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Permalloy is a nickel-iron alloy with high magnetic permeability, which is usually used to make magnetic shielding materials. The magnetic shielding performance of Permalloy is related to its thickness, alloy composition and magnetic field frequency. Generally speaking, increasing the thickness of Permalloy can improve its magnetic shielding effect, but the specific strength of the shielding magnetic field should also consider the following factors:   1. Thickness: The thicker the Permalloy is, the better the shielding effect. The thickness of Permalloy sheets usually used for shielding ranges from 0.1 mm to several millimeters.   2. Magnetic permeability: The higher the magnetic permeability of Permalloy, the better the shielding effect. The magnetic permeability of Permalloy can reach several thousand or even higher.   3. Magnetic field strength: The shielding effect is related to the strength of the external magnetic field. In weak magnetic fields, Permalloy has a better shielding effect, but in strong magnetic fields, its shielding effect may be weakened.   4. Frequency: Permalloy has a good shielding effect on low-frequency magnetic fields (such as DC magnetic fields and power frequency magnetic fields), but a relatively poor shielding effect on high-frequency magnetic fields.   The calculation of the specific shielding magnetic field strength needs to take these factors into consideration, and may require experiments to determine the best shielding effect. If there are specific application scenarios or parameters, more detailed information can be provided to obtain more accurate calculations or suggestions.

Have you ever wondered how modern electronic devices get energy from weak electrical signals? The answer is often related to an inconspicuous but crucial component - the power extraction coil. How does this small coil play a key role in the vast network of science and technology? What impact does it have on our lives? Today, we will explore in detail the principles, applications and importance of power extraction coils in modern technology.   1. Basic principles of power extraction coils   1.1 What is a power extraction coil?   It is a device that uses the principle of electromagnetic induction to obtain electrical energy. It is usually composed of a coil wound with one or more wires. When the external magnetic field changes, an electromotive force is induced in the coil to generate current. This process is called electromagnetic induction and is a direct application of Faraday's law of electromagnetic induction.   1.2 Working principle   The working principle is based on Faraday's law of electromagnetic induction, which states that changes in magnetic flux passing through a coil will generate an electromotive force (i.e. voltage) in a conductor. Specifically, when the strength or direction of a magnetic field changes, the electrons in the coil are moved by force, forming a current.   This phenomenon is widely used in modern electrical equipment. For example, in wireless charging devices, the transmitter generates an alternating magnetic field through a coil, and the power extraction coil at the receiving end senses the change in this magnetic field, thereby generating current to charge the device.   2. Historical development of power extraction coils   2.1 Early development   The history of power extraction coils can be traced back to the 19th century. At that time, Michael Faraday and Joseph Henry discovered the phenomenon of electromagnetic induction. Faraday verified through experiments that changes in magnetic flux can generate current in a closed circuit, which laid the foundation for the design and application of modern power extraction coils.   2.2 Technological progress   With the development of electromagnetic theory, the design and manufacturing technology of power extraction coils are also constantly improving. In the early 20th century, power extraction coils began to be widely used in motors and generators for energy conversion and transmission. With the advancement of materials science and manufacturing processes, the efficiency and stability of power extraction coils have been significantly improved.   In modern times, power extraction coils are not only used in traditional power equipment, but also widely used in radio technology, sensors, medical equipment and other fields, becoming an indispensable part of modern science and technology.   3. Diversified Applications   3.1 Wireless Charging   Wireless charging is one of the most common applications of power extraction coils. Through the principle of electromagnetic induction, the power extration coil can transfer the power from the transmitter to the receiver, thereby charging various devices. This technology is widely used in devices such as smartphones, electric toothbrushes, and wireless headphones, greatly improving the convenience of use.   3.2 RFID Technology   Radio Frequency Identification (RFID) technology is also one of the important applications of power extraction coils. In the RFID system, the reader communicates with the tag through an electromagnetic field. The power extration coil in the tag generates current after inducing the electromagnetic field, and then starts the circuit in the tag for data exchange. This technology is widely used in logistics management, identity recognition, asset tracking and other fields.   3.3 Medical Equipment   In medical equipment, power extraction coils also play an important role. For example, in implantable medical devices (such as pacemakers), power extraction coils can obtain energy from the outside wirelessly, thereby extending the service life of the device and reducing the surgical risks of patients.   3.4 Sensor Technology   power extraction coils are also widely used in various sensors. By sensing changes in the external magnetic field, the power extration coil can be used to detect and measure a variety of physical quantities, such as current, voltage, speed, position, etc. These sensors are widely used in industrial automation, vehicle monitoring, environmental monitoring and other fields, greatly improving the intelligence and automation level of the system.   IV. Advantages and Disadvantages   4.1 Advantages   Power extraction coils have many significant advantages. First, they can achieve contactless energy transmission, greatly improving the convenience and safety of the equipment. Second, the design and manufacture of power extraction coils are relatively simple, low cost, and easy to mass produce and apply. In addition, the power extration coil has high efficiency and reliability and can work stably in various harsh environments.   4.2 Disadvantages   However, the power extration coil also faces some challenges. First, the electromagnetic induction efficiency is subject to the design and material selection of the coil, and how to further improve the efficiency is an important topic. Second, the power extration coil may be subject to electromagnetic interference in the application, affecting its normal operation. Finally, with the rapid development of wireless charging and sensor technology, how to meet the growing performance requirements is also an urgent problem to be solved.

