阅读说明：本技术 一种周向多电机驱动的环形电力推进器 (Annular electric propeller driven by multiple circumferential motors ) 是由 郑锐聪 邱湘瑶 肖燕燕 刘福超 于 2020-04-27 设计创作，主要内容包括：本发明涉及一种周向多电机驱动的环形电力推进器,包括：壳体、电机驱动单元、磁液复合悬浮轴承系统和螺旋桨,所述电机驱动单元包括：公共转子组件和多个定子组件,所述公共转子组件设置于所述壳体的内侧,所述多个定子组件沿所述壳体周向间隔环布于所述壳体内且与所述公共转子组件形成多定子-单转子副。本发明结构简单、推进效率高、振动噪声低、安全性和冗余度高、启动电流低,可应用在电动船舶上,尤其适合于内河和湖泊浅吃水环境限制的电动船舶。(The invention relates to a circumferential multi-motor driven annular electric propeller, which comprises: casing, motor drive unit, compound suspension bearing system of magnetic-liquid and screw, motor drive unit includes: the public rotor assembly is arranged on the inner side of the shell, and the stator assemblies are circumferentially distributed in the shell along the shell and form a multi-stator-single-rotor pair with the public rotor assembly. The invention has simple structure, high propulsion efficiency, low vibration noise, high safety and redundancy and low starting current, can be applied to electric ships, and is particularly suitable for electric ships with limited shallow draught environment in inland rivers and lakes.)

1. A circumferential multi-motor driven annular electric thruster, comprising: a shell, a motor driving unit, a magnetic-liquid composite suspension bearing system and a propeller, wherein,

the motor driving unit includes: the public rotor assembly is arranged on the inner side of the shell, and the stator assemblies are annularly distributed in the shell along the circumferential direction of the shell and form a multi-stator-single-rotor pair with the public rotor assembly;

the magnetic-liquid composite suspension bearing system is connected with the public rotor assembly and used for enabling the public rotor assembly to be in a suspension state; the propellers are connected with the common rotor assembly.

2. The annular electric propeller of claim 1, wherein the motor driving unit further comprises end flanges, the end flanges are respectively disposed at two ends of the stator assembly, the end flanges are fixed on the housing, the stator assembly is fixed above the inner steps of the end flanges at the two ends, and the common rotor assembly is located inside the stator assembly and between the end flanges at the two ends.

3. The annular electric thruster of claim 2, wherein the magnetic-hydraulic compound suspension bearing system is located on the end flange, the magnetic-hydraulic compound suspension bearing system comprising: the thrust disc is fixed at the end part of the rotor end plate, a second clearance channel communicated with the first clearance channel is arranged between the thrust disc and the end face flange, and a second water flow channel communicated with the first water flow channel is arranged in the thrust disc and used for forming liquid suspension when water flows pass through the second water flow channel; the dynamic thrust ring is arranged on the inner wall of the thrust disc, and the static thrust ring is arranged on the outer wall of the end face flange at the position corresponding to the dynamic thrust ring and used for generating magnetic repulsion force to form magnetic suspension.

4. The annular electric thruster of claim 3, wherein the rotor end plate is further provided with a radial high pressure water chamber, and the radial high pressure water chamber is respectively communicated with the first clearance passage and the first water flow passage for generating radial high pressure water flow.

5. The annular electric thruster of claim 3, wherein the thrust disc is further provided with a water inlet, the water inlet being in communication with the second water flow channel.

6. The annular electric thruster of claim 5, wherein the water inlet is connected with a high pressure water pump.

7. The annular electric thruster of claim 3, wherein the magnetic-hydraulic compound suspension bearing system further comprises: and the friction reducing block is arranged on the outer wall of the end face flange.

8. The annular electric thruster of claim 3, wherein the dynamic thrust ring and the static thrust ring are permanent magnets or electromagnetic coils wrapped with corrosion-resistant and corrosion-resistant coatings, and have opposite homopolarities to generate magnetic repulsion.

9. Annular electric thruster according to claim 1, characterized in that the vertical height of the housing in the up-down direction is smaller than the outer diameter of the housing at other angles.

10. The annular electric thruster of claim 1, wherein the propeller is an integral propeller or a split propeller.

Technical Field

The invention belongs to the technical field of ship turbine propellers, and particularly relates to a circumferential multi-motor driven annular electric propeller.

