3500-32 能耗小的并联泵组合理运行搭配及调速方式

First, the control theory of rational operation collocation and speed regulation mode of parallel pump group with low energy consumption

Control principle

In the pump station system process parameters (flow, pressure), set parameters (pump, motor, speed regulating device) are determined, using the small square theory to find out the function relationship between H-0, using the parallel pump group characteristic curve fitting method, automatically find a set of low energy operation collocation and speed regulating mode. That is to optimize the pump combination scheme (the pump group with reasonable operation conditions runs stably within the high efficiency range). Of course, the optimized pump combination program is not necessarily the realization of each pump before the worry, here refers to the body effect after the optimization of the pump combination in a home station, you can image that the entire pump station has been optimized after each pump combination program as a “water record” we call the pump combination program “virtual pump”, and this “virtual pump under a certain pressure and flow, The characteristic equation and characteristic curve of “virtual pump” are calculated by the theory of small square method, and the range of “virtual pump” rich efficiency is found out. When the operating point of the “virtual pump” is not running in the high efficiency zone, the control system can automatically adjust the operating condition point of the branch frequency pump by setting parameters according to the phase theorem of the pump speed regulation and the principle of equal efficiency, so that the operating point of the dynamic operation of the “virtual pump” is in the high efficiency zone, and the energy consumption per unit flow is small

2. Technical design and implementation

1, pumping station process and control process

1.1 Process flow of pumping station

Our company Dongzhuang water distribution pump station adopts direct pumping method to distribute water to a DN800 pipeline, the final distribution water flow is 2100m3/h, the outbound force is 0.39MPa. The main equipment is: 2 Japanese MISUTISHIF series inverter; 4 centrifugal water pump, each water pump is equipped with an outlet electric valve, a lifting water valve, 2 vertical submersible pumps (drainage), 2 vacuum system (pump vacuum annual water). In addition, the equipment does not have the automatic instrument competition related to the system. Starting from the goal of the peak sample of the section, the final pump group is equipped with the pump to optimize the tower configuration and adjustment scheme in Table 1

When the effective water depth of the water distribution pump is above 1.8 meters, it is self-filling: vacuum water is needed below 1.8 meters. The number of pumps on and off, according to the water level of the clear pool, service pressure and flow parameters automatically optimize the combination, and the operation of the machine pump through the PLC 10 interface in time to the force control configuration software real-time database, so that the staff on duty at any time to monitor the operation of each machine pump, drainage pump according to the water level of the sump, vacuum pump according to the vacuum water requirements to automatically determine the open and stop the pump. In the electrical circuit, the high and low music switch are manual operation, the power and instrument data are recorded and automatically transmitted, and the duty personnel can see the power consumption per unit flow of each virtual pump and other parameters from the display screen in time

1.2 Control process of the pump station The pump control in the pump station can adopt on-site manual control mode, semi-automatic control mode, automatic control mode. When the operating pump fails, the standby pump will automatically start. Set the parameters (flow and pressure) of the virtual pump, and display the theoretical H-Q characteristic curve and pipe network characteristic curve of the virtual pump