JP3003560B2 - Disaster prevention equipment and starting method of induction motor for disaster prevention equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an induction motor having two stators and two rotors as a load for an emergency power generation facility, and to use this induction motor as a fire-extinguishing pump or an exhaust pump having a squared load. It relates to disaster prevention equipment incorporated as a drive source for smoke fans.

[0002]

2. Description of the Related Art Generally, a simple starting method of an induction motor for driving a load is a straight-on starting and a star-delta starting. However, a general star-delta starting related to the present invention is as follows.
Although the current of the star connection at the time of starting can be suppressed as low as 1/3 of the delta connection, the starting torque is also reduced to 1/3 of the delta connection. In this starting method, the torque is
Since the torque gradually changes from the torque of / 3 to the rated torque, it is often used for pumps and blowers with a square-reduced load, and is a load optimal for the torque characteristics of the star-delta starting. Typical torque / current / input characteristics of the star-delta starting are shown in FIGS.

[0003] For this reason, an induction motor driven by a star delta is often used as a load of an emergency power generation facility in a disaster prevention facility. In other words, since the pump for fire extinguishing equipment of disaster prevention equipment has a squared reduction torque, it is used as a driving motor for the same.

[0004] The prime mover constituting the emergency power generation equipment of the disaster prevention equipment and the specified capacity (output) of the generator driven by the prime mover are changed from the start of the star-delta starting induction motor, which is the load, to the rated operation. The starting coefficient is selected based on the load current change rate and the input change rate of the induction motor during the starting period.

[0005] Therefore, not only the starting current during the starting period is reduced, but also the rate of change of the load current and the input during the star-delta switching during the starting period is reduced, so that the power generation required by the fire extinguishing equipment is reduced. And the capacity of the prime mover can be reduced. That is, if the starting coefficient can be improved, the equipment cost of the emergency power generation equipment can be reduced, and as a result, the equipment cost of the entire disaster prevention equipment can be greatly reduced.

In view of the above, in order to improve the starting coefficient, as an alternative to the conventional star-delta starting,
Although the starting coefficient has been reduced by closed star delta starting, reactor starting, condorfa starting, special condorfa starting, etc., they are very expensive switching devices at the time of starting, and equipment for emergency power generation equipment The current situation is that the switching device for the induction motor is expensive even if the cost can be reduced.

[0007]

From the above, the starting coefficient of the induction motor used for disaster prevention equipment is reduced by the conventional starter.
Improved over Delta and Closed Star Delta starting,
By realizing the same starting device as the switching device for closed star delta starting, the equipment cost of emergency power generation equipment can be set lower than that of star delta starting and other starting methods, and disaster prevention equipment It is a technical task to reduce the overall equipment cost.

[0008]

According to the present invention, the same number of times
Two rotors mounted on a pivot and each of the two rotors
And two stators wound with three-phase stator windings
An integrated induction motor and the induction motor
Fire fighting with driven fire pump or smoke exhaust fan
Equipment, an emergency power generator comprising a prime mover and a generator,
Connecting two stator windings to the emergency power generation facility
The two stator windings are connected in a star connection in parallel.
And connect a resistor in parallel to each phase of the star
Switch the resistance connection in series with each phase of the stator winding
Delta connection, remove resistance and connect delta connection independently
To delta connection,
A switching device for switching to parallel connection of lines is provided as a means for solving the above problem by providing disaster prevention equipment.

Also, two rotors provided on the same rotation shaft
And an induction motor consisting of two stators
Is the induction motor of the fire extinguishing system that drives the smoke exhaust fan,
In disaster prevention facilities connected to emergency power generators,
Power supply from the generator to the stator windings of the two stators
And each first into two three-phase stator windings Star - a step of feeding are connected in parallel connection, the two three-phase stator winding in the first connection to a second respective a step of connecting a resistor in parallel with the phase, the steps of the resistance in the respective phases of one of the three-phase stator winding to a third connected in series by a delta connection to power only one of the three-phase stator winding said Fourth, the three-phase connection in the third connection
Feeding with the exception take resistor connected in series with each phase of the stator winding
A process of electrodeposition, the problems by the starting method of proof <br/> disaster facility for an induction motor comprising the steps of each fifth to two three-phase stator winding to power connected in parallel with delta connection It was a means to solve it.

