【Huate Magnetic Separation Encyclopedia】Application of Electromagnetic Stirrer in Casting Industry

【Huate Magnetic Separation Encyclopedia】Application of Electromagnetic Stirrer in Casting Industry

Electromagnetic stirring can effectively stir the aluminum melt without contact, homogenize the chemical composition and temperature of the melt, reduce the formation of oxide slag, shorten the smelting time, improve productivity, and greatly reduce the labor intensity of workers. Due to the many advantages of electromagnetic stirring, electromagnetic stirrer has now become an essential equipment in the aluminum melting and casting industry.

Electromagnetic stirring can effectively stir the aluminum melt without contact, homogenize the chemical composition and temperature of the melt, reduce the formation of oxide slag, shorten the smelting time, improve productivity, and greatly reduce the labor intensity of workers. Due to the many advantages of electromagnetic stirring, electromagnetic stirrer has now become an essential equipment in the aluminum melting and casting industry.

The electromagnetic stirrer is mainly composed of a variable frequency power supply and an inductor. The variable frequency power supply converts the 50/60Hz power frequency alternating current into a 3-phase low-frequency power supply with a frequency of 0.5~5Hz. After the power supply is connected to the inductor coil, a traveling wave magnetic field will be generated. The traveling wave magnetic field penetrates the stainless steel plate at the bottom of the furnace and the furnace lining and acts on the molten aluminum, so that the molten aluminum moves regularly, so as to achieve the purpose of stirring. The magnitude and direction of the stirring force can be changed by changing the voltage, frequency and phase of the variable frequency power supply.

The latest AC, DC, AC variable frequency power supply with independent intellectual property rights jointly developed by Huate Company and Nankai University, Shandong University and other colleges and universities, is composed of a control cabinet and a variable frequency power supply cabinet to form an electromagnetic stirrer drive system.

The latest PWM control technology breaks the unified structure of the frequency converter in the past. According to the load characteristics of the electromagnetic stirrer, the special design of software and hardware is carried out. It can carry a large inductive load without adding impedance matching between the power supply and the load, and can operate at low frequencies. Stable work. The latest PWM variable frequency power supply is more suitable for application on electromagnetic stirrers; compared with the traditional variable frequency power supply, the latest PWM variable frequency power supply of Huate has the following characteristics:

1.Power factor: The power factor of the latest AC-DC-AC variable frequency power supply can reach more than 0.95, which fully conforms to the national regulations for three-phase power circuits (0.9-1). 0.95 or so is the best. If the power factor is too high, the voltage will be too high. Compared with the AC-AC structure power supply, the installed capacity of the device can be greatly reduced.

2.Static working loss: The rectifier side of the latest PWM AC-DC-AC variable frequency power supply does not need a complex control circuit, the equipment itself has less loss, and the conversion efficiency is higher than that of the traditional PWM circuit. When the equipment is in the standby state, the traditional variable frequency power supply needs to exchange large power with the power grid in order to maintain the stability of the DC bus voltage, while the latest PWM variable frequency power supply has almost no energy exchange with the power grid. In terms of lower than traditional power supply.

3. Operating loss: Since the agitator is an inductive load, not a motor-type load, there is no conversion process from mechanical energy to electrical energy, so there is almost no energy feedback during operation. The new PWM power supply realizes the reactive power exchange with the inductive load through the intermediate large-capacity DC capacitor, only the energy buffer is needed, and there is no power conversion, Therefore, the latest PWM power supply has lower operating losses than traditional variable frequency power supplies.

4. Electromagnetic radiation: Because PWM variable frequency power supply is composed of power electronic devices and modulated by high frequency carrier frequency, traditional variable frequency power supply consists of two parts: PWM rectifier and PWM inverter. The PWM rectifier measured by the power grid will generate a large number of high-order harmonics when it is working. Although LC filtering is used on the grid side, it still causes radiation interference to the grid and surrounding equipment; the latest PWM power supply has no high-frequency modulation on the grid side, and Using multi-stage LC filtering and transformer isolation, the test proves that the radiation interference on the grid side is very small, and it also overcomes the influence of the outside world on the electromagnetic stirring power supply.

5. Equipment stability: the latest PWM variable frequency power supply, the rectifier side adopts the uncontrolled rectification method of natural commutation, no complex control circuit is required, and the circuit is simple. In addition, due to the use of multiple protection circuits, including incoming line detection, DC capacitor braking unit , water temperature, water pressure, etc., especially the multiple protection of IGBT, makes the system work more reliable, and its advanced nature, maturity and stability are more obvious.

The electromagnetic stirrer produced by Huate has more than 200 domestic customers, and has been exported to more than ten countries and regions such as Brazil, Thailand and India, and has been widely praised by customers.

Shandong Huate Magnetoelectric Technology Co., Ltd. was founded in 1993 (stock code: 831387). The company is a national-level manufacturing individual champion, a national-level specialized, special, and new key “little giant” enterprise, a national-level innovative enterprise, and a national-level innovative enterprise. It is a key high-tech enterprise, a national intellectual property demonstration enterprise, a leading enterprise in the Linqu magnetoelectric equipment characteristic industrial base of the National Torch Program, the chairman unit of the National Magnetoelectric and Low Temperature Superconducting Application Technology Innovation Strategic Alliance, and the vice chairman unit of China Heavy Machinery Industry Association. . There are national-level post-doctoral scientific research workstations, comprehensive academician workstations, provincial key laboratories for magnetic application technology and equipment, and provincial magnetic and electrical engineering technology centers and other R&D platforms. Covering a total area of ​​270,000 square meters, it has total assets of more than 600 million yuan and more than 800 employees. It is one of the largest professional production and manufacturing bases for magnetic application equipment in China. Specializing in the production of medical superconducting magnetic resonance imagers, permanent magnets, electromagnetic and low temperature superconducting magnetic separators, iron separators, complete sets of mine equipment, magnetic stirrers, etc., the service scope covers mining, coal, electric power, metallurgy, non-ferrous metals and medical fields , sold to Australia, Germany, Brazil, India, South Africa and more than 30 countries.