The difference between rectifier transformer and power transformer

2019-06-18 14:20:00 JuKe Technology (DongGuan) Co., Ltd. Read

The difference between rectifier transformer and power transformer

  The transformers that we generally use are generally divided into rectifier transformers and Power Transformers. When used, they will be used according to different conditions of use and specifications. The following is the similarities and differences between rectifier transformers and power transformers.
Power transformers are mainly used in power systems and daily lighting and factory power. The main purpose of the rectifier transformer: 1. Electrochemical industry; 2. DC power supply for traction; 3. DC power supply for transmission; 4. DC power supply for DC transmission; 5. DC power supply for electroplating or electric processing; DC power supply; 7. DC power supply for charging; 8. DC power supply for electrostatic precipitator;
Compared with power transformers, rectifier transformers have similarities in principle, appearance and structure, but due to their diversity, they are characterized by design, manufacture and testing:
1. Requirements for equivalent phase number:
In order to improve the power quality, the output voltage waveform of the rectifier transformer is different from the power transformer. There are only three sinusoidal pulse waves in one cycle, but the pulse wave number of each transformer in one cycle is determined according to the grid side voltage and installed capacity. Large rectifier transformer The number of pulse waves is at least 6, and more than 12, to meet the requirements of the Interim Provisions on Harmonic Management of Power Systems issued by the Ministry of Water and Electricity in 1984. The equivalent phase number is the number of pulse waves P in a week. P=6, that is, the equivalent phase number is 6.
2. Differences in output voltage:
1) Difference in salutation: Due to the close combination with the rectifier, the output voltage of the rectifier transformer is called the valve side voltage. Its name is due to the unidirectional conductivity of the diode.

2) Differences in calculation methods: Since the waveforms of the load current of the rectifier device are different, the calculation method of the output current is not only different from that of the power transformer, but also the calculation method of different rectifier circuits is different.

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Power transformer.jpg

    3. There are differences in design and manufacturing:
Due to the difference in the application between the rectifier transformer and the power transformer, it is also very different in design and manufacture from the power transformer: considering the working conditions of the rectifier transformer, the rectifier transformer is better in selecting the current density and the magnetic flux density. Low; the impedance is also slightly larger. In terms of the structure of the winding, the valve side sometimes requires two windings to supply positive and negative transmission or forward drive and reverse braking. When braking, the converter device is in the inverter working state; if the transformer has harmonic requirements, a shielding layer with a grounding terminal should be placed between the windings; the reinforcing plate and the struts are used, and the oil passage is enlarged. Measures to improve the ability of the winding to withstand short circuits; in addition, it is generally more marginal in terms of heat dissipation than is considered in the design and manufacture of power transformers.
4. Standards and experimental methods are different:
In addition to the standard of power transformers (such as GB1094-1996, GB1094.3-2003, GB1094.5-2003 "Power Transformer" GB/T6451), the rectifier transformer must also be in accordance with JB/T8636-1997 "Power Converter Transformer" carried out.
The experimental methods, experimental requirements and technical parameters allow deviations are not the same as the power transformer standards. See JB/T8636-1997 "Power Converter Transformer" for details.
Different rectifier transformers and power transformers are used differently, and each has its own advantages. Later, we should also use it according to the conditions, handle it properly, and install it safely.