[0010] Either stator winding, preferably
Star connection of the stator winding on the side to be independently connected
In order to solve the above-mentioned problem, a method for starting an induction motor for disaster prevention equipment, which is connected to a power supply and started by supplying power , is used.

[0011]

First, the present invention relates to a disaster prevention facility in which an emergency power generation facility consisting of a prime mover and a generator is connected to a fire extinguishing facility consisting of an induction motor and a fire pump or a smoke exhaust fan. And two cage rotors mounted on the same rotation shaft, two stators each having a three-phase stator winding wound facing each of the two rotors, and two Phase stator winding is connected in delta from star connection in parallel.
The connection is switched to the parallel connection of the parallel delta connection via the single connection of the line, and the parallel connection of the star connection is changed to the single connection of the delta connection.
Switching to connection, connect a resistor in parallel with the star connection in parallel.
Since the switching device is connected and switched to a single connection of the delta connection to supply power, the switching device for starting can not only be manufactured in the same manner as closed star-delta starting, but also can be used for star-delta starting and closed star-delta. The starting coefficient was greatly improved as compared to the starting.

That is, according to the present invention, the operation is started by the parallel connection of the star connection, and the rated operation is performed by the parallel connection of the delta connection, and is constituted by two rotors and two stators. Since it is possible to use a half-power induction motor capable of continuously operating to supply power to only one of the stators, two three-phase stator windings can be connected as follows.

When two three-phase stator windings are connected in parallel in a star connection and started, the ratio of current and torque is 1/3 as compared with the parallel connection in a delta connection. When the operation is performed in parallel star connection and the rotation increases, at the intersection of the torque characteristic and the squared reduction load characteristic, a resistor is connected to make one stator winding a delta connection, and only this one stator winding is connected. Switch to power supply. In this delta connection, if the two stator capacitors are formed equally, the current flowing at this time is １ ／ of the parallel connection of the delta connection, and the parallel connection of the star connection is the parallel connection of the delta connection. Is 1/3 of
Both the current and the torque change from the ratio 1/3 to the ratio 1/2. Subsequently, when one of the stator windings is operated in the delta connection and the rotation further increases, at the intersection of the torque characteristic and the squared reduction load characteristic, the parallel connection of the delta connection by the next two three-phase stator windings is performed. Switch to connection. At this time,
Both the current and the torque change from the ratio 1/2 to the ratio 1.

The change in torque and current in the first switching is 1 /
The change from 3 to 1/2, which is so small that it cannot be compared with the large change from 1/3 to 1 in the conventional star-delta switching start. In addition, switch by connecting a resistor
The change from 1/3 to 1/2 is very slow
You. The change of torque and current at the next switching is from 1/2 to 1
However, at this time, the load current is already close to the rated speed and the load current is small, and the effect of the change from 1/2 to 1 on the starting coefficient is extremely small as compared with the conventional one. ing. The change of the input due to the switching is the same as the voltage / current.

When the fire prevention equipment incorporating the fire extinguishing equipment as described above is driven by the starting method using the induction motor and its switching device according to the present invention, the starting coefficient can be greatly improved. In selecting the power generation equipment for use, the rank of the generator / motor output based on the output of the induction motor can be made lower than before. Furthermore,
The switching device of the induction motor is based on a simple opening / closing device, and the price of the entire induction motor including the switching device itself is low, so that the entire disaster prevention equipment can be provided at a low price. The real economic effect is that the price can be significantly reduced by one million yen per disaster prevention facility, and the introduction of multiple units will result in a large budget margin when investing in equipment, resulting in an economic ripple effect. Is extremely large.

More specifically, the induction motor used in the disaster prevention equipment of the present invention is switched and started as follows. That is, the switching device first supplies power by connecting two three-phase stator windings in parallel in a star connection, and secondly supplies two three-phase stator windings in the first connection. Thirdly, a resistor is connected in parallel to each phase of one of the three-phase stator windings, a resistor is connected in series to each phase of one of the three-phase stator windings, and a delta connection is made to feed only the one three-phase stator winding. 4 removes the resistor connected in series in the third connection, and
Each of the three-phase stator windings was connected in parallel with a delta connection to supply power and start the induction motor.

