WO2014021066A1

WO2014021066A1 - Power generation system

Info

Publication number: WO2014021066A1
Application number: PCT/JP2013/068805
Authority: WO
Inventors: 智道伊藤; 順弘楠野; 守木村
Original assignee: 株式会社日立製作所
Priority date: 2012-07-30
Filing date: 2013-07-10
Publication date: 2014-02-06
Also published as: DE112013003764T5; GB201419765D0; JP2014027824A; JP5988750B2; GB2518989A

Abstract

The purpose of the present invention is to provide a power generation system capable of improving continuity in operation when an abnormality occurs in a generator or a control device. In order to solve the abovementioned problem, the power generation system comprises: a generator (101) having a plurality of stator windings (10012, 10013) provided on a stator; power convertors (31, 32) provided on each stator winding; a sensor provided on each stator winding or on each power convertor to detect the state thereof; and an abnormality detection means for detecting the abnormality in the stator windings or the power convertors on the basis of the output from the sensor. The abnormality detection means outputs the presence or absence of an abnormality for each stator winding or each power convertor, and when the abnormality detection means outputs the presence of an abnormality, the power convertor in which the abnormality was detected or the power convertor provided on the stator winding in which the abnormality was detected cuts off the current of the stator winding.

Description

Power generation system

The present invention relates to a power generation system in which generated power is controlled by a power converter, and particularly relates to a system that improves operation continuity.

The wind power generation system is a pillar of renewable energy, and many capacities have been introduced all over the world beyond solar power generation systems and geothermal power generation systems. Here, since the generator in a wind power generation system is arrange | positioned in the nacelle etc. where the space was limited, there exists a restriction | limiting in enlargement. On the other hand, when trying to increase the power generation capacity, it is difficult to avoid an increase in the size of the rotor and the stator. Here, for example, there is one described in Patent Document 1 as one in which a plurality of rotors are provided in one generator to increase power generation efficiency.

According to the patent document, the generator of the power generation apparatus includes the first and second rotors, and at least one of the rotations is accompanied by a magnetic circuit formed by the stator and both rotors. One motive power is converted into electric power and output to the stator to generate electric power. The rotating magnetic field generated by the electric power generation and the first and second rotors maintain a predetermined collinear relationship between the rotation speeds of each other. Rotate while. In addition, two impellers are provided, and the first impeller converts the kinetic energy of the fluid into rotational kinetic energy, transmits the rotational kinetic energy to the first rotor, and rotates the first torque to rotate in one direction in the first rotation. Act on the child. The second impeller converts the kinetic energy of the fluid into rotational kinetic energy, transmits it to the second rotor, rotates it in the direction opposite to that of the first rotor, and increases the second torque larger than the first torque. Torque is applied to the second rotor.

JP 2009-185782 JP

In recent years, the capacity of wind power generation systems has continued to increase, and the height of wind turbine towers has exceeded 70 m. In addition, the number of installation locations is increasing not only on land but also offshore.

In addition, as the size of the windmill increases, it becomes difficult to repair in the event of equipment failure. Especially, since it is difficult to access the windmill offshore, it is necessary to prolong parts replacement and lengthen the maintenance cycle. It is desirable to reduce the maintenance burden.

Although it is also important for wind power generation system operators to reduce the maintenance burden, it is not something that can be repaired immediately when an abnormality occurs. Therefore, even if the power that can be generated decreases even after the abnormality occurs, the wind power generation system However, it is desirable to be able to continue power generation (because of higher operating rates).

However, in the power generation apparatus described in Patent Document 1, there is no description about operation continuity when an abnormality occurs in the generator or the controller.

Therefore, an object of the present invention is to provide a power generation system with improved operation continuity when an abnormality occurs in a generator or a control device.

In order to solve the above problems, a power generation system according to the present invention includes a rotor, a stator facing the rotor, a generator including a plurality of stator windings provided on the stator, An inverter disposed on the grid side, a converter disposed on the generator side, a capacitor disposed between the inverter and the converter, and a power converter provided for each stator winding; A sensor that is provided for each stator winding or the power converter and detects a state of the stator winding or the power converter, and based on the output of the sensor, the stator winding or the power converter An abnormality detection means for detecting an abnormality, and the abnormality detection means outputs whether or not there is an abnormality for each of the stator windings or the power converter, and is output when there is an abnormality from the abnormality detection means. If an error is detected, It has been the power converter, or abnormal, characterized in that interrupting the current of the stator winding in the power converter provided in the stator windings is detected.

According to the present invention, it is possible to provide a power generation system with improved operation continuity when an abnormality occurs in a generator or a control device.

1 is a schematic diagram of an entire power generation system according to Embodiment 1. FIG. It is a figure explaining the flow of control of the electric power generation system which concerns on Example 1. FIG. It is a figure explaining the structure of the power converter which concerns on Example 1. FIG. It is a figure explaining arrangement | positioning in the generator which concerns on Example 1. FIG. It is a figure explaining the magnitude | size of the apparatus in generator which concerns on Example 1. FIG. 1 is an axial sectional view of a generator according to Embodiment 1. FIG. FIG. 3 is an explanatory diagram of a power converter controller according to the first embodiment. FIG. 6 is an explanatory diagram of a power converter controller according to a second embodiment. It is a figure explaining the flow of control of the electric power generation system which concerns on Example 3. FIG. FIG. 6 is an explanatory diagram of a power converter controller according to a third embodiment. FIG. 10 is an explanatory diagram of a power converter controller according to a fourth embodiment. FIG. 10 is an axial sectional view of a generator according to a fifth embodiment. FIG. 10 is an axial sectional view of a generator according to a fifth embodiment. It is a figure explaining the flow of control of the electric power generation system which concerns on Example 6. FIG. FIG. 10 is an explanatory diagram of a power converter controller according to a sixth embodiment. It is a figure explaining the flow of control of the electric power generation system which concerns on Example 7. FIG. FIG. 10 is a diagram illustrating a configuration of a converter according to a seventh embodiment. FIG. 10 is a diagram for explaining an arrangement in a generator according to a seventh embodiment. It is a figure for demonstrating the principle by which the voltage in the neutral point pulsation which concerns on Example 7 is canceled.

