More and more domestic switchgear manufacturers are going global, producing switchgear products for overseas customers. Although the requirements for medium-voltage air-insulated switchgear are similar in China and abroad, there are some differences. Using switchgear that meets domestic standards for overseas projects may lead to problems such as unmet special needs, unreasonable structural design, and large quantities of switchgear, which may affect continuous supply. Therefore, it is necessary to customize switchgear according to the requirements of overseas customers in order to continuously and stably sell products all over the world.
Due to differences in specific applications and usage habits, domestically produced switchgear often encounters the following problems when used in overseas projects:
1. The cabinet layout is not compact enough, making it impossible to design according to the customer's initial plan requirements. Many components cannot be installed in a single switchgear, necessitating an increase in the number of switchgear cabinets.
2. The cabinet is too large. Customers often require smaller products; for example, a 17.5kV switchgear overseas may need to be supplied domestically as a 24kV switchgear.
3. Internal arc discharge mechanisms are inadequate. Depending on the site installation location, overseas customers often require the use of pressure relief baffles, pressure relief channels, and other structures to prevent internal arc discharge. 4. Pressure relief from faults;
5. High safety requirements: Many customers require additional mechanical interlocks, such as mechanical key locks, to meet system application safety requirements. Key locks need to be configured according to the system diagram requirements;
6. High-voltage compartments such as cable rooms generally do not use lighting and typically require infrared observation windows for cable head temperature measurement;
7. Complex secondary requirements: Different applications have different requirements for the current transformer secondary winding ratio and accuracy. Some require multiple windings, and control voltages vary;
8. Special color requirements may apply to cabinets, conductors, busbars, primary simulation diagrams, and opening/closing markings. It is recommended to follow the customer's technical specifications or confirm with the customer.
Overseas projects have high requirements for product safety, product size, and compact application solutions. Reducing the number of cabinets means a smaller footprint and lower investment in the switch room. Using a busbar grounding switch for grounding during main busbar maintenance is safe, convenient, and reliable. The busbar voltage transformer is installed on the top of the cabinet, which can reduce the number of busbar equipment cabinets. The incoming line cabinet is equipped with a grounding switch and a voltage transformer. The voltage transformer is integrated into the incoming line and installed in the cable compartment. The handcart-type structure eliminates the need for a separate compartment consisting of a contact box and a valve mechanism. The single busbar is segmented, and each segment of the busbar is equipped with a busbar grounding switch and a busbar voltage transformer on the top of the cabinet. The incoming line has a grounding switch and a voltage transformer. The bus tie cabinet and some outgoing line cabinets are equipped with busbar-side current transformers. The busbar lifting cabinet is equipped with a grounding switch and a voltage transformer to realize voltage measurement and maintenance grounding of the busbar segment.
