CN117307518A - Variable-frequency speed-regulating cooling fan device and control method - Google Patents

Abstract

The embodiment of the specification provides a variable-frequency speed-regulating cooling fan device and a control method. The device comprises a motor control module and a fan; the motor control module comprises an alternating current/direct current rectifier, an intermediate direct current supporting capacitor, a direct current/alternating current converter, a voltage sensor, a temperature sensor and a motor controller of the fan; the fan motor controller is used for controlling the start and stop of the fan according to the voltage sensing signal and the temperature sensing signal; the fan motor controller is further used for receiving a control signal and controlling the direct current/alternating current converter to output a driving voltage corresponding to a target frequency and/or a target amplitude based on the control signal; the fan comprises a motor and an impeller; the motor drives the impeller to rotate at a target rotation speed based on the received driving voltage. The device can not only ensure that the motor always works under ideal working conditions based on real-time monitoring, but also can realize rotation speed adjustment according to heat dissipation requirements, improve the heat dissipation power of the fan, and adapt to heat dissipation requirements under different conditions.

Description

Variable-frequency speed-regulating cooling fan device and control method

Technical Field

The embodiment of the specification relates to the technical field of motor train unit cooling fans, in particular to a variable-frequency speed-regulating cooling fan device and a control method.

Background

During running of the motor train unit, a cooling device is an indispensable component. For example, traction converters, traction motors, traction transformers, and the like in a motor train unit need to be equipped with corresponding cooling and heat dissipation devices to maintain each system operating within a reasonable temperature interval. Although cooling devices with different modes such as air cooling, water cooling, oil cooling and the like can be designed according to different systems, the cooling fan is a direct acting device for taking away heat, and is generally an essential device in a motor train unit. Therefore, it is necessary to ensure the proper operation of the cooling fan.

In practical applications, however, cooling fans are very prone to failure. Because the heat radiation capacity of the cooling fan is in direct proportion to the rotating speed of the motor, under the condition of fixed highest rotating speed, the size of the fan impeller can only be increased in order to ensure the heat radiation power, and then the motor shaft power is increased, the working temperature rise of the motor is raised, and thus the motor insulation faults such as turn-to-turn breakdown, interphase breakdown, integral overheat burning loss and the like are induced. Therefore, how to reduce motor faults while ensuring the heat dissipation effect of the cooling fan is a problem that needs to be solved currently.

Disclosure of Invention

The embodiment of the specification aims to provide a variable-frequency speed-regulating cooling fan device and a control method, so as to solve the problem of reducing motor faults of a cooling fan while guaranteeing a heat dissipation effect.

In order to solve the technical problems, an embodiment of the present disclosure provides a variable-frequency speed-regulating cooling fan device, including a motor control module and a fan; the motor control module comprises an alternating current/direct current rectifier, an intermediate direct current supporting capacitor, a direct current/alternating current converter, a voltage sensor, a temperature sensor and a motor controller of the fan; the voltage sensor is used for monitoring the voltage of the middle direct current support capacitor and outputting a voltage sensing signal; the temperature sensor is used for monitoring the temperature of the motor and outputting a temperature sensing signal; the fan motor controller is used for controlling the start and stop of the fan according to the voltage sensing signal and the temperature sensing signal; the fan motor controller is further used for receiving a control signal and controlling the direct current/alternating current converter to output a driving voltage corresponding to a target frequency and/or a target amplitude based on the control signal; the fan comprises a motor and an impeller; the motor drives the impeller to rotate at a target rotation speed based on the received driving voltage.

In some embodiments, the motor control module further comprises a current sensor; the current sensor is used for monitoring the current of the motor control module and outputting a current sensing signal.

In some embodiments, the motor control module is configured to drive the fan to operate when the voltage sensing signal and the temperature sensing signal are within a preset voltage range and a preset temperature range, respectively.

In some embodiments, the fan motor controller transmits a driving pulse signal to the dc/ac converter based on the control signal to cause the dc/ac converter to output a driving voltage of a target frequency and/or a target amplitude.

In some embodiments, the apparatus further comprises a three-phase ac contactor; the three-phase alternating current contactor is used for connecting an alternating current power supply and the input end of the motor control module.

Based on the above embodiment, the device further comprises an air switch; the air switch is used for controlling the conduction between an alternating current power supply and the three-phase alternating current contactor.

