IGBT Rectifier application features
1, reduce the porosity, nucleation formation rate is greater than the growth rate, to promote the nucleation.
2, to improve the binding force, so that passivation film breakdown, is conducive to the matrix and the strong combination between the coating.
3, to improve the ability to cover and dispersion capacity, high cathode negative potential in the ordinary plating of the passive parts can also be deposited to slow down the form of complex parts of the prominent parts of the excessive consumption of ions due to the accumulation of "charred" Deposition of defects, for obtaining a given characteristic coating (such as color, no porosity, etc.) can reduce the thickness of the original 1/3 to 1/2, saving raw materials.
4, to reduce the coating of internal stress, improve lattice defects, impurities, holes, tumor, etc., easy to get crack-free coating to reduce the additives.
5, is conducive to obtain a stable composition of the alloy coating.
6, to improve the dissolution of the anode, without the anode activator.
7, to improve the mechanical properties of the coating, such as increasing the density to reduce the surface resistance and body resistance, improve toughness, wear resistance, corrosion resistance and can control the hardness of the coating.
The traditional electroplating suppresses the generation of side effects, improves the current distribution, regulates the liquid mass transfer process and controls the crystallization orientation. The research on the complexing agent and additives has become the main direction of the electroplating process. Nano-switching power supply to solve the traditional IGBT Rectifier defects.
In the waveform diagram of the rectifier circuit of the controllable IGBT Rectifier, it is found that the time of the first trigger pulse is the same in every half cycle of the thyristor to withstand the forward voltage, that is, the control angle α and the conduction angle θ are equal , Single-junction transistor relaxation oscillator how to accurately match with the AC power to achieve effective control?
In order to achieve the IGBT Rectifier rectifier circuit output voltage "controllable", the thyristor must be allowed to bear the forward voltage every half cycle, the trigger circuit to send the first trigger the same time, this mutual work, known as The trigger pulse is synchronized with the power supply.
How can we achieve synchronization? We look at the regulator circuit diagram (above). Note that the power of the single-junction transistor relaxation oscillator is taken from the full-wave pulse DC voltage output from the bridge rectifier circuit. When the thyristor is not turned on, the capacitor C of the relaxation oscillator is charged by the power supply. When the LED rises to the peak voltage UP according to the exponential law, the single junction transistor VT turns on. During VS conduction, the AC voltage and current , At the same time, the voltage drop across the VS is small, forcing the relaxation oscillator to stop working.