CN200947563Y - Composite wind permanent magnet synchronous generator - Google Patents

Abstract

The utility model discloses a composite wind power permanent magnet synchronous generator, which includes a machine shell, a rotor and a stator which are arranged in the machine shell, the stator includes an inner stator and an outer stator, the inner stator and the outer stator are respectively arranged at the internal diameter side and the external diameter side of the rotor, an inner gas gap is formed between the internal diameter sides of the inner rotor and the stator, an outer gas gap is formed between the external diameter sides of the outer stator and the rotor; the inner stator armature windings and outer stator armature windings are respectively arranged on the inner stator and the outer stator. The utility model is a composite wind power permanent magnet synchronous generator with simple and compact structure, big power density and wide range of application, which is conductive to the wind power capture.

Description

Composite wind permanent magnet synchronous generator

technical field

The utility model mainly relates to the field of wind power generation equipment, in particular to a composite wind power permanent magnet synchronous generator.

Background technique

Wind power generation has significant environmental benefits, and countries all over the world are paying more and more attention to wind power generation. The two main components of a wind power system are the wind turbine and the generator. The speed of the wind turbine usually depends on the wind speed, and the wind speed is constantly changing. The change of the wind speed will cause the speed of the wind turbine to change, so the input power of the wind turbine obtained by the wind power generation system changes continuously with the wind speed. At present, the grid-connected wind power generation system mainly regulates the power of the wind turbine to adjust the input power of the generator, and the generator is connected to the grid through a grid-connected converter and a transformer. At present, the synchronous generator + uncontrollable rectification + inverter circuit used in wind power generation system cannot feed energy into the grid at low wind speeds; the synchronous generator + controllable rectification + inverter circuit has low power factor and cannot Energy is fed into the grid; synchronous generator + uncontrollable rectification + booster circuit + inverter circuit can feed power into the grid at low wind speeds, but the circuit control is more complicated and increases costs; , by controlling the number of generators cut into operation, the electric energy at low wind speed can be fed into the grid, but its structure is complex, the cost is high, and the control system is also relatively complicated. The generators of the direct-drive wind power generation system are large in power and large in size. Generally, these generators cannot make full use of the internal space structure of the generator, and the space utilization rate is small.

Utility model content

The technical problem to be solved by the utility model is that: aiming at the technical problems existing in the prior art, the utility model provides a composite wind-driven permanent magnet synchronous power generation with simple and compact structure, high power density, wide application range and favorable wind energy capture machine.

In order to solve the above-mentioned technical problems, the solution proposed by the utility model is: a composite wind-driven permanent magnet synchronous generator, which includes a casing, a rotor and a stator installed in the casing, and is characterized in that: the stator includes an internal stator The stator and the outer stator, the inner stator and the outer stator are installed on the inner diameter side and the outer diameter side of the rotor respectively, an inner air gap is formed between the inner stator and the inner diameter side of the rotor, and an outer air gap is formed between the outer stator and the outer diameter side of the rotor Gap; inner stator armature winding and outer stator armature winding are installed on inner stator and outer stator respectively.

The inner stator is press-fitted on the outer diameter side of the inner stator support, the outer stator is press-fitted on the inner diameter side of the casing, the rotor is supported by bearings, the bearings are installed on the inner stator support, and the rotor is provided with rare earth permanent magnets.

The front end of the casing is provided with an annular sealing baffle, and a sealing ring is provided between the annular sealing baffle and the rotor.

The inner stator armature winding and the outer stator armature winding are both 6-phase double Y-shifted 30° windings, and the outer stator double Y armature windings are respectively output in parallel after passing through a three-phase uncontrollable bridge rectifier circuit, and then output through the first balance The reactor Lp1 is used to balance the current of two sets of rectifiers in the outer stator armature winding; the double Y armature windings of the inner stator are output in parallel after passing through the three-phase uncontrollable bridge rectifier circuit, and the inner stator is balanced by the second balance reactor Lp2 The current of the two sets of rectifiers in the armature winding; the parallel connection output end of the inner stator armature winding and the parallel connection output end of the outer stator armature winding are then connected in parallel through the third balance reactor Lp3 to output direct current Ud, and the direct current Ud is passed through the inverter And connected to the grid after boosting.