In some embodiments, the fan is configured to dissipate heat for the target device; the target device includes one of a traction inverter, a traction motor, and a traction transformer.

Based on the above embodiment, the target frequency and/or the target amplitude corresponding to the control signal are determined based on the working state of the target device; the operating state includes at least one of temperature, power, and operating environment.

In some embodiments, the dc/ac converter is in a variable-voltage variable-frequency open-loop control mode; the driving voltage includes a pulse width modulated voltage.

In some embodiments, the variable frequency speed cooling fan device is applied to a motor train unit train; the control signals include signals sent by control modules of the motor train unit train.

The embodiment of the specification also provides a control method of the variable-frequency speed-regulating cooling fan device, wherein an execution main body of the method is a fan motor controller in the variable-frequency speed-regulating cooling fan device; the method comprises the following steps: acquiring a voltage sensing signal of the middle direct current supporting capacitor; the front end and the rear end of the middle direct current supporting capacitor are respectively connected with an alternating current/direct current rectifier and a direct current/alternating current converter; starting a motor in the fan under the condition that the voltage sensing signal is in a preset voltage range; acquiring a temperature sensing signal of the motor; acquiring a control signal under the condition that the temperature sensing signal is in a preset temperature range; and sending a driving pulse signal to a direct current/alternating current converter based on the control signal so that the direct current/alternating current converter outputs driving voltage corresponding to target frequency and/or target amplitude to the motor, and the motor drives the impeller to rotate at target rotating speed.

In some embodiments, the transmitting a driving pulse signal to the dc/ac converter based on the control signal includes: acquiring a current sensing signal of the output current of the direct current/alternating current converter; and under the condition that the current sensing signal is in a preset current range, transmitting a driving pulse signal to the direct current/alternating current converter based on the control signal.

The technical scheme provided by the embodiment of the specification can be seen that the variable-frequency speed-regulating cooling fan device of the embodiment of the specification monitors voltage and temperature respectively through the voltage sensor and the temperature sensor so as to maintain the start of the fan when the voltage and the temperature are normal. Meanwhile, the fan motor controller controls the direct current/alternating current converter to output driving voltage with target frequency and target amplitude according to the control signal, so that the motor drives the impeller to rotate according to the target rotating speed, and the current heat dissipation requirement is met. Through the device, the working state of the fan can be monitored in real time, the motor is guaranteed to work under ideal working conditions all the time, the rotation speed of the cooling fan can be adjusted according to the heat dissipation requirement, the heat dissipation power of the fan is improved, and the device is effectively suitable for heat dissipation requirements under different conditions.

Drawings

In order to more clearly illustrate the embodiments of the present description or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments described in the present description, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic structural diagram of a variable-frequency speed-regulating cooling fan device according to an embodiment of the present disclosure;

fig. 2 is a schematic structural diagram of a motor control module according to an embodiment of the present disclosure;

FIG. 3 is a schematic structural view of a fan according to an embodiment of the present disclosure;

fig. 4 is a schematic flow chart of a control method of a variable-frequency speed-regulating cooling fan device according to an embodiment of the present disclosure.

Reference numerals illustrate: 1. an air switch; 2. a three-phase ac contactor; 3. an ac/dc rectifier; 4. a middle direct current support capacitor; 5. a DC/AC converter; 6. a current sensor; 7. a fan motor controller; 8. a motor; 9. an impeller; a. a voltage sense signal; b. a current sense signal; c. a temperature sensing signal; d. a driving pulse signal; e. a control signal.

Detailed Description

The technical solutions of the embodiments of the present specification will be clearly and completely described below with reference to the drawings in the embodiments of the present specification, and it is apparent that the described embodiments are only some embodiments of the present specification, not all embodiments. All other embodiments, which can be made by one of ordinary skill in the art without undue burden from the present disclosure, are intended to be within the scope of the present disclosure.

In order to solve the technical problems, an embodiment of the present disclosure provides a variable-frequency speed-regulating cooling fan device. As shown in fig. 1, the variable-frequency speed-regulating cooling fan device comprises a motor control module and a fan.

