KR102710661B1 - Rotor position estimation using acceleration information and sensorless motor control system using the same - Google Patents

Abstract

The rotor position estimator of the present invention may include an acceleration information reprocessing unit that outputs a speed error and a total torque of the rotor based on acceleration of the vehicle; and a rotor position estimation unit that outputs a position and a speed of the rotor based on the speed error and the total torque obtained from the acceleration information reprocessing unit and the position error of the rotor.

Description

{ROTOR POSITION ESTIMATION USING ACCELERATION INFORMATION AND SENSORLESS MOTOR CONTROL SYSTEM USING THE SAME}

The present invention relates to a position estimator, and more particularly, to a position estimator that uses acceleration information to improve robustness.

In general, the method of controlling a three-phase permanent magnet synchronous motor uses the difference between the current and the angular velocity and angle of the motor measured in real time and the command value. Accordingly, the importance of the encoder and resolver, which are sensors that measure the angular velocity of the motor, is emphasized. However, these devices are expensive and bulky, and have problems such as low reliability because they do not provide smooth output in noisy environments.

To solve this problem, sensorless control has recently emerged. Sensorless control is a control that estimates the angular velocity and angle of the motor without an encoder and a resolver. Therefore, unlike the existing method, since there is no speed measurement sensor, a motor driver that is cheaper and smaller than the existing one can be configured, and accurate output is possible even in a noisy environment. However, in the case of the position estimator used in the existing sensorless control, there is a problem that the rotor position estimation performance of the motor is greatly reduced due to the fluctuation of the load torque applied to the motor. Therefore, a rotor position estimation technology in sensorless that can solve this problem is required.

One object of the present invention is to provide a position estimator that uses acceleration information to improve robustness.

A rotor position estimator according to one embodiment may include an acceleration information reprocessing unit that outputs a speed error and a total torque of the rotor based on acceleration of the vehicle; and a rotor position estimation unit that outputs a position and a speed of the rotor based on the speed error and the total torque obtained from the acceleration information reprocessing unit and the position error of the rotor.

Here, the acceleration information reprocessing unit can calculate the speed error of the rotor based on the acceleration of the vehicle, gear efficiency coefficient, gear ratio, and wheel radius.

Here, the acceleration information reprocessing unit can calculate the total torque based on the moment of inertia, the speed error of the rotor, the friction coefficient, and the actual speed of the rotor.

Here, the acceleration information reprocessing unit can calculate the speed error of the rotor based on the equations below.

( : actual speed of the rotor, : acceleration of the vehicle, : Gear efficiency coefficient, : Gear ratio, : wheel radius, : Rotor speed error, : estimated rotor speed)

Here, the acceleration information reprocessing unit can calculate the total torque based on the equation below.

( : Total torque, : Moment of inertia, : coefficient of friction, : actual speed of the rotor)

Here, the rotor position estimation unit can calculate the position and speed of the rotor based on a state equation based on the position of the rotor and the speed of the rotor.

Here, the state equation can be set based on a state vector having the position of the rotor and the speed of the rotor as components, a system vector having the gain of the state variable as components, a first input matrix having the moment of inertia as components, a second input matrix having the gain of a position estimator as components, a first input vector having the total torque as components, and a second input vector having the position error of the rotor and the speed error of the rotor as components.

Here, the system vector can be configured as a fourth-order square matrix to remove the steady-state error of the position estimator.

A method for estimating a rotor position according to one embodiment of the present invention is a method for estimating a rotor position performed by at least one processor, the method including: a step of obtaining an acceleration of a vehicle and a position error of a rotor; a step of calculating a speed error and a total torque of the rotor based on the obtained acceleration of the vehicle; and a step of calculating a position and a speed of the rotor based on the calculated speed error and total torque and the position error of the rotor.

Here, the step of calculating the speed error of the rotor and the total torque may include the step of calculating the speed error of the rotor based on the acceleration of the vehicle, the gear efficiency coefficient, the gear ratio, and the wheel radius.

