A prefabricated substation is directly connected to the high-voltage power transmission network and mainly consists of a transformer room, a high-voltage room, and a low-voltage room. Generally, electrical appliances cannot be directly connected to the substation; a distribution room is required. The distribution room is directly connected to the substation, allowing the appliances to connect and use power from there. The main purpose of the distribution room is to protect the substation; if a major problem occurs with the appliances, the distribution room will be the first to be affected. Let's discuss the differences between the two:
First, let's introduce the definitions of both:
A prefabricated substation typically consists of a high-voltage compartment, a transformer compartment, and a low-voltage compartment. It is a relatively simple power distribution device; the selection of its transformer section can generally follow standard procedures, and the capacity is generally no more than 2500 kVA.
Temporary transformer substation: A transformer substation used temporarily, such as a temporary transformer at a construction site, which will be dismantled in the future and not permanently retained for use;
The first type is mainly used in urban residential areas and streets. When there is a need to increase the voltage during peak electricity consumption periods, our transformer substations are required.
The second type is mainly used for temporary power supply, such as at construction sites where we need to modify electrical equipment in the presence of existing buildings. Transformer boxes are also frequently used in field operations, such as at construction sites, docks, airports, etc.
Function: Box-type substations are used in high-rise residential buildings, luxury villas, squares and parks, residential communities, small and medium-sized factories, mines, oil fields, and temporary construction power supply sites, for receiving and distributing electrical energy in the power distribution system.
Power distribution room:
1. Definition: A power distribution room, also called a power distribution station, is defined in national standards as a station containing only high-voltage power distribution equipment that performs the functions of switching and distributing electrical energy, without a main transformer on the busbar;
2. The voltage level of the power distribution room is below 35KV, and it is equipped with switches, transformers, capacitors, and related protection and measuring devices.
3. To put it simply: build a house, put the transformer inside, and add incoming and outgoing line cabinets, and that becomes a power distribution room;
4. Large-scale facilities, including multiple transformers, high-voltage switchgear, low-voltage switchgear, etc., forming an independent location or area within a building to transform and distribute electrical energy;
5. The difference between a distribution station and a substation is that a distribution station does not have a transformer, while a substation does have a transformer; distribution stations and substations mainly refer to the distribution rooms in residential areas or buildings.
6. The power distribution room is a critical part of the building's power supply system and is staffed by a dedicated electrician who operates it 24 hours a day. Unauthorized personnel are not permitted to enter without the permission of the management manager or department head.
7. Duty personnel must be certified and familiar with the status of power distribution equipment, operating procedures, and safety precautions;
8. The duty officer must closely monitor the readings of the voltmeter, ammeter, and power factor meter, and overloading of the air switch is strictly prohibited;
9. Regularly keep the floor of the power distribution room and the exterior of the equipment dust-free;
10. Switching operations on equipment in the power distribution room shall be performed solely by the on-duty personnel; other personnel present shall only supervise and shall not interfere.
11. It is strictly forbidden for two people to operate the switching circuit simultaneously to avoid errors.
As can be seen from the above, the main differences between a prefabricated substation and a power distribution room are as follows:
1. Construction:
The prefabricated substation is relatively simple to construct. It involves building a foundation and cable trench, placing the substation on the foundation, connecting the high and low voltage incoming and outgoing lines, debugging, and it's complete.
The underground power distribution room is relatively complex, but it's simpler because of the underground parking garage. Equipment installation and fire prevention and other safety measures are more complex and potentially more expensive.
2. Operation and Maintenance:
The operating environment of prefabricated substations is relatively harsh, exposed to outdoor wind and sun, and their sealed design makes inspection difficult. Their high integration also hinders maintenance.
The power distribution room does not have the above-mentioned problems. Multiple operating modes can be designed according to requirements;
3. Reliability:
The power distribution room is likely to be higher up. This is because the prefabricated substations are highly integrated, leading to greater mutual interference between the various devices.
4. Environmental impact:
The transformer substation is located on the ground, taking up space and affecting the layout of ground facilities and the community's landscape. It also has some impact on safety and residents' activities.
The power distribution room is not affected in this way.
5. Cost:
The price of the transformer substation equipment itself is not low, and the operating and maintenance costs are even higher.
The overall cost of the power distribution room equipment is estimated to be not much higher than that of the transformer substation. Due to the underground parking garage, the civil engineering costs will not increase significantly. The only impact is that it occupies the area of the underground garage, which may reduce the number of parking spaces and affect revenue from this area.
6. The use of substations is more mature than that of prefabricated substations:
Overall, it's better to build an underground power distribution room.
Transformer box-type substations are generally used only as a last resort;
Substations are the most mature method in power supply systems. However, for power supply facilities in residential communities, safety and reliability should be the top priorities.
