JP6473200B1 - Rotating electromechanical cooling system - Google Patents

Abstract

A rotating electrical machine is efficiently cooled.
A cooling system for a rotating electrical machine is provided in the rotating electrical machine and cools the air in the rotating electrical machine by exchanging heat with the air in the rotating electrical machine, and is cooled by the cooling device. A blower that circulates air in the rotary electric machine, a sensor that measures information used to estimate the internal temperature of the rotary electric machine, and at least one of a cooling device and a blower based on the information measured by the sensor A control device for controlling.
[Selection] Figure 1

Description

  Embodiments of the present invention relate to a cooling system for a rotating electrical machine.

  In a rotating electric machine such as an electric motor used in an electric propulsion system of a ship, a coil generates heat when a current flows through the coils constituting the rotor and the stator. The overheating of the coil causes a deterioration of the insulation of the coil. Therefore, in a rotary electric machine having a large rated capacity, the rotor and the stator of the rotary electric machine are cooled by blowing air into the rotary electric machine. There are self-cooling and other cooling methods. The self-cooling system is a system that cools the outer casing of the rotating electrical machine with a fan on the rotating shaft provided inside, or cools the interior of the rotating electric machine by taking cooling air into the rotating electric machine. . In the other cooling method, the outer casing of the rotating electrical machine is cooled using a cooling fan or the like provided outside the rotating electric machine, and the internal air of the rotating electric machine is cooled by an air cooler via an external heat medium. Alternatively, it is a system that takes in cooling air and cools the inside of the rotating electric machine. Due to the need for cooling during low-speed rotation of rotating electrical machines, other cooling methods are often employed.

JP 60-79261 A

  However, the rotor and stator constituting the rotary electric machine have a complicated structure. For this reason, the blown air cannot be directly applied to the coils constituting the rotor and the stator, and it has been difficult to efficiently cool the rotary electric machine.

  This invention is made | formed under the above-mentioned situation, and makes it a subject to cool a rotary electric machine efficiently.

In order to solve the above problems, a cooling system for a rotating electrical machine according to the present embodiment is provided in the rotating electrical machine, and cools the air in the rotating electrical machine by exchanging heat with the air in the rotating electrical machine. An air blower that circulates the air cooled by the cooling device in the rotating electrical machine, a plurality of sensors that measure information used to estimate the internal temperature of the rotating electrical machine, and the validity of the sensor information obtained from the plurality of sensors Based on the sensor information having the highest priority set in advance among the sensor information determined to be appropriate by the validity determination unit and the validity determination unit , at least one of the cooling device and the blower And a control device for controlling one of them.

It is a block diagram of the cooling system which concerns on 1st Embodiment. It is a block diagram of the cooling device which concerns on 1st Embodiment. It is a block diagram of the air blower which concerns on 1st Embodiment. It is a block diagram of the control apparatus which concerns on 1st Embodiment. It is a figure for demonstrating the control apparatus which concerns on 1st Embodiment. It is a figure for demonstrating the control apparatus which concerns on 2nd Embodiment. It is a block diagram of the control apparatus which concerns on 2nd Embodiment.

<< First Embodiment >>
The cooling system of this embodiment is a system that cools a rotating electric machine. A rotating electrical machine is an electrical machine that converts mechanical energy into electrical energy and electrical energy into mechanical energy, and has a rotating part. For example, an electric motor of a synchronous motor system that generates a predetermined torque from supplied electric power, an electric generator of a power generation system that rotates by wind power, hydraulic power, or the like. Here, a case where the synchronous motor is cooled will be described. Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a configuration diagram of a cooling system 100 for a rotating electrical machine according to a first embodiment.

  As shown in FIG. 1, the synchronous motor 10 to be cooled includes a stator 11, a rotor 12, a rotor bearing portion 14, and a heat pipe 15.