Here, the step of calculating the speed error of the rotor and the total torque may include the step of calculating the total torque based on the moment of inertia, the speed error of the rotor, the friction coefficient, and the actual speed of the rotor.

Here, the step of calculating the speed error and total torque of the rotor may be a step of calculating the speed error of the rotor using the equations below.

( : actual speed of the rotor, : vehicle acceleration, : Gear efficiency coefficient, : Gear ratio, : wheel radius, : Rotor speed error, : estimated rotor speed)

Here, the step of calculating the speed error of the rotor and the total torque may be a step of calculating the total torque using the equation below.

( : Total torque, : Moment of inertia, : coefficient of friction, : actual speed of the rotor)

Here, the step of calculating the position and speed of the rotor may be a step of using a state equation based on the position of the rotor and the speed of the rotor.

Here, the state equation can be set based on a state vector having the position of the rotor and the speed of the rotor as components, a system vector having the gain of the state variable as components, a first input matrix having the moment of inertia as components, a second input matrix having the gain of a position estimator as components, a first input vector having the total torque as components, and a second input vector having the position error of the rotor and the speed error of the rotor as components.

Here, the system vector can be configured as a fourth-order square matrix to remove the steady-state error of the position estimator.

Here, a computer program stored in a computer-readable recording medium can be provided to execute the above-described rotor position estimation method.

A sensorless motor control system according to one embodiment includes an acceleration sensor for detecting acceleration of a vehicle; an error extractor for extracting a position error of a rotor; and a rotor position estimator for estimating a position and a speed of the rotor. The rotor position estimator may include an acceleration information reprocessing unit for outputting a speed error and a total torque of the rotor based on the acceleration of the vehicle acquired from the acceleration sensor; and a rotor position estimating unit for outputting a position and a speed of the rotor based on the speed error and the total torque acquired from the acceleration information reprocessing unit and the position error of the rotor acquired from the error extractor.

According to one embodiment of the present invention, a position estimator using acceleration information to improve robustness can be provided.

Figures 1 and 2 are drawings for explaining sensorless control of a conventional vehicle drive motor.
FIG. 3 is a drawing for explaining a position estimator according to one embodiment of the present invention.
FIG. 4 is a drawing for explaining an acceleration information reprocessing unit according to one embodiment of the present invention.
FIG. 5 is a drawing for explaining a rotor position estimation unit according to one embodiment of the present invention.
FIG. 6 is a flowchart of a rotor position estimation method according to one embodiment of the present invention.
FIG. 7 and FIG. 8 are graphs comparing the performance of the position estimator of the prior art and the present invention when there is a sudden change in torque load in a signal injection-based sensorless control method.
FIG. 9 and FIG. 10 are graphs comparing the performance of the position estimator of the prior art and the present invention when there is a sudden change in torque load in a sensorless control method based on counter electromotive force.
FIG. 11 and FIG. 12 are graphs comparing the performance of the position estimator of the prior art and the present invention when a short and strong torque load is applied in a signal injection-based sensorless control method.
FIG. 13 and FIG. 14 are graphs comparing the performance of the position estimator of the prior art and the present invention when a short and strong torque load is applied in a sensorless control method based on counter electromotive force.
Figures 15 and 16 are graphs comparing the effectiveness of the position estimator of the prior art and the present invention when slip occurs.

Since the embodiments described in this specification are intended to clearly explain the idea of the present invention to a person having ordinary skill in the art to which the present invention pertains, the present invention is not limited to the embodiments described in this specification, and the scope of the present invention should be interpreted to include modified or altered examples that do not depart from the idea of the present invention.

The terms used in this specification have been selected from commonly used terms that are as much as possible in consideration of their functions in the present invention, but this may vary depending on the intention of a person with ordinary knowledge in the technical field to which the present invention belongs, precedents, or the emergence of new technologies. However, if a specific term is defined and used with an arbitrary meaning, the meaning of that term will be described separately. Accordingly, the terms used in this specification should be interpreted based on the actual meaning of the term and the overall contents of this specification, not simply the name of the term.