That is, according to the present invention, the torque and current are reduced from 1/3 to 1 by adopting a closed star delta type in which a resistor is connected in the second to fourth connection modes of the switching device. / 2, the most influential period of the starting coefficient is changed in a fine and gradual manner, so that the closed-star delta switching of the conventional single stator can be performed.
Before and after parallel connection of star connection and parallel connection of delta connection
In addition, more gradual switching is possible, and the switching can be performed without disconnection of the load current, and it is possible to obtain a method of starting a gradual torque and current change that could not be seen in the prior art. Was.

Before switching by the switching device, one of the three stator windings, which is the first connection, is connected in parallel with a star connection in order to supply power. Delta connection , preferably with only one feed
By adding a switching sequence in which the stator winding on the other side is connected to a star connection and supplying power, it is possible to start from a smaller torque at a lower current, and to smoothly start a fan or pump with squared torque reduction characteristics. Can be
A starting torque most suitable for starting can be obtained. In other words, by adding a switching order of connecting one of the stator windings to the star connection and supplying power, the two three-phase stator windings are connected in parallel with the star connection to supply power more than those supplied. The torque is で, and the current and torque when the two three-phase stator windings are connected in parallel by delta connection and supplied with power are set to 1, 、, 1/3,
By changing to 1/2 and 1, the switching can be performed more quickly than the closed star delta in the conventional single stator. In addition, by adopting a closed star delta type in which a resistor is connected to the third to fifth connection modes, the torque characteristics during the period in which the starting coefficient is most affected are finely and gradually changed.

Here, the switching device sequentially switches the connection from the parallel connection of the parallel star connection to the parallel connection of the delta connection by two three-phase stator windings. it can be made to go switched while feeding the three-phase stator windings of the. Therefore, the switch is always intended for half of the normal stator winding, and the switch required for switching can be realized inexpensively as long as it has a half electric capacity.

In addition, the switching speed of the switching device is controlled by the rotation speed,
The sequential switching based on a time limit, a load torque or the like can be realized by a conventionally known technique.

[0021]

1 to 12 show a preferred embodiment according to the present invention.
This will be described below. First, the configuration of the disaster prevention equipment of the present invention will be described with reference to FIG. 1. The disaster prevention equipment indicated by reference numeral 1 includes an emergency power generation equipment 2 and a fire extinguishing equipment 3, and the emergency power generation equipment 2 is a motor (engine) 4. The motor 4 and the generator 5 have rotating shafts connected to each other. The fire extinguishing system 3 is electrically connected to the pump device 7 which is a square-reducing load, the induction motor 6 which is the driving source thereof, and the connection and connection of the three-phase stator windings 19 and 20 of the induction motor 6. The induction motor 6 and the pump device 7 are connected with a rotating shaft, and the induction motor 6 is started by the switching control of the switching device 8. Further, the switching device 8 is supplied with the generated power of the emergency power generation equipment 2, and is supplied from the switching device 8 to the induction motor 6, and the pump device 7 is rotated by the rotation of the induction motor 6.

Next, the prime mover 4 and the generator 5 of the disaster prevention equipment 1
The configuration of the induction motor 6 as an element for determining the output selection and the method of starting the induction motor 6 by the switching device 8 will be described below. First, the configuration of the induction motor 6 will be described with reference to FIG. In the induction motor 6, two rotor cores 10 and 11 are axially mounted on a rotating shaft 9 at an arbitrary interval, and rotor conductors 12 and 13 are provided on the rotor cores 10 and 11, respectively. The child conductors 12 and 13 are the rotor cores 10 and 1
1 is formed into a cage by short-circuiting the short-circuit rings 14 and 15 on both sides to form an integral rotor 16 having two rotors. Further, the rotor cores 10, 11
And stator windings 1 and 2 wound around the stator cores 17 and 18 at an arbitrary interval facing each other.
9 and 20 constitute the stators 21 and 22.

A machine frame 23 in which the stators 21 and 22 are provided.
On both sides, a bearing board 25 fitted with a ball bearing 24 and a ball bearing 26 are fitted and a bearing board 27 is fitted. The ball bearings 24 and 26 support the shaft 9 of the rotor 16. The stators 21 and 22 are concentrically rotatable.

