DC engine speed governor is the equipment to regulate the speed of DC motor. It is one of the typical products in industrial application. Whether the internal circuit layout or the copper joint collocation must be perfect. Tai Xing Terminal Co., Ltd. is a professional terminal manufacturer in China. It produces LC and LZ terminals. LS series PCB terminals are widely used in the production of DC motor speed governors. Two typical customer cases are listed below.
This DC engine speed control governor is made by Jiangxi Wan Power Generator Co., Ltd. LC and LZ series male and female PCB terminal. LC1 series products have needle spacing of 3.5, 3.81, 5.0, 5.08, 7.5, 7.62 pole 2-24 lines, can provide with screw fixed socket matching, seismic connection. The plug uses side connection technology, that is, the direction of the screw is perpendicular to the wire direction. LZ is perfectly matched with LC series.
This DC engine speed control governor is mainly used in brush motors, electromagnetic motor deceleration and other fields. The terminal selection is made by Shanghai LIAN JIE Electric Co., Ltd. LW3 series terminal. LW fence type products have simple structure, plate type pressing method, intuitive and firm; wire diameter range: 0.5m-6m. This terminal is also relatively widely used in DC engine speed control governor.
Tai Xing Terminal Co., Ltd. has always adhered to the principle of "customer first, quality first" to lay a solid foundation for product development and market expansion in the field of governors.
This paper reviews the major contributions of AC motor frequency conversion technology to energy saving, environmental protection, manufacturing (production and quality improvement), transportation traction and household appliances.
Actually, for the variable frequency speed governor, namely AC motor, especially cage asynchronous motor, has a series of advantages, such as small size, light weight, simple structure, easy maintenance, low manufacturing cost and operation cost, and can operate reliably in harsh environment. But in the past, it was difficult to realize speed regulation or some speed regulation methods were not efficient enough. Therefore, DC speed regulation still occupied the field of speed regulation for a long time. Until the early 1970s, with the rapid development of power electronics, microelectronics (integrated circuits) and microcomputer technology, the long-desired frequency converter governor realized industrial production.
1 The so-called variable frequency speed governor - it converts three-phase power (50Hz) AC power (or any power) into three-phase voltage adjustable, frequency adjustable AC power supply, and sometimes the frequency converter is called VVVF. It is mainly used for the adjustment of the speed of the AC motor (asynchronous machine or synchronous machine).
2 An AC motor variable frequency speed control system consists of three parts: frequency converter drive AC motor and controller. The key equipment is frequency converter, which can realize the smooth change of motor voltage and frequency.
3 Variable frequency speed governor is incomparable in the range of frequency modulation, static precision, dynamic quality, system efficiency, perfect protection function, easy to realize automatic control and process control, etc. It is recognized that AC motor is the most ideal and promising speed control scheme, representing the future direction of electrical drive development.
4 Variable frequency gps speed limiter has been widely used in steel, metallurgy, petroleum, chemical industry, textile, chemical fiber, light industry, papermaking, rubber, plastics, electricity, water and other industries in the past 30 years. The application of VVVF for low voltage motor is very popular and mature. The variable frequency speed governor of high voltage motor is also being paid attention and gradually applied. In addition to excellent speed regulation performance, AC motor frequency conversion speed regulation also has significant energy saving and environmental protection and other important role, is an ideal speed control device for enterprise technical transformation and product renewal.
The contradiction between power supply and demand (supply exceeds demand) has a big power gap, which needs to save electricity.
According to the statistics of relevant departments, the installed capacity of China's power generation in 2002 was 31.9 billion kW, and the annual power generation capacity was 1346.6 billion KWH. Although the size of the electricity is the second largest in the world, the per capita electricity consumption is the world's reciprocal position. Moreover, the rapid development of China's economy needs more electricity. According to the demand of 8% national economic growth for 11% electricity growth, China's power generation capacity should be 570-6000 million kW by 2010, and the annual power generation capacity should reach 28000-290 billion KWH. The continuous high temperature in summer of 2003 caused the shortage of power supply in some provinces and municipalities, and forced to take measures to limit the power supply by pulling the switch. Due to the heavy burden of power network, the local power system is unstable. The above indicates that the supply and demand of our country is unbalanced and supply is less than the demand. Therefore, electricity needs to be saved.
Electricity saving benefit of variable frequency speed governor:
1 The total installed capacity of the motor in our country reaches 450 million kW, which consumes about 65% of the country's power generation. So how to save electricity is very important. Generally speaking, there are two ways to save energy: one is to improve the efficiency of the motor itself to achieve long-term and efficient operation, mainly for constant speed machinery; the other is to improve the control accuracy of motor speed, so that the motor can run at the most energy-saving speed.
2 Fan-water pump and compressor are large-scale and wide-ranging motor-driven equipment in the national economic production. The total motor capacity reaches 150 million, and the electricity consumption accounts for about 35% of the national power generation, of which about 20% ~ 30% fan-water pump needs speed regulation.
3 Variable frequency speed governor is the best scheme for the energy saving. According to the fluid theory, the shaft power of centrifugal fan pump is the three power function of rotational speed. When the rotational speed is reduced, the power consumption will be greatly reduced. For example, when the rotational speed is 50%, the mechanical power of the shaft is only 12.5%. Of course, the efficiency of the speed control scheme varies greatly. After slip, the efficiency of the hydraulic speed control device is not high, (1-S), at 50% speed, vs_50%, while the efficiency of the frequency converter governor, efficiency factor is high, vvvvF_95%~98%, and almost unchanged. Therefore, in many speed regulation schemes, variable frequency speed governor has the best energy saving effect, so it should be the first choice.