CN107070161B - Double-mover double-winding plate type linear generator based on magnetic field modulation principle - Google Patents

Abstract

The double-mover double-winding flat-plate linear generator based on the principle of magnetic field modulation belongs to the field of linear generators for wave power generation. The invention includes a casing, a double-winding stator, a permanent magnet mover, a modulating mover, an output end of the permanent magnet mover and an output end of the modulating mover; the double-winding stator is symmetrically fixed in the upper and lower parts of the casing with the axis plane as the symmetrical plane On the surface, a permanent magnet mover is arranged inside the double winding stator, and a modulation mover is arranged between the permanent magnet mover and the double winding stator; the right end of the permanent magnet mover protrudes from the right end cover of the casing as a permanent magnet mover. Sub output end; the modulation mover is a symmetrical structure with the axis plane as the symmetry plane; the left side of the modulation mover protrudes from the shell as the modulation mover output end; the axis symmetry plane of the modulation mover output end and the permanent magnet mover output end coincide.

Description

Double-mover double-winding flat-plate linear generator based on the principle of magnetic field modulation

technical field

The invention belongs to the field of linear generators for wave power generation.

Background technique

Ocean wave energy is a clean power generation energy, which can meet the needs of ocean observation instruments, military and civilian test buoys, Dokdo, and operating platforms through wave energy generation. At present, the traditional wave energy power generation method usually uses a mechanical device to convert the vertical linear motion of the wave into a rotary motion, and drives the rotary generator to generate electricity. In contrast, the direct-drive power generation method uses the energy recovery device and the linear motor to directly combine the power generation, which saves the complex mechanical transmission link in the middle, improves the power generation efficiency of the system, and improves the integration and stability of the power generation system. improved. Therefore, direct-drive wave power generation has broad application prospects. However, in the current direct-drive power generation system, due to the large thrust, low speed and inconstancy of the linear motion converted by the energy recovery device, the parameters such as the amplitude and frequency of the power generation voltage of the linear motor change greatly, resulting in poor power generation quality of the system. There may even be problems such as system instability.

SUMMARY OF THE INVENTION

The purpose of the invention is to solve the problem of poor power generation quality of the existing direct-drive wave power generation system, and to provide a double-mover double-winding flat-plate linear generator based on the principle of magnetic field modulation.

The double-mover double-winding flat-plate linear generator based on the magnetic field modulation principle of the present invention comprises a casing, a double-winding stator, a permanent magnet mover, a modulating mover, an output end of the permanent magnet mover and an output end of the modulating mover;

The double-winding stator is symmetrically fixed on the upper and lower inner surfaces of the casing with the axis plane as the symmetry plane, a permanent-magnet mover is arranged inside the double-winding stator, and a modulation mover is arranged between the permanent-magnet mover and the double-winding stator;

The left end of the permanent magnet mover is slidably connected to the modulation mover through the second guide rail, and the right end of the permanent magnet mover protrudes from the right end cover of the casing as the output end of the permanent magnet mover, and is also connected to the modulation mover through the third guide rail. child sliding connection;

The modulating mover is a symmetrical structure with the axis plane as the symmetry plane; both ends of the modulating mover protrude from the end covers on both sides of the casing, and the right protruding part passes through the third guide rail and the fourth guide rail and the permanent magnet mover. The left end cover is slidably connected to the right end cover of the casing; the left extension is used as the output end of the modulation mover, and the output end of the modulation mover is connected to the left end cover and the permanent end cover of the casing through the first guide rail and the second guide rail respectively. Magnetic mover sliding connection;

There is a radial air gap L1 between the modulation mover plane and the double-winding stator plane; there is a radial air gap L2 between the modulation mover plane and the permanent magnet mover plane; the axis of the modulation mover output end and the permanent magnet mover output end The planes of symmetry coincide.

