Motor heating and dehumidifying device for electric actuator

Abstract

The application relates to a motor heating and dehumidifying device of an electric actuator, and relates to the technical field of motor equipment; the device comprises a PTC heater embedded in a stator silicon steel sheet, and a temperature control circuit electrically connected with the PTC heater, which is used for controlling the PTC heater to be in a heating state or stop heating. The application has the effect of improving the dehumidifying capacity of the motor of the electric actuator.

Description

Technical Field

[0001] This application relates to the technical field of motor equipment, and in particular to a motor heating and dehumidification device for an electric actuator. Background Technology

[0002] The combination of electric actuators and valves plays a vital role in modern industry, widely applied in various fluid transport and control scenarios. With the continuous improvement of industrial automation, this combination is crucial in pipelines, culverts, tunnels, and underground operations, ensuring the stable operation of various processes and significantly improving production efficiency and quality. Its widespread adoption in industrial systems has also driven technological progress and development in related industries.

[0003] In the past, various measures have been taken to address the challenges of using electric actuators and valves in humid environments. Common practices include upgrading the protection level of the electric actuator to improve its sealing performance and minimize the entry of humid external air into the internal cavity. Additionally, improved ventilation promotes air circulation within the cavity and reduces humidity. Some systems also place desiccants inside the cavity, utilizing their moisture-absorbing properties to maintain internal dryness. These methods have mitigated the impact of humid environments on equipment to some extent.

[0004] However, even if the electric actuator meets high protection standards, the internal humidity can still increase if it is exposed to a humid environment for a long time. In addition, the dark and low-temperature working environment easily leads to condensation. Condensation can seriously affect the performance of internal electrical control devices, especially the motor, causing problems such as rusting of silicon steel sheets, altering the motor's magnetic field distribution, and even voltage breakdown of the air gap. Utility Model Content

[0005] In order to improve the dehumidification capability of the motor of an electric actuator, this application provides a motor heating and dehumidification device for an electric actuator.

[0006] The electric actuator motor heating and dehumidification device provided in this application adopts the following technical solution: A motor heating and dehumidification device for an electric actuator includes a PTC heater embedded in the stator and a temperature control circuit electrically connected to the PTC heater, the temperature control circuit being used to control the PTC heater to be in a heating state or to stop heating.

[0007] By adopting the above technical solution, the stator is directly heated by a PTC heater embedded within the stator, effectively removing condensation inside the motor and preventing insulation degradation or short circuit risks caused by moisture. The temperature control circuit can automatically adjust the on / off state of the PTC heater according to the motor's operating status and ambient temperature, improving energy efficiency and preventing overheating damage.

[0008] Preferably, there are multiple PTC heaters, and the axes of the multiple PTC heaters are parallel to the axis of the stator and are evenly distributed along the circumference of the stator.

[0009] By adopting the above technical solution, multiple PTC heaters are evenly distributed along the stator circumference to ensure uniform heating, avoid local overheating or insufficient heating, and improve the dehumidification effect.

[0010] Preferably, the Curie temperature of the PTC heater is selected according to the insulation class of the motor.

[0011] By adopting the above technical solution, it is possible to ensure that the heating temperature does not exceed the heat resistance limit of the insulating material, thereby improving safety and reliability.

[0012] Preferably, the temperature control circuit includes a power supply module, a controller, a relay, a temperature sensor, and an AC power supply. The power supply module includes a transformer. Pin 1 of the controller is electrically connected to terminal A1 of the relay, and terminal A2 of the relay is electrically connected to pin 2 of the controller. Pin 3 of the controller is electrically connected to pin 4 of the controller via the temperature sensor. The voltage output terminal AC+ of the AC power supply is electrically connected to pin 2 of the transformer via the first normally closed contact of the relay, and the voltage output terminal AC- of the AC power supply is electrically connected to pin 3 of the transformer via the second normally closed contact of the relay. Pin 4 of the transformer is electrically connected to one end of a plurality of PTC heaters, and the other end of the plurality of PTC heaters is electrically connected to pin 3 of the transformer.

[0013] By adopting the above technical solution, the real-time temperature of the stator is collected by a temperature sensor, and the heating range is set by a controller. When the real-time temperature of the stator does not reach the heating range, the relay is not triggered, and the PTC heater starts heating. When the real-time temperature of the stator exceeds the heating range, the relay is triggered, and the PTC heater stops heating.

[0014] Preferably, the temperature control circuit further includes an overheat protection relay, one end of which is electrically connected to the end of the multiple PTC heaters furthest from the power supply module, and the other end of which is electrically connected to pin 3 of the transformer through the normally closed contact of the overheat protection relay F1.

[0015] By adopting the above technical solution, the electric overheat protection relay automatically cuts off the circuit when the current is abnormal (such as short circuit or PTC fault), preventing overcurrent damage to the equipment.

[0016] Preferably, the temperature control circuit further includes a temperature control switch, one end of which is electrically connected to the end of the plurality of PTC heaters away from the power supply module, and the other end of which is electrically connected to pin 3 of the transformer.