Hereinafter, embodiments suitable for carrying out the present invention will be described with reference to the drawings. The following are merely examples of implementation, and are not intended to limit the embodiments of the present invention to the following specific embodiments. The present invention can be modified in various ways other than the following embodiments.

This embodiment will be described with reference to FIGS. In FIG. 1, the outline of the wind power generation system provided with the power generation system of a present Example is shown. As shown in the figure, the wind power generation system 1 includes a blade 10 that receives a wind force to obtain a rotational force, a hub 11 that transmits the rotational force of the blade 10 to a shaft 14, and a mechanical connection to the shaft 14. The power generation / converter unit 100 that converts mechanical input into electricity and transmits the generated power to the power system 2 is connected to the shaft 14 and includes a part of the shaft 14 and the power generation / converter unit 100 therein. The nacelle 60 and the tower 70 that supports the nacelle 60 so as to be rotatable in the horizontal direction are schematically configured. An anemometer 203 is installed above the nacelle 60, and the output of the anemometer 203 is input to a host controller 1000 described later. Further, the connecting portion between the hub 11 and the blade 10 is provided with a pitch angle adjuster 12 (described in FIG. 2) that adjusts the angle of the blade 10.

As shown in FIG. 2, the power generation / converter unit 100 is mainly configured by a power generator 101 to be described later,

power converters

31 and 32, and a power converter controller 2000 that is a controller of the

power converters

31 and 32. The power generated by the generator 101 is frequency-converted by the power converter and transmitted to the power system 2 via the cable 26.

Hereinafter, a detailed configuration of each part of the control system of the wind power generation system 1 and the power generation / converter unit 100 will be described.

The wind power generation system 1 is roughly divided into two controllers. One is a pitch angle command value φref and a total system transmission power command value (generated power command value) Pref of the

power converters

31 and 32 to control the rotation speed of the blade 10 according to the wind speed detected by the anemometer 203. The other controller is a power converter controller 2000 that controls the transmission power to the power system 2 in accordance with the generated power command Pref output from the host controller 1000.

The host controller 1000 receives an output v of the anemometer 203, a generated power value P calculated by the power converter controller 2000, a blade rotation angular velocity ω, and a power generation system abnormality signal L_ERR described later, and a pitch angle command value. φref and the total generated power command value Pref of the

power converters

31 and 32 are output.

The pitch angle command value φref output from the host controller 1000 is input to the pitch angle adjuster 12, and the pitch angle adjuster 12 adjusts the pitch angle of the blade 10 according to the input pitch angle command value φref. The wind receiving area of the blade can be changed by adjusting the pitch angle.

The generated power command Pref output from the host controller 1000 is input to the power converter controller 2000. The power converter controller 2000 controls both the

power converters

31 and 32 so that the total of the effective power received by the

power converters

31 and 32 from the generator 101 matches the power generation command.

In the host controller 1000, the power generation system abnormality signal L_ERR output from the power converter controller 2000 is active (in this embodiment, when the abnormality detection signal is 0, it is active, that is, when the abnormality detection state is 1, and when the abnormality detection signal is 1. Is negative, that is, in a normal state), it is determined that the blade deceleration torque maximum value obtained from the power generation / converter unit 100 has been halved, and the pitch angle command value φref and the total system transmission power command value Pref are limited respectively. To do. The restriction means that the pitch angle command value φref is controlled to reduce the wind receiving area, and the total system transmission power command value Pref is that the command value is reduced. By limiting the pitch angle command value φref, the rotational torque received from the wind can be reduced, and the blade 10 can be prevented from over-rotating.

Next, the power generation / converter unit 100 will be described in detail.

The generator 101 is a permanent magnet synchronous generator including two sets of three-

phase stator windings

10012 and 10013. The

power converters

31 and 32 are power converters having the same configuration. Note that the reason why the same configuration is used is that the members are intended to be general-purpose, and those having different configurations are not excluded. As will be described later, the inverter and the capacitor can be shared between the power converters.

The power converter 31 is connected to the generator 101 side, specifically, the converter 21 connected to the three-phase stator winding 10012, the inverter 23 connected to the power system 2 side, the converter 21 and the inverter 23 Between the smoothing capacitor 31cdc (and the voltage sensor 301 for detecting the stator winding voltage vst1, the current sensor 302 for detecting the stator winding current ist1, and the voltage across the terminals of the smoothing capacitor 31cdc. A voltage sensor 303 and a current sensor 304 for detecting the system output current ig1 are output to the power converter controller 2000. The output from the stator winding 10012 of the generator 101 is input to the power converter controller 2000. The power converter controller 20 receives the desired power and transmits the power to the output system 2. 0 calculates a gate signal Gate1 which is a control signal of the converter 21 and the inverter 23, and outputs it to the power converter 31. Specifically, it has the same frequency as the voltage vst1 of the stator winding 10012 and is delayed in phase. By causing the converter 21 to output the voltage, effective power is supplied from the stator winding 10012 to the power converter 31, and the power grid 2 is connected to the inverter 23 so that the voltage vdc 1 of the smoothing capacitor 31 cdc becomes a predetermined threshold value. A voltage having a phase advanced from the point voltage vg is output, and the active power obtained from the stator winding is transmitted to the power system 2.