Preferably, the double-winding stator is composed of a stator core, a first stator winding and a second stator winding; the first stator winding is symmetrically distributed with the axis plane as the symmetry plane, and both sides of the symmetry are m ₁ -phase stator windings, when When the m ₁ phase AC current is passed through the first stator winding, a ps ₁ pole pair armature magnetic field will be formed along the axis direction, and m ₁ and ps ₁ are positive integers; the second stator winding faces the axis plane symmetrically. The distribution is symmetrical, and both sides of the symmetry are m ₂ -phase stator windings. When the second stator winding has m ₂ -phase alternating current, it will form a ps ₂ pole pair armature magnetic field that moves along the axis direction, m ₂ , ps ₂ is a positive integer.

Preferably, the permanent magnet mover is a symmetrical structure with the axis plane as the symmetry plane, and the number of pole pairs on both sides of symmetry is p _PM , and p _PM is a positive integer _; It consists of 2p PM permanent magnet units; 2p _PM permanent magnet units are evenly distributed along the axis direction on each side, 2p _PM permanent magnet units are fixed on the upper and lower surfaces of the permanent magnet mover core, and the charging of the adjacent two permanent magnet units The magnetic directions are opposite; the magnetization direction of the permanent magnet unit is parallel magnetization.

Preferably, the modulating mover is a symmetrical structure with the axis plane as the symmetry plane, and is composed of _{2pm magnetic permeable blocks, 2pm non-magnetic permeable blocks and a mover bracket, and p m is a} positive integer; The mover bracket is staggered along the axis direction to arrange p _m magnetic permeable blocks and p _m non-magnetic permeable blocks.

The conditions p _s1 =|kp _PM +jp _m | and p _s2 =kp _PM are satisfied at the same time, where k is a positive integer and j is an integer.

Preferably, the magnetic conductive block is selected from soft magnetic composite material, silicon steel sheet, solid iron or soft ferrite.

Advantages of the present invention: the double-mover double-winding flat-plate linear generator based on the magnetic field modulation principle has two independent movers, and the thrust and speed of the two movers are completely independent; at the same time, the motor is a symmetrical structure, There is no unilateral magnetic pull in the motor. Therefore, in the actual wave power generation system, no matter how one mover moves with the waves, through the effective control of the other mover, the voltage amplitude and frequency emitted by the generator can be kept constant, thereby improving the power generation quality of the power generation system. and system stability.

Description of drawings

Fig. 1 is the structural representation of described double-mover double-winding flat-plate linear generator based on the principle of magnetic field modulation;

Fig. 2 is the enlarged view of A place of Fig. 1;

3 is a schematic diagram of the winding arrangement of the first stator winding;

FIG. 4 is a schematic diagram of the winding arrangement of the second stator winding.

Detailed ways

The present invention will be described in detail below with reference to FIGS. 1 to 4 . FIG. 1 is a schematic structural diagram of an embodiment of a double-mover double-winding flat-plate linear generator based on the principle of magnetic field modulation.

The double-mover double-winding flat-plate linear generator based on the magnetic field modulation principle of the present invention includes a casing 4, a double-winding stator 5, a permanent magnet mover 7, a modulation mover 6, a permanent magnet mover output end 10 and a modulation drive Sub output 1;

The double-winding stator 5 is symmetrically fixed on the upper and lower inner surfaces of the casing 4 with the axis plane as the symmetry plane. A permanent magnet mover 7 is arranged inside the double-winding stator 5 , and a permanent magnet mover 7 is arranged between the permanent magnet mover 7 and the double-winding stator 5 . Modulator 6

The left end of the permanent magnet mover 7 is slidably connected to the modulation mover 6 through the second guide rail 3, and the right end of the permanent magnet mover 7 protrudes from the right end cover of the casing 4 as the permanent magnet mover output end 10, and passes through the first The three guide rails 8 are also slidably connected with the modulation mover 6;