  On the inner peripheral surface of the stator 11, stator coils U <b> 1, V <b> 1, W <b> 1 (not shown) arranged at equal intervals around the rotor 12 are attached. The stator coils U1, V1, W1 are star-connected. The stator coils U1, V1, and W1 are applied with AC voltages having phases different from each other by 120 degrees from an inverter device (not shown). A rotating magnetic field is generated inside the stator 11 by applying voltages having a phase difference of 120 degrees to the stator coils U1, V1, and W1.

The current I flowing through the stator coils U1, V1, W1 attached to the stator 11 is supplied to the synchronous motor 10 from an inverter device (not shown). This current I increases as the load of the synchronous motor 10 increases. Then, heat (I ² R) corresponding to the flowing current I is generated by the winding resistance R of the stator coils U1, V1, and W1. Therefore, the temperature of the stator 11 increases as the current I flowing through the stator coils U1, V1, W1 increases. The heat pipe 15 radiates heat accumulated in the stator 11 to the outside of the stator 11. The heat pipe 15 is made of a material having high thermal conductivity. Due to heat radiation from the stator 11 and the heat pipe 15, the temperature of the air in the synchronous motor 10 rises.

  The rotor 12 rotates by electromagnetic interaction with a rotating magnetic field generated inside the stator 11. The rotor bearing portion 14 holds the rotor 12.

  As shown in FIG. 1, the cooling system 100 includes a cooling device 20, a blower device 30, a sensor 40, and a control device 50. The cooling device 20 cools the air in the synchronous motor 10. The configuration of the cooling device 20 is shown in FIG. The cooling device 20 constitutes a refrigeration cycle in which a refrigerant is circulated through a compressor, a condenser, an expansion valve, and an evaporator. The refrigerant in the cooling device 20 is compressed to a high temperature and a high pressure by a compressor. The refrigerant having reached a high temperature is radiated by the condenser and the temperature is lowered. The refrigerant whose temperature has decreased becomes low temperature and low pressure when it expands through the expansion valve. When this low-temperature refrigerant passes through the evaporator, it exchanges heat with the high-temperature air in the synchronous motor 10 and the temperature rises. Thereby, the air in the synchronous motor 10 is cooled. The refrigerant whose temperature has risen is compressed to a high temperature and a high pressure by a compressor. The cooling device 20 repeats the above-described refrigeration cycle. The condenser is installed outside the synchronous motor 10 and releases heat to the outside of the synchronous motor 10. The temperature control of the cooling device 20 will be described later.

  The blower 30 circulates the air cooled by the cooling device 20 in the synchronous motor 10. The configuration of the blower 30 is shown in FIG. As shown in FIG. 3, the blower 30 includes an inverter 31, an electric motor 32, and a cooling fan 33.

  The inverter 31 receives DC power from a storage battery (not shown), converts it into three-phase AC power, and supplies it to the motor 32. The electric motor 32 rotates in synchronization with the frequency of the supplied AC power. The cooling fan 33 rotates according to the rotation of the electric motor 32. As the number of rotations increases, the amount of air blown increases. That is, the higher the frequency of the AC power supplied from the inverter 31, the greater the amount of air blown by the cooling fan 33. The frequency of the AC power output from the inverter 31 is determined based on the control of the control device 50, details of which will be described later.

  Returning to FIG. 1, the sensor 40 measures the AC power supplied to the synchronous motor 10 and supplies the measured information to the control device 50. The sensor 40 is a power sensor.

  The control device 50 controls the cooling device 20 and the blower device 30 based on the AC power supplied to the synchronous motor 10 measured by the sensor 40. Specifically, the control device 50 controls the cooling temperature by the cooling device 20 and the rotational speed of the cooling fan 33 of the blower device 30. The configuration of the control device 50 is shown in FIG. As shown in FIG. 4, the control device 50 includes an acquisition unit 51, a rotation speed calculation unit 52, a control signal creation unit 53, and a cooling parameter calculation unit 54.

