CN217232040U - Distributed pumped storage system combined with urban water supply system - Google Patents

Abstract

The utility model discloses a distributed pumped water storage system combined with an urban water supply system. It includes a water pump unit and a generator unit arranged between a water supply plant and a sewage treatment plant with a high potential energy difference; between the water supply plant and the urban water load center, and between the urban water load center and the sewage treatment plant, there are The first water transmission pipeline, which is used for connecting the water supply plant and the urban water load center for water supply and for connecting the urban water load center and the sewage treatment plant to discharge waste water; A second water delivery pipeline is also arranged between the treatment plant and the urban water load center, and the second water delivery pipeline is used for connecting the sewage treatment plant and the waterworks for pumping water, or for connecting the sewage treatment plant and the urban water load center for water supply; The generator set is arranged on the first water delivery pipeline, and the water pump set is arranged on the second water delivery pipeline. The utility model not only has the capability of water supply, but also has the capability of storing energy and generating electricity.

Description

A Distributed Pumped Storage System Combined with Urban Water Supply System

technical field

The utility model belongs to the technical field of urban water supply systems, in particular to a distributed pumped water storage system combined with an urban water supply system.

Background technique

The urban water supply system is the most basic public utility in the city, which belongs to the category of infrastructure, and the government is the main body of supply to ensure its public welfare. The importance of the urban water supply system as a public good is also reflected in its irreplaceability, that is, whether it is a big city or a small city, water plants and sewage treatment plants can be seen.

At the same time, the need to build renewable energy power plants in cities is increasing. It can be expected that the rooftop distributed photovoltaic power station will be vigorously developed in the future, and its demand for energy storage will also be more urgent.

Utility model content

The purpose of this utility model is to solve the shortcomings of the above-mentioned background technology, and provide a distributed pumped storage system combined with the urban water supply system.

The technical scheme adopted by the utility model is: a distributed pumped water storage system combined with an urban water supply system, comprising a water pump unit and a generator unit arranged between a waterworks and a sewage treatment plant with a high potential energy difference; A first water transmission pipeline is provided between the factory and the urban water load center, and between the urban water load center and the sewage treatment plant, and the first water transmission pipeline is used for connecting the water supply plant and the urban water load center for water supply and for Connecting the urban water load center and the sewage treatment plant to discharge waste water; a second water transmission pipeline is also provided between the waterworks and the sewage treatment plant or between the sewage treatment plant and the urban water load center, and the second water transmission pipeline is used for Connecting the sewage treatment plant and the waterworks to pump water, or connecting the sewage treatment plant and the urban water load center for water supply; the generator set is arranged on the first water delivery pipeline, and the water pump set is arranged on the second water delivery pipeline.

In a further preferred structure, the two units of the water pump unit and the generator unit are both doubly-fed asynchronous motors, and the rotor terminals of the two units are connected to a group of back-to-back converters, and the converters are controlled by power semiconductor technology. , the stators of the two units share a unit transformer and are connected to the power grid.

In a further preferred structure, the urban water load center or the water pump unit is connected to the wind farm and the photovoltaic power station for power supply.

The beneficial effects of the utility model are: the utility model combines wind farms, photovoltaic power stations, distributed pumped storage systems, and urban water supply systems in or around the city, aiming at the construction of cities with energy storage needs, so that the system has both It also has the ability to store water and generate electricity. The utility model is suitable for cities and towns with energy storage needs, especially for use with wind farms and photovoltaic power stations in or around cities. It will greatly improve the power supply reliability and absorption capacity of renewable energy sources such as wind farms and photovoltaic power stations in or around the city. It has the advantages of small size, low renovation cost, and flexible energy storage response.

Description of drawings

Figure 1 is a schematic diagram of the pumping working condition of the distributed pumped storage system combined with the urban water supply system;

Figure 2 is a schematic diagram of the water supply conditions of the distributed pumped storage system combined with the urban water supply system;

Figure 3 is a schematic diagram of the power generation working condition of the distributed pumped storage system combined with the urban water supply system;

Figure 4 is the electrical connection diagram of the urban water supply system + distributed pumped storage system.

In the figure, 1-Water Works, 2-Sewage Treatment Plant, 3-Water Pump Unit (301-First Turbine), 4-Generator Unit (401-Second Turbine), 5-Urban Electricity Load Center, 6-First Water pipeline, 7-second water pipeline, 8-wind farm, 9-photovoltaic power station, A-transformer, B-converter.

Detailed ways

The present utility model will be further described in detail below in conjunction with the accompanying drawings and specific embodiments, so as to facilitate a clear understanding of the present utility model, but they do not constitute a limitation on the present utility model.

As shown in Figures 1-4, the utility model includes a water pump unit 3 and a generator unit 4 arranged between a water supply plant 1 and a sewage treatment plant 2 with a high potential energy difference; the water supply plant 1 and the urban water load center 5 There is a first water pipeline 6 between the urban water load center 5 and the sewage treatment plant 2, and the first water pipeline 6 is used for connecting the water plant 1 and the urban water load center 5 for water supply and for communicating with each other. The urban water load center 5 and the sewage treatment plant 2 discharge waste water; there is also a second water transmission pipeline 7 between the water works 1 and the sewage treatment plant 2 or between the sewage treatment plant 2 and the urban water load center 5. The second water transmission pipeline 7 is used to connect the sewage treatment plant 2 and the water supply plant 1 for pumping water, or to connect the sewage treatment plant 2 and the urban water load center 5 for water supply; the generator set 4 is arranged on the first water transmission pipeline 6, so The water pump unit 3 is arranged on the second water pipeline 7 .