The modulation mover 6 is a symmetrical structure with the axis plane as the symmetry plane; the two ends of the modulation mover 6 respectively protrude from the end covers on both sides of the casing, and the right extension part passes through the third guide rail 8 and the fourth guide rail 9 It is slidably connected with the permanent magnet mover 7 and the right end cover of the casing 4; wherein the left protruding part is used as the modulation mover output end 1, and the modulation mover output end 1 passes through the first guide rail 2 and the second guide rail 3 are respectively slidingly connected with the left end cover of the casing 4 and the permanent magnet mover 7;

There is a radial air gap L1 between the plane of the modulation mover 6 and the plane of the double-winding stator 5; there is a radial air gap L2 between the plane of the modulation mover 6 and the plane of the permanent magnet mover 7; the output end 1 of the modulation mover and the permanent magnet The axes of symmetry planes of the mover output end 10 are coincident.

The double-winding stator 5 is composed of a stator iron core 5-3, a first stator winding 5-1 and a second stator winding 5-2; the first stator winding 5-1 is symmetrically distributed with the axis plane as the symmetrical plane, and the symmetrical two Both sides are m ₁ -phase stator windings. When the first stator winding 5-1 has m ₁ -phase alternating current, it will form _{a ps1} pole-pair armature magnetic field that moves along the axis direction, and m1 and _ps1 are positive. Integer; the second stator winding 5-2 is symmetrically distributed with the axis plane as the symmetry plane, and both sides of the symmetry are m ₂ -phase stator windings. When the second stator winding 5-2 is connected with m ₂ -phase alternating current, it will form P _s2 pole pair number armature magnetic field moving along the axis direction, m ₂ , p _s2 are positive integers.

The permanent magnet mover 7 is a symmetrical structure with the axis plane as the symmetry plane, and the number of pole pairs on both sides of the symmetry is p _PM , and p _PM is a positive integer; the permanent magnet mover 7 is composed of the permanent magnet mover iron core 7-2 and 4p _PM permanent magnet units 7-1 are formed; 2p _PM permanent magnet units 7-1 are evenly distributed and arranged along the axis direction on each side, and 2p _PM permanent magnet units 7-1 are fixed on the permanent magnet mover core 7-2 On the upper and lower surfaces of the two adjacent permanent magnet units 7-1, the magnetization directions are opposite; the magnetization directions of the permanent magnet units 7-1 are parallel magnetization.

The modulation mover 6 is a symmetrical structure with the axis plane as the symmetrical plane, and is composed of _2pm magnetic conductive blocks 6-1, _2pm non-magnetic conductive blocks 6-2 and a mover bracket _6-3 , and pm is positive Integer; pm magnetic _permeable blocks 6-1 and pm non-magnetic _permeable blocks 6-2 are staggered along the axis direction of the mover bracket 6-3 on each side.

The conditions p _s1 =|kp _PM +jp _m | and p _s2 =kp _PM are satisfied at the same time, where k is a positive integer and j is an integer.

The magnetic conductive block 6-1 is made of soft magnetic composite material, silicon steel sheet, solid iron or soft ferrite.

In order to illustrate the working principle of the present invention, the following description is made with reference to FIGS. 1 to 4 .

Assuming that the number of pole pairs on both sides of the permanent magnet mover is p _PM , the speed is V _PM , and the initial phase angle is θ _PM , then the permanent magnet magnetomotive force F _PM (θ,t) formed by the permanent magnet mover moving along the axis direction ) can be expressed as

In the formula, F _k ——the magnitude of each harmonic magnetomotive force;

k——harmonic number of permanent magnet magnetomotive force;

θ——Mechanical angle;

t - time.

Assuming that the number of permeable blocks on both sides of the modulating mover is p _m , the velocity is V _m , and the initial phase angle is θ _m , the space ratio permeance λ(θ, t) that changes with time under the action of the modulating mover can be expressed as for

where λ ₀ , λ _i ——the permeance amplitude of each harmonic ratio;

i——The number of harmonic permeance ratio.