Permalloy has a certain application in audio transformers due to its high magnetic permeability and low coercivity. The impact of using Permalloy as the core material of the transformer on the sound quality is mainly reflected in the following aspects:   Low hysteresis loss: The low coercivity of Permalloy means that its hysteresis loss is very low. This can reduce the distortion of the audio signal during transmission, thereby improving the clarity and fidelity of the sound quality.   High magnetic permeability: High magnetic permeability allows the transformer to operate at a lower magnetic field strength, which helps to reduce core loss and transformer self-noise, thereby improving the sound quality. Wide frequency response: Due to the characteristics of Permalloy, the transformer can work effectively over a wide frequency range. This is especially important for audio applications because it is better able to transmit high-frequency and low-frequency signals, providing a smoother and more accurate audio response.   Low distortion: Permalloy transformers are generally able to maintain low harmonic distortion when transmitting audio signals, which has a positive impact on the overall sound quality of audio equipment. However, Permalloy transformers also have some limitations:   Cost: Permalloy is relatively expensive, which makes transformers using this material more expensive.   Saturation flux density: Permalloy has a lower saturation flux density, which means that in high-power applications, the transformer may enter saturation earlier, affecting the sound quality. In general, Permalloy transformers have significant advantages in sound quality, especially in high-fidelity audio equipment. However, its cost and limitations in high-power applications need to be considered in the design.

1. The Nature of Current Transformers   Current transformers are basic devices in power systems that excel at converting high currents into corresponding lower currents. They are essential in both measurement and protection applications in power systems. Their key role is energy conversion, converting high input currents into manageable low output currents that are proportional to the original current.   2. Working Principle of Current Transformers   The working principle of current transformers depends on Faraday's law of electromagnetic induction. The high current flowing through the primary coil of the transformer generates a magnetic field, which in turn induces a current in the transformer core. This induced current is then converted into the secondary coil current.   3. Identifying Errors in Current Transformers   1. Ratio Error   A common error in current transformers is ratio error. This occurs when the transformer cannot accurately convert current according to a predefined ratio. Typically, nonlinear characteristics of the magnetic core and changes in coil impedance cause this error.   2. Phase Error   Phase error is another type of error defined by the phase angle difference between the transformer output and input currents. This difference can seriously affect the operation and protection mechanisms of the power system.   4. Interpretation of factors affecting current transformer errors   1. Coil impedance   Coil impedance has an important impact on current transformer accuracy. Increased impedance leads to a decrease in output current, which causes ratio errors.   2. Core saturation   Core saturation significantly affects transformer performance. Once the core reaches saturation, the performance of the transformer drops sharply, resulting in potential ratio and phase errors.   3. Frequency   The frequency of the input current affects the performance of the current transformer. Any fluctuation in frequency causes changes in impedance, which changes the accuracy of the transformer.   4. Temperature   Temperature changes affect the performance of the current transformer. As the temperature increases, the resistance of the coil increases, resulting in ratio and phase errors.   5. Loading   Changes in load can have a negative impact on transformer performance. An increase in load may increase the error range of the transformer.   6. Insulation   Insulation performance is critical to the accuracy of the current transformer. Damage to insulation may introduce errors within the current transformer.   7. Manufacturing process   The manufacturing process of the current transformer also determines its performance. Advances and improvements in these processes can significantly reduce the error of current transformers.   V. Reduce current transformer errors   1. Choose the right current transformer   The first step to reduce transformer errors is to choose the right current transformer. It should have excellent performance and sufficient capacity to meet the needs of the power system.   2. Follow the installation and use guidelines   When installing and using current transformers, ensure that the integrity of the insulation is maintained, avoid high temperatures, and regularly inspect and maintain them to maintain their performance and accuracy.   3. In summary   Understanding the various factors that affect current transformer errors is essential to properly utilize current transformers and improve the efficiency and safety of power systems. By understanding these factors, we can effectively reduce or avoid current transformer errors.   FAQ   What does the ratio error of a current transformer mean?   Ratio error occurs when a current transformer fails to accurately convert current according to a predetermined ratio.   What are the key factors that affect current transformer errors?   The main factors include coil impedance, core saturation, frequency, temperature, load, insulation, and manufacturing process.   How can we minimize the error of current transformer?   Reducing the error can be achieved mainly by selecting the right transformer, installing and using it correctly, and maintaining it regularly.   How does the error of current transformer affect the power system?   The error of current transformer mainly affects the measurement and protection mechanism of the power system. Both ratio and phase errors can lead to unstable operation of the power system, which may cause accidents.   What is the working principle of current transformer?   The current transformer works according to Faraday's law of electromagnetic induction. When a large current flows through the primary coil, a magnetic field is generated, which induces a current in the core of the transformer. This induced current is then converted into auxiliary coil current.