[0017] By adopting the above technical solution, the temperature control switch serves as redundant protection. When the temperature exceeds the second heating threshold, the circuit is forcibly disconnected to prevent temperature runaway.

[0018] Preferably, the power supply module further includes a rectifier, with pin 4 of the transformer electrically connected to the first input terminal of the rectifier and pin 3 of the transformer electrically connected to the second input terminal of the rectifier; the output terminal of the rectifier is electrically connected to the ground terminal of the rectifier V1 through multiple PTC heaters.

[0019] By adopting the above technical solution, the rectifier can convert AC power into DC power, which is compatible with PTC heaters that require DC power supply, thus expanding the applicability of the device.

[0020] In summary, this application includes at least one of the following beneficial technical effects: 1. Through the coordinated operation of the PTC heater and temperature control circuit, precise heating and dehumidification of the stator are achieved. The controller automatically adjusts the heating state according to preset thresholds to ensure that the motor always operates within a suitable temperature range, effectively preventing condensation. 2. At the same time, the self-limiting temperature characteristic of the PTC heater, combined with the electric overheat protection relay and temperature control switch, greatly improves the reliability and safety of the system, avoiding insulation aging or equipment damage caused by temperature runaway. Attached Figure Description

[0021] Figure 1 This is a cross-sectional view of an embodiment of this application; Figure 2 This is a cross-sectional view of an embodiment of this application; Figure 3 This is a circuit diagram of an embodiment of this application; Figure 4 This is another circuit diagram of an embodiment of this application.

[0022] Reference numerals: 1. Motor; 11. Stator; 2. Heater. Detailed Implementation

[0023] The following combination Figures 1-4 This application will be described in further detail.

[0024] This application discloses a motor heating and dehumidification device for an electric actuator.

[0025] Reference Figure 1 and Figure 2A motor heating and dehumidification device for an electric actuator includes a PTC heater 2 embedded in a silicon steel sheet of a stator 11, and a temperature control circuit electrically connected to the PTC heater 2. The PTC heater 2 is used to heat and dehumidify the stator 11 of the motor 1. The temperature control circuit can control the PTC heater 2 to be in a heating state or to stop heating based on the temperature of the stator 11, thereby effectively removing condensation inside the motor 1 and preventing condensation from affecting the working performance of the motor 1.

[0026] Specifically, the PTC heater 2 uses a PTC heater as the heating substrate material. In this embodiment, the PTC heater 2 is generally cylindrical, and the axes of multiple PTC heaters 2 are parallel to the axis of the stator 11. Multiple PTC heaters 2 are embedded in the silicon steel sheets of the stator 11, and are evenly distributed along the circumference of the stator 11 to ensure heating uniformity. The number of PTC heaters 2 can be increased or decreased according to the heating temperature and heating time requirements, combined with the structure of the motor 1 winding.

[0027] The PTC heater 2 has an autonomous temperature limiting function, and its Curie temperature can be adjusted according to the insulation class of the motor 1. For example, a motor 1 with F-class insulation can use a PTC heater 2 with a Curie temperature of 135 degrees Celsius, while a motor 1 with H-class insulation can use a PTC heater 2 with a Curie temperature of 155 degrees Celsius. This setting effectively prevents heating runaway from causing the temperature to exceed the heat resistance class of the insulation material. When selecting the PTC heater 2, in addition to matching the Curie temperature to the insulation class of the motor 1, its thermal conductivity should also be good to better transfer heat to the stator 11. Alternatively, other thermistor materials with similar autonomous temperature limiting functions can be used as the heating substrate. When the PTC heater 2 is embedded in the silicon steel sheet of the stator 11, it should fit tightly to improve heat transfer efficiency, and the embedding process should be ensured not to damage the silicon steel sheet and the windings of the stator 11.

[0028] The temperature control circuit includes a power supply module, a controller, an AC power supply, a relay K1, a temperature sensor, an overheat protection relay F1, and a temperature control switch S1. The power supply module includes a transformer T1. Pin 1 of the controller is electrically connected to terminal A1 of relay K1, and terminal A2 of relay K1 is electrically connected to pin 2 of the controller. Pin 3 of the controller is electrically connected to pin 4 of the controller via the temperature sensor. The voltage output terminal AC+ of the AC power supply is electrically connected to pin 2 of transformer T1 via the first normally closed contact K11 of relay K1, and the voltage output terminal AC- of the AC power supply is electrically connected to pin 3 of transformer T1 via the second normally closed contact K12 of relay K1. Pin 4 of transformer T1 is electrically connected to one end of multiple PTC heaters 2, and the other end of multiple PTC heaters 2 is electrically connected to one end of the overheat protection relay F1. The other end of the overheat protection relay F1 is connected to pin 3 of transformer T1 via its normally closed contact F11 and the temperature control switch S1.

[0029] The temperature sensor is used to collect the real-time temperature of the stator 11 and convert the collected temperature data into an electrical signal to feed back to the controller. In this embodiment, a PT100 temperature sensor is used. The PT100 temperature sensor has high accuracy and good stability, and can accurately reflect the actual temperature of the stator 11. Alternatively, other high-precision temperature sensors, such as thermocouple sensors, can be used.