The permanent magnet magnetic field moving along the axis direction generated by the magnetomotive force of the permanent magnet under the action of the modulating mover can be expressed as

where B _k is the amplitude of the natural harmonic magnetic field, and B _k = F _k λ ₀ ;

B _k,i — the modulated harmonic magnetic field amplitude, and B _k,i =F _k λ _i .

It can be seen from formula (3) that two types of magnetic fields will be generated under the joint action of the permanent magnet mover and the modulation mover. The first type is the natural harmonic magnetic field. The characteristic of this type of magnetic field is that its magnetic field pole pairs and velocity are the same as those of the magnetomotive force of the permanent magnet mover, and the amplitude of this type of magnetic field is B _k . The second type is the modulated harmonic magnetic field. The characteristic of this type of magnetic field is that the number of pole pairs of the magnetic field is related to the number of pole pairs of the permanent magnet mover and the number of permeable blocks in the modulation mover, and its magnetic field speed is also related to the permanent magnet mover. is related to the velocity of both the modulating mover, and the magnitude of this type of magnetic field is B _k,i , as follows:

p _k,j =|kp _PM +jp _m | (4)

j=0,±1,±2,... (6)

where p _k,j and V _k,j are the number of pole pairs and synchronizing velocity of the modulated harmonic magnetic field.

According to the principle of electromechanical energy conversion, only when the pole pairs and speeds of the two magnetic fields are the same, a constant thrust can be generated, thereby realizing electromechanical energy conversion. Therefore, the second stator winding 5-2 is designed through the winding arrangement to generate the armature magnetic field with the same number of pole pairs and speed as the modulated harmonic magnetic field. Then, the second stator winding 5-2, the modulation mover and the permanent magnet mover constitute a magnetic field modulation type double mover linear motor. In this case, the electromagnetic thrust acting on the modulating mover is equal to the sum of the electromagnetic thrusts acting on the stator and the permanent magnet mover, and their electromagnetic thrusts are in opposite directions. At the same time, the thrust relationship between the modulating mover and the permanent magnet mover and between the modulating mover and the second stator winding 5-2 is always proportional. In addition, the speed of the armature magnetic field generated by the second stator winding 5-2 is equal to the speed of the modulated harmonic magnetic field, therefore, the speed can be adjusted with reference to formula (5). Therefore, due to the interaction between the second stator winding 5-2, the modulation mover and the permanent magnet mover, the modulation mover and the permanent magnet mover can only achieve speed decoupling, but the thrust between them is still coupled. In practical applications, if only one set of windings (the second stator winding 5-2) is used, the voltage emitted by the windings will be extremely unstable due to the uncertainty of the wave motion.

Further, the second stator winding 5-2 can be designed to generate an armature magnetic field with the same pole pair number and speed as the natural harmonic magnetic field. Then, the second stator winding 5-2 and the permanent magnet mover constitute a permanent magnet synchronous linear motor. At this time, the second stator winding 5-2 only acts with the permanent magnet mover to generate thrust, and does not generate thrust with the modulation mover. In addition, since the number of pole pairs of the armature magnetic field generated by the second stator winding 5-2 and the second stator winding 5-2 are different, no thrust is generated between them, in other words, there is no influence between them. Therefore, through the interaction between the second stator winding 5-2 and the permanent magnet mover, the thrust decoupling of the modulation mover and the permanent magnet mover can be realized.

It can be seen from the above analysis that the electromagnetic thrust on the modulating mover is only related to the second stator winding 5-2, and the speed of the modulating mover is related to the armature magnetic field of the second stator winding 5-2 and the speed of the permanent magnet mover; The electromagnetic thrust on the magnet mover is not only related to the second stator winding 5-2, but also affected by the second stator winding 5-2, and the speed of the permanent magnet mover is only related to the armature magnetic field speed of the second stator winding 5-2. same. Therefore, for the double-mover double-winding flat-plate linear generator based on the principle of magnetic field modulation, the thrust and speed of the modulating mover are completely independent of the thrust and speed of the permanent magnet mover. In addition, the motor has a symmetrical structure, and there is no unilateral magnetic pull in the motor.

