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How are the differences and similarities between current transformers and voltage transformers?

            How are the differences and similarities between current transformers and voltage transformers?

   Current transformers (CT) and voltage transformers (PT/VT) are two crucial and important measurement and protection devices in the power system. Here are their similarities and differences:

   Similarities:

  1. Working principle:

   Are based on the principle of electromagnetic induction (mutual inductor), through the primary and secondary side of the windings to achieve the transformation of the signal.

  2. Error requirements:

  Have accuracy levels (such as 0.2, 0.5, etc.), to meet the needs of measurement or protection.

 Differentia

 
 
Differentia  of current transformer and voltage transformer 

Comparative item

Current  transformer

Voltage transformer

Connection method

Connected in series in the primary circuit.

Parallel connection in the primary circuit

Secondary side status

The secondary side must never be open-circuited during operation (otherwise, it generates dangerously high voltage).

Short-circuiting on the secondary side is strictly prohibited (otherwise the equipment will be burned)

Load characteristics

The secondary load impedance must be very low (near short-circuit conditions).

Load impedance on the secondary side needs to be large (close to an open circuit)

Typical application

Used for current measurement and overcurrent protection.

Voltage measurements, over-voltage/under-voltage protection

 Key considerations

CT: Secondary open circuit will lead to high voltage danger, need to be operated after reliable short circuit.

PT: secondary short circuit will lead to high current, need to add fuse protectio

The two complement each other in the power system, and work together to ensure high-precision measurement and safe system operation.

 

10kV Potential Transformer (PT or VT) is produced by Shaanxi West Power Tongzhong Electrical Co., Ltd. is a key device used for voltage measurement, energy metering, relay protection and system monitoring in power systems. Its function is to convert the voltage on the high voltage side (10kV) into a safe voltage on the low voltage side (standard value such as 100V or 100/V) for use by instruments, protection devices and control systems.

 

10kV Potential transformer offers numerous advantages:

1.Good insulation performance

The epoxy resin fully enclosed epoxy casting structure is adopted. This structure makes the transformer have high insulation strength, which can effectively prevent the internal circuit from contacting the external environment, and avoid the normal operation and measurement accuracy of the equipment affected by leakage, discharge and other problems. In addition, the insulation structure has good moisture and anti-fouling capabilities, can adapt to a variety of complex operating environments, and can still maintain stable performance in harsh climatic conditions and polluted environments.

2.High precision

For functions such as energy metering, voltage monitoring and relay protection, the accuracy of measurement is crucial. During the design and manufacturing process of JDZX9-35 voltage transformer, the material selection and processing technology of key components such as core and winding are strictly controlled, which can accurately convert high voltage into low voltage and provide reliable data support for the metering, monitoring and protection of power system.

3.Compact structure

small size and light weight: The overall structure is compact and has a mounting plate at the bottom, which is easy to install and fix. It can also be easily arranged in places with limited space such as substations and distribution rooms. Its light weight also facilitates operation during transportation and installation, reducing construction difficulty and labor costs.

4.Safe and reliable operation

When excited at rated voltage, this type of transformer can withstand an external short circuit of one second without damage. It has high short-circuit tolerance and can maintain stable performance when a power system failure occurs, avoiding more serious power accidents caused by transformer failure and ensuring the safe operation of the power system.

5.Easy to maintain:

The transformer does not require special maintenance, only regular cleaning of surface dirt is required, which reduces maintenance costs and workload.

Fully insulated structure has strong applicability

The fully insulated structure makes the transformer not only suitable for general power systems, but also can be used normally in some special occasions with high insulation requirements, such as high altitude areas and humid environments, thus expanding its application range.

6.Good electromagnetic compatibility

It can work stably in complex electromagnetic environments, is not affected by external electromagnetic interference, ensures the accuracy and reliability of the measurement results, and will not cause electromagnetic interference to other power equipment.

10kv-potential-transformer

                              

 Should you have any requirements in these fields, please feel free to contact us as per following information:

 Email: xdtz04@westpowerelectric.com

 Website: https://www.xdtzelectrical.com/

 Tel:+86 917 3661109

Mobilephone(whatsapp ): +86 18091765882