The power converter 32 is connected to the generator 101 side, specifically, the converter 22 connected to the three-phase stator winding 10013, the inverter 24 connected to the power system 2 side, the converter 22 and the inverter 24 A smoothing capacitor 32cdc arranged between them, a voltage sensor 306 for detecting the stator winding voltage vst2, a current sensor 307 for detecting the stator winding current ist2, and a voltage sensor for detecting the voltage across the terminals of the smoothing capacitor 32cdc. 308 and a current sensor 309 for detecting the system output current ig2. The outputs of these voltage sensors and current sensors are also input to the power converter controller 2000 as in the case of the power converter 31. The power system 2 side of the inverter 23 and the inverter 24 is electrically connected, and is connected to the power system 2 after being connected. The measurement of the connection point voltage vg of the power system 2 is performed by the voltage sensor 305 that detects the connection point voltage. The power converter controller 2000 calculates a gate signal Gate2 that is a control signal of the converter 22 and the inverter 24 so that the power converter 32 receives desired power from the stator winding 10013 of the generator 101 and transmits the power to the output system 2. And output to the power converter 32. Specifically, by causing the converter 22 to output a voltage having the same frequency as the voltage vst2 of the stator winding 10013 and a phase lag, the effective power is supplied from the stator winding 10013 to the power converter 32, and smoothed. In order for the voltage vdc2 of the capacitor 32cdc to be a predetermined threshold, the inverter 24 outputs a voltage having a phase advanced from the connection point voltage vg of the power system 2, and the active power obtained from the stator winding is used as the power system 2 To send power.

The main circuit configuration and operation principle of the converter 21 and the inverter 23 will be described with reference to FIG. As described above, in this embodiment, the

power converters

31 and 32 have the same configuration, and the converters and inverters provided in the

power converters

31 and 32 have the same configuration. Therefore, the main circuit configuration and operation principle of the converter 22 and the inverter 24 are the same as those of the converter 21 and the inverter 23 although illustration and description are omitted.

In the present embodiment, the configuration of the converter 21 and the inverter 23 will be described using a 6-arm IGBT converter. The IGBT elements 21m to 21r and 23m to 23r constitute the arms of the converter 21 and the inverter 23, respectively. A gate drive signal is input from the power converter controller 2000 to the gates which are control electrodes of the IGBT elements 21m to 21r and 23m to 23r. When the gate drive signal is 0, the IGBT element is off, and when the gate drive signal is 1, the IGBT element is on.

By switching each IGBT element by inputting a PWM-modulated gate drive signal, the AC output power obtained from the stator winding 10012 of the generator 101 is output to DC power, and the DC power is output to the power system 2. Converted to AC power.

The current output from the stator winding 10012 of the generator 101 is determined by the difference between the generator induced voltage and the output voltage of the converter 21 and the leakage inductance of the stator winding 10012. The stator winding current is converted into a direct current by the converter 21, and the smoothing capacitor 31cdc is charged by the direct current.

The output current to the power system 2 is determined by the difference between the grid system voltage of the power system 2 and the output voltage of the inverter 23, and the impedance of the harmonic filter 23fil. The output current is converted from a direct current to an alternating current by switching of the inverter 23, and when the inverter 23 outputs active power to the system, the smoothing capacitor 31cdc is discharged.

The converter outputs a rectangular wave voltage by switching the IGBT element. Since this rectangular wave voltage causes the insulation deterioration of the generator, the converter 21 is connected to the generator 101 via the filter 21fil for limiting the voltage change rate.
As described above, the power converter 32 has the same configuration as that of the power converter 31, and thus redundant description is omitted.

Next, the generator 101 will be described with reference to FIGS. 4 and 5. FIG. 4 is a diagram displayed apart from the actual magnitude relationship for explaining the radial sectional view of the generator, and the actual magnitude relationship is close to FIG.

The generator 101 includes a rotor 502 including a permanent magnet, and two

stators

501 and 503 that sandwich the rotor 502 in the radial direction. The rotor 502 is mechanically connected to the shaft 14 and rotates counterclockwise between the

stators

501 and 503 as the blade 10 rotates (this does not exclude the specification of rotating clockwise). To do.

The stator 501 includes a plurality of magnetic poles and a stator winding 10012 wound around the magnetic poles. For the sake of brevity, the symbols (U1, V1, W1, N1, U2, V2, W2, and N2) shown on the winding terminals are electrically connected to each other. It shall be shown that

The stator 503 includes a plurality of magnetic poles and a stator winding 10013 wound around the magnetic poles. In addition, although the connection of terminal U2, V2, W2, N2 is not described, it is connected similarly to terminal U1, V1, W1, N1.

The magnetic flux generated by the permanent magnet of the rotor 502 is linked to the

stator windings

10012 and 10013 of both the stator 501 and the stator 503. As the rotor 502 rotates, an induced voltage is generated in the

stator windings

10012 and 10013.

By applying a voltage delayed in phase at the same frequency as the induced voltage from the

converters

21 and 22 to the

stator windings

10012 and 10013, the generator 101 passes through the

stator windings

10012 and 10013 to the

converters

21 and 22. Therefore, an effective current flows and power can be generated. Based on the above principle, power can be generated by both the

stator windings

10012 and 10013.

The generator shown in FIG. 4 has a configuration with a small number of magnetic poles in order to explain the configuration of magnetic poles and stator windings. Therefore, in the figure, the distances from the generator rotation center at the magnetic pole surfaces of the stator 501 and the stator 503 are greatly different. For this reason, there is a large difference in the rate of change of the magnetic flux linked to the

stator windings

10012 and 10013, and the induced voltages are greatly different.

However, in a wind power generation system with a rated rotational speed of about 20 rpm, the generator radius reaches several meters. In practice, therefore, the distance from the generator rotation center on the magnetic pole surfaces of the

stators

501 and 503 is relative as shown in FIG. Thus, the sizes of the

stators

501 and 503 are approximately the same. Therefore, a generator having a certain size such as the size can in principle generate approximately twice as much power as a generator including one stator having the same volume.

Subsequently, the operation of the wind power generation system 1 will be described.

The wind power generation system 1 obtains rotational energy when the blade 10 receives wind, and rotates the rotor 502 of the generator 101 in the power generation / converter unit 100 via the shaft 14 by the rotational energy.

The rotor 502 includes a plurality of permanent magnets 520 and 521 (described in FIG. 6), and an alternating induced voltage is generated in the

stator windings

10012 and 10013 of the generator 101 as the rotor 502 rotates. To do.

The

power converters

31 and 32 have a frequency equal to the AC voltage induced in the

stator windings

10012 and 10013 connected thereto, respectively, and output an AC voltage whose phase is delayed with respect to the induced voltage. The active power is received from the machine 101. The

power converters

31 and 32 convert the active power into a frequency equal to that of the power system 2 and transmit the power to the power system 2.