The motor control module is mainly used for outputting corresponding working voltage to the fan so that the motor 8 in the fan drives the impeller 9 to rotate, and heat dissipation and cooling are performed in an air cooling mode. Because the variable-frequency speed-regulating cooling fan device can realize variable-frequency speed regulation, the motor control module can also regulate the output voltage, for example, change the frequency and the amplitude of the output voltage and the like. When the frequency and the amplitude of the voltage are different, the frequency and the rotating speed of the motor 8 based on the rotation of the voltage are also different, so that the heat dissipation power of the fan is adjusted, and the effect of variable-frequency speed regulation is realized.

Specifically, as shown in fig. 2, the motor 9 control module includes an ac/dc rectifier 3, an intermediate dc support capacitor 4, a dc/ac converter 5, a voltage sensor (not shown), a temperature sensor, and a fan motor controller 7.

The ac/dc rectifier 3 is used to rectify an ac voltage into a dc voltage. If the power supply is directly connected to the motor 8, the effect of frequency conversion cannot be achieved by adjusting the voltage, and thus the ac/dc rectifier 3 can be provided. Correspondingly, the input of the motor control module may be arranged on the ac/dc rectifier 3. In particular, the ac/dc rectifier 3 may be a three-phase uncontrolled rectifier, so as to rectify an ac 380V voltage. In practical applications, the specification of the ac/dc rectifier 3 may be adjusted according to the requirements, which is not limited.

The middle direct current supporting capacitor 4 is mainly used for smoothing and filtering the direct current voltage output by the alternating current/direct current rectifier 3, and has the functions of voltage stabilization and filtering. After the ac/dc rectifier 3 receives the input ac voltage and rectifies the ac voltage into a dc voltage, the intermediate dc supporting capacitor 4 filters the rectified voltage to reduce the fluctuation in the dc voltage, and ensure the application effect when the dc voltage is subsequently output to the motor 8.

The dc/ac converter 5 is configured to re-convert the dc voltage output from the intermediate dc support capacitor 4 into an ac voltage, and output the ac voltage to the motor 8 in the fan. In the embodiment of the present disclosure, since the variable frequency speed regulation is required, the dc/ac converter 6 can convert the dc voltage into an ac voltage with a specific amplitude and/or frequency according to the requirement of the control signal e, that is, a driving voltage output to the motor 9. The dc/ac converter 5 may generate a pulse with a certain frequency, width or phase according to the requirement of the control signal e, and amplify the pulse into an output ac voltage according to the characteristics of the pulse.

Specifically, the dc/ac converter 5 is a variable-voltage variable-frequency open-loop control, so as to output PWM voltage with specific frequency and amplitude, and drive the fan motor 8 to rotate at specific rotation speed. The specific specification and the working process of the dc/ac converter 5 may be set according to the actual application requirement, which is not described herein.

The ac/dc rectifier 3, the intermediate dc supporting capacitor 4 and the dc/ac converter 5 constitute a fan motor driver for directly driving the motor 8 in the fan.

The voltage sensors are arranged at two ends of the middle direct current support capacitor 4, so that middle direct current voltage values corresponding to the middle direct current support capacitor 4 are collected in real time, and corresponding voltage sensing signals a are generated. The voltage sensing signal a may be sent to the fan motor controller 7 in real time.

In some embodiments, the device may also include a current sensor 6. The current sensor 6 is installed at the output end of the dc/ac converter 5, and can collect the output current value of the dc/ac converter 5 in real time and generate a corresponding current sensing signal b. The current sensing signal b may be sent to the fan motor controller 7 in real time.

As shown in fig. 3, the blower includes a motor 8 and an impeller 9. The motor 8 is based on the received voltage, wherein the rotor is rotatable under the influence of electromagnetic induction. When the motor 8 is connected with the impeller 9, the motor 8 can drive the impeller 9 to rotate after the motor 8 is electrified. The impeller 9 can blow air in a specific direction when rotating, thereby realizing the air cooling effect.

According to the received voltage, the rotation speed of the motor 8 is differentiated to a certain extent, and when the rotation speed of the motor 8 needs to be controlled, the rotation speed of the motor can be changed by adjusting the frequency or the amplitude of the driving voltage input to the motor 8. Correspondingly, when the rotating speeds of the impellers 9 are different, the generated air cooling effects are different, and the corresponding air cooling control effect can be realized according to the requirements.

The specific specifications of the fan, including the specification of the motor 8 and the shape and size of the impeller 9, can be set and adjusted according to the actual application requirements, and are not described herein.