In practical application, the modulation mover is connected with the wave transmission device, so the movement of the modulation mover has great randomness. At this time, the thrust and speed of the permanent magnet rotor are effectively controlled by the second stator winding 5-2, so that the speed of the armature magnetic field of the second stator winding 5-2 is always kept constant, thereby making the double mover based on the magnetic field modulation principle The voltage amplitude and frequency of the double-winding cylindrical linear generator are always kept constant, which significantly improves the power generation quality of the entire power generation system.

Specifically, the number of pole pairs of the permanent magnet mover in FIG. 1 is 6, and the number of magnetic conductive blocks in the modulation mover is 10. It can be known from equation (4) that a series of modulated harmonic magnetic fields will be generated in the air gap. Among these modulated harmonic magnetic fields, the amplitude of the corresponding modulated harmonic magnetic field is usually the largest when k=1, j=-1, that is to say, the amplitude of the four pairs of polar magnetic fields in the modulated harmonic magnetic field is the largest. Therefore, the second stator winding 5-2 can generate four pairs of pole armature magnetic fields through the winding arrangement design, as shown in FIG. 3 (the first stator winding 5-1 is symmetrically distributed with the axis plane as the The winding arrangement of the side is the same, and the figure shows the winding arrangement of any side). And by controlling the second stator winding 5-2 to generate the armature magnetic field at the same speed as the 4-pole modulated harmonic magnetic field, the second stator winding 5-2, the modulation mover and the permanent magnet mover can realize electromechanical energy conversion. .

At this time, it can also be known from equation (3) that a series of natural harmonic magnetic fields will be generated in the air gap. Among these natural harmonic magnetic fields, when k=1, the corresponding natural harmonic magnetic field has the largest amplitude, that is to say, the permanent magnet magnetic field has the largest amplitude. The sub-generating 6 pairs of poles have the largest amplitude of the natural harmonic magnetic field. Therefore, the second stator winding 5-2 can generate 6 pairs of pole armature magnetic fields through the winding arrangement design, as shown in FIG. The winding arrangement is the same, the figure shows the winding arrangement on either side). And by controlling the second stator winding 5-2 to generate the armature magnetic field at the same speed as the 6 pairs of polar natural harmonic magnetic fields, the second stator winding 5-2 and the permanent magnet mover can realize electromechanical energy conversion.

In addition, since the number of pole pairs of the armature magnetic field generated by the second stator winding 5-2 and the second stator winding 5-2 is different (one is a 4-pole armature magnetic field, and the other is a 6-pole armature magnetic field), according to the electromechanical The principle of energy conversion, there is no thrust between them. In other words, they do not affect each other.

The final effect is equivalent to that the second stator winding 5-2, the modulation mover and the permanent magnet mover are a double mover motor; while the second stator winding 5-2 and the permanent magnet mover are equivalent to the traditional permanent magnet synchronous straight line motor. In this way, the speed decoupling of the modulating mover and the permanent magnet mover can be achieved through the control of the second stator winding 5-2, but the thrusts of the two are coupled (not independent); further through the control of the second stator winding 5-2 The control can realize the thrust decoupling between the modulating mover and the permanent magnet mover. Therefore, in practical applications, the effective control of the permanent magnet mover is achieved through the second stator winding 5-2, and even under the random variable speed movement of the modulating mover, the voltage amplitude, The frequency is constant, so that the power generation quality of the entire power generation system is improved, and the stability of the system operation is also improved. In addition, the motor has a symmetrical structure, and there is no unilateral magnetic pull in the motor.