The adjustment of the input torque from the wind is performed by adjusting the pitch angle of the blade 10, and the pitch angle is adjusted by the host controller 1000 so that the rotation speed of the blade becomes a rotation speed command value corresponding to the wind speed.

Next, the generator configuration and the abnormality detection function of the power generation / converter unit 100 will be described in detail with reference to FIGS. In addition, FIG. 6 demonstrates a generator structure and FIG. 7 demonstrates the abnormality detection function.

The power generation system according to the present embodiment includes a power converter connected to each stator and a detector that detects an abnormality in the power generation system. When an abnormality is detected, the power converter or the stator winding is connected. The power converter is provided with a control system that cuts off the current of the stator winding and continues power generation with a sound stator winding and the power converter.

A method for supporting the rotor 502 and the stator 503 will be described with reference to FIG. FIG. 6 is an axial sectional view of the generator 101.

The stator 501 is configured to cover the outside of the generator 101, and is in contact with the shaft 14 that transmits the rotational force of the blade 10 to the rotor 502 via a bearing 506. A shaft 510 that is laid at the center of the stator 503 in the radial direction and supports the stator 503 via a spoke is fixed to the stator 501. The other end of the shaft 510 is in contact with the rotor 502 via a bearing 505. The rotor 502 is fixed to the shaft 14, and the other end of the rotor 502 is in contact with the shaft 510 through the bearing 504.

With this configuration, the rotor 502 and the stator 503 are supported by the stator 501 or the shaft 510 directly or indirectly via a bearing, and are provided with a rotor that is sandwiched between two stators in the radial direction. Can be formed.

The shaft 510 has a cylindrical configuration with a cavity inside, and the stator winding 10013 is drawn out of the generator through the cavity. With this configuration, the power converter 32 and the stator winding 10013 can be connected. Further, the

permanent magnets

520 and 521 are supported by being embedded in the rotor 502, and the generator 101 can support a permanent magnet that generates a magnetic flux linked to the stator winding. On the other hand, the

stator windings

10012 and 10013 can be fixed by being wound around the magnetic poles of the

stators

501 and 503.

Since the generator 101 in this embodiment includes a plurality of stators, a smaller generator can be configured as compared with a conventional generator having the same rated power.

In addition, since the

stator windings

10012 and 10013 in the present embodiment are installed in spatially separated locations in the generator as described above, abnormal heat generation due to short circuit or insulation deterioration occurs in one stator winding. Even if there is, since there is little influence on the other stator winding, there is a merit that it is possible to avoid an accidental expansion to a healthy stator winding.

Next, the power converter controller 2000 will be described with reference to FIG.

The power converter controller 2000 includes a multiplier 2100 that decomposes the generated power command Pref input from the host controller 1000 into generated power commands Pref 1 and Pref 2 of the

power converters

31 and 32, a subtractor 2101, and decomposed generated power A controller 2110 that calculates a gate signal Gate_01 of the power converter 31 so as to adjust the generated power of the power converter 31 according to the command Pref1, and a gate signal Gate_02 of the power converter 32 that adjusts the generated power of the power converter 32 according to Pref2. A controller 2111 for calculating the abnormality, an abnormality detector 2200 for performing an operation for detecting an abnormality of the power generation / converter unit 100 and outputting whether or not there is an abnormality, and a power converter according to the output of the abnormality detector 2200 Gate signal adjustment to adjust 31 and 32 gate signals And a

vessel

2301 and 2302.

The power command distribution method of the power converter controller 2000 will be described.

The generated power command value Pref input from the host controller 1000 is input to the multiplier 2100 and the subtractor 2101. Multiplier 2100 multiplies power generation command value Pref by a fixed value k satisfying 0 <k <1, and outputs the multiplication result (k * Pref) to controller 2110 and subtractor 2101.

The subtractor 2101 receives the generated power command value Pref and the multiplication result of the multiplier 2100 as input, and calculates the difference between the generated power command value Pref and the generated power command value Pref2 (= ( 1-k) * Pref) is calculated.

The fixed value k is a value designed according to the ratio of electric power that can be generated from the thermal design of the

stator windings

10012 and 10013 and the

power converters

31 and 32. In this embodiment, the fixed value k will be described with reference to FIG. As described above, since the electric power generated in the stator winding 10012 and the stator winding 10013 is expected to be approximately the same, the value is approximately equal to 0.5. Of course, the fixed value k may be changed according to the output ratio expected according to the specification.

The controller 2110 outputs from each current sensor / voltage sensor so that the active power calculation value P1 received by the power converter 31 from the stator winding 10012 coincides with the power command value Pref1 and the DC voltage vdc1 becomes a predetermined threshold value. The smoothing capacitor voltage vdc1, the power grid connection point voltage vg, the grid output current ig1, the output voltage vst1 of the stator winding 10012, the output current ist1 of the stator winding 10012, and the power command value Pref1 are input. The gate signal Gate_01 of the converter 31 is calculated. The active power calculation value P1 received from the stator winding 10012 is calculated by the product of the stator winding 10012 output voltage vst1 and the stator winding 10012 output current ist1. In addition to being used for the calculation in the controller 2110, P1 is output to the adder 2102.

The controller 2111 outputs from each current sensor / voltage sensor so that the active power calculation value P2 received by the power converter 32 from the stator winding 10013 coincides with the power command value Pref2 and the DC voltage vdc2 becomes a predetermined threshold value. The smoothing capacitor voltage vdc2, the power grid connection point voltage vg, the grid output current ig2, the output voltage vst2 of the stator winding 10013, the output current ist2 of the stator winding 10013, and the power command value Pref2 are input. The gate signal Gate_02 of the converter 32 is calculated. The effective power calculation value P2 received from the stator winding 10013 is calculated by the product of the output voltage vst2 of the stator winding 10013 and the output current ist2 of the stator winding 10013. P2 is output to the adder 2102 in addition to being used for calculations in the controller 2111. Further, the controller 2111 calculates the rotational speed ω of the generator 101 from the output voltage vst2 of the stator winding 10013 and the output current ist2 in addition to the calculation of the controller 2110, and outputs it to the host controller 1000.