The fan may be a target device, and in this embodiment, the target device may be a corresponding device on a train of the motor train unit, where heat needs to be dissipated, for example, a traction converter, a traction motor, a traction transformer, and the like. Typically, different devices are individually equipped with air cooling devices. In practical application, other devices can be set as target devices for action according to requirements, and the method is not limited.

A temperature sensor may be provided on the motor 8 to detect the temperature of the motor 8 in real time and generate a corresponding temperature sensing signal c. The temperature sensing signal c may be sent to the fan motor controller 7 in real time.

In some embodiments, the motor 8 of the fan is an asynchronous motor or a permanent magnet motor, and correspondingly, the temperature sensor is installed on the motor stator winding, so that the temperature of the motor stator is measured.

The fan motor controller 7 is a central control module in the motor control module, and is used for monitoring other components and adjusting the working state of the motor 8 and the driving voltage output by the motor control module based on the monitoring result and the heat dissipation requirement.

The fan motor controller 7 can be a corresponding circuit module, and can directly realize signal processing and generation through corresponding circuit logic; or a computing module to which a corresponding computer control program is applied. In practical application, the form of the fan motor controller 7 can be adjusted according to the requirements, and the fan motor controller is not limited.

Specifically, in the case that the fan motor controller 7 can receive at least one of the voltage sensing signal a, the temperature sensing signal c, and the current sensing signal b, the fan motor controller 7 can determine whether the current operating state of the cooling device is normal according to a comparison result between the above sensing signal and a preset determination range.

For example, a preset voltage range, a preset temperature range, and a preset current range are set in the fan motor 9 controller 8 for different signals. The preset voltage range, the preset temperature range and the preset current range are used for respectively limiting the voltage, the temperature and the current of the cooling device in normal operation. When the voltage, temperature or current is not in the corresponding range, the abnormal working state of the cooling device can be identified. The specific preset voltage range, preset temperature range and preset current range can be set by staff based on working experience, and the range can be automatically adjusted in real time according to whether the cooling device has abnormality or not under different working parameter values in actual working, so that the method is not limited.

Specifically, the judgment of the fan motor controller 7 on the voltage sensing signal a can be started before the fan works, and before the fan is communicated, the voltage sensing signal a can be measured at two ends of the middle direct current support capacitor 5 after the motor 9 control module is connected with the alternating current power supply. The fan motor 9 controller 8 may determine whether to control the fan operation based on whether the voltage sensing signal a is within the preset voltage range.

After the communication fan works, the temperature sensor can acquire the temperature of the motor 8 during working, the current sensor 7 can acquire the output current, and the fan motor controller 7 can synthesize the voltage sensing signal a, the temperature sensing signal c and the current sensing signal b to judge whether the current working state of the cooling device is normal or not, so that whether the fan needs to be stopped or not is determined.

In the case where the apparatus operates normally according to the above-described sensing signal determining means, the blower motor controller 7 may receive the control signal e and control the dc/ac converter 6 to output the driving voltage corresponding to the target frequency and/or the target amplitude based on the control signal e.

The control signal e is used for indicating a state parameter of the output driving voltage, and after the fan motor controller 7 receives the control signal e, a driving pulse signal d corresponding to the control signal e can be generated, so that the direct current/alternating current converter 6 outputs the driving voltage with the target frequency and/or the target amplitude.

In some embodiments, the control signal e may be a signal sent by a control module of a motor train unit train. The control module of the motor train unit train acquires the working states of different devices, and combines the current running state to control the power of the cooling device. The operating state may be at least one of temperature, power, operating environment. For example, when a greater temperature rise of the target device is detected, the power of the cooling means may be increased to rotate the impeller 9 at a greater rotational speed, the control signal e being sent out corresponding to a higher frequency and/or amplitude of the driving voltage; when the train is immediately brought into station, in order to avoid the influence of the excessive noise of the cooling device on the passengers, the rotation speed of the fan can be reduced, and the corresponding control signal e is corresponding to a driving voltage with smaller frequency and/or amplitude. In practical application, the control signal e generated by the control module can be set according to specific application requirements, and will not be described in detail herein.

Specifically, the fan motor controller 7 may send a driving pulse signal d to the dc/ac converter 5 based on the control signal e, and the dc/ac converter 5 may amplify the driving pulse signal d according to the level of the driving pulse signal d in combination with the input dc voltage, so as to generate a driving voltage with a corresponding frequency and/or amplitude.