Compared with the prior art, the utility model has the advantages of:

1. When the wind speed is low, the inner stator armature winding of the generator generates electricity independently, which can reduce the power loss of the generator and facilitate the capture of wind energy, and the generator can output higher voltage to feed the electric energy at low wind speed into power grid;

2. When the wind speed changes, the output voltage and frequency of the generator fluctuate within a relatively small range, which plays a good role in protecting the grid-connected converter;

3. The power density of the motor is high, the space structure is fully utilized, and the structure is compact;

4. The heat dissipation condition is good, the generator has a large surface, and the stator can dissipate heat well through the outer surface.

Description of drawings

Fig. 1 is the structural representation of the utility model;

Fig. 2 is the schematic diagram of main magnetic circuit in the utility model;

Fig. 3 is a wiring diagram of the stator winding in the utility model.

illustration

1. Chassis 2. Outer stator

3. Inner stator 4. Rotor

5. Bearing 6. Inner stator bracket

7. Sealing baffle 8. Outer stator armature winding

9. Outer air gap 11. Rubber sealing ring

12. Rare earth permanent magnet 13. Inner stator armature winding

14. Inner air gap

Detailed ways

The utility model will be further described below in conjunction with the accompanying drawings and specific embodiments.

As shown in Fig. 1 and Fig. 2, the compound type wind power permanent magnet synchronous generator of the present invention includes a casing 1 and a rotor 4 and a stator installed in the casing 1, the stator includes an inner stator 3 and an outer stator 2, and the inner stator The stator 3 and the outer stator 2 are installed on the inner diameter side and the outer diameter side of the rotor 4 respectively, an inner air gap 14 is formed between the inner stator 3 and the inner diameter side of the rotor 4, and an inner air gap 14 is formed between the outer stator 2 and the outer diameter side of the rotor 4. The outer air gap 9 makes the whole generator form a double air gap structure, and the inner stator 3 and the outer stator 2 are respectively equipped with an inner stator armature winding 13 and an outer stator armature winding 8 . In this embodiment, the inner stator 3 is press-fitted on the outer diameter side of the inner stator support 6, the inner stator support 6 is fixed on the casing 1, the outer stator 2 is press-fitted on the inner diameter side of the casing 1, and the rotor 4 is supported by the bearing 5 , The bearing 5 is installed on the inner stator bracket 6, and the rotor 4 is provided with a rare earth permanent magnet 12 to generate an air gap magnetic flux. A non-magnetic tight ring is sheathed on the outer surface of the rotor 4 to prevent the rare earth permanent magnet 12 from being thrown out by centrifugal force. The front end of the casing 1 is provided with an annular sealing baffle 7, and a sealing ring 11 is provided between the annular sealing baffle 7 and the rotor 4. The sealing ring 11 adopts a rubber sealing ring, which can play a role of windproof and dustproof, and extend the life of the whole machine. service life. Both the inner stator armature winding 13 and the outer stator armature winding 8 are 6-phase double Y-shifted 30° windings, and the outer stator double Y armature winding 8 respectively passes through a three-phase uncontrollable bridge rectifier circuit and then outputs in parallel, through the first The balance reactor Lp1 is used to balance the current of the two sets of rectifiers in the outer stator armature winding 8; the inner stator double Y armature winding 13 respectively passes through the three-phase uncontrollable bridge rectifier circuit and then parallel output, through the second balance reactor Lp2 Balance the current of the two sets of rectifiers in the inner stator armature winding 13; the parallel connection output end of the inner stator armature winding 13 and the parallel connection output end of the outer stator armature winding 8 are then connected in parallel through the third balance reactor Lp3 to output the direct current Ud , the DC Ud is connected to the power grid after being inverted and boosted. The outer stator armature winding 8 of the generator performs electromechanical energy conversion through the magnetic field of the outer air gap 9, and outputs electric energy; the inner stator armature winding 13 performs electromechanical energy conversion through the magnetic field of the inner air gap 14, and outputs electric energy; the air gap magnetic field is composed of rare earth The permanent magnet 12 produces the main magnetic circuit of the air gap magnetic field as shown in Figure 2. The main magnetic circuit passes through the N pole of the rotor rare earth permanent magnet 12, the outer air gap 9, the iron core of the outer stator 2, the outer air gap 9, the adjacent rare earth The S pole-N pole of the permanent magnet 12, the inner air gap 14, the iron core of the inner stator 3, the inner air gap 14, and the S pole of the rare earth permanent magnet 12 form a closed loop.

