CN112128044A - A brushless doubly-fed generator-electric system for a distributed mountaintop pumped-storage power station - Google Patents

Abstract

The invention discloses a brushless double-fed power generation electric system of a distributed mountain top pumped storage power station, comprising a drain pipe, a water pumping pipe, an upper storage reservoir, a lower storage reservoir, a brushless double-fed power generation electric system, and the drainage pipe is arranged Between the outlet of the upper reservoir and the inlet of the lower reservoir, the outlet of the lower reservoir is connected to the inlet of the upper reservoir, and the power generation drive end of the brushless double-fed power generation electric system is connected to the outlet of the drain. In the pipe, the pumping end of the brushless double-fed power generation electric system is connected to the suction pipe, and multiple sets of brushless double-fed power generation and electric systems are arranged between the drain pipe and the suction pipe. The invention realizes variable speed constant voltage constant frequency and variable frequency speed regulation four-quadrant control operation, the control system capacity is small, the flexible control of active and reactive power is realized under the vector control strategy, the grid disturbance is small, and active and reactive power compensation can be achieved at the same time. At the same time, the motor itself has no slip rings and brushes, which not only reduces the cost of the motor, but also improves the safety and reliability of system operation and reduces maintenance costs.

Description

A brushless doubly-fed generator-electric system for a distributed mountaintop pumped-storage power station

technical field

The invention relates to the field of power generation equipment, in particular to a brushless doubly-fed power generation electric system of a distributed mountaintop pumped-storage power station.

Background technique

With the increase in the grid-connected capacity of renewable new energy generators, the problem of new energy consumption caused by the randomness of wind power and photovoltaic power generation will become more prominent. The grid-connected power generation from renewable energy sources such as wind power and photovoltaics also puts forward higher requirements for the peak regulation and frequency regulation capabilities of the power grid. Appropriate configuration of large-capacity power storage power supply is a key technical measure to improve the power grid regulation capability after the introduction of renewable clean energy into the power grid, and the system regulation capability is a necessary condition for accepting large-capacity power input from outside the region and increasing the proportion of new energy consumption. Among many energy storage technologies, pumped storage is currently the most mature technology and the best power storage technology in terms of technical and economic indicators. However, the construction of pumped storage power stations in my country is relatively backward, and the installed capacity of pumped storage power stations accounts for less than 3% of the total installed capacity. At the same time, from the perspective of the types of newly built pumped storage power stations in Japan, the United States and other countries, the new pumped storage power station adopts the combination of doubly-fed motor and synchronous motor, which is in phase with the synchronous motor in conventional pumped storage power stations. It has higher stability and operating efficiency, and faster frequency regulation and voltage regulation.

In the central-eastern and southeastern regions of my country, the mountains and hills are remarkable, and there are many lakes and rivers. It has natural and rich natural conditions for the development of small and medium-sized hydropower. At the same time, there are a large number of urban clusters with developed economic conditions and strong demand for renewable energy. Based on this national condition, we will promote the development of distributed mountaintop pumped-storage power stations in the central, eastern and southeastern parts of my country according to local conditions. This kind of power station uses the existing valley reservoir as the lower reservoir (such as the Three Gorges Reservoir, Qingjiang Geheyan Reservoir, Duhe Reservoir, etc.) According to the terrain characteristics, one side of the dam site can be built up to two sides of the dam site to form a new reservoir). In this way, a series of small and medium-sized pumped-storage power stations that are distributed along the river basin and can both pump water and generate electricity are formed. During the low-load period, a large number of wind-solar hydropower stations outside the area are purchased, and electricity is generated and sold to the surrounding cities during the high-load period, and the regional power grid peak regulation is implemented. Valley tuning and dynamic optimization scheduling. After technical improvement, it will be a very economical energy storage scheduling solution for large-scale grid systems that can consume large-scale renewable energy such as northwest wind power photovoltaic and southwest hydropower.

The so-called generator-electric system refers to a generator-motor set in which the generator can be used as a water pump motor and a hydroelectric generator. When the power consumption of the power system is low, the unit is used as the pump operation mode, and the excess power of the power system is used to lift the water stored in the lower reservoir to the upper reservoir, which plays the role of filling the valley for power consumption. When the power system is in peak load period and there may be insufficient power, the water in the upper reservoir can be introduced into the lower reservoir unit, and the unit operates as a power generation mode, which plays a role in peak regulation of the power system. The unit can be used as both a hydroelectric generator and a water pump motor, which can not only provide electricity, but also serve as an electrical load. This is a significant difference between a power-generating electric pumped-storage system and a conventional pumped-storage system.

