COOLING AND LUBRICATING SYSTEM OF SPEED-UP GEAR BOX OF WIND POWER UNIT AND LOW-TEMPERATURE STARTING METHOD THEREOF

Abstract

A lubricant cooler, a cooling and lubricating system of a speed-up gear box, a wind power unit and a low-temperature starting method of the wind power unit. The lubricant cooler includes a radiating plate and a one-way valve arranged on a lubricant conveying pipeline, wherein the radiating plate and the one-way valve are arranged in parallel, and the one-way valve and/or the lubricant conveying pipeline in communication with the one-way valve are integrated on the radiating plate. The lubricant cooler can solve the problem that, when the wind power unit is started at a low temperature, the cooling and lubricating system of the speed-up gear box causes the shut-down of the wind power unit because the lubricant blocks the radiating plate.

Claims

1. A lubricant cooler, comprising a heat dissipation plate and a one-way valve configured to be arranged in a lubricant conveying pipeline, wherein the heat dissipation plate and the one-way valve are connected in parallel, and the one-way valve or the lubricant conveying pipeline in communication with the one-way valve is integrated on the heat dissipation plate.

2. The lubricant cooler according to claim 1, wherein the one-way valve or the lubricant conveying pipeline in communication with the one-way valve is integrated inside the heat dissipation plate.

3. A cooling and lubricating system of a speed-increasing gearbox, equipped with a lubricant cooler, and the lubricant cooler comprises a heat dissipation plate and a one-way valve configured to be arranged in a lubricant conveying pipeline, wherein the heat dissipation plate and the one-way valve are connected in parallel, and the one-way valve or the lubricant conveying pipeline in communication with the one-way valve is integrated on the heat dissipation plate.

4. The cooling and lubricating system of the speed-increasing gearbox according to claim 3, further comprising a double-speed lubricant pump, an overflow valve, a filter, a temperature control valve, a lubricant dispenser, a heater, and a speed-increasing gearbox, wherein an inlet of the double-speed lubricant pump is in communication with the speed-increasing gearbox, and an outlet of the double-speed lubricant pump is in communication with the speed-increasing gearbox via a first pipeline, and the overflow valve is arranged in the first pipeline; the outlet of the double-speed lubricant pump is in communication with an inlet of the filter via a second pipeline, and an outlet of the filter is in communication with the lubricant dispenser via a third pipeline and a fourth pipeline respectively, the lubricant cooler is arranged in the third pipeline, and the temperature control valve is arranged in the fourth pipeline, and the temperature control valve is a normally open temperature control valve; and a valve port of the temperature control valve is closed gradually when a temperature of a lubricant is higher than a first preset temperature t1, and is completely closed till the temperature of the lubricant reaches a second preset temperature t2; and the lubricant dispenser is in communication with the speed-increasing gearbox.

5. A wind turbine generator system, equipped with the cooling and lubricating system of the speed-increasing gearbox according to claim 4.

6. The wind turbine generator system according to claim 5, comprising a nacelle housing, wherein the nacelle housing has an air inlet and an air outlet for ventilation of the cooling and lubricating system of the speed-increasing gearbox, a cover plate capable of being open and close is arranged at the air inlet, and the cover plate of the air inlet is closed in seasons with a low temperature.

7. A low-temperature starting method of the wind turbine generator system according to claim 5, wherein in low-temperature starting, the following steps are performed: S1) first heating a lubricant in a lubricant tank by a heater of the speed-increasing gearbox; S2) starting the double-speed lubricant pump to work first in a low speed state, and then pumping the lubricant from the lubricant tank of the speed-increasing gearbox to the cooling and lubricating system, wherein in this case, the lubricant cannot flow through the cooler under the action of a pressure of the lubricant pump, and the lubricant enters the filter and flows back to the speed-increasing gearbox through the fourth pipeline; and S3) connecting the wind turbine generator system to an electrical grid to generate power, to allow the temperature of the lubricant in the speed-increasing gearbox to rise gradually, to gradually close the temperature control valve in the fourth pipeline, and to allow the pressure at an inlet of the cooler in the third pipeline to continuously increase, to open the one-way valve in the cooler, to further allow part of the lubricant with a high temperature to flow from the fourth pipeline side back to the speed-increasing gearbox via the one-way valve connected in parallel with the heat dissipation plate, wherein, when the lubricant with a high temperature flows through the one-way valve, heat is transmitted to the heat dissipation plate from the one-way valve, to heat the lubricant inside the heat dissipation plate, to finally allow the lubricant to flow through the whole heat dissipation plate, to enable the cooling and lubricating system of the speed-increasing gearbox to work normally, to achieve normal starting of the wind turbine generator system at a low temperature.