[0030] Transformer T1 is used to convert the input voltage to a voltage range compatible with PTC heater 2, and the controller can set a first heating threshold and a second heating threshold. When the operating temperature of motor 1 is too low, causing the controller to not operate, the controller cannot trigger transformer K1. Instead, the first normally closed contact K11 and the second normally closed contact K12 enable PTC heater 2 to be energized and start the heating process. Alternatively, when the real-time temperature of stator 11 is lower than the first heating threshold, the controller also does not trigger transformer K1. When the real-time temperature of stator 11 is higher than the heating threshold, the controller triggers transformer K1, at which point the first normally closed contact K11 and the second normally closed contact K12 open, de-energizing PTC heater 2 and stopping the heating process.

[0031] The operating current value of the overheat protection relay F1 is matched with the rated operating current of the PTC heater 2. When the rated operating current flowing into the PTC heater 2 exceeds the operating current value, the normally closed contact F11 automatically opens, cutting off the power supply circuit of the PTC heater 2. This can protect the circuit when the current rises abnormally due to short circuit, PTC component failure, or other reasons.

[0032] Temperature control switch S1 is a normally closed temperature switch contact, which prevents uncontrolled heating temperature. When the real-time temperature of stator 11 exceeds the second heating threshold, temperature control switch S1 automatically opens, stopping the PTC heater 2 from heating. The temperature threshold of the temperature control switch matches the upper limit required for dehumidification heating of motor 1. When the temperature exceeds this threshold, temperature control switch S1 opens, stopping heating.

[0033] Or, refer to Figure 4 In some cases, the PTC heater 2 requires DC power, and the power supply module also includes a rectifier V1. Pin 4 of transformer T1 is electrically connected to the first input terminal of rectifier V1, and pin 3 of transformer T1 is electrically connected to the second input terminal of rectifier V1. The output terminal of rectifier V1 is electrically connected to one end of overheat protection relay F1 through multiple PTC heaters 2, and the ground terminal of rectifier V1 is electrically connected to the end of temperature control switch S1 away from the normally closed contact F11.

[0034] The implementation principle of the motor heating and dehumidification device for an electric actuator according to an embodiment of this application is as follows: A PTC heater 2 generates heat to dehumidify the stator 11 of the motor 1, preventing condensation inside the motor 1 and thus ensuring the working performance of the motor 1. The temperature control circuit can monitor the temperature of the stator 11 in real time and control the on / off state of the PTC heater 2 according to a preset first heating threshold and a second heating threshold to prevent overheating or underheating. Simultaneously, the overheat protection relay F1 and the temperature control switch S1 further ensure the safety of the heating process.

[0035] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A motor heating and dehumidification device for an electric actuator, characterized in that: The device includes a PTC heater (2) embedded in the stator (11) and a temperature control circuit electrically connected to the PTC heater (2). The temperature control circuit is used to control the PTC heater (2) to be in a heating state or to stop heating. There are multiple PTC heaters (2), and the axes of the multiple PTC heaters (2) are parallel to the axis of the stator (11) and are evenly distributed along the circumference of the stator (11). The Curie temperature of the PTC heater (2) is selected according to the insulation class of the motor. The temperature control circuit includes a power supply module, a controller, a relay, a temperature sensor, and an AC power supply. The power supply module includes a transformer. Pin 1 of the controller is electrically connected to pin A1 of the relay, and pin A2 of the relay is electrically connected to pin 2 of the controller. Pin 3 of the controller is electrically connected to pin 4 of the controller through the temperature sensor. The voltage output terminal AC+ of the AC power supply is electrically connected to pin 2 of the transformer through the first normally closed contact of the relay, and the voltage output terminal AC- of the AC power supply is electrically connected to pin 3 of the transformer through the second normally closed contact of the relay. Pin 4 of the transformer is electrically connected to one end of a plurality of PTC heaters (2), and the other end of the plurality of PTC heaters (2) is electrically connected to pin 3 of the transformer.

2. The motor heating and dehumidification device for an electric actuator according to claim 1, characterized in that: The temperature control circuit also includes an overheat protection relay. One end of the overheat protection relay F1 is electrically connected to the end of the multiple PTC heaters (2) away from the power supply module. The other end of the overheat protection relay is electrically connected to pin 3 of the transformer through the normally closed contact of the overheat protection relay F1.

3. The motor heating and dehumidification device for an electric actuator according to claim 1, characterized in that: The temperature control circuit also includes a temperature control switch, one end of which is electrically connected to the end of the multiple PTC heaters (2) away from the power supply module, and the other end of which is electrically connected to pin 3 of the transformer.

4. The motor heating and dehumidification device for an electric actuator according to claim 1, characterized in that: The power supply module also includes a rectifier. The 4th pin of the transformer is electrically connected to the first input terminal of the rectifier, and the 3rd pin of the transformer is electrically connected to the second input terminal of the rectifier. The output terminal of the rectifier is electrically connected to the ground terminal of the rectifier V1 through multiple PTC heaters (2).

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