Next , a switching device 8 according to the present invention in which the starting coefficient of the fire extinguishing system 3 by the induction motor 6 is improved will be described with reference to FIGS. As for the switching control of the switching device 8, it is also effective to detect any one or a plurality of rotation speeds, load currents, temperatures, time limits, etc. according to the load connected to the induction motor 6, and control the switching according to the values. Means.

First, a connection diagram between the switching device 8 and the stator windings 19 and 20 of the induction motor 6 is shown in FIG. One of the three-phase stator windings 19 is connected to power supplies R, S, and T (emergency power generator 2) via a main switch MB and a switch MC1, and the other of the three-phase stator windings 19 is connected to the other. Switch MC for star connection
Connected to S. Further, the three-phase stator winding 20 is provided between the main switch MB and the switch MCS.
9 in parallel with a switchgear MC2. This simultaneously three-phase stator windings 20 is static by the switch MCS - can be connected.

The stator windings 19 and 20 connected in parallel are both delta-connected via a switchgear MCD. In addition, a resistor R is connected to the delta connection circuit via a switch MCR so that a resistor R can be connected in series or in parallel to each phase winding when the delta connection is made.

Next, if each switching device is controlled by another sequence circuit, the opening and closing of the switching device at the time of starting can be automated according to time or rotation speed. Here, a first embodiment of the sequence control in the case of controlling by time will be described with reference to FIGS.

The sequence circuit is shown in FIG. 4. In FIG. 4, a symbol of a normal sequence circuit is used, and the symbol ○ indicates a solenoid, and the English symbol of a switch is operated by the solenoid having the same symbol. Is shown. Hereinafter, the operation of the circuit shown in FIG. 4 will be described. When the push button switch PB1 is pressed, the solenoid MCS is energized, and each switch MCS is activated, so that the solenoid MC1 is energized and the switch MC1 is activated and the solenoid MC1 is activated.
Apply power to MC2. With this, solenoid MCS and solenoid MC
When the power is supplied to the solenoid 1 and the solenoid MC2, the motor is started by the star connection in parallel connection (FIG. 5 (1)). At the same time, the solenoid TRS is also energized, and the timed switch TRS is turned on within 30 seconds, for example, after 20 seconds. Also, the solenoid RY is not energized because the switch MCS connected in series is opened by the solenoid MCS.

As shown in the example, when 20 seconds elapse after the start, the time switch TRS closes and the solenoid MCR is energized. From the moment of energization, the switch MCR closes, and a resistor can be connected in parallel to the star-connected parallel connection (Fig. 5 (2)). However, at the next moment, the switch MCR is activated by energizing the solenoid MCR to disconnect the solenoid MCS from the power supply. Delta connection in which the phase stator winding 19 and the resistor R are connected in series (FIG. 5 (3)
).

Subsequently, since the solenoid MCS is disconnected from the power supply, the switch MCS is operated, and the solenoid RY is energized, and the solenoid MCD and the solenoid TRD can be energized by the operation of the switch RY. To energize the solenoid TRD, set the timed switch TRD to 10
It is turned ON within 5 seconds, for example, within 5 seconds. The state at this time is as shown in FIG. When the switch RY is activated, the solenoid MCD is also energized.When the switch MCD is activated, the solenoid TRS is disconnected from the power supply, the timed switch TRS is opened, the solenoid MCR is disconnected from the power supply, and the switch MCR is disconnected. Operates. The operation of the switch MCR releases the resistance R. (Fig. 5 (5)) Simultaneously, the solenoid MCD is also energized and delta connection is established, and when the timed switch is closed after 5 seconds, the solenoid MC2 is energized and the switch MC2 is closed and the delta connection is connected in parallel (Fig. 5 (6) )) And finally the connection for rated operation.

As described above, the time for connecting the resistor R is very short, but it is an effective method for reducing the voltage fluctuation due to the switching. As can be understood from such switching, one of the three-phase stator windings 19 remains connected to the power supply from the beginning to the end. Is repeated, so that the entire voltage is not cut off even instantaneously unlike the conventional star-delta starting. Further, as described above, the voltage fluctuation is suppressed via the resistor for switching, so that
The starting coefficient for the prime mover or generator has been greatly improved.