At present, there are two main types of variable-speed pumped-storage units, one is the synchronous power generation pumped-storage unit, and the other is the doubly-fed pumped-storage unit. However, both of the above have significant disadvantages. The synchronous power generation pumped-storage unit needs to be equipped with a full-power controller. Due to the large capacity of the single-unit unit of the pumped-storage power station, the cost of the entire system is high. The doubly-fed pumped-storage unit has brushes and slip ring devices, and its rotor components have high maintenance costs and poor safety and reliability.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a brushless doubly-fed power generation electric system for a distributed mountaintop pumped-storage power station in order to solve the above problems.

The present invention realizes above-mentioned purpose through following technical scheme:

The present invention includes a drainage pipe, a water pumping pipe, an upper storage reservoir, a lower storage reservoir, and a brushless doubly-fed power generation and electric system. Between the water inlets, the water outlet of the lower reservoir is connected with the water inlet of the upper reservoir, the power generation drive end of the brushless doubly-fed power generation electric system is connected in the drain pipe, the brushless The water pumping end of the doubly-fed power generation electric system is connected to the water suction pipe, and a plurality of sets of the brushless doubly-fed electric power generation system are arranged between the drainage pipe and the water suction pipe.

Further, the brushless doubly-fed power generation electric system is composed of a hydraulic turbine, a brushless doubly-fed motor, a pump, a transmission, and a transmission wheel. The rotating shaft of the electric motor is connected, the suction pump is arranged on the suction pipe, the other end of the rotating shaft of the brushless doubly-fed motor is connected with the transmission, and the output shaft of the transmission is connected with the water pump through the transmission wheel. drive shaft connection.

Further, the brushless doubly-fed motor includes a brushless doubly-fed motor and a control system capable of four-quadrant operation, and two sets of three-phase symmetrical independent sets of different pole pairs and not directly coupled to each other are distributed on the stator of the brushless doubly-fed motor. Windings, one set of windings is connected to the power grid, the other set of windings is connected to the control system, and the control system is connected to the power grid.

Preferably, the number of pole pairs of the brushless doubly-fed machine is 10 to 50, and the rotor adopts a winding type and a wave winding structure. The transmission has a gear ratio of 1:4 to 1:50. The suction pump is a reciprocating pump or a centrifugal pump.

The beneficial effects of the present invention are:

The invention is a brushless doubly-fed power generation electric system of a distributed mountain top pumped storage power station. Compared with the prior art, the invention can realize the four-quadrant control operation of variable speed constant voltage constant frequency and variable frequency speed regulation, and its control system capacity It can also realize flexible control of active and reactive power under the vector control strategy, with little interference to the power grid, and can play the role of active and reactive power compensation. At the same time, the motor itself has no slip rings and brushes, which not only reduces the motor It also improves the safety and reliability of system operation and reduces maintenance costs.

Description of drawings

Fig. 1 is the structural representation of the present invention;

FIG. 2 is a schematic structural diagram of the brushless doubly-fed generator electric system of the present invention.

In the picture: 1-drainage pipe, 2-pumping pipe, 3-upper reservoir, 4-lower reservoir, 5-brushless doubly-fed electric system, 51-turbine, 52-brushless doubly-fed motor, 53 -Water pump, 54-transmission, 55-drive wheel.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings:

As shown in FIG. 1 : the present invention includes a drainage pipe 1, a water pumping pipe 2, an upper storage reservoir 3, a lower storage reservoir 4, and a brushless double-fed power generation and electric system 5. The drainage pipe 1 is arranged on the upper storage reservoir. Between the water outlet of the reservoir 3 and the water inlet of the lower reservoir 4, the water outlet of the lower reservoir 4 is connected with the water inlet of the upper reservoir 3, and the brushless double-fed electric generator The power generation drive end of the system 5 is connected in the drain pipe 1 , and the suction end of the brushless double-fed power generation and electric system 5 is connected to the suction pipe 2 between the drain pipe 1 and the suction pipe 2 . A plurality of groups of the brushless doubly-fed generator-electric systems 5 are provided.

Further, the brushless doubly-fed power generation and electric system 5 is composed of a water turbine 51, a brushless doubly-fed motor 52, a water pump 53, a transmission 54, and a transmission wheel 55. The water turbine 51 is arranged in the drainage pipe 1, and the The water turbine 51 is connected with the rotating shaft of the brushless doubly-fed motor 52 through the rotating shaft, the suction pump 53 is arranged on the suction pipe 2, and the other end of the rotating shaft of the brushless doubly-fed motor 52 is connected with the transmission 54, The output shaft of the transmission 54 is connected to the drive shaft of the water pump 53 through the transmission wheel 55 .