In the case of a pre-controlled frequency and/or amplitude of the drive voltage, the motor 8 can be rotated at a specific rotational speed under the influence of the drive voltage

Accordingly, the voltage output from the dc/ac converter 5 may be a PWM (pulse width modulation) voltage.

The device also comprises a three-phase alternating current contactor 2, as shown in fig. 1, wherein the three-phase alternating current contactor 2 is connected with the input end of the motor control module, and an alternating current power supply outputs voltage to the motor 8 control module based on the three-phase alternating current contactor 2. The three-phase alternating current contactor 2 can effectively control the starting and stopping of the three-phase motor 8, and effectively ensure the operation of the motor 8.

Furthermore, the device may also comprise an air switch 1. The air switch 1 is used for controlling the conduction between an alternating current power supply and the three-phase alternating current contactor 2. The air switch 1 can be automatically disconnected after the current exceeds a certain value, so that a circuit is effectively protected, the motor 8 is prevented from being burnt due to overlarge current under the conditions of short circuit and the like, and the motor 8 is further protected.

Preferably, the variable-frequency speed-regulating cooling fan device is a complete independent module, namely, a fan motor controller 7, an alternating current/direct current rectifier 3, a voltage sensor, an intermediate direct current supporting capacitor 4, a direct current/alternating current converter 5, a current sensor 6 and a fan are integrally designed, so that the device is placed in a motor train unit conveniently and the stability of the device is guaranteed. In practical application, each component in the device can be split into separate modules for installation according to requirements, and the device is not limited in this respect.

Through the description of the embodiment and the scene example, it can be seen that the variable-frequency speed-regulating cooling fan device monitors the voltage and the temperature respectively through the voltage sensor and the temperature sensor, so as to maintain the start of the fan when the voltage and the temperature are normal. Meanwhile, the fan motor controller controls the direct current/alternating current converter to output driving voltage with target frequency and target amplitude according to the control signal, so that the motor drives the impeller to rotate according to the target rotating speed, and the current heat dissipation requirement is met. Through the device, the working state of the fan can be monitored in real time, the motor is guaranteed to work under ideal working conditions all the time, the rotation speed of the cooling fan can be adjusted according to the heat dissipation requirement, the heat dissipation power of the fan is improved, and the device is effectively suitable for heat dissipation requirements under different conditions.

Based on the variable-frequency speed-regulating cooling fan device, the embodiment of the specification also provides a control method of the variable-frequency speed-regulating cooling fan device. The execution main body of the control method of the variable-frequency speed-regulating cooling fan device can be the fan motor controller. As shown in fig. 4, the control of the variable-frequency speed-regulating cooling fan device comprises the following specific implementation steps.

S410: acquiring a voltage sensing signal of the middle direct current supporting capacitor; the front end and the rear end of the middle direct current support capacitor are respectively connected with an alternating current/direct current rectifier and a direct current/alternating current converter.

The middle direct current support capacitor is mainly used for smoothing and filtering direct current voltage output by the alternating current/direct current rectifier, and has the functions of voltage stabilization and filtering. After the alternating current/direct current rectifier receives the input alternating current voltage and rectifies the alternating current voltage into direct current voltage, the intermediate direct current support capacitor filters the rectified voltage, so that fluctuation in the direct current voltage is reduced, and the application effect of the direct current voltage when the direct current voltage is output to the motor is ensured.

The ac/dc rectifier is used to rectify an ac voltage into a dc voltage. If the power supply is directly connected to the motor, the frequency conversion effect cannot be achieved by adjusting the voltage, so that an alternating current/direct current rectifier can be arranged. Accordingly, the input of the motor control module may be provided on the ac/dc rectifier. Specifically, the ac/dc rectifier may be a three-phase uncontrolled rectifier, so as to rectify the ac 380V voltage. In practical application, the specification of the ac/dc rectifier can be adjusted according to the requirement, which is not limited.

The DC/AC converter is used for converting the DC voltage output by the middle DC support capacitor into AC voltage again and outputting the AC voltage to a motor in the fan. In the embodiment of the present disclosure, since variable frequency speed regulation is required, the dc/ac converter may convert a dc voltage into an ac voltage with a specific amplitude and/or frequency according to a requirement of a control signal, that is, a driving voltage output to the motor. The DC/AC converter can generate pulses with certain frequency, width or phase according to the requirements of control signals, and then amplify the pulses into output AC voltage according to the characteristics of the pulses.

