How to effectively resist the damage of high-frequency noise and harmonics to power electronic systems?

High-frequency noise and harmonics are two common harmful components in power electronic systems. High-frequency noise usually originates from the switching action of switching power supplies, the rapid switching of power electronic devices, etc. They exist in the power system in the form of high-frequency signals, with the characteristics of small amplitude and high frequency. Harmonics are generated by nonlinear loads (such as rectifiers, inverters, frequency converters, etc.). They exist as frequency components that are integer multiples of the fundamental frequency, which will cause more complex effects on the power system.

The impact of high-frequency noise and harmonics on power electronic systems is multifaceted. They will cause distortion of the power waveform, reduce the quality of the power supply, and fail to meet the load equipment's demand for stable and pure power. High-frequency noise and harmonics will generate additional losses and heat in the load equipment, causing the equipment to overheat and even cause failures. They may also interfere with the communication and control signals of the power electronic system, affecting the stability and reliability of the system.

In the face of the damage of high-frequency noise and harmonics to power electronic systems, the three-phase AC input reactor has become an important line of defense in the system with its unique low-pass filtering effect. Three-phase AC input reactors are usually composed of inductive elements, which have a blocking effect on AC, and their blocking effect is proportional to the rate of change of current. When high-frequency noise and harmonics try to pass through the reactor, they encounter a large impedance and are effectively attenuated. In contrast, for low-frequency components (such as fundamental waves), the blocking effect of the inductive element is small, allowing them to pass smoothly. Therefore, the three-phase AC input reactor essentially constitutes a low-pass filter, which can significantly reduce the interference of high-frequency noise and harmonics on the power electronic system.

The design of three-phase AC input reactors needs to consider multiple factors, including inductance, frequency response, loss, etc. The selection of inductance should be based on the specific needs of the system to ensure effective attenuation of high-frequency noise and harmonics. The frequency response of the reactor should be as flat as possible to reduce interference with useful signals. In order to reduce losses, the reactor usually adopts high-quality materials and optimized structural design. In addition, the three-phase AC input reactor also needs to consider the compatibility with other components in the system to ensure the overall performance of the system.

Three-phase AC input reactors are widely used in power electronic systems, including but not limited to industrial automation, power transmission and distribution, and new energy generation. In the field of industrial automation, three-phase AC input reactors are widely used in the input end of power electronic equipment such as inverters and servo drives, effectively reducing the interference of high-frequency noise and harmonics on the equipment, and improving the stability and reliability of the equipment. In the field of power transmission and distribution, three-phase AC input reactors are used to improve the power factor of the power system, reduce the impact of harmonics on the power grid, and improve the power supply quality of the power grid. In the field of new energy generation, three-phase AC input reactors are used in grid-connected inverters of renewable energy power generation systems such as wind power and photovoltaics, effectively reducing the pollution of harmonics on the power grid and improving the utilization rate of renewable energy.

The actual application effect of three-phase AC input reactors is remarkable. By reducing the interference of high-frequency noise and harmonics on power electronic systems, it improves the purity of the power waveform, reduces the loss and heat generation of load equipment, and extends the service life of the equipment. It also helps to improve the power factor of the power system, improve the power supply quality of the power grid, and provide a strong guarantee for the stable operation of the power electronic system.

With the continuous development of power electronics technology, three-phase AC input reactors are also constantly innovating and improving. On the one hand, the application of new materials and advanced manufacturing technologies has made the performance of reactors more superior, with lower losses and higher efficiency. On the other hand, the development of intelligent and digital technologies has enabled reactors to monitor the operating status of the system in real time and automatically adjust parameters such as inductance to meet the needs of different working conditions. In addition, the integrated design of three-phase AC input reactors and other power electronic components is also one of the important directions for future development.