Design strategy for frequency conversion smart home appliance application circuit

　　There are many ways to implement frequency conversion control of frequency conversion appliances, each with its own advantages and disadvantages, but which method has lower cost, higher efficiency and better effect is the problem we are concerned about. This article introduces a sensorless vector control technology solution for frequency conversion appliances based on the IRMCF341 (＄3.8860) microcontroller from the shallow to the deep. This article briefly describes the frequency conversion technology, introduces the relevant knowledge of IRMCF341 (＄3.8860) and IPM, and then analyzes the application of IRMCF341 (＄3.8860 ) in frequency conversion appliances. Analysis and practice show that the sensorless vector control technology solution for frequency conversion appliances based on the IRMCF341 (＄3.8860) microcontroller has many advantages such as high efficiency and low cost, and will be widely used. IRMCF341 (＄3.8860)  is a version for the development stage. Its 48K program memory is RAM, which can easily load 8051 and MCE control codes from external EEPROM. For mass production, the OTP version or mask version IRMCK341 (＄7.7580) with exactly the same pins can be used . Its typical applications are as follows:

　　hardware design

　　Main control circuit

　　IPM drive circuit design

　　The IPM (Intelligent Power Module) drive circuit mainly completes the power amplification of the six-way PWM signal generated by the 341 chip, drives the internal power tube to realize the drive of the motor. Briefly describe the market background and frequency conversion technology of variable frequency home appliances. It mainly introduces the characteristics and functions of the IRMCF341 (＄3.8860) chip, the development environment and analyzes its application in variable frequency home appliances. Due to the excellent control performance and humanized development process of IRMCF341 (＄3.8860) , it is not limited to home appliances. In addition to supporting PMSM, BLDC and other DC motors, IR's newly launched code already supports ACIM AC induction asynchronous motors, which has expanded the application of IRMCF341 (＄3.8860) in variable frequency control to a greater extent. At present, some customers have successfully developed variable frequency water pumps, variable frequency treadmills, etc. using IRMCF341 (＄3.8860) .

　　Variable frequency treadmill solution: In FOC vector control mode, it provides a sufficiently large starting torque. In the case of impact load, the speed loop and current closed-loop vector control have fast response speed. At the same time, because the main circuit uses a large-capacity smoothing capacitor, the software has been specially modified for the treadmill load, which can effectively stabilize the DC bus voltage and fully meet the requirements of the treadmill load characteristics. It can achieve 5HZ at low speed and start smoothly with no jitter. The energy-saving effect of the variable frequency water pump has exceeded the level of similar foreign products after testing.
 

　　High-performance and low-cost motor control for variable frequency home appliances sensorless control applications. Generally, the most advanced vector control technology based on magnetic field positioning is adopted, and the three-phase current reconstruction of the motor can be realized by using single resistor current sampling, thereby realizing FOC current loop and speed loop dual closed-loop vector control, and the driving mode is 180-degree sine wave. Smart home appliances are now gradually entering the public life and will be one of the hot electronic design fields in the future. In view of this, the editor has specially compiled the application circuits of smart home appliances for readers' design reference.