The municipal rainwater drainage system is an important part of urban infrastructure. Its main function is to collect, transport and discharge rainwater to avoid urban waterlogging and protect urban facilities and residents' lives. With the acceleration of urbanization, the municipal drainage system is moving towards To develop in a more intelligent direction, these intelligent means can help improve the operating efficiency of the drainage system. However, traditional drainage systems often have problems such as high energy consumption, poor operational stability, and high maintenance costs during operation, and need to be upgraded and Retrofit to improve efficiency and reliability.
A.System Devices
Three VB-4T185 VFDs, three 160KW sewage pumps, one touch screen, one PLC, three floats for upper water level, middle water level, and lower water level, and several air switches and other components are used on site.
B.Process Flow
This system is a municipal rainwater drainage system. The system can be divided into manual control and automatic control. The manual control can open the water pump and adjust the water pump speed as needed. The automatic control system will automatically increase or decrease the number of water pumps opened according to the float signal, and automatically adjust the running frequency of the water pumps.
| Parameter | Description | Set Value | Remarks |
| F0.01 | Start/Stop Order Source | 1 | DI Terminal |
| F0.03 | Frequency Source | 2 | AI1（0-10V） |
| F0.18 | Acceleration Time | 60 | 60s |
| F0.19 | Deceleration Time | 60 | 60s |
| F6.02 | Relay1 Option | 2 | Output when alarming |
| F6.03 | Relay2 Option | 1 | Output when running |
Control the running of water pumps
Adjusting the speed: In the municipal rainwater drainage system, the water pumps are part of the core equipment. The VFD controls the flow and lift of the water pump by adjusting the speed of the water pump motor, thereby achieving precise control of the displacement. When the rainwater flow is small, the VFD can reduce the water pump speed and reduce energy consumption; when the rainwater flow increases, the VFD converter can increase the water pump speed and increase the drainage volume.
Energy saving and consumption reduction: Through speed regulation, the water pumps can always be maintained in a high-efficiency operating range, avoiding the energy waste when traditional fixed-speed water pumps operate under partial load, thus achieving energy saving and consumption reduction.
Improve system stability:
Dynamic response: The VFD has fast response capability and can quickly adapt to changes in rainwater flow, adjust the operating status of the water pump, and ensure that the drainage system always remains in a stable operating state.
Overload protection: When an abnormal situation occurs in the system (such as water pump overload), the VFD can automatically perform protective actions to avoid equipment damage and improve the safety and reliability of the system.
Intelligent control:
Remote monitoring: Modern VFDs usually have remote monitoring functions, which can realize remote monitoring and management of the drainage system through integration with the monitoring system. This helps to detect and handle system faults in time and improve operational efficiency.
Data analysis: The VFD can also collect and transmit equipment operation data to provide data support for the optimized operation of the system. Through the analysis of data, the energy-saving potential of the system can be further explored and operating efficiency improved.