Using EMI Filters in Industrial and Medical Applications
In today’s technology-driven world, electronics play a critical role. From smartphones to industrial machinery, the abundance of electronic devices has increased the need for effective electromagnetic interference (EMI) and electromagnetic compatibility (EMC) filtering. These filters ensure that electronic devices operate harmoniously without causing or being affected by unwanted electromagnetic emissions.
Applications of EMI Filters
Standalone EMI filters play a vital role in improving the performance and reliability of complex systems in the industrial and medical fields. Let’s take a closer look at some common applications in these fields.
1. Power Supplies and Power Systems: Power supplies must provide consistent, stable power in industrial and medical environments. EMI filters prevent grid disturbances from propagating to downstream devices that may not tolerate it, while ensuring that high-frequency energy generated by switch-mode power conversion does not propagate upstream to the grid, where it could interfere with other offline devices nearby. EMI filters in power systems are critical to eliminating noise that could cause disruptions in sensitive equipment, leading to errors or failures. For example, even minor power quality issues in precision manufacturing can lead to serious production defects.
2. Rotating Machines: The majority of the world’s electrical loads are made up of rotating machines. Pumps and motors are key components of most high-power devices, such as household appliances (such as air conditioners, refrigerators and washing machines) or industrial equipment (such as elevators, escalators, automated production machines) or laboratory instruments (such as centrifuges). EMI filters prevent premature wear caused by electrical noise, thereby extending the life of the equipment. In applications such as CNC machines or robotic arms, this means smoother operation and lower maintenance costs. Motors and pumps are also notorious for causing electrical noise in nearby equipment. This noise is often generated by the switching action of motor control circuits (such as those in variable frequency drives) and the commutation process of brushed motors. The rapid switching of current and voltage generates EMI in the form of conducted and radiated emissions.
3. Transmission Equipment: In industrial communication equipment, EMI filters are essential to maintain signal integrity. They ensure that the data transmitted between sensors, PLCs and control systems is accurate. This is particularly important in automated processes, where real-time data exchange is essential for coordination and efficiency.
4. Renewable Energy Systems: In renewable energy systems, power inverters and DC-DC converters are key to integrating solar or wind energy into the grid. Much like power supplies, the switch-mode power conversion networks in these devices can generate powerful electromagnetic fields that can manifest as both radiated and conducted emissions. These fields are generated by the high-speed switching action of transistors, which can produce rapid voltage and/or current discontinuities that contain various frequency components, including high-frequency harmonics, which can interfere with the operation of nearby electronic equipment.
5. Industrial Machinery: EMI filters in industrial machinery help ensure the integrity of the entire system. They help ensure that the electromagnetic noise generated by the machinery does not affect the accuracy of the control system or sensor readings. This is critical in precision machining or automated assembly, where even small errors can cause serious quality issues.
6. Medical Applications: Due to the critical nature of medical devices and the sensitivity of patients, medical environments introduce some unique risks and challenges in terms of EMI and EMC.
The following are product recommendations and comparisons of several TDK EMI filters for industrial and medical applications:
1. RSEN Series (Industrial Application)
Applications: Suitable for inverters, industrial control systems, and servo drives.
Features of RSEN Series:
High-efficiency filtering performance to cope with industrial environments with strong electromagnetic interference.
Wide operating temperature range (-25°C to 85°C) to meet the needs of harsh environments.
Compact design is suitable for space-constrained installation environments.
Typical parameters: Insertion loss: 50dB at 1MHz; UL/CSA/IEC certified to meet global industrial equipment standards.
2. B84143C Series (Industrial Three-Phase Filter)
Applications: Industrial robots, PLCs, three-phase motor control equipment.
Features of B84143C Series:
Designed for three-phase power supply systems, high-performance filtering capability significantly reduces harmonic interference.
Can be used for high-power devices, supporting a wide current range of 8A~36A.
Typical parameters: Insertion loss: 55dB at 100kHz; Large size, but high installation flexibility.
3. RSEV series (medical small equipment)
Applications: used in portable medical equipment or small electronic devices such as monitors and injection pumps.
Features of RSEV series:
Extremely low leakage current, meeting the strict requirements of portable medical equipment for electromagnetic interference.
Small design, easy to embed in compact medical products.
Typical parameters: Insertion loss: 60dB at 10MHz.
4. ZCAT3035-1330A (universal toroidal core filter)
Applications: cable interference suppression of communication equipment and industrial automation equipment.
Features of ZCAT3035-1330A:
No additional circuit design is required, just clip it on the cable for use.
Particularly suitable for emergency interference suppression or rapid verification environment.
Typical parameters: Insertion loss: 30dB at 10MHz.
Product Selection Recommendations
Industrial: It is recommended to choose RSEN or B84143C series, which are optimized for high power and harsh environments and suitable for industrial automation and motor control systems.
Medical: RSEV series are recommended, which meet the strict requirements of the medical industry for low leakage current and high reliability.
Emergency Suppression Needs: ZCAT3035-1330A can be considered, which is convenient for quickly solving interference problems and has a wide range of applications.
As an independent electronic distributor, ICHOME provides a variety of EMI filters from DC input to AC input for medical and industrial applications, including single-phase and three-phase inputs, including high-performance amorphous core filters.