  The acquisition unit 51 acquires sensor information from the sensor 40. Here, the acquisition part 51 acquires the electric power supplied to the synchronous motor 10 as sensor information.

  The rotation speed calculation unit 52 calculates the rotation speed of the cooling fan 33 based on the acquired sensor information (power supplied to the synchronous motor 10). As the output torque of the synchronous motor 10 increases, the AC power supplied to the synchronous motor 10 increases and the amount of heat generated in the synchronous motor 10 increases. In order to maintain the temperature in the synchronous motor 10 at a predetermined temperature, it is necessary to increase the amount of air blown according to the amount of heat generated. The amount of blown air corresponds to the number of rotations of the cooling fan 33. The rotation speed calculation unit 52 uses the graph or table in which the power supplied to the synchronous motor 10 and the rotation speed of the cooling fan are associated with each other as shown in FIG. 5 to obtain the power supplied to the synchronous motor 10. From this, the rotational speed of the cooling fan 33 to be set is obtained.

  The control signal creation unit 53 creates a control signal for controlling the inverter 31. Specifically, a control signal for controlling the inverter 31 is created so that the inverter 31 outputs AC power having a frequency corresponding to the rotation number of the cooling fan 33 obtained by the rotation number calculation unit 52. This is because the rotational speed of the cooling fan 33 is synchronized with the frequency of the three-phase AC power output from the inverter 31.

  The cooling parameter calculation unit 54 calculates the cooling parameters of the cooling device 20 based on the acquired sensor information (electric power supplied to the synchronous motor 10). The cooling parameter is a parameter that determines the opening degree of the expansion valve of the cooling device 20, the circulation speed of the refrigerant, and the like. As the opening degree of the expansion valve is narrowed, the temperature of the refrigerant greatly decreases when the refrigerant passes through the expansion valve and expands. In addition, the cooling effect can be enhanced as the refrigerant circulation speed is increased. The value of the cooling parameter corresponding to the electric power supplied to the synchronous motor 10 is obtained in advance by simulation or the like and stored in the storage unit. More specifically, the value of the cooling parameter necessary for maintaining the temperature of the stator coil in the stator 11 at a predetermined temperature is obtained by simulation corresponding to the power supplied to the synchronous motor 10, and a table is created. And store it in the storage unit. The cooling parameter calculation unit 54 obtains a cooling parameter by table lookup based on the acquired power supplied to the synchronous motor 10. The control signal creation unit 53 creates a control signal corresponding to the obtained cooling parameter and supplies it to the cooling device 20.

  Next, the operation of the cooling system 100 having the above configuration will be described. The sensor 40 measures the power supplied to the synchronous motor 10 and notifies the control device 50 of the power. The cooling parameter calculation unit 54 of the control device 50 calculates a cooling parameter corresponding to the power supplied to the synchronous motor 10, and the control signal creation unit 53 outputs a control signal so that the cooling device 20 operates with the cooling parameter. create. The cooling device 20 operates based on the cooling parameter and cools the warmed air in the synchronous motor 10.

  Further, the rotational speed calculation unit 52 of the control device 50 calculates the rotational speed of the cooling fan 33 according to the electric power supplied to the synchronous motor 10, and the control signal creation unit 53 rotates the cooling fan 33 at the rotational speed. Thus, a control signal for the inverter 31 is created. The blower device 30 rotates the cooling fan 33 based on the control of the control device 50 to circulate the air cooled by the cooling device 20 in the synchronous motor 10. The cooling system 100 continues the above operation.

  By circulating the cooled air in the synchronous motor 10, it is possible to prevent the high-temperature air from staying in the synchronous motor 10, and it is possible to cool a portion that is not directly blown by the blower 30. . For example, since the cooled air enters the stator 11, the stator coil wound around the stator 11 can be cooled. Further, by cooling the heat pipe 15 provided in the stator 11 with cooled air, the inside of the stator 11 can be cooled more effectively.