Background

With the development of electric propulsion technology, electric propulsion systems are increasingly used on ships. Common electric propulsion systems include change-speed gearboxes, shafting (including shafts, couplings, various bearings and bearing blocks, stern tube seals), propellers, etc.; the electric propulsion system adopts a propulsion mode that after a speed change gear box is driven by a motor to decelerate, a shaft system and a propeller are driven to rotate to generate the forward or backward thrust of the ship. This propulsion method has the following problems: the structure is complex, the number of parts is large, the failure rate is high, the occupied space is large, and the weight is heavy; the propulsion efficiency is low: the motor and the propeller are driven by components such as a gear, a shaft system and the like, the gear is meshed to generate energy loss, and meanwhile, the bearing is usually a sliding bearing, so that the friction force is large and the friction power consumption is large; the transmission links generate intermediate transmission loss, and the propulsion efficiency of the system is reduced; the transmission gear is meshed to generate vibration and cause noise, then, water flow generates turbulent flow after flowing through the shafting and the underwater appendage, the propeller rotates in the turbulent flow to generate excitation and cavitation, and the cavitation bursts to generate noise.

Disclosure of Invention

The invention provides a circumferential multi-motor driven annular electric propeller aiming at the defects of the prior art, which has the advantages of simple principle and structure, high propelling efficiency, low vibration noise, high safety and redundancy and low starting current, can be applied to electric ships, and is particularly suitable for the electric ships with the restriction of shallow draught environments in inland rivers and lakes.

In order to solve at least one of the above technical problems, the technical solution adopted by the present invention is:

a circumferential multi-motor driven annular electric thruster, comprising: a shell, a motor driving unit, a magnetic-liquid composite suspension bearing system and a propeller, wherein,

the motor driving unit includes: the public rotor assembly is arranged on the inner side of the shell, and the stator assemblies are annularly distributed in the shell along the circumferential direction of the shell and form a multi-stator-single-rotor pair with the public rotor assembly;

the magnetic-liquid composite suspension bearing system is connected with the public rotor assembly and used for enabling the public rotor assembly to be in a suspension state; the propellers are connected with the common rotor assembly.

Further, the motor driving unit further comprises end face flanges, the two ends of the stator assembly are respectively provided with the end face flanges, the end face flanges are fixed on the shell, the stator assembly is fixed above the steps on the inner sides of the end face flanges, and the public rotor assembly is located on the inner sides of the stator assembly and between the end face flanges.

Further, compound suspension bearing system of magnetic fluid is located on the terminal surface flange, compound suspension bearing system of magnetic fluid includes: the thrust disc is fixed at the end part of the rotor end plate, a second clearance channel communicated with the first clearance channel is arranged between the thrust disc and the end face flange, and a second water flow channel communicated with the first water flow channel is arranged in the thrust disc and used for forming liquid suspension when water flows pass through the second water flow channel; the dynamic thrust ring is arranged on the inner wall of the thrust disc, and the static thrust ring is arranged on the outer wall of the end face flange at the position corresponding to the dynamic thrust ring and used for generating magnetic repulsion force to form magnetic suspension.

Further, the rotor end plate is also provided with a radial high-pressure water cavity, and the radial high-pressure water cavity is respectively communicated with the first clearance channel and the first water flow channel and is used for generating radial high-pressure water flow.

Furthermore, the thrust disc is also provided with a water inlet which is communicated with the second water flow channel.

Further, the water inlet can be supplied by a high-pressure water pump, and can also be supplied by other high-pressure water sources.

Further, the magnetic-hydraulic compound suspension bearing system further comprises: and the friction reducing block is arranged on the outer wall of the end face flange.

Furthermore, the dynamic thrust ring and the static thrust ring are both permanent magnets or electromagnetic coils wrapped with corrosion-resistant and corrosion-resistant coatings, and the like poles of the permanent magnets or the electromagnetic coils are opposite to each other to generate magnetic repulsion.

Further, the vertical height of the shell in the up-down direction is smaller than the outer diameter of the shell at other angles.

Further, the propeller is an integral propeller or a split propeller.

