A method and device for estimating the torque output of a motor control and a motor controller

Abstract

The present invention provides a method and device for estimating the torque output of a motor control and a motor controller, which relate to the technical field of motor control and include: pre-obtaining the rated current, maximum current of the object to be estimated, the rated value of the heat integral generated during operation, and the maximum value of the heat integral generated during operation; receiving a torque estimation signal, obtaining the current current according to the torque estimation signal and performing preprocessing; calculating the heat integral at the current moment according to the current current, so as to estimate the heat integral at the target moment according to the heat integral at the current moment, the current current and a preset integral function; determining the operating state of the object to be estimated at the target moment according to the relationship between the current current and the rated current and the maximum current, and the relationship between the heat integral at the current moment, the heat integral at the target moment and the rated value of the heat integral and the maximum value of the heat integral, so as to estimate the torque output at the target moment, and solving the problems that the existing method cannot accurately estimate the torque output ability and the motor output does not match the actual motor state.

Claims

1. A method for estimating the torque output of a motor control, characterized in that, it includes: Pre-acquire the rated current, maximum current of the object to be estimated, as well as the rated value of the heat integral generated during operation and the maximum value of the heat integral generated during operation. The object to be estimated is a motor or a combination of a motor and other heating units in a motor controller; Receive a torque estimation signal, obtain the current current according to the torque estimation signal and perform preprocessing; Calculate the heat integral at the current moment according to the current current, so as to estimate the heat integral at the target moment according to the heat integral at the current moment, the current current and a preset integral function; Determine the operating state of the object to be estimated at the target moment according to the relationship between the current current and the rated current and the maximum current, and the relationship between the heat integral at the current moment, the heat integral at the target moment and the rated value of the heat integral and the maximum value of the heat integral, so as to estimate the torque output at the target moment; The determining the operating state of the object to be estimated at the target moment to estimate the torque output at the target moment includes the following: Judge whether the heat integral at the target moment exceeds the rated value of the heat integral. If not, calculate the torque output at the target moment according to the maximum current; If so, determine the operating state of the object to be estimated according to the current current and the heat integral at the current moment, and determine whether to perform output derating according to the operating state of the object to be estimated, so as to estimate the torque output at the target moment; The determining the operating state of the object to be estimated according to the current current and the heat integral at the current moment, and determining whether to perform output derating according to the operating state of the object to be estimated to estimate the torque output at the target moment includes: If the current current does not exceed the rated current and the heat integral at the current moment exceeds the rated value of the heat integral, determine that the operating state is restored output after switching, and estimate the torque output at the target moment based on the change of the current from the current at the time of switching the operating state of the object to be estimated to the maximum current; If the current current exceeds the rated current, judge whether the operating state is continuous increase of output according to the heat integral at the current moment. If so, perform output derating and estimate the torque output at the target moment based on the change from the maximum current to the rated current; if not, determine that the operating state is switched to reduced output, and estimate the torque output at the target moment based on the change of the current from the current at the time of switching the operating state to the rated current.

2. The estimation method according to claim 1, characterized in that: When the operating state of the object to be estimated is switched to restored output, determine the current change rate according to the ratio between the difference between the heat integral at the target moment and the rated value of the heat integral and the difference between the heat integral corresponding to the time of switching the operating state and the rated value of the heat integral; When the operating state of the object to be estimated is continuous increase of output, determine the current change rate according to the ratio between the difference between the heat integral at the target moment and the rated value of the heat integral and the difference between the maximum value of the heat integral and the rated value of the heat integral; When the operating state of the object to be estimated is switched to reduced output, determine the current change rate according to the ratio between the difference between the heat integral at the target moment and the heat integral at the time of switching the operating state and the difference between the maximum value of the heat integral and the heat integral at the time of switching the operating state.

3. The estimation method according to claim 2, It is characterized in that: When the operating state of the object to be estimated is that the output continuously increases, it is set that after reaching the preset reference time, the output current is limited, wherein the target time exceeds the preset time; Calculate the reference thermal integral value corresponding to the preset reference time, and calculate the current output at the reference time based on the change from the maximum current to the current current; Based on the reference thermal integral value and the current output at the reference time, determine whether to perform output derating to estimate the torque output at the target time.

4. The estimation method according to claim 1, It is characterized in that, The estimation of the thermal integral at the target time according to the thermal integral, the current current and the preset integral function at the current time includes: Determine the change amount of the thermal integral according to the square difference between the current current and the rated current, the product of the preset integral coefficient and the estimation time period, wherein the estimation time period is the time period during which the target time changes relative to the current time; Determine the thermal integral at the target time according to the thermal integral at the current time and the change amount of the thermal integral.

5. The estimation method according to claim 1, It is characterized in that, The calculation of the torque output at the target time according to the maximum current includes: Determine the maximum current as the current output at the target time; Calculate the torque output at the target time according to the preset current and torque conversion relationship.

6. The estimation method according to claim 1, It is characterized in that: Estimate the torque output at the target time by replacing the current with torque according to the preset current and torque conversion relationship.

7. A device for estimating the torque output of a motor control, It is characterized in that, Including: An acquisition module for pre-acquiring the rated current, the maximum current of the object to be estimated, as well as the rated value of the thermal integral generated during operation and the maximum value of the thermal integral generated during operation, where the object to be estimated is a motor or a combination of a motor and other heating units in a motor controller; A preprocessing module for receiving a torque estimation signal, acquiring the current current according to the torque estimation signal and performing preprocessing; A calculation module for calculating the thermal integral at the current time according to the current current, so as to estimate the thermal integral at the target time according to the thermal integral at the current time, the current current and the preset integral function; A processing module for determining the operating state of the object to be estimated at the target time according to the relationship between the current current and the rated current and the maximum current, as well as the relationship between the thermal integral at the current time, the thermal integral at the target time and the rated value of the thermal integral and the maximum value of the thermal integral, so as to estimate the torque output at the target time; The determination of the operating state of the object to be estimated at the target time to estimate the torque output at the target time includes the following: Judge whether the thermal integral at the target time exceeds the rated value of the thermal integral. If not, calculate the torque output at the target time according to the maximum current; If so, determine the operating state of the object to be estimated according to the current current and the thermal integral at the current time, and determine whether to perform output derating according to the operating state of the object to be estimated to estimate the torque output at the target time; The determination of the operating state of the object to be estimated according to the current current and the thermal integral at the current time, and the determination of whether to perform output derating according to the operating state of the object to be estimated to estimate the torque output at the target time includes: If the current current does not exceed the rated current and the thermal integral at the current moment exceeds the rated value of the thermal integral, it is determined that the operating state is restored after switching, and the torque output at the target moment is estimated based on the change of the current from the operating state switching of the estimation object to the maximum current; If the current current exceeds the rated current, it is judged whether the operating state is continuous increase of output according to the thermal integral at the current moment. If so, the output is derated, and the torque output at the target moment is estimated based on the change from the maximum current to the rated current; if not, it is determined that the operating state is switched to reduce output, and the torque output at the target moment is estimated based on the change of the current from the operating state switching to the rated current.

8. A motor controller, Characterized in that: The torque output of the motor control torque output estimation device described in claim 7 is applied to output the torque output at the target moment for control.

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