Permalloy and silicon steel sheet are two different materials with some differences in properties and uses.   1. Permalloy: Permalloy is an alloy material with high strength, high corrosion resistance and high temperature stability.   It is mainly composed of nickel, chromium, phosphorus, boron and other elements, and is widely used in aerospace, chemical industry and manufacturing industries.   Permalloy has excellent mechanical properties and corrosion resistance, and can work stably for a long time in high temperature and corrosive environment.   2. Silicon steel sheet: Silicon steel sheet is a widely used electrical cold-rolled steel, which is characterized by a high silicon content.   Silicon steel sheet is mainly used to make core components of electrical equipment such as motors and transformers, with low magnetic permeability, low magnetic loss and high magnetic saturation induction intensity.   By adding an appropriate amount of silicon, the eddy current loss in the magnetic field can be effectively reduced and the conversion efficiency of the transformer can be improved.   When considering the magnetic conductivity, Permalloy (usually refers to nickel-iron soft magnetic alloy containing molybdenum, such as Permalloy) and silicon steel sheets each have their own characteristics and application fields:   The magnetic permeability of this material is very high, which can reach hundreds of thousands, so it is very suitable for applications that require extremely high magnetic permeability and low hysteresis loss, such as transformers, shielding materials, read-write heads, etc.   Silicon steel sheet:   Silicon steel sheet is a kind of steel containing a certain proportion of silicon, which is usually used in electrical applications, such as core materials for motors, generators and transformers.   The magnetic permeability of silicon steel sheet is low, usually between thousands and tens of thousands, but its advantages are low cost and good mechanical strength and heat resistance.   Silicon steel is mainly used to manufacture the core of high-power equipment, and its silicon content can effectively reduce the eddy current loss and hysteresis loss of the core.   Therefore, Permalloy and silicon steel sheet are two different materials with different application fields and performance characteristics.

I would like to ask about Permalloy:   1. Can Permalloy be used as the core of a 30kHZ transformer?   2. Can Permalloy be milled? I hope you can help answer this question! Permalloy is a metal alloy material with very low resistivity and drastically increased high-frequency loss. It can generally only be used in the low-frequency range.   At the frequency of 30khz, it is recommended to use manganese-zinc ferrite material, which is still cheap.   Permalloy is generally a strip material, most of which are wound or laminated, and generally do not require milling.   Permalloy of conventional thickness cannot meet the working requirements at a frequency of 30kHz. Ultra-thin strips with a thickness of less than 0.05 are required to have a chance.   Permalloy can be made into strips and rods. Rod materials can be milled, but because Permalloy is soft, it has high requirements for milling tools.