Next, a second embodiment of the sequence suppression in the case of controlling by time will be described with reference to FIGS. The difference from the first embodiment is that only one of the stator windings is star-connected and connected to a power source to start the motor. The connection has been made, but the switch MC1
Switch MC2 is newly added as MC1. Along with this, a timed switch TI and a solenoid TI for setting the start time when only one of the stator windings is star-connected and connected to the power supply to start are newly provided. The time switch and solenoid are indicated as T2, and the time switch and solenoid in delta connection are indicated as T3. In addition, the operation of the sequence circuit will be described only for parts different from those in the first embodiment.

In the sequence circuit of FIG. 6 connected as described above, when the push button switch PB1 is pressed, the solenoid MCS is energized, and each switch MCS is activated, so that the solenoid MC1 is energized and the switch MC1 is turned on. Activated switch
The three-phase stator winding 19 in the star connection is energized by the MCS, and is started in the star connection of one of the three-phase stator windings 19 shown in FIG. At the same time, the solenoid T1 is energized by the switch MCD.
It is activated after a few seconds. Timed switch after 3 seconds
By energizing the solenoid RY1 by T1, and energizing the solenoid T2 and the solenoid MC2 when the switch RY1 is closed, the three-phase stator windings 19 and 20 are connected in parallel with the star connection shown in FIG. The connection time is determined by the timed switch T2. Note that the subsequent connections are the same as those in FIG.

The torque characteristic of the induction motor due to the switching of the connection is, as shown in FIG. 8, a torque characteristic A in a state where one three-phase stator winding is star-connected and supplied with power.
, A torque characteristic A when two three-phase stator windings 19 and 20 are star-connected and connected in parallel, a torque characteristic B when one of the three-phase stator windings is delta-connected, and A torque characteristic C in a state where two three-phase stator windings are connected in parallel by delta connection can be roughly classified into four types. 9 and 10 show current characteristics and input characteristics in the four connections. In FIG. 8, the load torque Tr and the rated torque T are specified, and the three-phase stator windings are switched at the intersections (a '), (a), and (b) of the load torque Tr and the torque of the induction motor. However, in the embodiment of the present invention, the switching is performed according to the time limit, so that the connection switching timing is determined by the time from the start.

The induction motor according to the present invention has a torque characteristic A in the first embodiment and a torque characteristic A 'in the second embodiment.
However, since the load torque at the time of startup is very small as a load characteristic of the squared reduction load, the torque at the time of startup of the induction motor is 1 / the value of when the delta connection is connected in parallel.
Even if the torque is 3 (first embodiment) or 1/6 (second embodiment), it starts without any problem. Then, the rotation speed is increased and, in the second embodiment, the torque characteristic is switched to the torque characteristic A from the time until the vicinity of the intersection (a ') of the load torque Tr and the torque characteristic A', for example, three seconds after the start. The first embodiment measures the vicinity of the intersection (a) between the load torque Tr and the torque characteristic A.
For example, 20 seconds are set in the timed switch TRS and activated, and one of the three-phase stator windings 19 is delta-connected from the star-connected parallel connection to form a three-phase stator winding 19.
Is switched to the torque characteristic B for supplying power only to the motor. Up to the torque characteristic B, as described above, the switching method without completely interrupting the voltage applied to the three-phase stator winding 19 via the resistor R, that is, by the switching device 8 in the first embodiment. By the switching from the second to the fifth, during this time, the torque characteristic is momentarily changed between the torque characteristic A and the torque characteristic B in four stages, and the change of the torque characteristic from A to B is small. Because of this, changes in current and input are also small. In conventional star-delta starting, the load torque Tr
From the point of intersection (a) to the point of intersection (c), it can be understood that the rate of change is large and the starting coefficient is very poor as compared with the present invention.

When the induction motor is switched to the torque characteristic B, the rotation of the induction motor is increased by the torque characteristic B, and one of the three-phase stator windings 19 is delta-connected near the intersection (b) between the load torque and the torque characteristic B. From the torque characteristic B for supplying power only to the three-phase stator winding 19, two three-phase stator windings 19,
20 is switched to the torque characteristic C connected in parallel by delta connection. This is done by setting in the timed switch TRD the time from when the torque characteristic is switched from the torque characteristic A to the torque characteristic B to the time when it is accelerated by the torque characteristic B and near the intersection (b), for example, 5 seconds, and then activates it. Can be switched from the torque characteristic B to the torque characteristic C.