8. The cooling and lubricating system of the speed-increasing gearbox according to claim 3, wherein the one-way valve or the lubricant conveying pipeline in communication with the one-way valve is integrated inside the heat dissipation plate.

9. The cooling and lubricating system of the speed-increasing gearbox according to claim 8, further comprising a double-speed lubricant pump, an overflow valve, a filter, a temperature control valve, a lubricant dispenser, a heater, and a speed-increasing gearbox, wherein an inlet of the double-speed lubricant pump is in communication with the speed-increasing gearbox, and an outlet of the double-speed lubricant pump is in communication with the speed-increasing gearbox via a first pipeline, and the overflow valve is arranged in the first pipeline; the outlet of the double-speed lubricant pump is in communication with an inlet of the filter via a second pipeline, and an outlet of the filter is in communication with the lubricant dispenser via a third pipeline and a fourth pipeline respectively, the lubricant cooler is arranged in the third pipeline, and the temperature control valve is arranged in the fourth pipeline, and the temperature control valve is a normally open temperature control valve; and a valve port of the temperature control valve is closed gradually when a temperature of a lubricant is higher than a first preset temperature t1, and is completely closed till the temperature of the lubricant reaches a second preset temperature t2; and the lubricant dispenser is in communication with the speed-increasing gearbox.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0030] For more clearly illustrating embodiments of the present application or the technical solutions in the conventional technology, drawings referred to describe the embodiments or the conventional technology will be briefly described hereinafter. Apparently, the drawings in the following description are only examples of the present application, and for the person skilled in the art, other drawings may be obtained based on the drawings without any creative efforts.

[0031] FIG. 1 is a structural view showing a heat dissipation plate and a one-way valve connected in parallel in a lubricant cooler according to the present application, and arrows in the figure indicate flowing directions of the lubricant;

[0032] FIG. 2 is a schematic diagram of a cooling and lubricating system of a speed-increasing gearbox according to an embodiment of the present application; and

[0033] FIG. 3 is a schematic view showing the structure of a nacelle housing in the wind turbine generator system according to the present application.

DETAILED DESCRIPTION

[0034] The technical solutions in the embodiments of the present application will be described clearly and completely hereinafter in conjunction with the drawings in the embodiments of the present application. Apparently, the described embodiments are only one part of the embodiments of the present application, rather than all embodiments. Based on the embodiments in the present application, all of other embodiments, made by the person skilled in the art without any creative efforts, fall into the scope of the present application.

First Embodiment: Lubricant Cooler

[0035] As shown in FIG. 1, the lubricant cooler according to the present application includes a heat dissipation plate 7.2 and a one-way valve 7.1 configured to be arranged on a lubricant conveying pipeline. The heat dissipation plate 7.2 and the one-way valve 7.1 are connected in parallel, and the one-way valve 7.1 or the lubricant conveying pipeline 6 in communication with the one-way valve 7.1 is integrated on the heat dissipation plate 7.2. Preferably, the one-way valve 7.1 or the lubricant conveying pipeline 6 in communication with the one-way valve 7.1 is integrated inside the heat dissipation plate 7.2, to maximum the efficiency in transferring heat from the one-way valve 7.1 or from the lubricant conveying pipeline in communication with the one-way valve 7.1 to the heat dissipation plate 7.2. Preferably, the lubricant cooler further includes a cooling fan 7.3 for cooling and venting of the heat dissipation plate 7.2, to improve the heat dissipation efficiency of the heat dissipation plate 7.2. Of course, the cooler 7 may not include the cooling fan 7.3, and employs a natural convection cooling. The cooler 7 may further be applicable to other liquids with viscosity-temperature property similar to that of the lubricant of the speed-increasing gearbox of the wind turbine generator, and may be applicable to a liquid-air heat exchange and a liquid-liquid heat exchange. The heat dissipation plate and the one-way valve are connected in parallel, thus, the lubricant conveying pipeline 6 is divided into two branch conveying pipelines to allow the lubricant to flow through the heat dissipation plate and the one-way valve respectively. In normal operation, the pressure at an inlet of the heat dissipation plate cannot open the one-way valve, and when the heat dissipation plate is blocked since the lubricant in the heat dissipation plate has a low temperature, the external lubricant flows through the one-way valve, thus the lubricant with a high temperature flowing through the one-way valve can transmit heat to the lubricant in the heat dissipation plate, and in turn clears the heat dissipation plate, which prevents shut-down of the machine caused when the heat dissipation plate is blocked by the lubricant with a low temperature. The lubricant cooler according to the present application can realize normal starting at the low temperature, and can address the issue that the wind turbine generator system is shutdown since the lubricant with a low temperature blocks the heat dissipation plate when the wind turbine generator system is started up at a low temperature.