Claims (2)

1. A double-mover double-winding flat-plate linear generator based on the principle of magnetic field modulation, characterized in that it comprises a casing (4), a double-winding stator (5), a permanent magnet mover (7), and a modulation mover (6) , the permanent magnet mover output end (10) and the modulation mover output end (1); The double-winding stator (5) is symmetrically fixed on the upper and lower inner surfaces of the casing (4) with the axis plane as the symmetry plane, and a permanent-magnet mover (7) is arranged inside the double-winding stator (5). ) and the double-winding stator (5) are provided with a modulation mover (6); The left end of the permanent magnet mover (7) is slidably connected to the modulation mover (6) through the second guide rail (3), and the right end of the permanent magnet mover (7) protrudes from the right end cover of the casing (4) as a permanent magnet. The magnetic mover output end (10) is also slidably connected with the modulation mover (6) through the third guide rail (8); The modulation mover (6) is a symmetrical structure with the axis plane as the symmetry plane; the two ends of the modulation mover (6) respectively protrude from the end covers on both sides of the casing (4), wherein the right protruding part passes through the third part. The guide rail (8) and the fourth guide rail (9) are slidably connected with the permanent magnet mover (7) and the right end cover of the casing (4); the left protruding part is used as the output end (1) of the modulating mover, so the The modulation mover output end (1) is slidably connected to the left end cover of the casing (4) and the permanent magnet mover (7) through the first guide rail (2) and the second guide rail (3), respectively; A radial air gap L1 exists between the plane of the modulation mover (6) and the plane of the double-winding stator (5); a radial air gap L2 exists between the plane of the modulation mover (6) and the plane of the permanent magnet mover (7); The axis symmetry planes of the mover output end (1) and the permanent magnet mover output end (10) coincide; The double-winding stator (5) is composed of a stator core (5-3), a first stator winding (5-1) and a second stator winding (5-2); the first stator winding (5-1) is arranged in the axis plane It is symmetrically distributed on the symmetrical plane, and both sides of the symmetry are m ₁ -phase stator windings. When the first stator winding (5-1) is supplied with m ₁ -phase alternating current, a p _s1 pole pair that moves along the axis will be formed. Number of armature magnetic fields, m ₁ , p _s1 are positive integers; the second stator winding (5-2) is symmetrically distributed with the axis plane as the symmetry plane, and both sides of the symmetry are m ₂ -phase stator windings, when the second stator winding (5-2) When m ₂ -phase alternating current is passed through, a ps ₂ pole-pair armature magnetic field will be formed that moves along the axis direction, and m ₂ and ps ₂ are positive integers; The permanent magnet mover (7) is a symmetrical structure with the axis plane as the symmetry plane, and the number of pole pairs on both sides of symmetry is p _PM , and p _PM is a positive integer; the permanent magnet mover (7) is composed of a permanent magnet mover iron core. (7-2) and 4p _PM permanent magnet units (7-1); on each side 2p _PM permanent magnet units (7-1) are evenly distributed along the axis direction, 2p _PM permanent magnet units (7- 1) Fixed on the upper and lower surfaces of the permanent magnet mover core (7-2), the magnetization directions of the two adjacent permanent magnet units (7-1) are opposite; the magnetization directions of the permanent magnet units (7-1) are Parallel magnetization; The modulation mover (6) is a symmetrical structure with the axis plane as the symmetry plane, and consists of _2pm magnetic conductive blocks (6-1), _2pm non-magnetic conductive blocks (6-2) and a mover bracket (6- 3) Composition, p _m is a positive integer; p _m magnetic conductive blocks (6-1) and p _m non-magnetic conductive blocks (6- 2); The conditions p _s1 =|kp _PM +jp _m | and p _s2 =kp _PM are satisfied at the same time, where k is a positive integer and j is an integer. 2. The double-mover double-winding flat-type linear generator based on the principle of magnetic field modulation according to claim 1, is characterized in that, the magnetic conductive block (6-1) selects soft magnetic composite material, silicon steel sheet, solid iron or soft magnet for use oxygen body.

Images