Views: 0 Author: Site Editor Publish Time: 2022-09-27 Origin: Site
1. Compared with DC motor, AC motor has the characteristics of simple structure, small volume, light weight, strong overload capacity and high efficiency; The maintenance cost of DC motor is much higher than that of three-phase asynchronous motor due to the coil on the rotor and the easily worn commutating copper ring and carbon brush;
2. As DC speed regulation is operated with resistors, the power consumption is large. As AC variable frequency speed regulation does not use high energy consuming resistors, the power saving rate can reach 35%. If the electric locomotive is set with regenerative feed braking, the electric energy generated by the motor can be fed back to the battery when the electric locomotive decelerates or goes downhill, which can greatly save electric energy and extend the charging time.
3. The DC drive of the electric locomotive is graded. When driving at a low speed, the driver needs to constantly switch between gear 1 and gear 0 to obtain a slow speed. The AC variable frequency speed regulation is stepless and uniform. The speed and parking are completely controlled by the speed regulating handle, and the driver is allowed to suddenly accelerate to the maximum speed when starting at zero speed, because the frequency rise time of frequency conversion speed regulation can be set by the software.
4. The traction force of AC drive electric locomotive is larger than that of DC drive electric locomotive. The traction force of 7t DC drive electric locomotive is only 13.8KN, while the traction force of 7t AC drive electric locomotive can reach 20KN, which can reach or exceed the traction force of 10t DC drive electric locomotive. As the speed of variable frequency speed regulation increases slowly, the impact between gears is avoided and the service life of gears is extended; When decelerating, it is controlled by the speed regulating handle, and the brake pads do not need to hold the wheels to decelerate, thus reducing the wear of the brake pads.
The mining electric locomotive works in the harsh environment underground. The speed control system is in the state of frequent starting, braking, acceleration and deceleration. It also needs to adapt to the load going up and down the slope and bumpy road conditions. Therefore, the starting torque of the motor is required to be large and the overload capacity is strong. The AC speed regulating system with direct torque control can make the three-phase asynchronous motor reach or exceed the starting torque and traction characteristics of the DC motor, and enhance the starting capacity of the electric locomotive with load.
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.
