Variable frequency generator

Abstract

The variable-frequency generator comprises an engine, a fan assembly, a stator and rotor assembly driven by the engine and a frequency converter electrically connected with the stator and rotor assembly, a frequency converter cover is arranged on the outer side of the frequency converter, the fan assembly comprises blades and a fan cover, and the fan cover is connected with the frequency converter cover through a ventilation pipeline; each blade comprises a partition plate, a first cooling fin set and a second cooling fin set, and the first cooling fin set and the second cooling fin set are located on the two sides of the partition plate correspondingly. The first cooling fin set and the side, connected with the frequency converter cover, of the fan cover form a first cooling cavity, and the second cooling fin set and the other side of the fan cover form a second cooling cavity. According to the invention, the second cooling cavity is used for cooling the stator and rotor assembly, the first cooling cavity is used for cooling the frequency converter, and mutual influence of two groups of cooling air is avoided, so that the cooling effect on the frequency converter and the stator and rotor assembly can be ensured, and the service life of the generator is prolonged.

Description

Technical Field

[0001] The invention relates to a variable frequency generator, in particular to a variable frequency generator with a cooling mechanism. Background Art

[0002] As a generator that can change frequency, the engine operating speed can vary within a large range, so it can be well matched with the generator to achieve the purpose of saving fuel. During operation, the engine, stator and rotor unit and frequency conversion controller will generate a certain amount of heat. If the heat cannot be dissipated in time, the power of the generator set will decrease in short-term use, and the life of the generator set will be shortened in long-term use.

[0003] Chinese patent document CN102035304B discloses a digital variable frequency generator set, which discloses a technology that the crankshaft of the engine set rotates with the fan 11, and the cooling airflow flows in from the first through hole 103 on the control panel 1 and / or the second through hole 501 provided on the side wall of the air guide cover 5, and is forced to pass through the inverter cooling cavity 35 formed by the air guide frame baffle 203 and the inverter heat dissipation teeth 301, taking away the heat on the inverter heat sink 3, so as to cool the inverter 4. The airflow coming out of the inverter cooling cavity 35 flows through the hose 6 and the joint 7 under the guidance of the air guide groove 201 of the air guide frame 2, and flows into the generator cooling protection frame 8 to cool the generator 12.

[0004] The prior art has the following disadvantages: the digital variable frequency generator set has the problem of insufficient generator cooling during operation, especially under high load operation, insufficient generator cooling will still cause power reduction and shorten the life of the generator set. Summary of the invention

[0005] In order to solve the technical problem of insufficient generator cooling in the prior art, the present invention provides a variable frequency generator, comprising an engine, a fan assembly, a stator-rotor assembly driven by the engine and a frequency converter electrically connected to the stator-rotor assembly, a frequency converter cover is arranged on the outside of the frequency converter, the fan assembly comprises blades and a fan cover, and the fan cover is connected to the frequency converter cover through a ventilation duct; wherein: the blades comprise a partition plate, a first cooling fin group and a second cooling fin group, the first cooling fin group and the second cooling fin group are respectively located on both sides of the partition plate; the first cooling fin group and the fan cover are connected to one side of the frequency converter cover to form a first cooling cavity, and the second cooling fin group and the other side of the fan cover form a second cooling cavity.

[0006] After analyzing the problem of insufficient cooling in the prior art, it was found that in the prior art, the airflow entering the generator for cooling will first pass through the inverter. After the airflow passes through the inverter, the temperature rises and becomes hot air. Finally, the airflow entering the generator for cooling is essentially hot air with a high temperature, which leads to the problem of insufficient cooling. Especially when the generator set is running at high load, the higher the temperature of the inverter, the higher the temperature of the airflow entering the generator set, which seriously affects the cooling effect and forms a vicious cycle.

[0007] In this solution, two types of fin groups on the blades are used to form different cooling chambers, wherein the first cooling chamber can cool the inverter, and the second cooling chamber can cool the stator and rotor assembly. The two cooling chambers are used to cool the inverter and the stator and rotor assembly respectively, that is, separate airflows are used to cool the inverter and the stator and rotor assembly respectively, and there is no problem that the airflow during cooling is the temperature after heating, thereby ensuring the cooling effect of the inverter and the stator and rotor assembly, and thus extending the service life of the generator set.

