Views: 0 Author: Site Editor Publish Time: 2022-09-27 Origin: Site
Permanent magnet synchronous motor AC speed regulation system, switched reluctance motor AC speed regulation system and asynchronous motor AC frequency conversion speed regulation system. The rare earth used to manufacture permanent magnet synchronous motor is relatively expensive and has no price advantage; At present, switched reluctance motor has not been productized or serialized, so it needs to be specially molded and manufactured, and the initial investment is large; However, the AC variable frequency speed regulation technology is quite mature, and with the rapid development of various switching power devices, the carrier frequency of PWM modulation can be quite high, so the system performance is high, especially the direct torque control (DTC) technology developed in the last 20 years, which does not need to convert the AC motor into an equivalent DC motor, thus eliminating many complex calculations in the vector rotation transformation; It is not necessary to imitate the control of DC motor, nor to simplify the mathematical model of AC motor to solve problems. Direct torque control (DTC) has become a hot topic of variable frequency speed regulation because of its fast torque response, high speed accuracy, novel control idea, simple control structure, and direct control means (direct torque control).
Recently, the Jining High-tech Zone General Trade Union and the Human Resources Department of Jining High-tech Zone jointly announced the 2024 'High-tech Craftsman' list. Li Zhenbo, General Manager of Information Technology at China Coal Group and General Manager of Zhongyun Group, was awarded the title of 'High-tech Craftsman' for his outstanding contributions and innovative spirit.
On September 30th, China Coal Group held a grand cultural performance to celebrate the 75th anniversary of the founding of the People's Republic of China with the theme of 'Forging Ahead to Celebrate the Birthday of the People's Republic of China' in the conference center. The chairman of China Coal Group, Mr. Qiu Qing, the general manager of China Coal Group, Mr. Han Yong, and all the members of the leadership team of China Coal Group attended the event and witnessed the grand celebration together with more than 1,000 employees on the spot. The cultural performance was conducted in the way of 'on-site + webcast', aiming to show the spirit of the cadres and workers of China Coal Group and express the love and blessing to the great motherland through colorful cultural programs.
On September 29th, in this season of autumn and fruitfulness, China Coal Group, full of joy and pride, participated in the ‘Harvest Celebration and National Day’, which was jointly organized by Jining Hi-Tech District Federation of Trade Unions and Jiezhuang Street to welcome the 75th anniversary of the founding of New China and the Farmer's Harvest Festival.