The beneficial effects of the invention at least comprise:

1) the propulsion efficiency is high: the permanent magnet linear motor rotor adopts the permanent magnet to replace a coil, and compared with the traditional separately excited motor, the current loss is reduced, and the motor efficiency and the power factor are improved; secondly, the motor directly drives the propeller, so that a gear transmission link is eliminated, and the mechanical efficiency loss is reduced; the magnetic-liquid composite suspension bearing system is used, so that the friction loss in the operation process is reduced, and the propulsion efficiency is improved due to the factors;

2) noise vibration is greatly reduced: the noise and vibration caused by the adoption of a gear transmission or contact type sliding bearing pair of the traditional propeller are eliminated; the propeller has uniform incoming flow and small blade vibration; the tip vortex cavitation bubble of the traditional propeller and the noise caused by the tip vortex cavitation bubble are eliminated, and in conclusion, the noise vibration is greatly reduced;

3) the safety and the redundancy of the propeller are improved: a plurality of groups of independent linear motor stator assemblies are arranged in the propeller along the circumferential direction, each motor can be controlled independently, and when the motor is damaged, the other motor still operates and drives the rotor assembly and the propeller, so that the propeller can continue to operate, and potential safety hazards on water caused by the fact that the propeller stops due to damage of the motor and cannot continue to drive the ship to propel are avoided;

4) the starting current is reduced, and the specification requirements on the electrical elements are reduced: each linear motor is driven and controlled by an independent controller, when the propeller is started, only one 1-2 linear motors need to be driven, and all the motors do not need to be started simultaneously, so that the starting current of the motors is reduced, the overcurrent pressure of a motor control circuit element is reduced, the specification and the cost of the circuit element are reduced, and the load and the impact on a marine power grid in the starting process are also reduced;

5) the height of the propeller in the vertical direction is reduced, and the propeller is particularly suitable for the draft limitation of shallow water environments in inland lakes: because a plurality of linear motors of the structural formula of the propeller are independently and separately arranged along the circumferential direction, under the condition that the draught of lakes in rivers is limited, in order to reduce the height limit of the propeller in the vertical direction, motor stator components can not be arranged above and below the circumferential direction of the propeller, so that the vertical height of the propeller is reduced, and the structure avoids the condition that the wheel ring type propeller is lower than the bottom of a ship due to overlarge outer diameter and damages the wheel ring type propeller when touching hard objects.

Drawings

Fig. 1 is a schematic structural view of an annular electric thruster of the present invention.

FIG. 2 is a sectional view taken along line C-C of FIG. 1.

Fig. 3 is a schematic view of the structure of the integrated propeller of the present invention.

Fig. 4 is a schematic structural view of the split propeller of the present invention.

FIG. 5 is a schematic structural diagram of a magnetic-liquid composite suspension bearing system according to the present invention.

Fig. 6 is a partially enlarged view of fig. 5 at a.

The structure comprises a shell 1, a propeller 2, blades 201, a blade tip flange 202, a public rotor assembly 3, a stator assembly 4, an end face flange 5, a magnetic-liquid composite suspension bearing system 6, a rotor end plate 7, a first clearance channel 701, a first water flow channel 702, a radial high-pressure water cavity 703, a thrust disc 8, a second clearance channel 801, a second water flow channel 802, a water inlet 803, a dynamic thrust ring 9, a static thrust ring 10 and a friction reduction block 11.

Detailed Description

In order to make the technical solutions of the present invention better understood by those skilled in the art, the present invention will be further described in detail with reference to specific examples. The following examples are illustrative only and are not to be construed as limiting the invention. The examples, where specific techniques or conditions are not indicated, are to be construed according to the techniques or conditions described in the literature in the art or according to the product specifications.

Fig. 1 is a schematic structural view of an annular electric thruster of the present invention, fig. 2 is a sectional view taken along the direction C-C of fig. 1, and referring to fig. 1 and 2, the annular electric thruster of the present invention, which is driven by a plurality of circumferential motors, mainly includes: the device comprises a shell, a motor driving unit, a magnetic-liquid composite suspension bearing system and a propeller.

Different from the traditional motor, the stator assembly of the motor is not continuous in the circumferential direction, and the stator assemblies are not arranged in the positions above and below the motor in the vertical direction respectively by a section of radian. Because the stator component is not arranged, the shell is arranged outside the rotor, so that the vertical height H of the outer surface of the motor shell in the vertical direction is smaller than the outer diameter D of the motor shell at other angles, the height of the propeller in the vertical direction is reduced, and the propeller is particularly suitable for the draft limitation of shallow water environment in inland lakes.