Second Embodiment: Cooling and Lubricating System of the Speed-Increasing Gearbox, wind Turbine Generator System Using the Cooling and Lubricating System of the Speed-Increasing Gearbox, and Low-Temperature Starting Method of the Wind Turbine Generator System

[0036] The cooling and lubricating system of the speed-increasing gearbox according to the present application, as shown in FIGS. 1 and 2, includes a double-speed lubricant pump 1, an overflow valve 2, a filter 3 and a differential pressure sensor 4, a temperature control valve 5, a lubricant conveying pipeline 6, a lubricant cooler 7, a lubricant dispenser 10, a heater 11 and a speed-increasing gearbox 12. The cooler 7 preferably includes a one-way valve 7.1, a heat dissipation plate 7.2 and a cooling fan 7.3. The one-way valve 7.1 is integrated on the heat dissipation plate 7.2 by parallel connection, as shown in FIG. 1. Preferably, the cooling and lubricating system of the speed-increasing gearbox according to this embodiment may further include a pressure sensor 8 configured to measure the pressure of the lubricant flowing into the lubricant dispenser via the cooler, and a temperature sensor 9 configured to measure the temperature of the lubricant flowing into the lubricant dispenser via the temperature control valve. An inlet of the double-speed lubricant pump 1 is in communication with the speed-increasing gearbox 12, and an outlet of the double-speed lubricant pump 1 is in communication with the speed-increasing gearbox 12 via a first pipeline 13. The overflow valve 2 is arranged in the first pipeline 13. The outlet of the double-speed lubricant pump 1 is in communication with an inlet of the filter 3 via a second pipeline 14, and an outlet of the filter 3 is in communication with the lubricant dispenser 10 via a third pipeline 15 and a fourth pipeline 16 respectively. The lubricant cooler 7 is arranged in the third pipeline 15, and the temperature control valve 5 is arranged in the fourth pipeline 16, and the temperature control valve 5 is a normally open temperature control valve. When the temperature of the lubricant is higher than a first preset temperature t1, a valve port of the temperature control valve is closed gradually, and the valve port is completely closed till the temperature of the lubricant reaches a second preset temperature t2. The lubricant dispenser 7 is in communication with the speed-increasing gearbox 12.

[0037] In normal operation, the double-speed lubricant pump 1 starts to work at a low speed firstly, and the lubricant is pumped from a lubricant tank of the speed-increasing gearbox 12 to the cooling and lubricating system. If the cooling and lubricating system has faults such as blockage which causes the pressure at the outlet of the double-speed lubricant pump 1 to be higher than a system safety pressure, the overflow valve 2 opens, and the lubricant flows back to the speed-increasing gearbox 12 from the overflow valve 2 to achieve the function of protecting the system; otherwise, the lubricant flows into the filter 3. The lubricant flows back to the speed-increasing gearbox 12 via two paths after being filtered, and one path is through the temperature control valve 5 and the other path is through the cooler 7.