Permalloy cores are designed for use in a variety of power applications, and one of the key performance characteristics is its high temperature stability. This means that it is able to maintain good magnetic properties, including high permeability and low energy loss, at higher temperatures. This high temperature resistance makes Permalloy cores ideal for use in power equipment that needs to withstand high temperature environments for a long time, such as certain types of transformers, motors, and power electronic equipment.   Permalloy's high temperature resistance is due to its special alloy composition and microstructure, which are carefully selected and optimized during the design and production of the alloy. The specific ratios of elements such as iron, silicon, aluminum, and nickel, as well as the microstructure obtained through a precise heat treatment process, work together to improve its performance stability at high temperatures.   Although Permalloy cores do have good high temperature resistance characteristics, their performance is still affected to some extent at extreme temperatures. Increased temperature causes the material's magnetic permeability to decrease and energy loss to increase, although this effect is much smaller in Permalloy than in other materials. Therefore, when designing and using power equipment containing Permalloy cores, it is very important to consider its operating temperature range and stability.

For the split current transformer installed in outdoor overhead lines or cable trenches, the cut surface of the transformer will be exposed to the air and will be exposed to rain or soaked in water in the cable trench, which will cause rust and affect the product performance. Water accumulation in the secondary terminal will also cause short circuit, so measures need to be taken to prevent rain or water immersion. Based on our many years of practical experience in manufacturing split current transformers, there are currently two solutions that can be used, which are briefly introduced as follows:   The first solution is to bury the secondary wire directly into the resin casting body (the wire uses a three-proof silicone wire) to prevent short circuits in the secondary terminal, and add a waterproof silicone ring to the cut surface for sealing and waterproofing. This solution has good protection for the secondary end and the cut surface, and can be widely used in all rain and water immersion occasions. In addition, because the base cannot be fixed in the cable trench, the base installation method is not used. The inner hole with a rubber plug is fixed on the cable. This installation method is shown in the figure below. The second solution is the "open type current transformer + silicone rubber sleeve" solution, which is also used by customers for installation on low-voltage outdoor lines. However, this method can only prevent light rain and cannot prevent immersion in water, so it cannot be used for installation in places where water may accumulate, such as cable trenches. This solution is limited by the specifications of the silicone rubber sleeve and the inner diameter of the transformer can only be 50mm. The actual product is shown in the following photos:

Among many advanced materials, 1J85 Permalloy has received special attention for its excellent magnetic properties and wide application. However, where does the particularity of this material come from? What are the unique features of its composition, performance and application fields? This article will explore 1J85 Permalloy in depth and take you to find out.   1. Composition analysis of 1J85 Permalloy   1J85 Permalloy, as a soft magnetic alloy, is mainly composed of elements such as nickel, iron, and molybdenum. This specific alloy ratio gives it unique physical and chemical properties. Specifically, 1J85 alloy contains approximately 80% nickel (Ni), 15% iron (Fe), and approximately 5% molybdenum (Mo). This unique composition configuration makes 1J85 alloy perform well in magnetic properties, mechanical properties, and electrical properties.   2. Performance advantages of 1J85 Permalloy   1. High magnetic permeability One of the biggest features of 1J85 Permalloy is its high magnetic permeability. This property enables it to effectively conduct magnetism in a magnetic field, thus playing an important role in various electromagnetic applications.   2. Low coercivity Coercivity refers to the reverse magnetic field strength required to eliminate the magnetization state of a material after it is magnetized. 1J85 alloy has a low coercivity, which means that it can be quickly magnetized and demagnetized under a small magnetic field, greatly improving the response speed and efficiency of electromagnetic equipment.   3. Good temperature stability 1J85 alloy can keep its magnetic properties basically unchanged over a wide temperature range, which makes it suitable for electronic equipment and electromagnetic systems that need to work under different temperature conditions.   IV. Expansion of application areas   1. Transformers and inductors 1J85 Permalloy is widely used in power transformers and inductors. In these applications, the high magnetic permeability and low loss characteristics of the alloy can effectively improve the energy efficiency and performance of the equipment.   2. Electromagnetic shielding Due to the high magnetic permeability of 1J85 alloy, it is also often used as an electromagnetic shielding material to reduce electromagnetic interference between electronic equipment and ensure the normal operation of the equipment.   3. Precision sensors The high sensitivity and good temperature stability of 1J85 alloy make it an ideal material for manufacturing various precision sensors, such as magnetic sensors, position sensors, etc.