[0008] Preferably, the fan cover is provided with an air outlet along the tangential direction, and the air outlet is connected with the first cooling cavity and the second cooling cavity.

[0009] Preferably, a first air inlet connected to the first cooling cavity is provided on the fan cover on one side facing the first cooling fin group, and the first air inlet is connected to the inverter cover through a ventilation duct. In this solution, the provision of the first air inlet ensures a cooling effect on the inverter.

[0010] Preferably, the fan cover is provided with a first air outlet connected to the first cooling cavity along the tangential direction. In this solution, the design of the position of the first air outlet can improve the cooling efficiency.

[0011] Preferably, the engine is connected to a muffler, and the first air outlet is arranged toward the muffler. In this solution, after the air outlet is arranged toward the muffler, the airflow that has cooled the inverter is directed to the first air outlet and toward the muffler, and since the temperature of the muffler is very high, which is higher than the temperature of the airflow heated by the inverter, the airflow blowing toward the muffler can also cool the muffler.

[0012] Preferably, the blades are located on the side of the stator-rotor assembly facing the inverter. In this solution, arranging the blades on the side of the stator-rotor assembly facing the inverter can avoid mutual cooling of the stator-rotor assembly and the inverter, thereby ensuring the cooling effect of the stator-rotor assembly and the inverter.

[0013] Preferably, a second air inlet connected to the second cooling cavity is provided on one side of the fan cover facing the second cooling fin group. In this solution, the provision of the second air inlet ensures the cooling effect on the stator and rotor assembly.

[0014] Preferably, the fan cover is further provided with a second air outlet connected to the second cooling chamber along the tangential direction, and the second air outlet is arranged in parallel with the first air outlet.

[0015] Preferably, the first air outlet and the second air outlet are respectively arranged towards different positions of the muffler. In this solution, the arrangement of the first air outlet and the second air outlet towards different positions of the muffler can achieve a better cooling effect on the muffler.

[0016] The present invention has the following beneficial effects: 1. In the present invention, the second cooling chamber is used to cool the stator and rotor assembly, and the first cooling chamber is used to cool the frequency converter, so as to avoid the mutual influence of the two groups of cooling air, thereby ensuring the cooling effect of the frequency converter and the stator and rotor assembly and improving the service life of the generator.

[0017] 2. In the present invention, the muffler is also cooled, which can also extend the service life of the muffler. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A schematic diagram of an embodiment of a variable frequency generator of the present invention; Figure 2 for Figure 1 A top view of Figure 3 for Figure 1 Cross-sectional view①; Figure 4 for Figure 1 Cross-sectional view②. DETAILED DESCRIPTION

[0019] The following is further described in detail through specific implementation methods: 1. Definition Cooling fin assembly: includes multiple cooling fins.

[0020] 2. The reference numerals in the drawings of the specification include: engine 1, stator and rotor assembly 2, second cooling fin group 3, partition plate 4, first cooling fin group 5, first air inlet 7, fan cover 6, ventilation duct 8, inverter cover 9, inverter 10, muffler 11, first air outlet 12, second air inlet 13, second air outlet 14.

[0021] The embodiment is basically as shown in the attached Figure 1-Figure 4As shown: a variable frequency generator, including an engine 1, a muffler 11, a fan assembly, a stator-rotor assembly 2 driven by the engine 1, and a frequency converter 10 electrically connected to the stator-rotor assembly 2, a frequency converter cover 9 is provided on the outside of the frequency converter 10, the fan assembly includes blades and a fan cover 6, a gap is provided between the inner wall of the fan cover 6 and the blades, the blades are located on the side of the stator-rotor assembly 2 facing the frequency converter 10, and the fan cover 6 is connected to the frequency converter cover 9 through a ventilation duct 8. The stator-rotor assembly 2 includes a stator and a rotor, and the fan assembly is connected to the rotor. In other embodiments, the blades can also be arranged on the crankshaft of the engine 1 on the side of the stator-rotor assembly 2 opposite to the engine 1.