  As described above, the cooling system 100 for the rotary electric machine according to the present embodiment includes the cooling device 20 that cools the air in the synchronous motor 10 by exchanging heat with the air in the synchronous motor 10 (rotary electric machine). The air blower 30 that circulates the air cooled by the cooling device 20 in the synchronous motor 10 (rotary electric machine), the sensor 40 that measures the power supplied to the synchronous motor 10 (rotary electric machine), and the sensor 40 are And a control device 50 that controls the cooling device 20 and the blower device 30 based on the measured information. Thereby, the coil which was cooled and wound by the rotor and the stator with air can be cooled.

  In addition, the cooling system 100 for the rotating electrical machine according to the present embodiment includes the cooling parameters of the cooling device 20 and the blower so that the temperature of the coils wound around the stator 11 and the rotor 12 becomes a predetermined temperature based on the sensor information. To control the airflow. Thereby, the cooling system 100 can prevent waste of electric power caused by cooling more than necessary, and can efficiently cool the synchronous motor 10.

  Further, the interior of the synchronous motor 10 has a complicated configuration, and it is difficult to directly measure the temperature inside the stator 11 where the temperature rises most with a temperature sensor. If the temperature inside the stator 11 is estimated from the temperature around the stator 11, an estimation error may increase. By estimating the amount of heat generated in the stator 11 from the amount of AC power supplied to the synchronous motor 10, the temperature inside the stator 11 can be estimated more accurately. The control device 50 controls the cooling device 20 and the blower device 30 based on the estimated temperature. Thereby, the cooling system 100 can cool efficiently so that the temperature in the synchronous motor 10 may become an appropriate temperature.

  In the above description, the cooling device 20 using the refrigeration cycle has been described. However, the configuration of the cooling device 20 need not be limited to this. For example, the cooling device 20 can be configured using water, seawater, or the like. Specifically, a pipe for flowing the liquid and a pump for flowing the liquid are provided in the synchronous motor 10. For example, cold water is supplied to the pipe from the outside. When applied to a ship, seawater may be supplied. The cold water supplied from the outside circulates through the piping by a pump and exchanges heat with the hot air in the synchronous motor 10 to cool the air in the synchronous motor 10. The water whose temperature has risen is discharged to the outside, and new cold water is supplied. This piping is formed so that the contact area with the air in the synchronous motor 10 is widened. This is to facilitate heat exchange with the air in the synchronous motor 10.

  Further, in the above description, the air in the synchronous motor 10 is cooled by the evaporator of the cooling device 20, but the cooling method by the cooling device 20 is not necessarily limited to this. For example, an evaporator pipe may be passed through the heat pipe 15 so that heat can be exchanged with the heat pipe 15 in the stator 11.

  In order to circulate the air cooled by the cooling device 20 in the synchronous motor 10, the cooling fans 33 of the blower device 30 may be provided at a plurality of locations. Moreover, the electric motor 32 does not need to be limited to a synchronous motor, What is necessary is just an electric motor which can control the ventilation volume by the cooling fan 33. FIG.

  In the above description, the control device 50 has been described to control both the cooling device 20 and the blower device 30, but only one of them may be controlled. For example, it is possible to fix only the cooling device 20 while fixing the blowing amount of the blowing device 30.

  In the above description, the relationship between the supplied power and the rotation speed of the cooling fan 33 has been described as a simple increase function shown in FIG. 5 for easy understanding. However, the supplied power and the temperature in the motor 10 are complicated functions because there is heat radiation to the outside of the synchronous motor 10. Therefore, a function that defines the relationship between the supplied power and the required number of rotations of the cooling fan 33 may be obtained by experiment or simulation.

  In the above description, the case where the sensor 40 is a power sensor that measures AC power supplied to the synchronous motor 10 has been described. However, the sensor 40 need not be limited to a power sensor. For example, the sensor 40 may be a torque sensor that measures the output torque of the synchronous motor 10. Specifically, the sensor 40 may be a non-contact torque sensor using a magnetostrictive effect, or a contact torque sensor using a spring or the like.