The adder 2102 adds the active powers P1 and P2 and outputs the total generated power P of the generator 101 to the host controller 1000.

Hereinafter, the abnormality detector 2200 and the

gate signal adjusters

2301 and 2302 will be described.

The anomaly detector 2200 receives the output currents ist1 and ist2 of the stator windings 10012 and 1001 and outputs the gate adjustment signal CTRL1 of the power converter 31 and the gate adjustment signal CTRL2 of the power converter 32.

The abnormality detection calculation of the abnormality detector 2200 will be described.

The abnormality detector 2200 determines that there is an abnormality in the stator winding or the power converter when the absolute value of the output current of the

stator windings

10012 and 10013 is equal to or greater than a predetermined threshold, and outputs a gate adjustment signal. Change from 1 to 0.

Specifically, the abnormality detector 2200 includes

overcurrent detection calculators

2201 and 2202, and the overcurrent detection calculator calculates the absolute value of the stator winding output current and performs a comparison operation with a predetermined threshold value. To implement. The predetermined threshold value can be set to a value larger than the rated current value of the stator winding currents is1 and ist2, for example, a value that is 1.2 times the rated current, and the fixed threshold value calculated by comparing with the predetermined threshold value. When the absolute value of the child winding output current exceeds, an abnormality is detected, such as a short circuit of the stator windings 10012 and 1003 or a failure of the IGBT elements of the

power converters

31 and 32.

The abnormality detector 2200 outputs the gate adjustment signal CTRL1 of the power converter 31 and the gate adjustment signal CTRL2 of the power converter 32. The gate adjustment signal CTRL 1 is input to the gate signal adjuster 2301 and the gate adjustment signal CTRL 2 is input to the gate signal adjuster 2302.

The gate signal adjustment signal CTRL1 is a binary signal that is 0 when an abnormality is detected in the stator winding 10012 or the power converter 31, and is 1 otherwise. When an abnormality is detected, the gate signal Gate1 of the power converter 31 is set to 0 regardless of the value of the gate signal Gate_01, and all the IGBT elements of the power converter 31 are OFF, that is, the gate block is fixed. The current of the child winding 10012 is cut off.

The gate signal adjustment signal CTRL2 is a binary signal that is 0 when an abnormality of the stator winding 10013 or the power converter 32 is detected, and 1 otherwise. When an abnormality is detected, the gate signal Gate2 of the power converter 32 is set to 0 regardless of the value of the gate signal Gate_02, and all the IGBT elements of the power converter 31 are OFF, that is, the gate block is fixed. The current of the child winding 10013 is cut off.

In the power generation / converter unit 100, transmission of an abnormality detection signal to the host controller and an abnormality notification interface for maintenance personnel of the wind power generation system 1 will be described.

The outputs CTRL 1 and CTRL 2 of the abnormality detector 2200 are output to the OR calculator 2303 and the display 2700. The OR operator 2303 performs an OR operation on CTRL1 and CTRL2, and outputs the operation result to the host controller 1000 as an abnormality detection signal L_ERR.

As described above, when the abnormality detection signal L_ERR is 0, the host controller 1000 has approximately half the blade deceleration torque maximum value obtained by the power generation / converter unit 100 (the two stator windings have the same physique). Therefore, when there is a difference in capacity, the pitch angle command value φref and the total system transmission power command value Pref are limited. . By limiting the pitch angle command value φref, the rotational torque received by the wind can be reduced, and over-rotation of the blade 10 can be avoided.

Display unit 2700 receives CTRL1 and CTRL2 as input, and displays the name of the power converter that has detected the abnormality on a (liquid crystal) screen attached outside the power converter. That is, it plays a role of switching the display according to the output from the abnormality detector 2200. Here, the display on the (liquid crystal) screen may highlight the background of the name of the power converter that detected the abnormality in red, or the lamp indicating the failure of the power converter is turned on instead of the (liquid crystal) screen. May be. Further, the display 2700 communicates the occurrence of the failure via communication system 2701 to the communication terminal of the maintenance staff of the wind power generation system 1 located far away. With this configuration, the maintenance staff of the wind power generation system can know the abnormality of the power generation / converter unit 100 and can quickly make a repair plan.

In this embodiment, two stators in the generator are provided across the rotor, and a stator winding is provided for each stator. Therefore, power generation is performed on both the radially outer side and the inner side of the rotor. The space utilization factor of the generator can be improved, and a larger amount of generated power can be obtained with the same volume as the conventional generator. That is, the generator volume for obtaining a predetermined rated power can be reduced as compared with the conventional generator. Further, the number of stator windings provided in the stator does not have to be two, and can be increased. In that case, it is necessary to provide a power converter for each stator winding, and a sensor is provided for each stator winding or power converter to detect the state of the stator winding or power converter. It is also necessary to provide. After that, it suffices if there is an abnormality detection means for detecting an abnormality according to the output of the sensor.

In addition, a plurality of power converters that control the stator windings and generated power are provided. When an abnormality is detected in the power generation system, a healthy stator can be obtained by gate-blocking the detected power converter. Electric power generation can be continued for the winding and the power converter.

Furthermore, with regard to the arrangement of the plurality of stator windings, by arranging the rotor windings on the outer side and the inner side in the radial direction of the rotor (with the rotor sandwiched between them) The other healthy stator winding can be protected, and the healthy stator winding is not affected by the malfunction. Therefore, it is more suitable for the purpose of improving the power generation continuity.

Furthermore, the abnormality detection signal from the abnormality detection means is also displayed to the maintenance person of the wind power generation system, and it is possible to form a situation where the maintenance person can repair without delay while maintaining the power generation continuity. .