Main performance of split core current transformer:   Split core current transformer mainly cooperates with relay device. When short circuit, overload and other faults occur in the line, it provides signal to relay device to cut off the fault circuit to protect the safety of power supply system. The working conditions of protective micro current transformer are completely different from those of measuring transformer. The protective transformer only starts to work when the current is several times or dozens of times larger than the normal current. Main requirements of protective transformer: 1. Reliable insulation, 2. Sufficiently large accuracy limit coefficient, 3. Sufficient thermal stability and dynamic stability.   Split core current transformer can meet the accuracy level requirements under rated load. The large primary current is called rated accurate limit primary current. The accuracy limit coefficient is the ratio of rated accurate limit primary current to rated primary current. When the primary current is large enough, the core will be saturated and cannot reflect the primary current. The accuracy limit coefficient represents this characteristic. Accuracy level of protective transformer 5P, 10P   Split core current transformer function The transformer for power system is a special transformer that transmits the information of high voltage and large current of the power grid to the metering, measuring instruments, relay protection and automatic devices on the low voltage and small current secondary side. It is a contact element between the primary system and the secondary system. Its primary winding is connected to the power grid, and the secondary winding is connected to the measuring instrument, protection device, etc. The transformer cooperates with the measuring instrument and metering device to measure the voltage, current and electric energy of the primary system; cooperates with the relay protection and automatic device to form electrical protection and automatic control of various faults in the power grid. The performance of the transformer directly affects the accuracy of the measurement and metering of the power system and the reliability of the action of the relay protection device.  

Permalloy usually refers to an iron-nickel alloy with a nickel content in the range of 30~90%. It is a widely used soft magnetic alloy.   Through appropriate processes, magnetic properties can be effectively controlled, such as an initial magnetic permeability of more than 105, a large magnetic permeability of more than 106, a coercive force as low as 2‰ Oersted, and a rectangular coefficient close to 1 or close to 0. Permalloy with a face-centered cubic crystal structure has good plasticity and can be processed into 1μm ultra-thin strips and various usage forms. Commonly used alloys include 1J50, 1J79, 1J85, etc. The saturation magnetic induction intensity of 1J50 is slightly lower than that of silicon steel, but the magnetic permeability is dozens of times higher than that of silicon steel, and the iron loss is 2~3 times lower than that of silicon steel.   It is made into a transformer with a higher frequency (400~8000Hz) and a small no-load current, which is suitable for making small high-frequency transformers below 100W. 1J79 has good comprehensive performance and is suitable for high-frequency low-voltage transformers, leakage protection switch cores, common-mode inductor cores and current transformer cores. The initial magnetic permeability of 1J85 can reach more than 100,000 105, which is suitable for low-frequency or high-frequency input and output transformers, common-mode inductors and high-precision current transformers for weak signals.

No matter what type of rod-shaped inductor coil, it is inevitable that it will heat up during use! Heating is a normal phenomenon, but if the heating is too large, it may not be a normal phenomenon.   In fact, the solution to inductor heating is essentially the same even for different inductor types. It needs to be solemnly explained: the function of the rod-shaped inductor coil is to store energy, suppress electromagnetic interference, pass DC and block AC. When the current flowing through the inductor coil is large, the coil will heat up. In severe cases, it will get hot, the inductance of the inductor will decay, and the surface temperature of the inductor body will rise. When the temperature rise current exceeds 40 degrees Celsius, the inductor will lose its inductance characteristics. In severe cases, the entire PCB board will be burned. According to the experience summary of the case, the common reasons for the heating of the rod-shaped inductor coil are mainly the following:   1. If the abnormal heating of the magnetic rod coil inductor is caused by improper use of the equipment, this only needs to adjust the use method and use it correctly according to the specifications. In fact, it can be solved.   2. If the abnormal heating is caused by the quality problem of the magnetic rod coil inductor:   The treatment method for this reason is relatively responsible, because it may involve the traceability of the magnetic rod coil inductor product itself. Any product quality problem means that there may be a large number of substandard products in the batch of magnetic bar coil inductors produced by the supplier.   The correct way to deal with it is to determine which aspect of the product causes the quality problem. Is it the poor quality of the enameled wire used, or the coil winding does not meet the requirements, or the problem with the core powder formula that causes abnormal heating? This requires our technical intervention and a comprehensive test and analysis of the product to find out the problem. As long as we can determine the problem, we can provide specific and effective solutions.