FIGS. 9 and 10 show the switching between the current characteristic and the input characteristic of the motor by switching the torque characteristic of FIG. 8 as described above. It is clear that the ratio has become smaller than (c). Although the torque characteristic of the present invention is used in the description of the conventional star-delta starting, the induction motor of the present invention is switched to the star and the delta by parallel connection. Is slightly different from the torque characteristic of the star-delta switching in the above.

The induction motor 6 according to the above-described starting method, the switching device 8 therefor, and the induction motor 6
11 and 12 show how much the output of the prime mover 4 and the generator 5 of the emergency power generation facility 2 was reduced with respect to the fire extinguishing facility 3 driven by the conventional line start and reactor start-up. , Star delta starting,
The results are shown in comparison with the closed delta start and the condorfa start. FIG. 11 shows the generator output (KV
A), and FIG. 12 shows the motor output (PS) with respect to the motor output (KW).

Now, in the disaster prevention equipment thus configured, the starting coefficient can be greatly improved by the new configuration of the induction motor and the new starting method. Therefore, the output rank to select both the generator to be incorporated and the prime mover should be selected. Can be lowered. The condition is that the generator is a 4-pole generator and the prime mover is a normal diesel engine. As is apparent from this figure, it is possible to further improve the condorfa starting, which is considered to have a relatively improved starting coefficient, and to select a generator output and a prime mover output smaller than the conventional one. In particular, this tendency becomes more remarkable as the motor output increases, and the difference from other starting methods becomes larger.

The fact that a generator or a prime mover with a smaller output can be selected means that there is a difference in the amount of capital investment. In particular, even if the motor output is small, when viewed as a disaster prevention facility, if the rank is reduced by one, the difference in the amount of money will be at least 1 million yen, and the larger the output, the larger the difference in the amount . An example of this difference is shown in Table 1.

[0041]

[Table 1] This will be compared between a fire extinguishing system using a fire extinguishing pump unit driven by an induction motor 22KW and an emergency generating system using a prime mover and a generator for supplying power to the fire extinguishing system. Specifically, a fire extinguishing system driven by a conventional star-delta starting switching device, a fire extinguishing system driven by a closed star-delta starting switching device, and a fire extinguishing device driven by a switching device of the present invention and an induction motor are provided. , The estimated value of the fire extinguishing equipment itself, the output of the emergency power generation equipment required for the fire extinguishing equipment, the estimated value of the equipment and the total amount and budget ratio were clarified.

In the conventional star-delta starting, a basic set of a fire extinguishing pump, a 22 kW output induction motor and a switching device constituting a fire-extinguishing facility and a switching device of 2 million yen is required. Emergency power generation equipment with a power generation output of 85 KVA is about 12 million yen, and the total disaster prevention equipment is about 14 million yen. This star
There is a closed star delta start in which the starting coefficient of the delta start is improved. In this case, the resistance required for starting the motor in the closed star delta is added to the fire extinguishing equipment, so the fire extinguishing equipment costs about 2.5 million yen, and the power generation output of the emergency power generation equipment requires 85 KVA. The generator output is not different from the star-delta start of the same output.The closed star-delta start certainly improves the starting coefficient.However, when combined as a disaster prevention facility, due to the relationship with other equipment, The range corresponding to the generator output corresponding to the fire extinguishing system is the same for the star delta start and the closed star delta start. Therefore, when the closed star delta is started, the disaster prevention equipment costs 14.5 million yen. However, the fire prevention equipment according to the present invention requires about 2 fire extinguishing equipment.
Although it is a little expensive at 800,000 yen, emergency power generation equipment can be ranked down to 50 KVA, which is about 9 million yen. Therefore, the total cost is 11.8 million yen, and a price reduction of 18% (approximately 2.2 million yen) compared with the star-delta starter and a 22% reduction (approximately 2.7 million yen) of a closed-star delta starter can be achieved.

[0043]

As described above, when the disaster prevention equipment is constructed according to the present invention, the starting coefficient can be greatly improved. Therefore, when selecting the emergency power generation equipment of the disaster prevention equipment, the generator and the generator based on the output of the induction motor are used. The rank of the motor output can be set to an output lower in number than the conventional output. Furthermore,
The switching device of the induction motor is based on a simple opening and closing device, and the price of the entire induction motor including the switching device itself is low, so that the entire disaster prevention equipment can be provided at a low price. The real economic effect is that the price can be significantly reduced by one million yen per disaster prevention equipment, and the introduction of multiple equipment will result in a large budget margin when investing in equipment, and the economic ripple effect Is extremely large.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a disaster prevention facility of the present invention.