  In the above description, the case where the rotary electric machine is the synchronous motor 10 has been described. However, when the rotary electric machine is a generator, the sensor 40 is a power sensor that measures the generated power. And the control apparatus 50 produces the control signal which controls the cooling device 20 and the air blower 30 based on the measured electric power. When the rotating electrical machine is a generator, the sensor 40 may be a sensor that measures the number of rotations of the generator. This is because the number of revolutions of the generator correlates with the amount of heat generated by the generator.

<< Second Embodiment >>
Next, a second embodiment will be described based on the drawings. About the structure which is the same as that of 1st Embodiment, or equivalent, while using an equivalent code | symbol, the description is abbreviate | omitted or simplified.

  The cooling system 100 for the rotating electrical machine according to the second embodiment determines the validity of the acquired sensor information, and based on the sensor information having the highest priority among the sensor information determined to be appropriate, The point which controls the air blower 30 differs from 1st Embodiment. Here, as shown in FIG. 6, the cooling system 100 measures the sensor 40 a that measures the power supplied to the synchronous motor 10, the sensor 40 b that measures the temperature near the stator 11, and the temperature near the rotor bearing portion. A case where three temperature sensors of the sensor 40c are provided will be described.

  FIG. 7 is a configuration diagram of the control device 50 according to the second embodiment. As illustrated in FIG. 7, the control device 50 according to the second embodiment includes a validity determination unit 55. The validity determination unit 55 determines the validity of a plurality (here, three) of sensor information acquired by the acquisition unit 51. Specifically, as shown in FIG. 6, a table in which an appropriate range of sensor information is set for each sensor is stored in the storage unit in advance. The validity determination unit 55 determines the validity of each of the sensor information by comparing the sensor information acquired by the acquisition unit 51 with this appropriate range.

  The appropriate range of sensor information is set in advance from design values or experimental values. Further, the appropriate range of the sensor information may be changed according to the environmental temperature and the load weight of the synchronous motor 10. Specifically, a plurality of appropriate ranges corresponding to the environmental temperature and the load weight of the synchronous motor 10 are stored in the storage unit, and the validity determination unit 55 is configured to acquire the environmental temperature and the load of the synchronous motor 10 separately acquired. Use the weight of the parameter as a parameter to select a reasonable range of values to use.

  The validity determination unit 55 notifies the acquisition unit 51 of the sensor information having the highest priority among the sensor information determined to be appropriate. For example, in the example illustrated in FIG. 6, the validity determination unit 55 determines that the sensor information of the sensor 40a is not within the valid range. The sensor information of the sensor 40b has the highest priority among the sensor information determined to be appropriate. Therefore, the validity determination unit 55 notifies the acquisition unit 51 that the sensor information having the highest priority among the sensor information determined to be appropriate is the sensor information of the sensor 40b.

  The acquisition unit 51 supplies the sensor information of the sensor 40 b notified from the validity determination unit 55 to the rotation speed calculation unit 52 and the cooling parameter calculation unit 54. The rotation speed calculator 52, the control signal generator 53, and the cooling parameter calculator 54 are the same as those in the first embodiment.

  When the validity determination unit 55 determines that all of the acquired sensor information is not valid, the validity determination unit 55 notifies the control signal creation unit 53 to that effect. Receiving this notification, the control signal creation unit 53 creates control signals for the cooling device 20 and the blower 30 assuming that the synchronous motor 10 is at the maximum output.

  As described above, the rotating electrical machine cooling system 100 according to the second embodiment includes the validity determination unit 55 that determines the validity of the acquired sensor information, and the validity determination unit 55 is appropriate. Based on the sensor information having the highest priority set in advance in the determined sensor information, at least one of the cooling device 20 and the blower device 30 is controlled. Thereby, the cooling system 100 can continue to cool the synchronous motor 10 in a safe state even when any of the sensors 40a to 40c fails.