The drawings attached to this specification are intended to facilitate explanation of the present invention, and shapes depicted in the drawings may be exaggerated as necessary to help understanding of the present invention, and therefore the present invention is not limited by the drawings.

In cases where it is determined that a specific description of a known configuration or function related to the present invention in this specification may obscure the gist of the present invention, a detailed description thereof will be omitted as necessary.

Figures 1 and 2 are drawings for explaining sensorless control of a conventional vehicle drive motor. Figure 1 is a drawing for explaining a sensorless control flow, and Figure 2 is a drawing for explaining a weight according to an estimated speed.

Referring to Figures 1 and 2, when the motor rotates at high speed, the rotor position error ( ) can be extracted. Conversely, when the motor is stopped and in a low-speed state, the rotor position error can be extracted mainly through a sensorless method based on signal injection. Therefore, in order to naturally perform sensorless control in all speed ranges, the speed can be divided into three ranges as shown in Fig. 2, and the extracted position errors can be multiplied by weight functions and used.

The position error of the rotor extracted as above is input to the position estimator, and the position estimator can estimate the position and speed of the rotor. The estimated position of the rotor can be used in the motor driving system, and thus a sensorless control system that drives the motor without a rotor position sensor can be completed.

However, since the conventional position estimator is designed to utilize only electrical information on the motor drive system, it has an obvious limitation that it is vulnerable to physical disturbances such as external torque applied to the motor. Recently, numerous dynamic sensors are built into vehicles for active control systems. Therefore, various physical information of the vehicle can be obtained from the dynamic sensors. This means that the information of these sensors can also be utilized when designing a position estimator for sensorless control of the vehicle drive motor.

The present invention proposes a position estimator that uses information obtained from a dynamic sensor built into a vehicle, unlike a position estimator that uses only electrical information on a conventional motor drive system. Specifically, the present invention can provide a position estimator that is robust to external torque fluctuations by utilizing information from an acceleration sensor, which is another dynamic sensor of the vehicle. In addition, since the present invention utilizes information from a sensor already installed in the vehicle, it has the advantage of not requiring time and cost for additional installation.

Below, the position estimator of the present invention is described in detail.

FIG. 3 is a drawing for explaining a position estimator according to one embodiment of the present invention. In the following, the operation of the position estimator can be interpreted as being performed by at least one processor included in the position estimator.

Referring to Fig. 3, a position estimator (100) according to one embodiment of the present invention may include an acceleration information reprocessing unit (10) and a rotor position estimation unit (30). The position estimator (100) may detect a position error of the rotor from the outside ( ) and vehicle acceleration ( ) information can be obtained. Specifically, the position estimator (100) can obtain the position error of the rotor from an error extractor (not shown) of the sensorless motor control system.

The error extractor can extract the rotor position error by a sensorless method based on back electromotive force or signal injection. Specifically, the error extractor can use a sensorless method based on back electromotive force when the motor rotates at high speed, and can use a sensorless method based on signal injection when the motor is stopped and at low speed.

In addition, the position estimator (100) can obtain the acceleration of the vehicle from the acceleration sensor. The acceleration sensor is a dynamic sensor built into the vehicle and can transmit the acceleration information of the vehicle sensed to the position estimator (100).

The position estimator (100) can estimate the final position of the rotor by reprocessing the acceleration of the vehicle acquired from the acceleration sensor through the acceleration information reprocessing unit. Specifically, the position estimator (100) can input the acquired acceleration into the acceleration information reprocessing unit (10). The acceleration information reprocessing unit (10) can calculate the speed error and total torque of the rotor based on the input acceleration of the vehicle. The acceleration information reprocessing unit (10) can transfer the calculated speed error and total torque of the rotor to the rotor position estimation unit (30).

The rotor position estimation unit (30) can obtain the rotor speed error and total torque from the acceleration information reprocessing unit (10). In addition, the rotor position estimation unit (30) can obtain information on the rotor position error from the outside (e.g., an error extractor). The position estimator (100) can input the rotor speed error, total torque, and rotor position error into the rotor position estimation unit (30). The rotor position estimation unit (30) can estimate and/or output the rotor position and speed based on the input values.