[0022] The blades include a partition plate 4, a first cooling fin group 5 and a second cooling fin group 3. The first cooling fin group 5 and the second cooling fin group 3 are respectively located on both sides of the partition plate 4. Specifically, the first cooling fin group 5 is located on the right side of the partition plate 4, and the second cooling fin group 3 is located on the left side of the partition plate 4. A second air inlet 13 connected to the second cooling cavity is provided on the side of the fan cover 6 facing the second cooling fin group 3. The second cooling fin group 3 and the left side of the fan cover 6 form a second cooling cavity. A first air inlet 7 connected to the first cooling cavity is provided on the side of the fan cover 6 facing the first cooling fin group 5. The first air inlet 7 is connected to the inverter cover 9 through the ventilation duct 8. The first cooling fin group 5 and the right side of the fan cover 6 form a first cooling cavity.

[0023] The fan cover 6 is provided with a first air outlet 12 connected to the first cooling chamber and a second air outlet 14 connected to the second cooling chamber along the tangential direction. The first air outlet 12 and the second air outlet 14 are arranged in parallel. The first air outlet 12 and the second air outlet 14 are arranged toward different positions of the muffler 11 to cool different positions of the muffler 11. The first air outlet 12 and the second air outlet 14 are located on one side of the first air inlet 7 and the second air inlet 13.

[0024] The specific implementation process is as follows: when the variable frequency generator is running, the fan assembly rotates, and the airflow near the second air inlet 13 is sucked into the second cooling chamber through the second air inlet 13 to cool the stator and rotor assembly 2, and then blown out from the second air outlet 14; the airflow near the inverter 10 is sucked into the inverter cover 9 to cool the inverter 10, and then sucked into the first cooling chamber of the fan cover 6 through the ventilation duct 8 and the first air inlet 7, and then blown out through the first air outlet 12. The airflow blown out from the first air outlet 12 and the second air outlet 14 cools the muffler 11.

[0025] The above is only an embodiment of the present invention. The common sense such as the known specific structure and characteristics in the scheme is not described in detail here. The ordinary technicians in the relevant field know all the common technical knowledge in the technical field of the invention before the application date or priority date, can obtain all the existing technologies in the field, and have the ability to apply the conventional experimental means before that date. The ordinary technicians in the relevant field can improve and implement this scheme in combination with their own abilities under the enlightenment given by this application. Some typical known structures or known methods should not become obstacles for ordinary technicians in the relevant field to implement this application. It should be pointed out that for those skilled in the art, without departing from the structure of the present invention, several deformations and improvements can be made, which should also be regarded as the protection scope of the present invention, which will not affect the effect of the implementation of the present invention and the practicality of the patent. The protection scope required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A variable frequency generator, comprising an engine, a fan assembly, a stator and rotor assembly driven by the engine, and a frequency converter electrically connected to the stator and rotor assembly, wherein a frequency converter cover is arranged outside the frequency converter, the fan assembly comprises blades and a fan cover, and the fan cover is connected to the frequency converter cover through a ventilation duct; characterized in that: The blades include a partition plate, a first cooling fin group and a second cooling fin group, wherein the first cooling fin group and the second cooling fin group are respectively located on both sides of the partition plate; the first cooling fin group and the fan cover are connected to one side of the inverter cover to form a first cooling cavity, and the second cooling fin group and the other side of the fan cover form a second cooling cavity.

2. The variable frequency generator according to claim 1, characterized in that: A first air inlet connected to the first cooling cavity is provided on the fan cover at one side facing the first cooling fin group, and the first air inlet is connected to the inverter cover through the ventilation duct.

3. The variable frequency generator according to claim 1 or 2, characterized in that: The fan cover is provided with a first air outlet connected to the first cooling cavity along a tangential direction.

4. The variable frequency generator according to claim 3, characterized in that: The engine is connected to a muffler, and the first air outlet is arranged toward the muffler.

5. The variable frequency generator according to claim 4, characterized in that: The blade is located on a side of the stator-rotor assembly facing the frequency converter.

6. The variable frequency generator according to claim 5, characterized in that: A second air inlet communicating with the second cooling cavity is provided on one side of the fan cover facing the second cooling fin group.

7. The variable frequency generator according to claim 6, characterized in that: The fan cover is also provided with a second air outlet connected to the second cooling chamber along the tangential direction, and the second air outlet is arranged in parallel with the first air outlet.

8. The variable frequency generator according to claim 7, characterized in that: The first air outlet and the second air outlet are respectively arranged towards different positions of the muffler.

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