The voltage sensors are arranged at two ends of the middle direct current supporting capacitor, so that middle direct current voltage values corresponding to the middle direct current supporting capacitor are collected in real time, and corresponding voltage sensing signals are generated. The voltage sensing signal can be sent to the fan motor controller in real time.

S420: and under the condition that the voltage sensing signal is in a preset voltage range, starting a motor in the fan.

For the voltage sensing signal, a preset voltage range may be set for indicating a voltage magnitude range when the cooling device is operating normally. When the fan does not work, the motor control module is connected with the alternating current power supply, and then the voltage sensing signals can be obtained through measurement at the two ends of the middle direct current support capacitor. The fan motor controller can determine whether to control the fan to work according to whether the voltage sensing signal is in the preset voltage range.

Under the condition that the voltage sensing signal is in a preset voltage range, a motor in the fan can be started to work according to a certain rotating speed. If the voltage sensing signal is not in the preset voltage range, that is, the current voltage is abnormal, the fan motor controller can send a corresponding alarm signal to an administrator or control equipment to inform the current fan of the abnormality. Meanwhile, under the condition that the voltage is always abnormal, the starting of the motor in the fan is avoided.

S430: and acquiring a temperature sensing signal of the motor.

The fan comprises a motor and an impeller. The motor is based on the received voltage, wherein the rotor can rotate under the action of electromagnetic induction. Under the condition that the motor is connected with the impeller, the motor can drive the impeller to rotate after the motor is electrified. The impeller can blow in a specific direction when rotating, so that the air cooling effect is realized.

According to the received voltage, the rotating speeds of the motors are different to a certain extent, and when the rotating speeds of the motors need to be controlled, the rotating speeds of the motors can be changed by adjusting the frequency or the amplitude of the driving voltage of the motors with the input values. Correspondingly, when the rotating speeds of the impellers are different, the generated air cooling effect is also different, and the corresponding air cooling control effect can be realized according to the requirements.

The specific specifications of the fan, including the specification of the motor and the shape and size of the impeller, can be set and adjusted according to the actual application requirements, and are not described herein.

The fan may be a target device, and in this embodiment, the target device may be a corresponding device on a train of the motor train unit, where heat needs to be dissipated, for example, a traction converter, a traction motor, a traction transformer, and the like. Typically, different devices are individually equipped with air cooling devices. In practical application, other devices can be set as target devices for action according to requirements, and the method is not limited.

The temperature sensor can be arranged on the motor to detect the temperature of the motor in real time and generate corresponding temperature sensing signals. The temperature sensing signal can be sent to the fan motor controller in real time.

In some embodiments, the motor of the fan is an asynchronous motor or a permanent magnet motor, and correspondingly, the temperature sensor is arranged on the motor stator winding, so that the temperature of the motor stator is measured.

S440: and under the condition that the temperature sensing signal is in a preset temperature range, acquiring a control signal.

Correspondingly, the temperature sensing signal can also be provided with a preset temperature range to indicate the temperature of the motor during normal operation. After the fan works, the motor has certain temperature rise. If the temperature of the motor is too high or too low, the current working state of the motor is abnormal, and insulation faults are easy to cause especially when the temperature is too high.

Therefore, if the temperature sensing signal is in the preset temperature range, the current motor is in a normal working state, and the control signal can be acquired to perform subsequent frequency conversion operation. If the temperature sensing signal is not in the preset temperature range, the circuit connection with the fan can be disconnected, the work of the motor is stopped, and faults are avoided.

The control signal is used for indicating the state parameter of the output driving voltage, and after the fan motor controller receives the control signal, the fan motor controller can generate a driving pulse signal corresponding to the control signal so that the direct current/alternating current converter outputs the driving voltage with the target frequency and/or the target amplitude.

