1. Field of Invention
The present invention relates to the field of power generation equipment technology, specifically to an Organic Rankin Cycle (ORC) power generation system, and meanwhile to a semi-sealed or fully sealed screw expansion power generation device.
2. Description of Related Arts
Referring to
A low-temperature and low-pressure liquid refrigerant is pressurized in the liquid pump 4′, and then enters the evaporator 3′ to be evaporated through heating until the refrigerant becomes an overheated gas (high temperature and high pressure). The overheated gas enters the expander 1′ to work through expansion, so as to drive the generator 2′ to generate power. After working, the low-temperature and low-pressure gas enters the condenser 5′ and is condensed to liquid, and then flows back into the liquid pump 4′, thus completing a cycle.
Existing expanders used in the ORC are semi-sealed centrifugal expanders and open-type screw expanders. The open-type screw expander is connected to a generator at an output shaft end through a shaft seal, and a defect thereof is that a refrigerant will leak through the shaft seal.
Meanwhile, in a cascade ORC cycle (or other application scenarios), a temperature at the end of the expansion may be very high, so cooling the generator by exhaust of the expansion becomes impractical. A cooling problem of the generator in the semi-sealed or fully sealed screw expansion power generation device needs to be solved.
The technical problem to be solved in the present invention is to provide a semi-sealed or fully sealed screw expansion power generation device, which can prevent leakage of a refrigerant when a screw expansion generator generates power, and at the same time can cool the generator in the screw expansion power generation device.
In order to solve the above technical problem, the present invention adopts the following technical solution.
A semi-sealed or fully sealed screw expansion power generation device is provided, wherein the power generation device comprises a semi-sealed or fully sealed shell, the shell comprises an expander cavity and a generator cavity; the expander cavity is not in communication with the generator cavity; a screw expander is disposed in the expander cavity, and a generator is disposed in the generator cavity; a rotor of the screw expander is fixedly connected to a rotor of the generator; the power generation device drives the generator to generate power through rotation of the rotor of the screw expander; a liquid refrigerant injection inlet and a refrigerant outlet are disposed on the generator cavity; and the generator is cooled through evaporation of the liquid refrigerant.
As a preferential solution of the present invention, the screw expander comprises a male rotor and a female rotor, and a shaft of the male rotor is fixedly connected to the rotor of the generator.
As a preferential solution of the present invention, a first male rotor bearing is disposed at an end of the male rotor away from the rotor of the generator, and female rotor bearings are separately disposed at two ends of the female rotor.
As a preferential solution of the present invention, the male rotor comprises a rotor part and a connection part which are integrally designed, and the rotor part coordinates with the female rotor; the connection part extends into the generator; the expander cavity and the generator cavity are isolated from each other through an isolation mechanism, so that a hole is formed between the expander cavity and the generator cavity; the connection part passes through the hole and enters the generator cavity, and an end of the connection part away from the rotor part is fixedly connected to the rotor of the generator.
As a preferential solution of the present invention, a second male rotor bearing is disposed at the connection part and between the rotor part of the male rotor and the rotor of the generator; the first male rotor bearing, the second male rotor bearing and the female rotor bearings are separately disposed in the shell through a support mechanism disposed in the shell; the connection part and an end of the second male rotor bearing closest to the rotor of the generator are sealed through a shaft seal.
As a preferential solution of the present invention, a suction inlet and an exhaust outlet of the screw expander are disposed on the expander cavity.
As a preferential solution of the present invention, the generator is a synchronous generator or an asynchronous generator.
The present invention has the following beneficial effects: the semi-sealed or fully sealed screw expansion power generation device and the ORC power generation system using the screw expansion power generation device provided in the present invention can prevent the refrigerant from leaking through the shaft seal when the screw expansion generator generates power. Meanwhile, the generator can be effectively cooled. The cooling problem of the generator in the screw expansion power generation device can be solved even in a cascade ORC cycle or in a single cycle where the exhaust of the expander is of a very high temperature.
Exemplary embodiments of the present invention are described in detail with reference to the accompanying drawings below.
Referring to
Referring to
The screw expander and the generator 101 are integrally disposed. A rotor of the screw expander is fixedly connected to a rotor of the generator, and the power generation device 1 drives the generator 101 to generate power through rotation of the rotor of the screw expander.
Further referring to
In conclusion, in the semi-sealed or fully sealed screw expansion power generation device and the ORC power generation system using the above screw expansion power generation device provided in the present invention, the screw expansion power generation device is semi-sealed or fully sealed; the screw expander and the generator are disposed in the shell as a whole, thereby preventing leakage of the refrigerant through the shaft seal when the screw expansion generator generates power. Meanwhile, the generator can be cooled effectively. Even in a cascade ORC, or even when an exhaust temperature of the expander is very high in a single cycle, the cooling problem of the generator in the screw expansion power generation device can be solved.
In this embodiment, a rotor that drives the generator to generate power may be a female rotor.
Herein, the description and application of the present invention are illustrative, and the scope of the present invention is not intended to be limited to the above embodiments. Variations and changes to the embodiments disclosed herein are possible. Replacement made to the embodiments and equivalent parts are well-known to persons skilled in the art. It should be known to persons skilled in the art that, the present invention can be implemented in other forms, structures, arrangements, ratios and through other components, materials, and parts without departing from the script or essential features of the present invention. Other variations and changes may be made to the embodiments disclosed herein without departing from the scope and script of the present invention.
Number | Date | Country | Kind |
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201010548665.8 | Nov 2010 | CN | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/CN2010/079285 | 11/30/2010 | WO | 00 | 1/28/2013 |