Business knowledge learning (1)

1. What is the difference between power grids and distribution networks?

The main network refers to the power grid with voltage levels of 110KV and above. It is mainly used to connect high-voltage (220KV or above) power grids in the region.

A distribution network is a power grid with a voltage level of 35 kV or lower. It is used to supply power to various power stations and various power loads in the city.

2. What is the difference between a device and a secondary device?

One-time equipment refers to all equipment directly related to the high voltage side, such as transformers, isolating switches, circuit breakers, transformer and so on.
Secondary equipment refers to equipment related to control protection, such as electric meters, protection relays, and communication equipment.
The biggest difference between the two lies in the different voltage levels. One device is designed based on the high-voltage side, with a strong voltage. The secondary device basically carries a weak current.
Another thing to note is that one device is divided into one side and two sides, such as transformer and transformer, but it is still a single device.

A device that completes the power generation-transmission-distribution function is called a one-time device, such as a generator, circuit breaker, current and voltage transformer, transformer, and lightning arrester. It controls a single device, the protection equipment is called secondary equipment, such as relays, control switches, indicator lights, and measuring instruments.

3. Public and specialized users

A public transformer is a public transformer set up by the power supply department in the power supply area for the majority of users. His property is owned by the Power Supply Bureau. The user powered by this transformer is a public transformer user.

Public variable users are users whose voltage levels are less than 1kV. Special variable users are users whose voltage levels are greater than or equal to 1kV.

4. Concept and correlation of metering points

The Metering point is the installation location of the metering device.

Metering points are divided into charging points and metering points for power customers.

Electricity customer billing point refers to the electric energy metering point for settlement of electricity fees between Power Grid Enterprises and power customers.

The Metering points are divided into settlement points and assessment points based on their nature. They are divided into the following categories:

1. Power Generation Access Gateway: refers to the power exchange point between power generation companies (plants and stations) and the group companies and their power supply companies.

Ii. Transnational Transmission Gateway: refers to the power exchange point between the State Grid Corporation system and power grid enterprises in other countries or regions.

3. Cross-region Transmission Gateway: refers to the power exchange points between the State Grid Corporation and the Southern Power Grid Corporation, between the State Grid Corporation and its regional Power Grid Corporation, and between the regional Power Grid Corporation of the State Grid Corporation, this includes a power metering point used to calculate the percentage of Line Loss apportioned.

Iv. Cross-province Transmission Gateway: refers to the power exchange point between the Group Corporation and other provincial power companies of China North power grid.

5. Provincial Power Supply Gateway: refers to the power exchange point between the Group Company and the municipal power supply companies and between the municipal power supply companies.

6. Municipal Power Supply Gateway: power exchange points between municipal power supply companies and directly supplied county-level power supply enterprises.

7. Electricity supply points for sale in the province: metering points for electricity consumption between the municipal Power Supply Company and the County Power Supply Company for sale in the province.

8. Internal Assessment MARK: electric measurement points used by power supply enterprises for Economic and Technical indicator analysis and assessment, this includes the energy metering points used internally by Power Grid Enterprises to assess Line Loss, change loss, busbar power balance, and station area loss.

5. Area

In an electric power system, the area refers to the power supply range or area of a transformer. It is the term of electricity economic operation management.