The composite wind power permanent magnet synchronous generator of the utility model has three different working forms, and can operate in three different states, as follows:

(1) When the wind speed is low, the inner stator armature winding 13 of the generator operates independently to generate electricity through the magnetic field of the inner air gap 14, and the output terminal of the outer stator armature winding 8 is disconnected. The maximum voltage output by the inner stator armature winding 13 is the rated voltage of the motor, and the maximum power is 1/3 of the rated power of the motor.

(2) When the wind speed is medium, the outer stator armature winding 8 of the generator operates independently to generate electricity through the magnetic field of the outer air gap 9, and the output terminal of the inner stator armature winding 13 is disconnected. The maximum output voltage of the outer stator armature winding 8 is the rated voltage of the motor, and the maximum power is 2/3 of the rated power of the motor.

(3) When the wind speed reaches the rated wind speed and above, the stator armature winding 13 and the outer stator armature winding 8 of the generator run simultaneously and output in parallel. The maximum output voltage is the rated voltage of the motor, and the maximum power is the rated power of the motor.

The maximum output voltages of the three working states of the compound type wind power permanent magnet synchronous generator of the utility model are equal, and the maximum output power increases in three stages. In this way, the generator can also output higher voltage at lower power output, which greatly reduces the fluctuation of the transmission voltage. , the power loss is small. When the generator of the utility model is in rated operation, 2/3 of the power is distributed on the outer stator 2, and the outer stator 2 dissipates heat through the outer surface of the motor, and the motor has good heat dissipation performance.

Specific working principle: see Figure 3, when the wind speed is low, the switch group Q2 is closed, the switch group Q1 is disconnected, and the 6-phase armature winding of the inner stator 3 of the generator generates power through the magnetic field of the inner air gap 14. At this time, the motor The speed is very low, and the output voltage and power are also low. As the wind speed increases, the motor speed increases and the output voltage rises. When the output voltage is higher than the rated voltage, the switch group Q1 is closed, and the switch group Q2 is disconnected at the same time, and the generator The 6-phase winding of the outer stator 2 generates power through the magnetic field of the outer air gap 9, the electromagnetic torque of the generator increases, and the output voltage drops; when the wind speed continues to increase, the output voltage of the motor rises, and when the output voltage is higher than the rated voltage, the switch group Q2 closes, and at the same time keep the switch group Q1 closed, the 6-phase armature winding of the outer stator and the 6-phase armature winding of the inner stator of the generator are connected in parallel to generate electricity at the same time, the electromagnetic torque of the motor increases, and the output voltage of the motor decreases; when the wind speed exceeds the rated When the wind speed is high, adjust the input power of the wind turbine by adjusting the pitch of the wind turbine to keep the output voltage of the generator stable. The working principle of the generator is further explained through a prototype running data as follows:

Table 1 below shows the output power value of a generator with a rated power of 1.5MW under different wind speeds:

Table 1 The power values of generators with a rated power of 1.5MW at different wind speeds wind speed(m/s) Generator output power (KW) 4.0 66.5 7.4 500.0 7.5 510.6 9.5 977.3 9.6 1000.0 13.0 1490.3 14.0 1499.2 15.0 1500.0 16.0 1500.0

