CN115622305A - A generator with constant speed and frequency regulation function - Google Patents

Abstract

The invention discloses a generator with constant speed and frequency modulation function, comprising a stator and a rotor, the stator comprises a stator core, a first winding and a second winding, both the first winding and the second winding are wound on the stator core, the second winding Compared with the first winding, it is closer to the rotor in the radial direction of the stator, and the rotor includes a rotating shaft and a first rotor magnetic pole group and a second rotor magnetic pole group arranged in the circumferential direction of the rotating shaft. Compared with the first rotor magnetic pole group, the second rotor magnetic pole group Closer to the stator in the radial direction of the rotor, the polarities of the magnets constituting the first rotor pole group and the second rotor pole group alternately change in their respective circumferential directions, and the pole numbers of the first rotor pole group and the second rotor pole group are different, The number of poles of the first rotor magnetic pole set is the same as that of the first winding, and the number of poles of the second rotor magnetic pole set is the same as that of the second winding. The invention does not need frequency conversion of power electronic devices, and can realize frequency conversion output at a constant rotating speed.

Description

A generator with constant speed and frequency regulation function

technical field

The invention relates to a generator, in particular to a generator with the function of constant speed and frequency regulation.

Background technique

With the rapid development of transportation electrification, the load power and speed levels of electric drive vehicle auxiliary systems tend to be diverse. Permanent magnet motors have the advantages of high power density, high efficiency and good dynamic characteristics, and have been widely used in various transportation electric drive systems. The rotor magnetic field of the brushless permanent magnet motor is established by high-performance permanent magnets, and the number of poles and magnetic properties are constant after magnetization is completed, so it has excellent output characteristics and torque retention. However, the constant magnet performance and number of poles lead to the fact that the motor speed cannot be adjusted autonomously like an asynchronous motor, and power electronic devices must be used to realize frequency regulation and speed regulation. Similarly, in the generator system, when the speed of the prime mover is constant, the frequency of the output AC electromagnetic quantity is constant, and it can only be used by frequency modulation, rectification, and inversion of power electronic devices for various loads with different frequencies.

When the frequency modulation of power electronic devices is used, the complexity and volume of the system will be greatly increased, the power density and efficiency will be reduced, the difficulty of processing and manufacturing will increase, and the cost will increase significantly. On the other hand, all kinds of power electronic devices have low temperature resistance, poor overload capacity, weak anti-electromagnetic interference ability, low redundancy of control algorithms, and low reliability in complex working conditions and special application environments. At the same time, for applications that do not require continuous frequency regulation, the advantages of power electronic speed regulation cannot be fully utilized, and there is no comparative advantage in performance. In addition, power electronic devices will introduce new interference in the process of rectification, voltage stabilization and inverter, which is not conducive to the stable operation of driving loads and other equipment in the same installation environment.

Contents of the invention

In order to overcome the deficiencies of the above-mentioned prior art, the present invention provides a generator with constant-speed frequency modulation function, which solves the frequency conversion problem when the prime mover rotates at a constant speed, and realizes two-stage frequency conversion output.

The technical solution of the present invention is as follows: a generator with constant speed and frequency modulation function, including a stator and a rotor, the stator includes a stator core, a first winding and a second winding, and both the first winding and the second winding are wound Manufactured on the stator core, the second winding is closer to the rotor in the radial direction of the stator than the first winding, and the rotor includes a rotating shaft and a first rotor pole group arranged in the circumferential direction of the rotating shaft and a second rotor pole group, the second rotor pole group is closer to the stator in the radial direction of the rotor than the first rotor pole group, forming the first rotor pole group and the second rotor pole group The polarities of the magnets of the rotor pole group alternately change in respective circumferential directions, the number of poles of the first rotor pole group and the second rotor pole group are different, and the number of poles of the first rotor pole group is different from that of the second rotor pole group. The number of poles of the first winding is the same, and the number of poles of the second rotor magnetic pole group is the same as that of the second winding.

Further, the stator is arranged on the periphery of the rotor, and the second rotor pole set is an integral magnetic ring. In this way, it is no longer necessary to arrange a non-magnetically conductive protective cover outside the second rotor magnetic pole group.

