What is a high-frequency switching power supply?
Electroplating is the process of converting electrical energy into chemical energy. In this process, metal ions acquire electrons and are reduced to metal atoms, which are arranged in a certain pattern to form crystals and become coatings. The DC electroplating power supply is the source of electrons and the driving force for the crystallization of metal atoms. Therefore, the role of power supply in the electroplating process is very important.
High frequency switching power supply
Before the mid-1960s, people used AC-DC generator sets to provide direct current for electroplating. When adjusting the output of a DC generator, it is necessary to use the output of the DC generator as a sampling signal and adjust the speed of the AC motor to change the DC output, known as the "AC-DC-AC group". This system, due to its high reliability, once dominated the field of electroplating (along with arc rectifiers, which were phased out earlier). To this day, their presence can still be seen in some large domestic factories. However, this system had extremely low efficiency and therefore withdrew from the historical stage shortly after the birth of power electronics technology. We refer to the DC power supply system represented by AC and DC generator sets as the first generation DC electroplating power supply.
Before power electronics differentiated from electrical technology, high-power silicon rectifiers were widely used in industrialization. Therefore, in the field of electroplating, the so-called "autotransformer+silicon rectifier" DC electroplating power supply emerged, which uses autotransformers to regulate AC voltage and then rectifies it with high-power silicon tubes (stacks). Although this system has made some progress in technology compared to "AC-DC generator sets", it is very inconvenient due to the need to use motors or manpower to drive the voltage regulating end of the autotransformer in control. At the same time, its efficiency has not improved at all, and its precision and ripple are also poor. This is the so-called second-generation DC electroplating power supply.
In the mid to late 1950s, thyristors were born at Bell Laboratories in the United States. This will bring revolutionary benefits to the power electronics industry, including electroplating power supplies. The DC electroplating power supply with thyristor as the core was developed in this context.
There are two main forms of controllable silicon electroplating power supply in terms of circuit structure: one is to use controllable silicon to regulate the voltage on the primary side of the power frequency transformer, and then use silicon tube multiphase rectification on the secondary side; The second is to directly use thyristors for voltage regulation and rectification on the secondary side of the power frequency transformer. Regardless of the form, mature regulation and control principles are applied through electronic circuits to control the conduction angle of thyristors, greatly improving the output characteristics of thyristor electroplating power supplies compared to previous products. Under rated load conditions, satisfactory accuracy, ripple, and efficiency can often be achieved, especially in terms of efficiency, which has significantly improved compared to previous products and has a wide power range. These excellent characteristics made it the mainstream of DC electroplating power supply as soon as it appeared. Until now, this type of power supply is still widely used in China, and industrialized countries abroad are also using this type of power supply in the field of high-power power supply. We call it the third generation DC electroplating power supply.