The invention adopts a plurality of permanent magnet brushless linear motors which are arranged in the circumferential direction, the motors comprise a stator component, a rotor component, a machine shell, an end face flange and the like, the rotor component and the stator component of the motors are completely arranged in water, and a coil, an iron core, a permanent magnet and the like are wrapped by a plurality of layers of insulating and anti-corrosion materials and are isolated from water, so that the permanent magnet brushless linear motors have good insulating property and are corrosion-. The left end and the right end of the rotor are rotor end plates which form a rotor assembly together with the rotor. The stator core is pressed in a motor shell, the motor shell is a propeller shell, the motor shell is connected with an end face flange, and a liquid suspension bearing system is arranged on the end face flange.

More specifically: the two ends of the stator assembly are respectively provided with the end face flanges, the end face flanges are fixed on the shell, the stator assembly is fixed at the two ends and above the inner side steps of the end face flanges, and the public rotor assembly is located on the inner side of the stator assembly and between the end face flanges.

The stator assemblies of the motor are mutually independent and are arranged in the shell at intervals along the circumferential direction, and the radian of each stator assembly is determined according to optimization calculation. The rotor assembly is a public rotor and annular, and the permanent magnet is surface-mounted or embedded in a rotor iron core. Stator-rotor pairs of each motor are formed between the stator assembly coils which are distributed in the circumferential direction and the permanent magnets of the public rotor assembly, each motor is controlled and regulated by an independent controller, each controller controls a three-phase power supply to be connected into the corresponding stator body to generate a rotating magnetic field, and one section of the rotor body corresponding to the length of each stator generates rotation and outputs torque under the action of the rotating magnetic field. The number of the motors is 2 to a plurality, and the number is 2, 3, 4, 5, 6 or more; according to the requirement, 1 of the starting devices can be started, and 2 or more of the starting devices can be started simultaneously, such as 3, 4, 5 and the like.

Of course, it is also possible to combine multiple motors into a single motor by changing the circuit or coil connection manner, i.e. the total number of motors becomes 1.

The diameter of the inner circle of the public rotor assembly is large, the propeller can be accommodated, the propeller is fixed on the inner circle of the public rotor assembly through the blade tip, the propeller is directly driven by the public rotor assembly to rotate, the rotating speed of the motor is the rotating speed of the propeller, intermediate transmission links such as gears are not needed, and thrust is generated after the propeller rotates at a high speed.

The propeller is a metal propeller or a composite propeller. The number of propeller blades is determined according to hydrodynamic performance calculation, and the number of blades can be 2, 3, 4, 5, 6 and the like.

Fig. 3 is a schematic structural view of an integral propeller of the present invention, and as shown in fig. 3, the propeller may be integral, and the blades are connected into a whole by a common blade tip flange and then connected with a common rotor assembly by the blade tip flange.

Fig. 4 is a schematic structural view of the split type propeller of the present invention, as shown in fig. 4, the propeller blades may also be split type, each blade is fixed on the inner circle of the common rotor assembly through a blade tip flange, and is supported and directly driven by the common rotor assembly, and meanwhile, the propeller is made into a split type, which also facilitates the disassembly and replacement.

No matter integral screw propeller or split type screw propeller is no propeller hub type screw propeller, each blade is fixed on a public rotor assembly through a blade tip flange and is directly driven by the public rotor assembly, the rotating speed of a motor is the rotating speed of the screw propeller, and shafting and a propeller hub for supporting and driving are not needed, and intermediate transmission links such as a transmission gear are not needed.

Fig. 5 is a schematic structural view of a magnetic-liquid composite suspension bearing system according to the present invention, and fig. 6 is a partial enlarged view of a portion a of fig. 5. Referring to fig. 5 and 6, the magnetic-hydraulic compound suspension bearing system is located on the end face flange, and the magnetic-hydraulic compound suspension bearing system is composed of a liquid suspension bearing system and a magnetic thrust bearing system.

The liquid suspension bearing system comprises a thrust disc, a friction reducing block, a rotor end plate and a water flow channel arranged inside the rotor end plate and the thrust disc, and is more specific: the rotor end plate is connected with the public rotor assembly, a first clearance channel is arranged between the rotor end plate and the end face flange, a first water flow channel communicated with the first clearance channel is arranged inside the rotor end plate, the thrust disc is fixed at the end part of the rotor end plate, a second clearance channel communicated with the first clearance channel is arranged between the thrust disc and the end face flange, and a second water flow channel communicated with the first water flow channel is arranged inside the thrust disc; the rotor end plate is also provided with a radial high-pressure water cavity which is respectively communicated with the first clearance channel and the first water flow channel and used for generating radial high-pressure water flow; the thrust disc is also provided with a water inlet, the water inlet is communicated with the second water flow channel, and the water inlet is connected with a high-pressure water pump; the friction reducing block is arranged on the outer wall of the end face flange.