FIG. 2 is a sectional view of an induction motor according to the disaster prevention equipment of the present invention.

FIG. 3 is a connection diagram of a stator winding and a switching device of the induction motor according to the disaster prevention equipment of the present invention.

FIG. 4 is a sequence circuit for controlling a switching device of a three-phase stator winding of the induction motor.

FIG. 5 shows how the three-phase stator winding is switched.

FIG. 6 is another example of a sequence circuit.

FIG. 7 shows how the three-phase stator winding is switched by the sequence circuit shown in FIG. 6;

FIG. 8 is a torque characteristic diagram of an induction motor using the disaster prevention equipment of the present invention.

FIG. 9 is a current characteristic diagram of an induction motor using the disaster prevention equipment of the present invention.

FIG. 10 is an input characteristic diagram of an induction motor using the disaster prevention equipment of the present invention.

FIG. 11 shows a generator output characteristic with respect to an induction motor output.

FIG. 12 shows a motor output characteristic with respect to an induction motor output.

FIG. 13 is a torque characteristic diagram of an induction motor by conventional star-delta starting.

FIG. 14 is a current characteristic diagram of an induction motor driven by a conventional star-delta starting.

FIG. 15 is an input characteristic diagram of an induction motor by conventional star-delta starting.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Disaster prevention equipment 2 Emergency power generation equipment 3 Fire extinguishing equipment 4 Prime mover 5 Generator 6 Induction motor 7 Pump device 8 Switching device 9 Rotating shaft 10 Rotor core 11 Rotor core 12 Rotor conductor 13 Rotor conductor 14 Short circuit ring 15 Short circuit ring DESCRIPTION OF SYMBOLS 16 Rotor 17 Stator core 18 Stator core 19 Stator winding 20 Stator winding 21 Stator 22 Stator 23 Machine frame 24 Ball bearing 25 Bearing board 26 Ball bearing 27 Bearing board

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-64-47287 (JP, A) JP-A-58-141687 (JP, A) JP-A-3-277154 (JP, A) JP-A 9-141 19116 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H02K 16/00 H02K 17/30 H02P 1/32

Claims (4)

(57) [Claims] 1. Two rotors mounted on the same rotating shaft, and
The three-phase stator winding is wound facing each of the rotors.
An induction motor integrated with two stators,
Fire pump or flue gas driven by induction motor
A fire extinguishing system including a fan, an emergency power generator including a motor and a generator, and two stator windings connected to the emergency power generator.
The two stator windings are connected in a star connection in parallel.
And connect a resistor in parallel to each phase of the star
Switch the resistance connection in series with each phase of the stator winding
Delta connection, remove resistance and connect delta connection independently
To delta connection,
Disaster prevention facility, characterized in that it comprises a switching device for switching the parallel connection of the line, the. 2. The stator winding on the side where the delta connection is solely connected.
Start the line with a single star connection, and then
Switch to parallel connection of the delta connection, and
Switch to parallel connection of delta connection via German connection
The disaster prevention equipment according to claim 1, wherein 3. Two rotors and two rotors provided on the same rotation axis.
Stator and induction motor with fire pump or smoke exhaust
The induction motor of the fire extinguishing system that drives the fan is used for emergency
Emergency power generation in disaster prevention facilities connected to power generation equipment
Power feeding from the device to the stator windings of the two stators by first connecting the two three-phase stator windings in parallel in a star connection, and Connecting a resistor in parallel to each phase of the two three-phase stator windings in the first connection; and, thirdly, connecting a resistor in series to each phase of one of the three-phase stator windings and delta connection To supply power to only one of the three-phase stator windings
The steps, the steps of the third connection in a three-phase to each phase of the stator winding with the exception take resistor connected in series feeding the fourth, respectively fifth to two three-phase stator windings Starting the induction motor for disaster prevention equipment, comprising the steps of: connecting in parallel with a delta connection to supply power. Before wherein the first feeding process, one solid either
Equipped with the process of connecting the stator winding to the star connection and supplying power
4. The disaster prevention equipment according to claim 3, wherein
How to start an induction motor.