1. Explosion-proof

Because the environment used by the frequency converter is explosive gas or dust, which requires the frequency converter sealed explosion-proof, so its shell can not use ordinary shell, it is necessary to use standard explosion-proof chamber, all components of the frequency converter are installed in the explosion-proof chamber. The explosion-proof heat pipe radiator opens an observation window on the explosion-proof chamber door, installs the display part on it, and installs the start, stop and speed control on the explosion-proof chamber door.

2. Heat Dissipation

Because all the components of the frequency converter are installed in the explosion-proof chamber, the air can not flow, the heat pipe radiator heat dissipation problem becomes the key problem to be solved by the frequency converter. Here we adopt a new heat dissipation technology - heat pipe radiator technology.

(1)

Heat pipe radiator

Technical principle

Heat pipe is a heat transfer element with very high thermal conductivity. It transfers heat through evaporation and condensation of working substance in a fully enclosed vacuum tube. It has a series of advantages, such as high thermal conductivity, good isotherm, arbitrary change of heat transfer area on both sides of cold and heat, long-distance heat transfer and temperature control. The heat exchanger composed of heat pipe radiator has the advantages of high heat transfer efficiency, compact structure and low fluid resistance.

(2) Frequency Converter Structure Arrangement

The main circuit is designed as a large unit, which is installed in the back wall of the rectangular explosion-proof chamber. The back wall is connected with IGBT module, rectifier module and other heating elements through an excessive radiator. The outer wall of the explosion-proof shell is joined with a welded groove radiator, and the excessive radiator is connected with the groove radiator through a heat pipe. The heat generated inside the frequency converter is emitted through the groove radiator of the heat pipe of the excessive radiator on the back wall of the explosion-proof chamber.

3. The Difference of Main Loop Structure and Universal Inverter

(1) There is no circuit to avoid the unsafe factors caused by sparks when the relay operates, which increases the safety and reliability of the frequency converter.

(2) The capacity selection of the rectifier is twice as large as that of the general frequency converter in order to withstand the impact of capacitive charging current when the converter starts.

(3) The filter capacitors are selected as parallel electrolytic capacitors without inductance, which are large in volume, explosive and unsafe in high temperature environment, and small in volume, high temperature and high voltage resistance.