HP Heat Sink for Mining Explosion-proof Inverter
Explosion-proof squirrel-cage motors are widely used in the electric controlling system of belt conveyor, scraper conveyor, fan, water pump and winch for coal mine wells. The controlling method of these motors is simply direct controlling, so it does a great damage to the motor and the mechanical transmission. In recent years, the SCR AC depressing voltage speed regulation technology has received some usage. However, the starting characteristic of AC depressing voltage soft starter is not good enough, so there's a large damage to power grid done by the SCR AC depressing voltage speed regulation technology. Furthermore, it also requests large capacity of the mobile substation and then its application is somewhat limited. With the significant technology changes of the electric drive field, the AC speed regulation technology is greatly improved. Variable frequency controlling method overcomes the above problems, and receives excellent speed regulation characteristics and energy-saving effect.
Currently, the 660V and 1140V voltage are the most widely used voltage level in China's coal mines. The stand-alone power of production equipment grows with the increasing in its production capacity. However, the power dissipation of inverter is considerable to amount for 4%~5% of its general capacity. Evidently, the larger the explosion-proof inverter power is, the harsher the heat dissipation problem is. If not properly solved, the problem must be adverse to the performance stability and shorten the service life of the inverter. Common inverters often dissipate the heat using air cooling or water cooling. All the electric components of explosion-proof inverter are sealed in its shell, so it's difficult to cool it by air cooling. On the other hand, water cooling needs water circulation system and heat sink, which are large volume and inconvenient to install and maintain. So neither air cooling nor water cooling is a good solution to the complicate conditions of coal mine wells. Under this circumstance, HP heat sink is the reasonable technology to solve this problem and keep the inverter and rectifier circuit working within the normal temperature range. HP heat sink works with natural cooling, which doesn't need fan and is free of noise and maintenance, so it's safe and stable. Under the circumstance of natural convection cooling, the performance of HP heat sink is ten times better than that of pure aluminium heat sink.
According to the requests of our customers, WTL has been designing and manufacturing several sets of explosion-proof HP heat sinks, which are widely used in the fields of coal mining, oil and chemical industry. Especially, WTL provides excellent solution to the coal-oriented explosion-proof and self-safe inverter with the power of 90~450 kW (660V voltage level) and 185~560 kW (1140V voltage level). Among these HP heat sinks we have produced, the heat dissipating power ranges from several kW to more than 10,000 kW at the requests of our customers. For example, the heat sinks for 250 kW-1140v/660v coal-oriented explosion-proof and self-safe and 2000 kW-10000v/6000v high voltage inverter, which have been successfully put into operation, is proved to be effective, stable and reliable.
The characteristics of coal-oriented explosion-proof HP heat sink produced by WTL are listed as follows:
1) Using HP as heat transferring components, it's quick to response, efficient of heat transferring and prominent of heat dissipating.
2) Using aluminium fins, it's light and small.
3) Segregating the heat source and the cold source, it's of ideal isotherm, able to transfer much heat with small temperature difference.
4) High performance of explosion-proof, simple structure, easy to install and maintain.