CN215528897U

CN215528897U - Actuator for valves and fittings

Info

Publication number: CN215528897U
Application number: CN202120918790.7U
Authority: CN
Inventors: K·克里希纳戈达; G·P·宁盖亚; A·A·穆罕默德
Original assignee: Auma Riester GmbH and Co KG
Current assignee: Auma Riester GmbH and Co KG
Priority date: 2021-04-29
Filing date: 2021-04-29
Publication date: 2022-01-14
Anticipated expiration: 2031-04-29

Abstract

The present application relates to an actuator for valves and fittings comprising a three-phase asynchronous motor and a braking unit for braking the three-phase asynchronous motor, wherein the braking unit is configured to modify the configuration of at least one of the three phases. The technical scheme based on the application can realize the following technical effects: during braking, a large amount of energy must be dissipated as heat by modifying the configuration of the phases; the motor and/or the motor control unit can be prevented from overheating; braking may be more efficient; modifications to the construction can be easily applied and no additional components are required, thereby achieving cost-effective and easy manufacturing.

Description

Actuator for valves and fittings

Technical Field

The utility model relates to actuators for valves and fittings.

More specifically, an actuator for valves and fittings may include a three-phase asynchronous motor. In a simple construction, the three phases of the asynchronous motor may be directly connected to three phases of a three-phase alternating current power supply. Such actuators are well known in the art and are commonly used, for example, in industrial applications.

Background

In motion, the valve or fitting may have a large momentum while the rotor of the motor has angular momentum. In addition to this, asynchronous motors generally have no braking momentum when they are switched off. Therefore, when the motor is stopped by cutting off the power supply at a desired position, these momentum cause the motor to rotate further. This may lead to incorrect positioning of the valve or fitting. Therefore, it is known to attach a separate brake unit that brakes the motor. However, such a brake unit requires additional space and increases costs.

SUMMERY OF THE UTILITY MODEL

The present invention seeks to improve the accuracy of such actuators while maintaining low costs.

In particular, the utility model relates to an actuator for valves and fittings comprising a three-phase asynchronous motor and a braking unit for braking the three-phase asynchronous motor, wherein the braking unit is configured to modify the configuration of at least one of the three phases.

The braking unit actively brakes the motor to counteract the momentum, thereby stopping the motor at a desired position. The brake unit is configured to modify a configuration of at least one of the three phases of the motor. This improves the accuracy. Also, a separate brake unit is not required, which reduces costs.

In one aspect, the braking unit is configured to interchange the configuration of two of the three phases. Thus, the voltage applied to the phase cancels the rotation of the motor. The motor stops faster.

In one aspect, the braking unit is configured to set at least two of the three phases to the same potential. This shorts the phases and inhibits commutation of the motor.

In one aspect, the modification to the configuration is applied only for a specified braking time. During braking, a large amount of energy must be dissipated as heat by modifying the configuration of the phases. Limiting the braking time may prevent overheating of the motor and/or the motor control unit.

In one aspect, the braking time is based on a current rotational speed or a current torque of the electric motor. Thereby, braking may be more efficient.

In one aspect, the brake unit includes at least one switching unit to modify wiring between the power supply port and the phases of the motor. Preferably, the switching unit is arranged between the power supply port and the phase of the at least one electric motor.

In another aspect of the utility model, the actuator includes an inverter for commutating a phase of the motor, and the brake unit is configured to control the inverter to modify a configuration of the phase of the motor. Thereby, modifications to the configuration can be easily applied and no additional member is required. This is also cost effective and easy to manufacture.

Specifically, the technical scheme of the utility model can realize the following technical effects: during braking, a large amount of energy must be dissipated as heat by modifying the configuration of the phases; the motor and/or the motor control unit can be prevented from overheating; braking may be more efficient; modifications to the configuration can be easily applied and no additional member is required, thereby reducing cost and facilitating manufacturing.

Drawings

FIG. 1 shows a block diagram of a valve actuator having a three-phase AC motor;

FIG. 2 illustrates a block diagram of a valve actuator having an actuator controller and a sensor;

fig. 3 shows a symbolic representation of a three-phase motor with a triangular configuration;

fig. 4 shows a symbolic representation of a three-phase motor with a Y-shaped configuration; and

fig. 5 shows different options for modifying the configuration of the three phases.