[0038] The temperature control valve 5 is open normally, and acts within the temperature interval [t1, t2]. When the temperature of the lubricant flowing through the temperature control valve 5 is lower than t1, the temperature control valve 5 is in an open state; and the valve port of the temperature control valve 5 is gradually closed when the temperature of the lubricant is equal to or greater than t1, and is completely closed till the temperature of the lubricant reaches the temperature t2. When the temperature of the lubricant is lower than t1, most part of the lubricant flows back to the speed-increasing gearbox 12 through the temperature control valve 5 and the lubricant dispenser 10, and the rest of the lubricant flows back to the speed-increasing gearbox 12 through the cooler 7 and the lubricant dispenser 10. When the temperature of the lubricant is higher than t1, the lubricant flowing through the heat dissipation plate of the cooler 7 gradually increases, to reduce the temperature of the lubricant. When the temperature of the lubricant is higher than t3, the cooling fan 7.3 of the cooler starts, to further increase the cooling power of the heat dissipation plate of the cooler 7. When the temperature of the lubricant is higher than t2, the temperature control valve is closed completely, and all the lubricant flows through the cooler 7 to be cooled, and t3 is within the temperature interval [t1, t2].

[0039] The wind turbine generator system according to the present application includes a rotor 23, a nacelle 22 and a tower 21. For ensuring the starting performance of the cooling and lubricating system of the speed-increasing gearbox at a low temperature, the cooler 7 is arranged in the nacelle 22 of the wind turbine generator system at a position close to the speed-increasing gearbox 12, and air flows in through an air inlet 18 at the bottom of a nacelle housing 17, and flows out from an air outlet 19. For meeting the ventilation requirement of the nacelle, a vent 20 is provided at a tail portion of the nacelle housing. A cover plate capable of being opened and closed is provided at the air inlet 18. The cover plate at the air vent is open in normal conditions, and the cover plate closes the air inlet 18 in seasons with a low temperature, thus, on the premise that the ventilation requirement of the cooling and lubricating system of the speed-increasing gearbox is met, external air with a low temperature is restricted from entering the nacelle, which reduces the dropping speed of the temperature in the nacelle when the system is on standby or stopped, and increases the rising speed of the temperature in the nacelle in the low-temperature starting, reduces convection and heat transfer between the components such as the speed-increasing gearbox, and ensures the heating effects of the speed-increasing gearbox, the cooling pipeline, the generator and the like in the low-temperature starting.

[0040] The low-temperature starting method of the wind turbine generator system includes the following steps. First, the lubricant in the lubricant tank is heated by the heater 11 of the speed-increasing gearbox to a certain temperature. The double-speed lubricant pump 1 starts at a low speed. Due to the low temperature, the lubricant at this time cannot flow through the heat dissipation plate 7.2, and all the lubricant flows back to the speed-increasing gearbox 12 through the temperature control valve 5 and the lubricant dispenser 10. As the wind turbine generator system is connected to the electrical grid to generate power, the temperature of the lubricant in the speed-increasing gearbox gradually rises, and when the temperature is greater than t1, the temperature control valve 5 is gradually closed, which allows the pressure at an inlet end of the cooler 7 to gradually increase and in turn open the one-way valve 7.1, thus part of the lubricant with a high temperature flows back to the speed-increasing gearbox through the one-way valve 7.1 and the lubricant dispenser 10, and the rest most part of the lubricant flows back to the speed-increasing gearbox through the temperature control valve 5 and the lubricant dispenser 10. When the lubricant with a high temperature flows through the one-way valve 7.1, heat is transmitted from the one-way valve 7.1 to the heat dissipation plate 7.2, to allow the temperature of the side, close to one-way valve 7.1, of the heat dissipation plate 7.2 to rise gradually, and thus allowing part of the lubricant with a high temperature at the cooler side to flow through this region of the heat dissipation plate 7.2, and further gradually transmit heat to the whole heat dissipation plate 7.2, to finally allow the lubricant to flow through the whole heat dissipation plate 7.2, thereby allowing the cooling and lubricating system to operate normally.

[0041] Finally, it is to be noted that, the above embodiments are only intended to illustrate technical solutions of the present application rather than limit the present application. Though the present application is described in detail with reference to the preferred embodiments, it should be appreciated by the person skilled in the art that, modifications or equivalent substitutions may be made to the technical solutions of the present application without departing from the purpose and scope of the technical solutions of the present application, and these modifications or equivalent substitutions are also deemed to fall into the scope of the present application defined by the claims.