The composite wind-driven permanent magnet synchronous generator with a rated power of 1.5 MW has a rated power of the outer stator armature winding 8 of 1 MW, and a rated power of the inner stator armature winding 13 of 0.5 MW. In Table 1, when the wind speed is lower than 7.4m/s, the inner stator armature winding 13 operates alone to generate electricity; when the wind speed is 7.4m/s to 9.6m/s, the outer stator armature winding 8 operates alone to generate electricity; s, the outer stator armature winding 8 and the inner stator armature winding 13 run in parallel to generate electricity; when the wind speed exceeds the rated wind speed of 15m/s, the generator will output constant power through the adjustment of the pitch of the wind turbine, and the output power will be the rated power of 1.5 MW.

Claims (5)

1, a kind of combined type wind power magneto alternator, it comprises casing (1) and is installed in casing (1) interior rotor (4) and stator, it is characterized in that: described stator comprises internal stator (3) and external stator (2), internal stator (3) and external stator (2) are installed in the internal side diameter and the outside diameter of rotor (4) respectively, air gap (14) in forming between the internal side diameter of internal stator (3) and rotor (4) forms outer air gap (9) between the outside diameter of external stator (2) and rotor (4); Be equiped with internal stator armature winding (13) and external stator armature winding (8) on internal stator (3) and the external stator (2) respectively.

2, combined type wind power magneto alternator according to claim 1, it is characterized in that: described internal stator (3) is fitted in the outside diameter of internal stator support (6), internal stator support (6) is fixed on the casing (1), external stator (2) is fitted in the internal side diameter of casing (1), rotor (4) is supported by bearing (5), bearing (5) is installed on the internal stator support (6), and rotor (4) is provided with rare-earth permanent magnet (12).

3, combined type wind power magneto alternator according to claim 1 and 2 is characterized in that: the front end of described casing (1) is provided with ring packing baffle plate (7), is provided with sealing ring (11) between ring packing baffle plate (7) and the rotor (4).

4, combined type wind power magneto alternator according to claim 1 and 2, it is characterized in that: described internal stator armature winding (13) is 6 two mutually Y with external stator armature winding (8) and moves 30 ° of windings, the two Y armature winding (8) of external stator are in parallel again output behind the uncontrollable bridge rectifier of three-phase respectively, comes the electric current of two groups of rectifiers in the balance external stator armature winding (8) by first interphase reactor (Lp1); The two Y armature winding (13) of internal stator are in parallel again output behind the uncontrollable bridge rectifier of three-phase respectively, comes the electric current of two groups of rectifiers in the balance internal stator armature winding (13) by second interphase reactor (Lp2); The output that is connected in parallel of the be connected in parallel output and the external stator armature winding (8) of internal stator armature winding (13) is again by the 3rd interphase reactor (Lp3) output DC (Ud) that is connected in parallel, direct current (Ud) through inversion with boost after link to each other with electrical network.

5, combined type wind power magneto alternator according to claim 3, it is characterized in that: described internal stator armature winding (13) is 6 two mutually Y with external stator armature winding (8) and moves 30 ° of windings, the two Y armature winding (8) of external stator are in parallel again output behind the uncontrollable bridge rectifier of three-phase respectively, comes the electric current of two groups of rectifiers in the balance external stator armature winding (8) by first interphase reactor (Lp1); The two Y armature winding (13) of internal stator are in parallel again output behind the uncontrollable bridge rectifier of three-phase respectively, comes the electric current of two groups of rectifiers in the balance internal stator armature winding (13) by second interphase reactor (Lp2); The output that is connected in parallel of the be connected in parallel output and the external stator armature winding (8) of internal stator armature winding (13) is again by the 3rd interphase reactor (Lp3) output DC (Ud) that is connected in parallel, direct current (Ud) through inversion with boost after link to each other with electrical network.

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