Detailed Description

Fig. 1 shows an example of an actuator 1. The actuator 1 comprises a valve 2 in a conduit 7 so that the flow of the conduit can be controlled.

The valve 2 is coupled to a transfer device 3. The transmission 3 is rotatably driven by a three-phase alternating current motor 4. The three motor phases L1, L2 and L3 are connected to a switching device 5, which switching device 5 comprises for example thyristors or inverters. The switching device 5 further comprises a braking unit configured to modify the configuration of the three motor phases L1, L2, L3.

The three-phase alternating current motor 4 may be internally configured in a triangular or Y-shaped configuration, as explained in detail with reference to fig. 3 and 4.

Fig. 2 shows another example of an actuator 1 similar to the actuator 1 of fig. 1. The actuator 1 includes an actuator controller 6. The actuator controller 6 drives three motor phases L1, L2, L3.

The actuator 1 additionally comprises a sensor 8 located at the conduit 7 and electrically coupled to the actuator controller 6. The sensor 8 may be a flow sensor or a temperature sensor. The actuator 1 may include additional sensors electrically coupled to the actuator controller 6. The actuator controller 6 also includes a brake unit configured to modify the configuration of the three motor phases L1, L2, L3.

Fig. 3 symbolically shows a three-phase alternating-current motor 4, in which the mutually independent phases L1, L2, L3 are configured in a triangular configuration.

Fig. 4 symbolically shows a three-phase electric motor 4, in which the mutually independent phases L1, L2, L3 are configured in a Y-shaped or star-shaped configuration.

Fig. 5 shows different options for modifying the configuration of the three motor phases L1, L2, L3 by means of the breaking unit 9. These configurations are applied only at disconnection.

In fig. 5(a), phase L1 is electrically connected to phase L2, thus shorting phase L1 to phase L2. Of course, the phase L1 and the phase L3 or the phase L2 and the phase L3 may be short-circuited.

In fig. 5(b), all of the three phases L1, L2, and L3 are short-circuited.

In FIG. 5(c), phase L1 and phase L2 are interchanged. Of course, it is also possible to interchange the phase L1 and the phase L3 or the phase L2 and the phase L3.

Claims

1. An actuator for valves and fittings, the actuator comprising a three-phase asynchronous motor and a braking unit for braking the three-phase asynchronous motor, characterized in that the braking unit is configured to modify the configuration of at least one of the three phases.

2. The actuator for valves and fittings of claim 1, wherein said brake unit is configured to interchange the configuration of two of said three phases.

3. The actuator for valves and fittings of claim 1, wherein said brake unit is configured to set at least two of said three phases to the same electrical potential.

4. The actuator for valves and fittings of claim 2, wherein said brake unit is configured to set at least two of said three phases to the same electrical potential.

5. An actuator for valves and fittings according to claim 1, wherein the modification to the configuration is applied only for a specified braking time.

6. An actuator for valves and fittings according to claim 2, wherein the modification to the configuration is applied only for a specified braking time.

7. An actuator for valves and fittings according to claim 3, wherein the modification to the configuration is applied only for a specified braking time.

8. An actuator for valves and fittings according to claim 4, wherein the modification to the configuration is applied only for a specified braking time.

9. Actuator for valves and fittings according to any of the claims 5-8, wherein the braking time is based on the current rotational speed or the current torque of the three-phase asynchronous motor.

10. Actuator for valves and fittings according to any of the claims 1 to 8, characterized in that the brake unit has at least one switching unit to modify the wiring between the power supply ports and the phases of the three-phase asynchronous motor.

11. Actuator for valves and fittings according to claim 9, characterized in that the brake unit has at least one switching unit to modify the wiring between the power supply ports and the phases of the three-phase asynchronous motor.

12. An actuator for valves and fittings according to any of claims 1 to 8, characterised in that the actuator comprises an inverter for commutating the phases of the three-phase asynchronous motor, and the brake unit is configured to control the inverter to modify the configuration of the phases of the three-phase asynchronous motor.

13. The actuator for valves and fittings of claim 9, wherein the actuator comprises an inverter for commutating the phases of the three-phase asynchronous motor, and the brake unit is configured to control the inverter to modify the configuration of the phases of the three-phase asynchronous motor.