Another technical solution of the present invention is as follows: a generator with a constant-speed and frequency-regulating function includes a stator, a first rotor and a second rotor, the stator is arranged between the first rotor and the second rotor, The stator includes a stator core, a first winding and a second winding, both the first winding and the second winding are wound on the stator core, the first winding is radially close to the first rotor, The second winding is radially close to the second rotor, the first rotor and the second rotor have a common rotating shaft, and the first rotor is provided with a first rotor circumferentially arranged around the outer side of the stator magnetic pole set, the second rotor is provided with a second rotor magnetic pole set circumferentially arranged around the inner side of the stator, the number of poles of the first rotor magnetic pole set is different from that of the second rotor magnetic pole set, and the first rotor The number of poles of the magnetic pole group is the same as that of the first winding, and the number of poles of the second rotor magnetic pole group is the same as that of the second winding.

Further, the first rotor pole set and/or the second rotor pole set are DC field windings.

Further, the magnetization directions of the first rotor pole group and the second rotor pole group are the same, and both are magnetized in a radial or parallel manner.

Further, the magnets of the first rotor pole group and the second rotor pole group are evenly spaced in the circumferential direction.

The advantage of the technical solution provided by the present invention is:

The invention does not need to use power electronic frequency conversion technology to realize the secondary frequency conversion output. When the prime mover rotates at a constant speed, alternating currents of different frequencies can be generated by simply switching windings to drive loads with different frequency requirements. Second, the proposed generator system has a simple structure, high efficiency, and high reliability. At the same time, without using expensive power electronic devices, the cost of materials and installation and application of the generator system is reduced, and the difficulty of control is reduced. Furthermore, after eliminating the frequency conversion system, the volume of the generator is greatly reduced, the power density is high, the requirements for the installation environment are reduced, the interference to the outside world is small, and the application range is wider.

Description of drawings

Fig. 1 is a schematic structural diagram of a generator with constant-speed and frequency-regulating functions in Embodiment 1.

FIG. 2 is a structural schematic diagram of the stator core and the first winding of the generator with constant-speed and frequency-regulating functions in Embodiment 1. FIG.

FIG. 3 is a structural schematic diagram of the stator core and the second winding of the generator with constant-speed and frequency-regulating functions in Embodiment 1. FIG.

FIG. 4 is a schematic diagram of the rotor structure of the generator with constant-speed and frequency-regulating function in Embodiment 1. FIG.

Fig. 5 is a structural schematic diagram of a generator with constant speed and frequency regulation function in Embodiment 2.

Fig. 6 is a schematic structural diagram of the stator of the generator with constant-speed and frequency-regulating functions in Embodiment 2.

Fig. 7 is a schematic diagram of the rotor structure of the generator with constant-speed and frequency-regulating function in Embodiment 2.

Fig. 8 is a schematic structural diagram of a generator with constant-speed and frequency-regulating functions in Embodiment 3.

Fig. 9 is a schematic structural diagram of the stator of the generator with constant-speed and frequency-regulating functions in Embodiment 3.

Fig. 10 is a schematic diagram of the rotor structure of the generator with constant-speed and frequency-regulating function in Embodiment 3.

detailed description

The present invention will be further described below in conjunction with the examples, but not as a limitation of the present invention.

Embodiment 1, please refer to Fig. 1 to Fig. 4, this embodiment relates to a generator with constant speed and frequency modulation function, its rated power is 3000W, and its rated speed is 5400r/min. The generator with constant speed and frequency modulation function includes a stator 100 and a rotor 101 , the stator 100 is arranged on the periphery of the rotor 101 , and has an outer stator 100 and an inner rotor 101 structure.

The stator 100 includes a stator core 1001 made of laminated 0.35 mm non-oriented silicon steel sheets, and two sets of three-phase windings wound on the stator core 1001 , namely the first winding 1002 and the second winding 1003 . The stator core 1001 has 18 uniformly distributed slots 1001a along the circumference, and the 18 stator teeth 1001b formed by the slots 1001a are respectively wound with a first winding 1002 and a second winding 1003 according to inner and outer layers. The first winding 1002 is wound as an outer ring, which includes 9 coils, each coil of the first winding 1002 spans two stator teeth 1001b, the pitch of the coils of the first winding 1002 is 2, and the number of turns is 12, forming A 6-pole 9-slot winding, as shown in Figure 2. The second winding 1003 is wound as an inner ring, which is closer to the rotor 101 than the first winding 1002, and also includes 9 coils. The coil of the second winding 1003 spans two stator teeth 1001b, the pitch is 2, and the number of turns is 15. , forming an 8-pole 9-slot winding, as shown in Figure 3.