A position estimator (100) may be included in a sensorless motor control system. The sensorless motor control system may include an acceleration sensor, an error extractor, and a rotor position estimator (100).

The acceleration sensor included in the sensorless motor control system is a sensor built into the vehicle and can detect the acceleration of the vehicle. The error extractor included in the sensorless motor control system can extract the position error of the rotor. The position estimator (100) included in the sensorless motor control system can estimate the position and speed of the rotor based on the values obtained from the acceleration sensor and the error extractor.

Hereinafter, the acceleration information reprocessing unit (10) and the rotor position estimation unit (30) included in the position estimator (100) will be described in detail with reference to FIGS. 2 and 3.

FIG. 4 is a drawing for explaining an acceleration information reprocessing unit according to one embodiment of the present invention.

Referring to Fig. 4, the operation flow of the acceleration information reprocessing unit (10) according to one embodiment of the present invention can be confirmed. The acceleration information reprocessing unit (10) can calculate the rotor speed error using the acceleration of the vehicle obtained from the outside (e.g., acceleration sensor). Specifically, the acceleration information reprocessing unit (10) can calculate the acceleration of the vehicle ( ), gear efficiency coefficient ( ), gear ratio( ) and wheel radius ( ) can be used to calculate the rotor speed error.

As in the operation flow of Fig. 4, the acceleration information reprocessing unit (10) can calculate the rotor speed error based on [Mathematical Formula 1] and [Mathematical Formula 2] below.

( : actual speed of the rotor, : acceleration of the vehicle, : Gear efficiency coefficient, : Gear ratio, : wheel radius, : Rotor speed error, : estimated rotor speed)

In addition, the acceleration information reprocessing unit (10) can calculate the total torque of the rotor by using the speed error of the rotor obtained from an external source (e.g., an error extractor). Specifically, the acceleration information reprocessing unit (10) can calculate the total torque based on the moment of inertia, the speed error of the rotor, the friction coefficient, and the actual speed of the rotor.

As in the operation flow of Fig. 4, the acceleration information reprocessing unit (10) can calculate the total torque based on [Mathematical Formula 3] below.

( : Total torque, : Moment of inertia, : coefficient of friction, : actual speed of the rotor)

The acceleration information reprocessing unit (10) can transmit the calculated rotor speed error and total torque to the rotor position estimation unit (30).

FIG. 5 is a drawing for explaining a rotor position estimation unit according to one embodiment of the present invention.

Referring to Fig. 5, the operational flow of the rotor position estimation unit (30) according to one embodiment of the present invention can be confirmed. The rotor position estimation unit (30) obtains the rotor position error ( ) and the acceleration information reprocessing unit (10) can estimate the position and speed of the rotor. Specifically, the rotor position estimation unit (30) can calculate the position and speed of the rotor based on a state equation based on the position and speed of the rotor.

At this time, the state equation can be set based on a state vector having the position of the rotor and the speed of the rotor as components, a system vector having the gain of the state variable as components, a first input matrix having the moment of inertia as components, a second input matrix having the gain of the position estimator as components, a first input vector having the total torque as components, and a second input vector having the position error of the rotor and the speed error of the rotor as components. The state equation can be expressed as shown in [Mathematical Formula 4] below.

(State vector: , : First input vector, Second input vector: , : Gains of the position estimator)

In the state equation, the matrix multiplied with the state vector is a system vector, the matrix multiplied with the first input vector may be a first input matrix, and the matrix multiplied with the second input vector may be a second input matrix. At this time, the system vector may be configured as a fourth-order square matrix to remove the steady-state error of the position estimator (100). In order to design as a fourth-order system, the state vector is a first state variable, And the second state variable is may include.