Furthermore, by providing an interface so that an abnormality detection signal can be transmitted from the abnormality detection means provided in the power generation / converter unit 100 to the host controller, the host controller outside the power generation / converter unit 100 allows the blade deceleration torque to be maximized by the power generation system. It is possible to calculate the pitch angle command value φref reflecting the decrease in the value, and to avoid over-rotation of the blade.

Example 2 will be described with reference to FIG. In the first embodiment, the abnormality of the power generation / converter unit 100 is detected by the overcurrent of the stator winding current. However, as shown in FIG. 8, the abnormality detector 2200 calculates the current antiphase component 2203. 2204, when the output of the anti-phase component calculator and the second predetermined threshold are compared, and the outputs of the

anti-phase calculators

2203 and 2204 are larger than the second predetermined threshold, the gate adjustment signals CTRL1 and CTRL2 are By providing the

comparators

2205 and 2206 that change from 1 to 0, it is possible to detect disconnection of the

stator windings

10012 and 10013 and avoid giving a large torque pulsation to the generator 101. Here, the second predetermined threshold is about 10 to 20% of the rated current of the

stator windings

10012 and 10013 in order to avoid improper detection of abnormalities due to imbalance of winding resistance and noise simultaneously with appropriate abnormality detection. It is desirable to set to. About another point, it is the same as that of Example 1, and duplication description here is abbreviate | omitted. In this embodiment, the same effects as those described in the first embodiment can be obtained.

Example 3 will be described with reference to FIGS. 9 and 10. In each of the above-described embodiments, the abnormality detection target is the overcurrent or current reverse phase component of the line current below the stator. However, abnormality detection may be performed based on an abnormal rise in the panel temperature of the inverter or converter. The power generation / converter unit 100 detects an abnormal rise in the temperature inside the panel of the inverter or converter, and gate-blocks the corresponding power converter.

When the IGBT element is not sufficiently cooled due to a failure of the cooling fan or the like, the temperature of the IGBT element or the panel rises. When the temperature rise of the IGBT is higher than the allowable temperature, there is a possibility of causing serious damage such as a burst or short circuit of the IGBT element module. By detecting an abnormal rise in the panel temperature and gate-blocking the corresponding power converter, further heat generation can be suppressed, and the power generation / converter unit 100 can be safely continued.

Specifically, as shown in FIG. 9, the

converters

21 and 22 and the

inverters

23 and 24 include

temperature sensors

350, 351, 352, and 353 that detect the temperature in the panel, and outputs T 11, T 12, T 21, T 22 of the temperature sensors. Is input to the power converter controller 2000. As shown in FIG. 10, the abnormality detector 2200 of the power converter controller includes

temperature determination units

2207 and 2208, which input T11 and T12, and the temperature sensor output value is larger than the third predetermined threshold value. For example, the power converter 31 is gate-blocked by changing the gate adjustment signal CTRL1 from 1 to 0. If the temperature sensor output value T21 or T22 is greater than the third predetermined threshold, the gate adjustment is performed. By providing the configuration in which the power converter 32 is gate-blocked by changing the signal CTRL2 from 1 to 0, damage due to overheating of the

power converters

31 and 32 can be avoided. Here, a temperature sensor may be installed in the immediate vicinity of the IGBT element, and an abnormal rise in the IGBT element temperature may be detected instead of the temperature inside the panel. About another point, it is the same as that of Example 1, and duplication description here is abbreviate | omitted. Also in this embodiment, the same effects as those described in the above embodiment can be obtained.

Example 4 will be described with reference to FIG. In addition to the abnormality detection described in the above embodiments, the power generation / converter unit 100 may detect an abnormal increase in the smoothing capacitor voltage. When an abnormality is detected, the corresponding power converter is gate-blocked. When the cable connecting the

inverter

23 or 24 to the power system 2 is disconnected, the corresponding inverter cannot transmit its rated power to the power system 2, and the power input from the converter connected to the inverter overcharges the capacitor. There is a possibility that. If the capacitor is overcharged, serious damage such as damage to the capacitor and damage to the IGBT element may occur.

Therefore, by detecting an abnormal rise in the smoothing capacitor voltage and blocking the corresponding power converter, further charging of the smoothing capacitor can be avoided, and stable operation of the power generation / converter unit 100 can be realized. Specifically, as shown in FIG. 11, the abnormality detector 2200 receives the smoothing capacitor voltages vdc1 and vdc2, and compares the smoothing capacitor voltage with a fourth predetermined threshold value to compare the

power converters

31 and 32.

DC overvoltage calculators

2209 and 2210 for detecting a DC overvoltage are provided. The

DC voltage calculators

2209 and 2210 change the gate adjustment signal CTRL1 from 1 to 0 if the smoothing capacitor voltage vdc1 is larger than the fourth predetermined threshold, and the smoothing capacitor voltage vdc2 becomes lower than the fourth predetermined threshold. If it is larger, the gate adjustment signal CTRL2 is changed from 1 to 0. By providing this configuration, the

power converters

31 and 32 can be protected from damage due to DC overcharge.

In addition, about the content as described in Examples 1-4, it is possible to use each independently, and it is also possible to use them together. Since each detects anomalies for different events based on different measured values, it can be used together to detect anomalies for various anomaly patterns and improve the accuracy of anomaly detection. .

Example 5 will be described with reference to FIGS. In each of the above embodiments, the case where the generator 101 is a permanent magnet synchronous generator has been described. However, an electromagnetic generator can also be used. Specifically, as shown in FIG. 12, the voltage of the electric power system 2 is stepped down by the transformer 55 and rectified by the diode rectifier 54, and then the rotor windings are passed through the

brushes

52 and 53 and the brush rings 50 and 51. Even if an exciting current is supplied to 10020, a linkage flux can be generated in the

stator windings

10012 and 10013 in the same manner as the permanent magnet.