As shown in FIG. 4 , the rotor 101 of the generator is located inside the stator 100 , including a shaft 1011 and a first rotor pole set 1012 and a second rotor pole set 1013 that surround the shaft 1011 and are arranged circumferentially on the shaft 1011 . The rotating shaft 1011 is processed and manufactured by 45# magnetic steel, and is connected to the output shaft of the diesel engine. The first rotor pole group 1012 includes 6 permanent magnets, which are evenly distributed along the circumference and attached to the outside of the rotating shaft 1011. Radial magnetization is adopted, and the polarities of the magnets are staggered to form 6 magnetic poles. The first rotor pole group The number of poles of 1012 is the same as the number of poles of the first winding 1002 .

The second rotor pole set 1013 includes 8 permanent magnets, which are uniformly distributed along the circumference and attached to the outside of the first rotor pole set 1012. Radial magnetization is adopted, and the polarities of the magnets are staggered to form 8 poles. The number of poles of the second rotor pole set 1013 is the same as that of the second winding 1003 . In this embodiment, the outer side of the second rotor magnetic pole set 1013 is covered with a non-magnetic sheath 1014, and the sheath 1014 is made of Inconel 718 alloy steel.

As a preferred embodiment, the magnetic pole group of the second rotor 101 can be set as a complete magnetic ring, so that the radial position of the magnetic pole group of the first rotor 101 can be limited by the magnetic pole group of the second rotor 101 so that no additional settings are required. Magnetic sheath.

As another preferred implementation manner, the permanent magnets used in the first rotor pole set 1012 and the second rotor pole set 1013 can all be replaced by DC field windings. When the DC field winding of the first rotor pole set 1012 is energized, the DC field winding of the second rotor pole set 1013 is set to an open circuit state. When the DC field winding of the second rotor pole set 1013 is energized, the DC field winding of the first rotor pole set 1012 is set to an open circuit state. By setting the on-off state of two sets of DC excitation windings, the current of the rotor DC excitation windings changes synchronously with the load torque of the generator, and the stability of the generator speed and frequency is enhanced. Alternatively, the permanent magnet used in any one of the first rotor pole set 1012 and the second rotor pole set 1013 is replaced by a DC field winding.

During the operation of the generator with constant speed and frequency modulation function in this embodiment, the output shaft of the diesel engine is connected to the rotating shaft of the rotor 101, the rotor 101 rotates, and the first rotor magnetic pole set 1012 induces a three-phase frequency of 270 Hz in the first winding 1002. AC voltage, the second rotor pole group 1013 induces a three-phase AC voltage with a frequency of 360 Hz in the second winding 1003 . A switch is used to switch between the first winding 1002 and the second winding 1003, that is, to realize the two-stage frequency modulation function of constant speed, and to drive loads with different frequency requirements.

Embodiment 2, please refer to Fig. 5 to Fig. 7, another structure of the generator with constant speed and frequency modulation function includes a stator 200 and a rotor 201, the stator 200 is arranged inside the rotor 201, which is an outer rotor inner stator structure.

The stator 200 includes a stator core 2001 and two sets of three-phase windings wound on the stator core 2001 , that is, a first winding 2002 and a second winding 2003 . The outer peripheral surface of the stator core 2001 is provided with evenly distributed slots 2001a along the circumferential direction, and the first winding 2002 and the second winding 2003 are wound on the stator teeth 2001b formed between the slots 2001a. The first winding 2002 near the center of the stator core 2001 is an inner winding, and the second winding 2003 is an outer winding.

The rotor 201 of the generator is cylindrical, surrounds the stator 200 and includes a sheath 2011 , and a first rotor pole set 2012 and a second rotor pole set 2013 are circumferentially arranged inside the sheath 2011 . The rotating shaft (not shown in the figure) of the rotor 201 is arranged coaxially with the sheath 2011 and is fixed with the sheath 2011, which is driven by a diesel engine. The first rotor pole set 2012 includes 8 radially magnetized permanent magnets, and the 8 permanent magnets are attached to the inner wall of the sheath 2011 and distributed evenly along the circumference. The number of poles of the first rotor pole set 2012 is the same as that of the first winding 2002 . The second rotor pole set 2013 includes 6 radially magnetized permanent magnets, and the 6 permanent magnets are attached to the inner wall of the first rotor pole set 2012 and distributed evenly along the circumference. the same number of poles. Therefore, when the rotor 201 is rotated by the diesel engine, at the same rotational speed, AC voltages of different frequencies can be induced in the first winding 2002 and the second winding 2003, realizing the constant rotational speed two-stage frequency modulation function, and driving loads with different frequency requirements.

Embodiment 3, please refer to FIG. 8 to FIG. 10 , another structure of the generator with constant speed and frequency modulation function includes a stator 300 and two rotors, the two rotors are the first rotor 301 and the second rotor 302 , the stator 300 is disposed between the first rotor 301 and the second rotor 302 .