In addition, each of the gains of the position estimator may mean the gain of the first state variable, the gain of the second state variable, the gain of the position error, and the gain of the velocity error. Specifically, is the gain of the first state variable in the first row of the state equation, is the gain of the second state variable in the first row of the state equation. is the gain of the first state variable in row 2 of the state equation, is the gain of the second state variable in row 2 of the state equation. is the gain of the second state variable in row 3 of the state equation.

is the gain of the position error in the first row of the state equation, is the gain in velocity error in row 1 of the state equation. is the gain of the position error in row 2 of the state equation, is the gain of velocity error in row 2 of the state equation. is the gain of position error in row 3 of the state equation, is the gain in velocity error in row 3 of the state equation. is the gain of position error in row 4 of the state equation.

As described above, the rotor position estimation unit (30) is designed as a 4th-order system, so that the estimation performance can be robust to speed and torque fluctuations by eliminating the error in the steady state. Hereinafter, the position estimator (100) of the present invention will be analyzed in detail through the transfer function.

The position of the rotor estimated by the position estimator (100) of the present invention ) is the actual rotor position ( ), the difference between the actual total torque and the total torque obtained by acceleration ( ) and the difference between the velocity obtained by the estimated velocity and acceleration ( ) has the same relationship as [Mathematical Formula 5] below.

( : Transfer function of actual rotor position with respect to estimated rotor position, : Transfer function of the difference between the actual total torque for the estimated rotor position and the total torque obtained by acceleration, : Transfer function of the difference between the estimated velocity and the velocity obtained by the acceleration for the estimated rotor position)

if , , , , , , , , , , , Then, each transfer function is , , This means that even if an error occurs in the total torque of the acceleration information reprocessing unit (10), the position can be estimated without error or delay.

Also, according to the final value theorem, The steady state error is 0, and the appropriate class Even if an error occurs in the velocity error of the acceleration information reprocessing unit (10) through selection of , the error and delay of the estimated position can be alleviated.

In addition, since the estimated speed is used in the acceleration information reprocessing process, the estimation performance of the speed is also important for high position estimation performance. The rotor speed (estimated by the position estimator (100) of the present invention) ) is the actual rotor position ( ) and the difference between the actual total torque and the total torque obtained by acceleration ( ), the difference between the estimated velocity and the velocity obtained by acceleration ( ) has the same relationship as [Mathematical Formula 6] below.

( : Transfer function of actual rotor position with respect to estimated rotor speed, : Transfer function of the difference between the actual total torque for the estimated rotor speed and the total torque obtained by acceleration, : Transfer function of the difference between the estimated speed and the speed obtained by acceleration for the estimated rotor speed)

If the gains of the position estimator (100) have the same values as above, each transfer function

, , This is it.

thus class While keeping it as is class By increasing the bandwidth by adjusting the acceleration information reprocessing unit (10), the estimation performance can be improved without affecting the sensitivity to errors occurring in the output.

Fig. 6 is a flowchart of a rotor position estimation method according to one embodiment of the present invention. The rotor position estimation method of Fig. 6 can be performed by at least one processor included in a sensorless motor control system or at least one processor included in a position estimator (100).

Referring to FIG. 6, a method for estimating a rotor position according to an embodiment of the present invention may include a step of obtaining acceleration of a vehicle (S100), a step of obtaining a position error of a rotor (S200), a step of calculating a speed error of the rotor and a total torque (S300), and a step of calculating the position and speed of the rotor (S400). In FIG. 6, steps S100 to S400 are illustrated as being performed sequentially, but are not limited thereto, and the order of each step may be changed or some steps may be performed simultaneously. For example, steps S100 and S200 may be performed simultaneously, but are not limited thereto.

The step (S100) of obtaining the acceleration of the vehicle may be a step in which the position estimator (100) obtains acceleration information of the vehicle from an acceleration sensor. The step (S200) of obtaining the position error of the rotor may be a step in which the position estimator (100) obtains the position error of the rotor from an error extractor.

The step (S300) of calculating the rotor speed error and total torque may be a step in which the acceleration information reprocessing unit (10) included in the position estimator (100) calculates the rotor speed error and total torque using the vehicle acceleration acquired in step S100. A detailed description of step S300 may overlap with the contents of FIG. 4, and thus is omitted.