In some embodiments, the control signal may be a signal sent by a control module of a motor train unit train. The control module of the motor train unit train acquires the working states of different devices, and combines the current running state to control the power of the cooling device. The operating state may be at least one of temperature, power, operating environment. For example, when a large temperature rise of the target device is detected, the power of the cooling device may be increased to rotate the impeller at a larger rotational speed, and the issued control signal is a drive voltage corresponding to a higher frequency and/or amplitude; in order to avoid the influence of excessive noise of the cooling device on passengers when the train is immediately taken into the station, the rotational speed of the fan can be reduced, and the corresponding control signal is a driving voltage corresponding to smaller frequency and/or amplitude. In practical application, the control signal generated by the control module can be set according to specific application requirements, and will not be described in detail herein.

S450: and sending a driving pulse signal to a direct current/alternating current converter based on the control signal so that the direct current/alternating current converter outputs driving voltage corresponding to target frequency and/or target amplitude to the motor, and the motor drives the impeller to rotate at target rotating speed.

The fan motor controller can send a driving pulse signal to the direct current/alternating current converter based on the control signal, and the direct current/alternating current converter can amplify the driving pulse signal according to the level of the driving pulse signal and the input direct current voltage, so that driving voltage with corresponding frequency and/or amplitude can be generated.

Under the condition of the pre-control of the frequency and/or the amplitude of the driving voltage, the motor can rotate according to a specific rotating speed under the action of the driving voltage

Accordingly, the voltage output by the dc/ac converter may be a PWM (pulse width modulation) voltage.

The specific generation process of the driving voltage can be set by combining the working principle of the direct current/alternating current converter, and will not be described herein.

In some embodiments, the device further comprises a current sensor. The current sensor is arranged at the output end of the direct current/alternating current converter, can acquire the output current value of the direct current/alternating current converter in real time, and generates a corresponding current sensing signal b. The current sensing signal b can be sent to the fan motor controller in real time.

Correspondingly, the current sensing signal b also corresponds to a preset current range, and is used for limiting the normal range of the current. When the current sensing signal b is in a preset current range, the fan is maintained to work normally; in contrast, when the current is not within the preset current range, the operation of the blower is stopped.

When the fan is stopped due to the fact that the voltage, the temperature or the current is detected not to be in the preset range, the standby cooling equipment is generally arranged for the target equipment, so that the target equipment can be cooled by air cooling through the standby cooling equipment, and normal operation of the equipment is guaranteed.

The variable-frequency speed-regulating cooling fan device can be applied to the technical field of cooling fans of motor train units, can also be applied to other technical fields except the technical field of cooling fans of motor train units, for example, other technical fields related to cooling and heat dissipation, and is not limited in this regard.

In this specification, each embodiment is described in a progressive manner, and identical and similar parts of each embodiment are all referred to each other, and each embodiment mainly describes differences from other embodiments. In particular, for system embodiments, since they are substantially similar to method embodiments, the description is relatively simple, as relevant to see a section of the description of method embodiments. In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the embodiments of the present specification. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the different embodiments or examples described in this specification and the features of the different embodiments or examples may be combined and combined by those skilled in the art without contradiction.

While the process flows described above include a plurality of operations occurring in a particular order, it should be apparent that the processes may include more or fewer operations, which may be performed sequentially or in parallel (e.g., using a parallel processor or a multi-threaded environment).

Any numerical value recited herein includes all values of the lower and upper values that increment by one unit from the lower value to the upper value, as long as there is a spacing of at least two units between any lower value and any higher value. For example, if it is stated that the number of components or the value of a process variable (e.g., temperature, pressure, time, etc.) is from 1 to 90, preferably from 20 to 80, more preferably from 30 to 70, then the purpose is to explicitly list such values as 15 to 85, 22 to 68, 43 to 51, 30 to 32, etc. in this specification as well. For values less than 1, one unit is suitably considered to be 0.0001, 0.001, 0.01, 0.1. These are merely examples that are intended to be explicitly recited in this description, and all possible combinations of values recited between the lowest value and the highest value are believed to be explicitly stated in the description in a similar manner.

The foregoing is merely exemplary of the present application and is not intended to limit the present application. Various modifications and changes may be made to the present application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc. which are within the spirit and principles of the present application are intended to be included within the scope of the claims of the present application.

All articles and references, including patent applications and publications, disclosed herein are incorporated by reference for all purposes. The term "consisting essentially of …" describing a combination shall include the identified element, ingredient, component or step as well as other elements, ingredients, components or steps that do not substantially affect the essential novel features of the combination. The use of the terms "comprises" or "comprising" to describe combinations of elements, components, or steps herein also contemplates embodiments consisting essentially of such elements, components, or steps. By using the term "may" herein, it is intended that any attribute described as "may" be included is optional.