The two units of the water pump unit 3 and the generator unit 4 are doubly-fed asynchronous motors. The rotor terminals of the two units are connected to a set of back-to-back converters B. The converters are controlled by power semiconductor technology. The stators of each unit share a unit transformer A and are connected to the power grid.

The urban water load center 5 or the water pump unit 3 is connected to the wind farm 8 and the photovoltaic power station 9 for power supply.

As shown in Figures 1 and 2, the distributed pumped storage system combined with the urban water supply system can be used with wind farms 8 and photovoltaic power stations 9 in or around the city. When the output of wind power and photovoltaics is excessive, in addition to providing urban electricity load, they can also use the remaining output to drive the water pump unit 3, and upgrade the clean water processed by the sewage treatment plant 2 to the water supply plant 1; When the demand for urban water surges , when the water supply of the upstream waterworks 1 is insufficient, it can also be temporarily changed to supply the clean water processed by the sewage treatment plant 2 to the urban water load center 5 . As shown in FIG. 3 , when the wind power and photovoltaic output are insufficient, the upstream waterworks 1 can increase the water discharge to drive the generator set 4 to generate electricity to compensate the urban water load center 5 for domestic power supply.

The available potential water energy E (unit: Joule) of the distributed pumped storage system combined with the urban water supply system is estimated as follows:

E=ρghVη

In the formula, ρ is the density of water (the density of water is 1000kg/m ³ ), g is the acceleration of gravity (the value is 9.8m ² /s), h is the water head height (unit: m), and V is the upper reservoir The storage capacity (unit: m ³ ), η is the power generation efficiency of the system (unit: %).

The distributed pumped storage system combined with the urban water supply system usually has multiple waterworks as the upper reservoir, and its storage capacity is calculated as:

V=∑A _i d _i

In the formula, A is the reservoir area of each waterworks (unit: m ² ), and d is the available depth of each waterworks reservoir (unit: m).

In terms of unit selection, a "two-pipe, two-machine" unit is selected, and a generator and a motor are arranged on the two water pipes respectively. That is to say, on the above two water pipelines, the unit workshops are respectively set. A variable-speed generator set 4 is installed in the existing first water transmission pipeline 6 from the waterworks 1 to the urban water load center 5 and then to the sewage treatment plant 2 . A variable speed water pump unit 3 is installed in the second water transmission pipeline 7 between the newly built waterworks 1 and the sewage treatment plant 2 .

The micro-pumping storage system combined with the urban water supply system chooses the "two-pipe, two-machine" arrangement, which is not only the actual need of the engineering design, saves the cost, but also improves the dynamic response of the energy storage system. This solution does not require separate design and purchase of reversible pumped storage units, which saves construction costs; at the same time, the two-unit solution can improve the dynamic response capability of pumped storage power stations when used in conjunction with new energy power stations.

The combination of distributed pumped storage system and photovoltaic power station aims to make the overall output of the power generation system not affected by environmental and climatic factors. For the unit selection of the distributed pumped storage system, in order to improve the dynamic response of the pumped storage power station when it provides auxiliary services for wind farms and photovoltaic power stations, variable speed units are used. Compared with fixed-speed units, the advantages of variable-speed units are very important for new energy power sources with unstable output.

In the power generation condition, the power decoupling control of the output of the generator set 4 is designed to realize the precise control of active power and reactive power; similarly, for the operating condition of the water pump set 3, the variable speed drive unit drive motor set is designed to adopt the direct torque control technology. , so as to directly control the mechanical torque of the motor.

Contents not described in detail in this specification belong to the prior art known to those skilled in the art.

Claims (3)

1. a distributed pumped-storage system combined with an urban water supply system, is characterized in that: comprising the water pump unit (3) and the A generator set (4); a first water transmission pipeline ( 6), the first water pipeline (6) is used for connecting the water supply plant (1) with the urban water load center (5) for water supply and for connecting the urban water load center (5) with the sewage treatment plant (2) for discharging waste water ; There is also a second water pipeline (7) between the water works (1) and the sewage treatment plant (2) or between the sewage treatment plant (2) and the urban water load center (5), and the second transmission pipeline (7) is also provided. The water pipeline (7) is used for connecting the sewage treatment plant (2) and the waterworks (1) for pumping water, or for connecting the sewage treatment plant (2) and the urban water load center (5) for water supply; the generator set (4) is provided with On the first water delivery pipeline (6), the water pump unit (3) is arranged on the second water delivery pipeline (7). 2. A kind of distributed pumped storage system combined with urban water supply system according to claim 1, is characterized in that: two unit types of described water pump unit (3) and generator unit (4) are double-fed Type asynchronous motor, the rotor terminals of the two units are connected to a set of back-to-back converters (B), the converters are controlled by power semiconductor technology, and the stators of the two units share a unit transformer (A) to connect to the grid. 3. A distributed pumped storage system combined with an urban water supply system according to claim 1, characterized in that: the urban water load center (5) or the water pump unit (3) is connected to the wind farm (8) and the The photovoltaic power station (9) supplies power.

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