The step (S400) of calculating the position and speed of the rotor may be a step of estimating the position and speed of the rotor by using the speed error and total torque of the rotor calculated in step S300 and the position error of the rotor obtained in step S200. A detailed description of step S400 may overlap with the contents of Fig. 5, and thus is omitted.

FIG. 7 and FIG. 8 are graphs comparing the performance of the position estimator of the conventional and the present invention when there is a sudden change in torque load in a signal injection-based sensorless control method. FIG. 7 and FIG. 8 are graphs when the speed of the motor is controlled to 200 rpm and the load is varied from 10% to 90% of the rated torque. Since the motor operates at a low speed, the position error of the rotor can be extracted by the signal injection-based sensorless method.

Fig. 7 is a graph for a conventional position estimator, and Fig. 8 is a graph for a position estimator of the present invention. Referring to Figs. 7 and 8, it can be confirmed that the conventional position estimator has a large impact on the result value of the position estimator as a sudden change in torque load occurs. On the other hand, the position estimator of the present invention uses a value obtained from an acceleration sensor of the vehicle, not just electrical information on the motor drive system, so it can be confirmed that even if there is a sudden change in the motor torque load, the result value of the position estimator is not affected, and the result value is stably output.

FIGS. 9 and 10 are graphs comparing the performance of the position estimator of the prior art and the present invention when there is a sudden change in torque load in a sensorless control method based on a counter electromotive force. FIGS. 9 and 10 are graphs when the speed of the motor is controlled to 200 rpm and the load is varied from 10% to 90% of the rated torque. Since the motor operates at high speed, the position error of the rotor can be extracted by the sensorless method based on a counter electromotive force.

Fig. 9 is a graph for a conventional position estimator, and Fig. 10 is a graph for a position estimator of the present invention. Referring to Figs. 9 and 10, it can be confirmed that the conventional position estimator has a large impact on the result value of the position estimator as a sudden change in torque load occurs. On the other hand, the position estimator of the present invention uses a value obtained from an acceleration sensor of the vehicle, not just electrical information on the motor drive system, so it can be confirmed that even if there is a sudden change in the motor torque load, the result value of the position estimator is not affected, and the result value is stably output.

Referring to FIGS. 8 to 10, as the motor operates at low/high speed, a sensorless control method based on signal injection or counter electromotive force can be applied as a method for extracting a rotor position error. Even if both methods are applied, it can be confirmed that the result value of the position estimator of the present invention is robust to load fluctuations.

FIG. 11 and FIG. 12 are graphs comparing the performance of the position estimator of the prior art and the present invention when a short and strong torque load is applied in a signal injection-based sensorless control method. FIG. 11 and FIG. 12 are graphs when torque control is performed at 50% of the rated torque for the motor and the load is varied from 200 rpm to 800 rpm in just 0.6 seconds (50 times the rated torque is generated in 0.6 seconds). In addition, FIG. 11 and FIG. 12 are graphs when the position error of the rotor is extracted using the signal injection-based sensorless method.

Fig. 11 is a graph for a conventional position estimator, and Fig. 12 is a graph for a position estimator of the present invention. Referring to Figs. 11 and 12, it can be confirmed that the result value of the conventional position estimator is greatly affected by load fluctuations. On the other hand, the position estimator of the present invention uses values obtained from an acceleration sensor of the vehicle, not just electrical information on the motor drive system, so it can be confirmed that even if there is a rapid fluctuation in the motor torque load, the result value of the position estimator is not affected, and the result value is stably output.

FIG. 13 and FIG. 14 are graphs comparing the performance of the position estimator of the prior art and the present invention when a short and strong torque load is applied in a sensorless control method based on a counter electromotive force. FIG. 13 and FIG. 14 are graphs when torque control is performed at 50% of the rated torque for the motor and the load is varied from 4000 rpm to 4600 rpm in just 0.6 seconds (50 times the rated torque is generated in 0.6 seconds). In addition, FIG. 13 and FIG. 14 are graphs when the position error of the rotor is extracted using the sensorless method based on a counter electromotive force.

