detailed analysis of the application scope of the 35kV high-voltage switchgear
The following is a detailed analysis of the application scope of the **35kV high-voltage switchgear**, which is
classified and described in combination with the application scenarios and technical advantages:
I. Core Scenarios of the Power System
1. Substation Power Distribution
- **35kV Substation**
- **Incoming/Outgoing Circuits**: As the main equipment of the 35kV power grid, it connects the superior
110kV/220kV substation and the inferior 10kV power distribution system.
- **Main Transformer Power Distribution**: It is used for the protection and control of the 35kV main transformer
(such as with a capacity of 6.3-63MVA), realizing the hierarchical distribution of electrical energy.
- **Urban Power Grid Reconstruction**
- Replace the old 35kV outdoor switchgear and be used in indoor power distribution centers to improve
space utilization and the protection level.
2. Regional Power Distribution Hubs
- **Cable Branch Boxes/switching Stations**
- As the high-voltage side interface in the urban medium-voltage power grid, it distributes the 35kV electrical
energy to multiple 10kV switchrooms through cables.
II. Industrial and Energy Fields
1. Large Industrial Enterprises
- **High-voltage Motor Drive**
- Directly control 35kV high-voltage motors (such as mine hoists, chemical pump units, steel mill rolling mills),
with a power usually between 2-20MW.
- **Internal Power Distribution System of the Factory**
- Supply power from the 35kV main bus to the workshop transformers (such as 35/10kV, 35/0.4kV), supporting
multi-load branch circuits.
2. New Energy Projects
- **Photovoltaic/Wind Power Step-up Stations**
- **Collection of Collector Lines**: Summarize the electrical energy of multiple 10kV/35kV photovoltaic arrays
or wind turbines through the 35kV switchgear, and connect it to the main transformer to step up the voltage to
above 110kV for grid connection.
- **Typical Configuration**: Each main transformer is equipped with 4-8 35kV switchgear panels (incoming lines,
outgoing lines, PT, metering, etc.).
- **Energy Storage Systems**
- Connect the 35kV energy storage converter (PCS) to achieve grid peak regulation, new energy consumption,
and support rapid charge and discharge protection.
3. Data Centers and Infrastructure
- **Dual Power Supply Switching**
- As the switching switch between the utility power (35kV) and the backup power supply (such as a diesel generator),
it ensures the uninterrupted power supply of IT equipment.
- **Rail Transit**
- It is used in the 35kV traction power supply system of subways and light rails to control the rectifier unit to
supply power to the catenary.
III. Special Environments and Customized Scenarios
1. High-altitude and Polluted Areas
- **High Altitude (≤4000m)**
- Customize the enhanced insulation switchgear (increase the air gap and use special insulators for high altitudes).
- **Coastal/Chemical Industrial Parks**
- Select anti-fouling flashover insulation materials (such as silicone rubber bushings) and moisture-proof designs
to withstand the corrosion of salt spray and dust.
2. Temporary Power Supply and Modular Projects
- **Prefabricated Substations**
- Box-type substations integrated with 35kV switchgear are used in scenarios such as construction sites and
temporary power stations for rapid deployment.
| IV. Application Differences with Other Voltage Levels | |||
| Scenarios | 35kV Switchgear | 10kV Switchgear | 110kV and Above |
| Transmission Capacity | 5-50MW (Economic transmission distance of 5-15km)5-50MW | <5MW (Short-distance power distribution) | >50MW (Long-distance and large-capacity power transmission) |
| Motor Drive | Directly drive high-voltage motors above 2MW | Drive low-voltage motors below 1MW | No direct application |
| New Energy Collection | The mainstream voltage of photovoltaic/wind power collector lines | Small photovoltaic projects | Main grid step-up |
| Economy | The highest cost-performance ratio in medium-voltage power transmission | The lowest cost in terminal | Require GIS equipment, and the cost increases significantly |
Conclusion
The 35kV high-voltage switchgear is suitable for the core scenarios of **medium-capacity and medium-distance
power transmission**, and it has the advantages of both voltage level and economy. It is a key device for industrial
enterprises, new energy projects, and urban power grids. When selecting the equipment, it is necessary to combine
the specific load characteristics, environmental conditions, and power grid planning to ensure the coordinated
matching with the upstream and downstream equipment.