Further, as shown in FIG. 13, the generator 101 is provided in the stator 501, and is provided in the coil 60 excited by the power system 2 and the rotor 502, and the alternating magnetic flux generated by the coil 60 is linked. A coil 61 that obtains AC power from the power system 2 in a non-contact manner, and a diode rectifier 54 that is provided in the rotor 502 and rectifies the AC voltage induced in the coil 61, and provides excitation current to the rotor winding 10020. It is possible to reduce the maintenance of the generator by providing a supply structure. That is, according to this configuration, the exciting current for the electromagnet generator is obtained from the induced current between the non-contact coil 60 and the coil 61, and it is not necessary to obtain the exciting current by contacting (directly) through the brush. Therefore, a brushless structure can be realized.

Even if expensive permanent magnets are not used as in this embodiment, a generator with high output density is configured, and even when a failure occurs in the power generation system, sound stator windings and power converters are used. High power generation continuity can be realized. Furthermore, in the case of the configuration shown in FIG. 13, it is possible to delete a brush that requires maintenance, so even when an electromagnetic generator is used, maintenance for brush replacement can be eliminated, and wind power generation with improved power generation continuity can be achieved. A system can be realized.

In each of the above embodiments, each power converter has been described with an inverter and a converter. However, as will be described later, inverters and capacitors arranged on the power system side may be shared. Is possible. That is, it is necessary for each power converter to include an inverter and a converter, but for each inverter, each power converter does not have to be independently provided.

Example 6 will be described with reference to FIGS. 14 and 15. In each of the embodiments described above, an example in which each power converter includes one inverter and a converter has been described. However, as illustrated in FIG. 14, the

power converters

31 and 32 have a configuration in which a DC unit is shared, The power generation / converter unit 100 may be configured to transmit the generated power to the power system 2 by a single inverter. In this case, since the DC circuit is common, the DC circuit voltages of the converter 21 and the converter 22 are equal. Since the DC circuit voltages become equal (the controller 2111 does not need to perform inverter control), the controller 2110 controls the inverter 23 based on the output value of the DC voltage sensor 303 to obtain the generated power from the generator 101. Can be transmitted to the electric power system 2. Further, since the inverter 24 is unnecessary, a current sensor for detecting the AC output current of the inverter 24 is not required. Therefore, with this configuration, it is possible to reduce the smoothing capacitor 32cdc on the power converter 32 side, the voltage sensor 308 for detecting the voltage of the smoothing capacitor 32cdc, and the current sensor 309 for system current detection.

When the configuration of FIG. 14 is realized, the power converter controller 2000 includes a gate signal Gate — 021 for driving the gate signal of the converter 21 and a gate for driving the gate signal of the inverter 23 as shown in FIG. The signal Gate — 023 is output, and the controller 2111 outputs a gate signal Gate — 022 that drives the gate signal of the converter 22, and only the gate signals of the

converters

21 and 22 are adjusted according to the output of the abnormality detector 2200. . The configuration of the controller 2000 that allows only the IGBT of the converter to be turned off by the output of the abnormality detector 2200 is a significant difference from the above-described embodiment, and the gate block in the configuration sharing the DC section is different from that in the inverter. The IGBT is not turned OFF, and is equivalent to controlling all the IGBTs in the converter to be turned OFF. Also in this case, when an abnormality is detected, the current of the stator winding is cut off by the power converter that detects the abnormality or the power converter that is connected to the stator winding that detects the abnormality. Continue power generation with windings and power converter.

According to the present embodiment, it is possible to reduce the number of voltage sensors for detecting the smoothing capacitor voltage and the number of current sensors for system current detection, and to realize abnormality detection as in the above embodiments while realizing a simple configuration. It is possible to do the same.

Example 7 will be described with reference to FIGS. 16 to 19. In this embodiment, instead of the

converters

21 and 22 in the power generation / converter unit 100,

converters

125 and 126 that are three-level converters are provided, and the stator winding 20013 of the generator 201 is The stator winding 20012 is arranged with a deviation of about 60 degrees in electrical angle.

The three-level converter can output a waveform closer to a sine wave than the two-level converter and can suppress dV / dt in the AC output voltage, thereby reducing the requirement for the insulation performance of the stator winding. On the other hand, when the power factor at the generator terminal is other than 1, a power fluctuation of three times the frequency of the AC output voltage occurs from the neutral point of the DC circuit, so that the capacitor voltages of the

converters

125, 126 and the inverter 123 are A large-capacitance capacitor must be mounted so as to be within the breakdown voltage range.

On the other hand, in this embodiment, by shifting the arrangement so that the

stator windings

20012, 20013 are shifted by 60 degrees in electrical angle, the voltage fluctuation that fluctuates the DC circuit neutral point cancels out, and the DC neutral point is offset. It is possible to reduce voltage fluctuation and reduce the capacitor capacity that the power converter 131 must be mounted.

Hereinafter, this will be described in detail with reference to FIGS.

In the power converter of the present embodiment, as shown in FIG. 16, the converters connected to the generator 201 are the three-

level converters

125 and 126, and their DC circuits are connected to each other.

Also in this embodiment, the main circuit configurations of the converter 125 and the converter 126 are the same, and only the configuration of the converter 125 will be described with reference to FIG. Of course, the converter 125 and the converter 126 do not always have to have the same main circuit configuration, and may have different configurations. By using similar parts, the types of parts can be reduced.

The converter 125 includes six IGBT elements and two diodes connected to a DC neutral point in one arm. By turning on and off the IGBT element, three levels of potentials can be output to the filter 121fil: the positive potential of the smoothing capacitor 131dcp, the DC neutral point potential, and the negative potential of the smoothing capacitor 131dcn.

When converter 125 outputs an AC voltage to filter 121fil, a difference occurs in the discharge power of smoothing capacitors 131dcp and 131dcn, and pulsation occurs.

FIG. 18 shows the configuration of the generator 201 of this embodiment. Compared with the generator 101 described in FIG. 4, the stator 603 is out of phase with the stator 601 by an electrical angle of 60 degrees. When the

stator windings

20012, 20013 are shifted by 60 degrees in electrical angle, the output voltages and output currents of the converter 125 and the converter 126 are both shifted by 60 degrees, so that the power pulsation is also equivalent to the fundamental wave and is shifted by 60 degrees. . An electrical angle of 60 degrees of the fundamental wave corresponds to 180 degrees, which is three times that of pulsating power having a frequency three times that of the fundamental wave. Therefore, the pulsation can be canceled by shifting the

stator windings

20012, 20013 of the generator 201 by 60 degrees in electrical angle.