The stator 300 includes a stator core 3001 and two sets of three-phase windings wound on the stator core 3001 , that is, a first winding 3002 and a second winding 3003 . The outer peripheral surface and the inner peripheral surface of the stator core 3001 are provided with outer slots 3001a and inner slots 3001b evenly distributed along the circumferential direction, and the first winding 3002 is wound on the outer stator teeth 3001c formed between the outer slots 3001a, between the inner slots 3001b The second winding 3003 is wound around the formed inner stator teeth 3001d. The first rotor 301 and the second rotor 302 have the same rotating shaft (not shown in the figure), and the magnetic pole groups on the first rotor 301 and the second rotor 302 are circumferentially arranged around the rotating shaft. Specifically, the first rotor 301 is arranged on the periphery of the stator 300, and includes an outer sheath 3011, and eight radially magnetized permanent magnets are evenly distributed along the circumference of the inner wall of the outer sheath 3011 to form the first rotor pole group 3012. The number of poles is the same as that of the first winding 3002 . The second rotor 302 is arranged inside the stator 300 and includes a rotor core 3021. On the outer wall of the rotor core 3021, six radially magnetized permanent magnets are evenly distributed along the circumference to form the second rotor pole group 3022. The number of poles is the same as that of the second winding 3003 . After the drive shaft of the diesel engine is connected to the rotating shaft, it simultaneously drives the first rotor 301 and the second rotor 302 to rotate, so that AC voltages of different frequencies can be induced in the first winding 3002 and the second winding 3003, realizing the two-stage frequency modulation function of constant speed , to drive loads with different frequency requirements.

Claims (9)

1. A generator with constant speed and frequency modulation function, comprising a stator and a rotor, characterized in that the stator comprises a stator core, a first winding and a second winding, and both the first winding and the second winding are wound Manufactured on the stator core, the second winding is closer to the rotor in the radial direction of the stator than the first winding, and the rotor includes a rotating shaft and a first rotor pole group arranged in the circumferential direction of the rotating shaft and a second rotor pole group, the second rotor pole group is closer to the stator in the radial direction of the rotor than the first rotor pole group, forming the first rotor pole group and the second rotor pole group The polarities of the magnets of the rotor pole groups alternately change in respective circumferential directions, the number of poles of the first rotor pole group is different from that of the second rotor pole group, and the number of poles of the first rotor pole group is different from that of the second rotor pole group. The number of poles of the first winding is the same, and the number of poles of the second rotor magnetic pole group is the same as that of the second winding. 2 . The generator with constant speed and frequency modulation function according to claim 1 , wherein the stator is arranged on the periphery of the rotor, and the second rotor pole group is an integral magnetic ring. 3 . 3. The generator with constant speed and frequency modulation function according to claim 1, characterized in that, the first rotor pole group and/or the second rotor pole group are DC field windings. 4. The generator with constant speed and frequency modulation function according to claim 1, characterized in that, the magnetization directions of the first rotor pole group and the second rotor pole group are the same, both are radial or parallel method of magnetization. 5. The generator with constant speed and frequency modulation function according to claim 1, characterized in that, the magnets of the first rotor pole group and the second rotor pole group are evenly spaced in the circumferential direction. 6. A generator with constant speed and frequency modulation function, characterized in that it comprises a stator, a first rotor and a second rotor, the stator is arranged between the first rotor and the second rotor, and the stator It includes a stator core, a first winding and a second winding, the first winding and the second winding are both wound on the stator core, the first winding is radially close to the first rotor, the first The second winding is radially close to the second rotor, the first rotor and the second rotor have a common rotating shaft, and the first rotor is provided with a first rotor pole group arranged around the outer circumference of the stator, The second rotor is provided with a second rotor pole group arranged circumferentially around the inside of the stator, the number of poles of the first rotor pole group is different from that of the second rotor pole group, and the number of poles of the first rotor pole group is The number of poles is the same as that of the first winding, and the number of poles of the second rotor magnetic pole group is the same as that of the second winding. 7. The generator with constant speed and frequency modulation function according to claim 6, characterized in that, the first rotor pole group and/or the second rotor pole group are DC field windings. 8. The generator with constant speed and frequency modulation function according to claim 6, characterized in that the magnetization directions of the first rotor pole group and the second rotor pole group are the same, both are radial or parallel method of magnetization. 9 . The generator with constant speed and frequency modulation function according to claim 6 , wherein the magnets of the first rotor magnetic pole group and the second rotor magnetic pole group are evenly spaced in the circumferential direction.

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