental frequency, when high-order harmonic voltage is cut across the rotor bars with a large slip, significant rotor losses will occur. In addition, the additional copper loss due to the skin effect must also be considered. These losses will cause the motor to generate additional heat, reduce efficiency, and decrease output power. For example, when a common three-phase asynchronous motor operates under the non-sinusoidal power supply provided by the frequency converter, its temperature rise generally increases by 10% to 20%.

2. Address the issue of reduced insulation strength of the motor and accelerated aging.

3. Address the issues of increased harmonic electromagnetic noise and vibration;

4. Address the adaptability of the motor to frequent starting and braking operations

Due to the use of frequency converters for power supply, the motor can start at very low frequencies and voltages without any impact current, and can also use various braking methods provided by the frequency converter for rapid braking. This creates conditions for frequent starting and braking. As a result, the mechanical system and electromagnetic system of the motor are subjected to cyclic alternating forces, which causes fatigue and accelerated aging problems for the mechanical structure and insulation structure.

5. Address the issue of the inverter generating high odd harmonics

Among them, the 5th and 7th harmonics have the greatest impact on the frequency converter and the motor. Usually, in the design process, to reduce the influence of harmonics, reactors, capacitors for absorption, etc. are added; or a filter can be added at the output end of the frequency converter.

Jinneng Electric power technology Hubei Co.,Ltd was founded in 2011, located in Xiaogan City, Hubei Province, currently covers an area of more than 27,000 square meters, construction area more than 33,000 square meters, and we have 28 engineers with strong R&D capabilities,and had passed ISO9001, ISO14001, OHS18001, CCC, CQC, CE and other certifications.

Main products:
1. High and low voltage complete equipment: box-type substation, high and low voltage switchgear, cable branch box, photovoltaic products, circuit breakers, etc.
2. Cable accessories series: cold shrink cable accessories, heat shrink cable accessories, terminal connectors, direct insertion arrester and other electrical products;
3. Electrical components: capacitors, reactance, controllers, contactors, switches, meters, active filter devices, compensation devices, distribution boxes, and reactive power compensation and harmonic control.
Application: The products have been widely used in power grid, electric power, photovoltaic, communication, chemical, machinery, smelting, oil fields, factories, charging piles, railway stations, hospitals, schools, real estate, commercial centers and so on.
Cooperative customers: State Grid, China National Energy Construction, China Nuclear Photovoltaic, China Railway, Hong Kong Metro, etc.