This is shown in FIG. As shown in the figure, the pulsating power Pdcn1 flowing from the converter 125 to the DC neutral point and the phase of Pdcn2 are shifted by 180 degrees, so that the positive and negative are reversed, and the pulsating powers flowing into the midpoints of the capacitors 131pdcp and 131dcn are added together. As a result, it is offset.

According to the present embodiment, a generator having a high output density is configured, and even when a failure occurs in the power generation system, high power continuation using a sound stator winding and a power converter can be realized. Moreover, the winding insulation design of the generator 201 can be facilitated by using a three-level converter as the converter of the generator / converter unit 200. Furthermore, the pulsating power flowing from the three-

level converters

125 and 126 to the DC neutral point can be canceled by shifting the phases of the

stator windings

20012 and 20013 of the generator 201 by 60 degrees, which is a feature of this embodiment. It is possible to configure the power converter 31 with a small-capacitance capacitor.

Although the above embodiments have been described with reference to the wind power generation system, the application target is not necessarily limited to the wind power generation system except for the part related to the pitch angle control of the blades specific to the wind power generation system.

DESCRIPTION OF SYMBOLS 1 Wind power generation system 2 Electric power system 10 Blade 11 Hub 14

Shaft

31, 32

Power converter

21, 22, 25, 26

Converter

23, 24 Inverter 100 Electric power generation / converter part 101

Generator

501, 503 Stator 502

Rotor

301, 303, 305, 306, 308

Voltage sensor

302, 307, 309 Current sensor 1000 Host controller 2000 Power converter controller 2200 Abnormality detector 10012, 1003 Stator winding 10020 Rotor winding

Claims

A generator comprising a rotor, a stator facing the rotor, and a plurality of stator windings provided on the stator;
A power converter provided with an inverter disposed on the power system side, a converter disposed on the generator side, a capacitor disposed between the inverter and the converter, and provided for each stator winding When,
A sensor that is provided for each of the stator windings or the power converter and detects a state of the stator winding or the power converter;
An abnormality detecting means for detecting an abnormality of the stator winding or power converter based on the output of the sensor;
The abnormality detection means outputs whether there is an abnormality for each stator winding or power converter,
When an abnormality is output from the abnormality detection means, the stator winding is detected by the power converter in which an abnormality is detected or the power converter provided in the stator winding in which an abnormality is detected. A power generation system characterized by cutting off the current.
The power generation system according to claim 1,
Furthermore, a blade that rotates by receiving wind, a shaft that rotates as the blade rotates, and a pitch angle control means that controls the pitch angle of the blade,
The rotor rotates as the shaft rotates,
When the abnormality detection unit outputs an abnormality, the power generation system reduces the wind receiving area by adjusting the pitch angle of the blade using the pitch angle control unit.
The power generation system according to claim 1 or 2,
Two stators are provided across the rotor, and the stator winding is provided for each of the stators.
The power generation system according to claim 3,
The inverter and the capacitor in the power converter are shared between power converters, the converter is a three level converter,
The induction voltages induced in the stator windings provided for each of the two stators are equal between the stator windings, and the electrical angle between the stator windings is shifted by approximately 60 degrees. A power generation system characterized by that.
The power generation system according to any one of claims 1 to 4,
For each stator winding, the abnormality detection means includes an overcurrent detection means,
The sensor measures the current flowing through the stator winding and outputs the measured current value to the overcurrent detection means.
The overcurrent detection means compares the measured current value with a predetermined threshold value, and outputs an abnormality when the measured current value exceeds the threshold value.
The power generation system according to any one of claims 1 to 4,
For each stator winding, the abnormality detection means includes a negative phase calculator for calculating a negative phase component value of a current and a comparison means for comparing the negative phase component value calculated by the negative phase calculator with a predetermined threshold value. And
The sensor measures the current flowing through the stator winding and outputs the measured current value to the negative phase calculator.
The comparison unit compares the negative phase component value calculated by the negative phase calculator with a predetermined threshold value, and outputs an abnormality when the negative phase component value exceeds the threshold value. Power generation system.
The power generation system according to any one of claims 1 to 4,
For each stator winding, the abnormality detection means includes a temperature determiner,
The sensor measures the temperature of the inverter or the converter, and outputs the measured temperature to the temperature determiner.
The temperature determination device compares the measured temperature with a predetermined threshold value, and outputs an abnormality when the measured temperature exceeds the threshold value.
The power generation system according to any one of claims 1 to 4,
For each stator winding, the abnormality detection means includes an overvoltage calculator,
The sensor measures the voltage of the capacitor and outputs the measured voltage to the overvoltage calculator.
The overvoltage calculator compares the measured voltage with a predetermined threshold and outputs an abnormality when the measured voltage exceeds the threshold.
A power generation system according to any one of claims 1 to 8,
A first coil provided on the stator and excited by a power system;
A second coil that is provided in the rotor and obtains AC power from a power system in a non-contact manner by linkage of AC magnetic flux generated by the first coil;
A diode rectifier provided in the rotor and rectifying an AC voltage induced in the second coil;
A rotor winding provided on the rotor and supplied with an excitation current from the diode rectifier;
A power generation system, wherein a magnetic flux generated by an exciting current flowing through the rotor winding changes with time as the rotor rotates, thereby generating an alternating current in the stator winding.
The power generation system according to any one of claims 1 to 3, or 5 to 9, wherein the inverter and the capacitor in the power converter are shared between the power converters. .
The power generation system according to any one of claims 1 to 10,
In addition, a display device that displays whether or not it is abnormal, and a communication system connected to the display device,
The abnormality detection means outputs whether or not there is an abnormality in the display,
The indicator switches the display according to the output from the abnormality detection means,
When the abnormality detecting means detects an abnormality, the communication system transmits, via communication, that the abnormality has been detected to a communication terminal outside the power generation system.