Multiple elements, components, parts or steps can be provided by a single integrated element, component, part or step. Alternatively, a single integrated element, component, part or step may be divided into separate plural elements, components, parts or steps. The disclosure of "a" or "an" to describe an element, component, section or step is not intended to exclude other elements, components, sections or steps.

It is to be understood that the above description is intended to be illustrative, and not restrictive. Many embodiments and many applications other than the examples provided will be apparent to those of skill in the art upon reading the above description. The disclosures of all articles and references, including patent applications and publications, are incorporated herein by reference for the purpose of completeness.

Claims (12)

1. The variable-frequency speed-regulating cooling fan device is characterized by comprising a motor control module and a fan;

the motor control module comprises an alternating current/direct current rectifier, an intermediate direct current supporting capacitor, a direct current/alternating current converter, a voltage sensor, a temperature sensor and a motor controller of the fan; the voltage sensor is used for monitoring the voltage of the middle direct current support capacitor and outputting a voltage sensing signal; the temperature sensor is used for monitoring the temperature of the motor and outputting a temperature sensing signal; the fan motor controller is used for controlling the start and stop of the fan according to the voltage sensing signal and the temperature sensing signal; the fan motor controller is further used for receiving a control signal and controlling the direct current/alternating current converter to output a driving voltage corresponding to a target frequency and/or a target amplitude based on the control signal;

the fan comprises a motor and an impeller; the motor drives the impeller to rotate at a target rotation speed based on the received driving voltage.

2. The apparatus of claim 1, wherein the motor control module further comprises a current sensor; the current sensor is used for monitoring the current of the motor control module and outputting a current sensing signal.

3. The apparatus of claim 1, wherein the motor control module is configured to drive the blower in operation when the voltage sense signal and the temperature sense signal are within a predetermined voltage range and a predetermined temperature range, respectively.

4. The apparatus of claim 1, wherein the fan motor controller sends a drive pulse signal to a dc/ac converter based on the control signal to cause the dc/ac converter to output a drive voltage at a target frequency and/or a target amplitude.

5. The apparatus of claim 1, further comprising a three-phase ac contactor; the alternating current power supply outputs voltage to the motor control module based on the three-phase alternating current contactor.

6. The apparatus of claim 5, further comprising an air switch; the air switch is used for controlling the conduction between an alternating current power supply and the three-phase alternating current contactor.

7. The apparatus of claim 1, wherein the blower is to dissipate heat for a target device; the target device includes one of a traction inverter, a traction motor, and a traction transformer.

8. The apparatus of claim 7, wherein a target frequency and/or a target amplitude for the control signal is determined based on an operating state of the target device; the operating state includes at least one of temperature, power, and operating environment.

9. The apparatus of claim 1, wherein the dc/ac converter is in a variable voltage variable frequency open loop control mode; the driving voltage includes a pulse width modulated voltage.

10. The device of claim 1, wherein the variable frequency speed cooling fan device is applied to a motor train unit train;

the control signals include signals sent by control modules of the motor train unit train.

11. The control method of the variable-frequency speed-regulating cooling fan device is characterized in that an execution main body of the method is a fan motor controller in the variable-frequency speed-regulating cooling fan device; the method comprises the following steps:

acquiring a voltage sensing signal of the middle direct current supporting capacitor; the front end and the rear end of the middle direct current supporting capacitor are respectively connected with an alternating current/direct current rectifier and a direct current/alternating current converter;

starting a motor in the fan under the condition that the voltage sensing signal is in a preset voltage range;

acquiring a temperature sensing signal of the motor;

acquiring a control signal under the condition that the temperature sensing signal is in a preset temperature range;

and sending a driving pulse signal to a direct current/alternating current converter based on the control signal so that the direct current/alternating current converter outputs driving voltage corresponding to target frequency and/or target amplitude to the motor, and the motor drives the impeller to rotate at target rotating speed.

12. The control method of claim 11, wherein the transmitting a driving pulse signal to the dc/ac converter based on the control signal comprises:

acquiring a current sensing signal of the output current of the direct current/alternating current converter;

and under the condition that the current sensing signal is in a preset current range, transmitting a driving pulse signal to the direct current/alternating current converter based on the control signal.