The working principle of the liquid suspension bearing system is as follows: when the motor is started, the public rotor assembly starts to rotate, the rotor end plate and the thrust disc which are connected with the public rotor assembly rotate together, water at a water inlet of a second water flow channel in the thrust disc is sucked into the thrust disc, high-pressure water flow is formed under the action of centrifugal force along with the high-speed rotation of the thrust disc and the public rotor assembly, the high-pressure water flow is guided into a radial high-pressure water cavity in the rotor end plate through a first water flow channel, the flow rate of the water flow is reduced, the water pressure is increased, a local high-pressure water area is formed between the radial high-pressure water cavity and the inner circular surface of a matched motor end face flange in a first clearance channel, the water pressure thrust F1 acts on the inner circular surface of the end face flange to form supporting force for supporting the public rotor assembly, the gravity of the public rotor assembly is overcome, the public rotor assembly is supported and, the noise is reduced.

When the motor is started to accelerate and stopped to decelerate, the centrifugal force is weakened, the supporting force generated by high-pressure water pressure is not enough to overcome the gravity of the public rotor assembly and the propeller, the public rotor assembly is in contact with the friction reducing block on the end face flange at the moment and is in a sliding friction state, and the direct friction pair is in a low-resistance friction state due to the low friction coefficient and the low wear rate of the friction reducing block, so that the reliable operation of the propeller in a low-speed state is ensured.

The high-pressure water can be generated by the centrifugal force caused by the high-speed rotation of the public rotor assembly, and can also be directly pumped by an external high-pressure water pump.

Referring to fig. 5 and 6, the magnetic thrust bearing system is composed of a movable thrust ring installed in a thrust disc and a static thrust ring in an end face flange corresponding to the position of the movable thrust ring, so as to form a movable and static thrust bearing pair, wherein the movable thrust ring and the static thrust ring are permanent magnets or electromagnetic coils wrapped with corrosion-resistant and corrosion-resistant coatings, and have opposite homopolarity, so that magnetic repulsion force, namely magnetic thrust F2, is generated. In the running process of the motor, magnetic repulsion force generated between the magnets or between the magnets and the coil separates the movable thrust ring and the static thrust ring, a certain gap is kept, the movable thrust ring and the static thrust ring are in a non-contact suspension state, direct sliding friction between the thrust disc and the flange on the end face of the motor is avoided, and therefore heating and abrasion are greatly reduced.

High-pressure water flow generated by high-speed rotation can also be guided into a second gap channel between the thrust disc and the end face flange, the high-pressure water generates hydraulic thrust F1 towards two sides, the thrust disc and the end face flange are separated, partial axial load of the magnetic thrust bearing is shared, the thrust of a propeller is counteracted together with the magnetic thrust F2 bearing, and the thrust bearing pair is in a suspension state.

The liquid suspension bearing system and the magnetic thrust bearing system jointly form a magnetic-liquid composite suspension bearing pair, support the gravity of the public rotor assembly and the propeller, bear the thrust of the propeller, and transmit the thrust of the propeller to the shell, so that the thrust of the propeller is finally transmitted to the ship body. The magnetic-liquid composite suspension bearing pair is usually positioned on one side of the public rotor assembly instead of two ends of the public rotor assembly, and the structure enables the bearing pair to be arranged on the same part, so that continuous processing is facilitated during processing, the coaxiality between the bearing pairs is ensured, the processing efficiency is improved, and the manufacturing cost is reduced. When the forward and reverse thrust needs to be borne, magnetic-liquid composite suspension bearing systems can be arranged at two ends of the public rotor assembly.

In conclusion, the propeller disclosed by the invention has the advantages of simple principle and structure, high propelling efficiency, low vibration noise, high safety and redundancy and low starting current, can be applied to electric ships, and is particularly suitable for electric ships with limited shallow draft environments in inland rivers and lakes.

In the description of the present invention, it is to be understood that the terms "first", "second" and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

Although embodiments of the present invention have been shown and described, it is understood that the embodiments are illustrative and not restrictive, that various changes, modifications, substitutions and alterations may be made herein without departing from the spirit and scope of the invention as defined by the appended claims.