When the motor operates as a generator, the turbine 51 drives the brushless doubly-fed motor 52 to convert potential energy into electrical energy and transmit it to the power grid; when the brushless doubly-fed motor operates as a motor, the brushless doubly-fed motor drives the suction pump connected to the transmission to The electrical energy is converted into the potential energy of water, and the water in the lower storage reservoir is pumped to the upper storage reservoir.

Further, the brushless doubly-fed motor includes a brushless doubly-fed motor and a control system capable of four-quadrant operation, and two sets of three-phase symmetrical independent sets of different pole pairs and not directly coupled to each other are distributed on the stator of the brushless doubly-fed motor. Windings, one set of windings is connected to the power grid, the other set of windings is connected to the control system, and the control system is connected to the power grid.

Preferably, the number of pole pairs of the brushless doubly-fed machine is 10 to 50, and the rotor adopts a winding type and a wave winding structure. The transmission has a gear ratio of 1:4 to 1:50. The suction pump is a reciprocating pump or a centrifugal pump.

As shown in Figures 1 and 2, when the device of the present invention is in the pumped storage state, the brushless doubly-fed motor 52 connected to the power grid drives the rotating shaft to rotate, and after the speed is increased through the transmission 54, the connecting shaft passes through the transmission wheel 55 to drive the pumping The water pump 53 works, and the water flow is pumped from the lower storage reservoir 2 to the upper storage reservoir 1 for storage. When the device of the present invention is in the state of discharging water and generating electricity, the upper storage reservoir discharges water downward through the drain pipe 1, drives the hydraulic turbine 51, and drives the brushless doubly-fed motor 52 to generate electricity, and the tail water flows to the lower storage reservoir 2. According to the peak and valley period of the power, The state of the pumped-storage power generation device is continuously adjusted to meet the electricity demand.

The foregoing has shown and described the basic principles and main features of the present invention and the advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above-mentioned embodiments, and the descriptions in the above-mentioned embodiments and the description are only to illustrate the principle of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have Various changes and modifications fall within the scope of the claimed invention. The claimed scope of the present invention is defined by the appended claims and their equivalents.

Claims (6)

1. A brushless doubly-fed power generation electric system of a distributed mountain top pumped storage power station is characterized in that: comprising a drain pipe, a pumping pipe, an upper storage reservoir, a lower storage reservoir, and a brushless double-fed power generation electric system, so The drain pipe is arranged between the drain outlet of the upper reservoir and the water inlet of the lower reservoir, the drain outlet of the lower reservoir is connected with the water inlet of the upper reservoir, and the The power generation drive end of the brushless doubly-fed power generation and electric system is connected in the drain pipe, the suction end of the brushless double-fed power generation and electric system is connected to the water suction pipe, and the drainage pipe and the water suction pipe are arranged between A plurality of groups of the brushless doubly-fed power generation electric systems. 2. The brushless doubly-fed power generation electric system of the distributed mountain top pumped-storage power station according to claim 1, characterized in that: the brushless doubly-fed electric power generation system is composed of a hydraulic turbine, a brushless doubly-fed motor, a water pump, It is composed of a transmission and a transmission wheel. The water turbine is arranged in the drainage pipe. The water turbine is connected to the rotation shaft of the brushless doubly-fed motor through a rotating shaft. The suction pump is arranged on the suction pipe. The other end of the rotating shaft of the feeder is connected with the transmission, and the output shaft of the transmission is connected with the drive shaft of the water pump through the transmission wheel. 3. The brushless doubly-fed power generation electric system of the distributed mountain top pumped-storage power station according to claim 2, wherein the brushless doubly-fed motor comprises a brushless doubly-fed motor and a control capable of four-quadrant operation In the system, two sets of three-phase symmetrical independent windings with different pole pairs and not directly coupled to each other are distributed on the stator of the brushless doubly-fed motor. 4. The brushless doubly-fed power generation electric system of the distributed mountain top pumped storage power station according to claim 2 or 3, characterized in that: the number of pole pairs of the brushless doubly-fed motor is 10 to 50, and the rotor adopts winding type and wave winding structure. 5 . The brushless doubly-fed power generation electric system of the distributed mountain top pumped storage power station according to claim 2 , wherein the transmission ratio of the transmission is 1:4 to 1:50. 6 . 6 . The brushless doubly-fed power generation electric system of the distributed mountain top pumped-storage power station according to claim 2 , wherein the pumping pump is a reciprocating pump or a centrifugal pump. 7 .

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