  Moreover, the control apparatus 50 which concerns on 2nd Embodiment assumes that the output of the synchronous motor 10 is a maximum output, when it is judged that all the acquired sensor information is not appropriate, and cooling device 20 and ventilation The device 30 is controlled. That is, the control device 50 assumes that the heat generation amount of the synchronous motor 10 is the maximum, and controls the cooling device 20 and the blower device 30 so as to exhibit a cooling effect that can cope with the heat generation amount. Thereby, even if all the sensors 40 of the cooling system 100 fail, the synchronous motor 10 can continue to operate in a safe state.

  In the description of the second embodiment, when it is determined that all of the acquired sensor information is not valid, the control device 50 outputs a control signal that can be handled when the synchronous motor 10 is at the maximum output time. Did. However, when it is determined that all of the acquired sensor information is not valid, the synchronous motor 10, the cooling device 20, and the blower device 30 may be stopped.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 10 ... Electric motor 11 ... Stator 12 ... Rotor 14 ... Rotor bearing part 15 ... Heat pipe 20 ... Cooling device 30 ... Air blower 31 ... Inverter 32 ... Electric motor 33 ... Cooling fan 40 ... Sensor 50 ... Control device 51 ... Acquisition part 52 ... Rotation Number calculation unit 53 ... Control signal creation unit 54 ... Cooling parameter calculation unit 55 ... Validity determination unit 100 ... Cooling system

Claims (8)

A cooling device that is provided in the rotating electrical machine and cools the air in the rotating electrical machine by exchanging heat with the air in the rotating electrical machine;
A blower for circulating the air cooled by the cooling device in the rotary electric machine;
A plurality of sensors for measuring information used to estimate the internal temperature of the rotating electrical machine;
A validity determination unit for determining the validity of sensor information acquired from a plurality of the sensors;
A control device that controls at least one of the cooling device and the blower device based on sensor information having the highest priority set in advance among the sensor information that the validity determination unit determines to be appropriate ,
A rotating electrical machine cooling system comprising: When the validity determination unit determines that all of the sensor information acquired from the plurality of sensors is not valid, the control device assumes that the output of the rotating electrical machine is a maximum output and performs the cooling. Controlling the device and the blower,
The cooling system for a rotating electric machine according to claim 1. The cooling device constitutes a refrigeration cycle in which a refrigerant is circulated through a compressor, a condenser, an expansion valve, and an evaporator,
The air in the rotating electrical machine is cooled by exchanging heat with the refrigerant cooled by the refrigeration cycle.
The cooling system for a rotating electric machine according to claim 1 or 2 . The blower is
A cooling fan that blows air cooled by the cooling device;
An electric motor for driving the cooling fan;
An inverter for supplying AC power to the electric motor;
Comprising
The cooling system for a rotating electric machine according to any one of claims 1 to 3 . The rotating electrical machine is an electric motor;
The sensor is a power sensor that measures power supplied to the rotating electrical machine.
The cooling system for a rotating electric machine according to any one of claims 1 to 4 . The rotating electrical machine is an electric motor;
The sensor is a torque sensor that measures an output torque of the rotating electrical machine.
The cooling system for a rotating electric machine according to any one of claims 1 to 4 . The rotating electrical machine is a generator;
The sensor is a power sensor that measures output power of the rotating electrical machine.
The cooling system for a rotating electric machine according to any one of claims 1 to 4 . The control device, when controlling the blower, controls the frequency of AC power output by the inverter based on sensor information acquired from the sensor,
The inverter supplies AC power having a frequency based on control by the control device to an electric motor that drives the cooling fan,
The electric motor that drives the cooling fan rotates the cooling fan at a speed according to the frequency of the supplied AC power.
The cooling system for a rotating electric machine according to claim 4 .

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