Fig. 13 is a graph for a conventional position estimator, and Fig. 14 is a graph for a position estimator of the present invention. Referring to Figs. 13 and 14, it can be confirmed that the result value of the conventional position estimator is greatly affected by load fluctuations. On the other hand, the position estimator of the present invention uses values obtained from an acceleration sensor of the vehicle as well as electrical information on the motor drive system, so that even if there is a rapid fluctuation in the motor torque load, it can be confirmed that the result value of the position estimator is not affected and the result value is stably output.

Referring to FIGS. 11 to 14, it can be confirmed that the result value of the position estimator of the present invention is robust to load fluctuations even when a short and strong torque load is applied and a sensorless control method based on signal injection or counter electromotive force is applied.

Figures 15 and 16 are graphs comparing the effectiveness of the position estimator of the prior art and the present invention when a slip occurs. Specifically, Figures 15 and 16 are graphs comparing the effectiveness of the position estimator when a slip occurs in which acceleration information is inaccurate, torque control is performed at 50% of the rated torque for the motor, and the speed of the motor is changed from 0 rpm to 1000 rpm while the load is stopped.

Fig. 15 is a graph for a conventional position estimator, and Fig. 16 is a graph for a position estimator of the present invention. Referring to Figs. 15 and 16, it can be confirmed that while the output value of the conventional position estimator is very unstable after a load change, the position estimator of the present invention can still operate effectively through bandwidth adjustment.

The method according to the embodiment may be implemented in the form of program commands that can be executed through various computer means and recorded on a computer-readable medium. The computer-readable medium may include program commands, data files, data structures, etc., alone or in combination. The program commands recorded on the medium may be those specially designed and configured for the embodiment or may be those known to and available to those skilled in the art of computer software. Examples of the computer-readable recording medium include magnetic media such as hard disks, floppy disks, and magnetic tapes, optical media such as CD-ROMs and DVDs, magneto-optical media such as floptical disks, and hardware devices specially configured to store and execute program commands such as ROMs, RAMs, flash memories, etc. Examples of the program commands include not only machine language codes generated by a compiler but also high-level language codes that can be executed by a computer using an interpreter, etc. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the embodiment, and vice versa.

Although the embodiments have been described above by way of limited examples and drawings, those skilled in the art may make various modifications and variations from the above description. For example, appropriate results may be achieved even if the described techniques are performed in a different order than the described method, and/or components of the described system, structure, device, circuit, etc. are combined or combined in a different form than the described method, or are replaced or substituted by other components or equivalents.

Therefore, other implementations, other embodiments, and equivalents to the claims are also included in the scope of the claims described below.

Claims (18)

An acceleration information reprocessing unit that outputs the rotor speed error and total torque based on the vehicle acceleration; and
It includes a rotor position estimation unit that outputs the position and speed of the rotor based on the speed error obtained from the acceleration information reprocessing unit and the total torque and the position error of the rotor,
The above acceleration information reprocessing unit calculates the speed error of the rotor based on the acceleration, gear efficiency coefficient, gear ratio and wheel radius of the vehicle.
Rotor position estimator.
delete In the first paragraph,
The above acceleration information reprocessing unit calculates the total torque based on the moment of inertia, the speed error of the rotor, the friction coefficient, and the actual speed of the rotor.
Rotor position estimator.
In the first paragraph,
The above acceleration information reprocessing unit calculates the speed error of the rotor based on the equations below.


( : actual speed of the rotor, : vehicle acceleration, : Gear efficiency coefficient, : Gear ratio, : wheel radius, : Rotor speed error, : estimated rotor speed)
Rotor position estimator.
In the third paragraph,
The above acceleration information reprocessing unit calculates the total torque based on the equation below.

( : Total torque, : Moment of inertia, : coefficient of friction, : actual speed of the rotor)
Rotor position estimator.
In the first paragraph,
The above rotor position estimation unit calculates the position and speed of the rotor based on a state equation based on the position of the rotor and the speed of the rotor,
The above state equation is set based on a state vector related to the position of the rotor and the speed of the rotor, a system vector related to the gain of the state variable, a first input matrix related to the moment of inertia, a second input matrix related to the gain of the position estimator, a first input vector related to the total torque, and a second input vector related to the position error of the rotor and the speed error of the rotor.
Rotor position estimator.
In Article 6,
The above state equation is set based on a state vector having the position of the rotor and the speed of the rotor as components, a system vector having the gain of the state variable as components, a first input matrix having the moment of inertia as components, a second input matrix having the gain of the position estimator as components, a first input vector having the total torque as components, and a second input vector having the position error of the rotor and the speed error of the rotor as components.
Rotor position estimator.
In Article 7,
The above system vector is composed of a 4th order square matrix to remove the steady state error of the position estimator.
Rotor position estimator.
In a method for estimating a rotor position performed by at least one processor,
A step of obtaining the acceleration of the vehicle and the position error of the rotor;
A step of calculating the rotor speed error and total torque based on the acquired vehicle acceleration; and
A step of calculating the position and speed of the rotor based on the calculated speed error and total torque and the position error of the rotor,
The step of calculating the speed error and total torque of the rotor includes the step of calculating the speed error of the rotor based on the acceleration of the vehicle, the gear efficiency coefficient, the gear ratio, and the wheel radius.
A method for estimating rotor position.
delete In Article 9,
The step of calculating the speed error and total torque of the rotor includes the step of calculating the total torque based on the moment of inertia, the speed error of the rotor, the friction coefficient, and the actual speed of the rotor.
A method for estimating rotor position.
In Article 9,
The step of calculating the speed error and total torque of the above rotor is a step of calculating the speed error of the above rotor using the equations below.


( : actual speed of the rotor, : vehicle acceleration, : Gear efficiency coefficient, : Gear ratio, : wheel radius, : Rotor speed error, : estimated rotor speed)
A method for estimating rotor position.
In Article 9,
The step of calculating the speed error and total torque of the above rotor is the step of calculating the total torque using the equation below.

( : Total torque, : Moment of inertia, : coefficient of friction, : actual speed of the rotor)
A method for estimating rotor position.
In Article 9,
The step of calculating the position and speed of the rotor is a step of using a state equation based on the position and speed of the rotor.
The above state equation is set based on a state vector related to the position of the rotor and the speed of the rotor, a system vector related to the gain of the state variable, a first input matrix related to the moment of inertia, a second input matrix related to the gain of the position estimator, a first input vector related to the total torque, and a second input vector related to the position error of the rotor and the speed error of the rotor.
A method for estimating rotor position.
In Article 14,
The above state equation is set based on a state vector having the position of the rotor and the speed of the rotor as components, a system vector having the gain of the state variable as components, a first input matrix having the moment of inertia as components, a second input matrix having the gain of the position estimator as components, a first input vector having the total torque as components, and a second input vector having the position error of the rotor and the speed error of the rotor as components.
A method for estimating rotor position.
In Article 15,
The above system vector is composed of a 4th order square matrix to remove the steady state error of the position estimator.
A method for estimating rotor position.
A computer program stored in a computer-readable recording medium to execute a rotor position estimation method described in any one of claims 9, 11 to 16.
An acceleration sensor that detects the acceleration of a vehicle;
An error extractor for extracting the position error of the rotor; and
Includes a rotor position estimator that estimates the position and speed of the rotor,
The above rotor position estimator is,
An acceleration information reprocessing unit that outputs the rotor speed error and total torque based on the acceleration of the vehicle obtained from the acceleration sensor; and
It includes a rotor position estimation unit that outputs the position and speed of the rotor based on the speed error and the total torque obtained from the acceleration information reprocessing unit and the rotor position error obtained from the error extractor.
The above acceleration information reprocessing unit calculates the speed error of the rotor based on the acceleration, gear efficiency coefficient, gear ratio and wheel radius of the vehicle.
Sensorless motor control system.