Motor control device, motor controller, and motor control method

Abstract

The invention discloses a motor control device, a motor controller and a motor control method. A motor control device includes: a resolver that calculates a rotation angle of a motor on the basis of a voltage detection value from a stator winding; and a motor controller that calculates a rotation angle for control by extrapolating the rotation angle calculated by the resolver based on a time difference between a control timing of the resolver and a voltage sensing timing, and controls the motor by using the rotation angle for control.

Description

[0001] Related applications

[0002] This application claims the benefit and priority of Korean Patent Application No. 10-2024-0115313, filed on August 27, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This invention relates to electric motor control. Background Technology

[0004] In permanent magnet synchronous motors (PMSMs), which are commonly used in environmentally friendly vehicles, accurate detection of rotor position is crucial.

[0005] PMSMs require high-precision torque control, and accurate rotor position is crucial for generating optimal torque by applying current to the stator at the right time. Furthermore, detecting the precise rotor position minimizes losses in motor control and enables efficient energy utilization. In electric vehicles requiring precise speed control, knowing the exact rotor position is essential for accurate speed control.

[0006] Devices used to measure the position and speed of an electric motor include Hall sensors, encoders, and resolvers.

[0007] Hall effect sensors detect the position of a magnet to determine the position of a rotor. While Hall effect sensors are relatively simple and inexpensive, their low resolution limits their application in high-precision control.

[0008] Optical encoders use patterns on a disk to detect rotational position, while magnetic encoders detect the position of a magnet using a magnetic sensor. Encoders provide relatively high-resolution position information, enabling precise motor control.

[0009] Rotor transformers use analog signals to measure the rotation angle of an electric motor. They provide instantaneous absolute rotor position information and are suitable for industrial and automotive applications due to their robustness and high reliability.

[0010] The electric motor device may include a motor controller that generates motor control signals, and the resolver may include a resolver calculator that calculates the rotation angle of the motor. The motor controller and the resolver calculator may be configured as separate integrated circuits (ICs) and may have control periods and sensing periods respectively, depending on their respective PWM (pulse width modulation) signals.

[0011] Therefore, a time difference may occur between the control timing of the motor controller and the sensing timing of the resolver. This time difference can result in a discrepancy between the motor rotation angle detected by the controller via the resolver and the actual rotation angle of the motor. This difference can reduce the stability of the motor control and cause torque ripple in the motor.

[0012] In particular, the control period of the motor controller can be varied, and if the aforementioned time difference fluctuates due to this variation, the stability of the motor control can be further reduced, and torque ripple can become more pronounced. Summary of the Invention

[0013] In light of this background, in one aspect, this disclosure aims to provide a motor control technique that can enhance the stability of motor control. In another aspect, the invention aims to provide a motor control technique that minimizes torque ripple in the motor. In yet another aspect, the invention aims to provide a motor control technique that allows the rotation angle of the motor detected during control timing to more closely resemble the actual rotation angle of the motor.

[0014] In view of the above, embodiments of the present disclosure provide an electric motor control device, including: a rotary transformer that calculates the rotation angle of the electric motor based on voltage sensing values ​​from the stator windings; and an electric motor controller that calculates a rotation angle for control by extrapolating the rotation angle calculated by the rotary transformer based on the time difference between the control timing of the rotary transformer and the voltage sensing timing, and controls the electric motor by using the rotation angle for control.

[0015] The rotary transformer can generate voltage sensing values ​​in the first time period, and the motor controller can control the motor in the second time period.

[0016] The rotary transformer can generate a voltage sensing value in a first time period formed according to a first PWM (pulse width modulation) signal, and the motor controller can control the motor in a second time period formed according to a second PWM signal different from the first PWM signal.

[0017] The motor controller can control the motor by changing the second time period.

[0018] The first time period and the second time period can have the same duration during the first time interval, and the first time period and the second time period can have different durations during the second time interval.

[0019] The resolver may include: a rotor winding positioned on the rotating shaft of an electric motor; a first stator winding wherein a first induced voltage is generated by an electromagnetic field formed in the rotor winding; and a second stator winding wherein a second induced voltage is generated by an electromagnetic field formed in the rotor winding; and a resolver calculator that generates voltage sensed values ​​for the first and second induced voltages using an ADC (analog-to-digital converter) and calculates the rotation angle of the electric motor based on the voltage sensed values.

[0020] The excitation voltage can be supplied to the rotor winding according to the excitation PWM (pulse width modulation) signal, and the rotary transformer calculator can sense the first induced voltage and the second induced voltage according to the sensing PWM signal, wherein the sensing PWM signal lags behind the excitation PWM signal by a certain amount of time.

[0021] The first stator winding and the second stator winding can be arranged such that their magnetic fields are orthogonal to each other.

[0022] The resolver calculator can include ATO (Angle Tracking Observer) logic and can calculate the rotation angle of the motor based on the ATO logic.

[0023] Another embodiment of this disclosure provides a motor controller, comprising: a resolver signal processing unit that obtains the rotation angle of the motor and the sensing timing of the resolver from the resolver; a control value calculation unit that calculates the rotation angle for control by checking the control timing and extrapolating the rotation angle calculated by the resolver based on the time difference between the control timing and the sensing timing of the resolver, and determines a control value for the motor by using the rotation angle for control; and a control signal output unit that outputs a control signal corresponding to the control value to the motor.

[0024] The motor controller may further include an ADC (analog-to-digital converter) that senses control values ​​for the motor, wherein a control value calculation unit checks the sensing timing of the ADC based on the control timing.

[0025] At a certain point in time, the sensing period of the rotary transformer and the control period of the control value calculation unit can have different durations.

[0026] The control period of the control value calculation unit can be varied.

[0027] The excitation PWM (pulse width modulation) signal can provide a reference for the excitation voltage of the rotary transformer, and the sensing PWM signal can provide a reference for the sensing timing of the induced voltage of the stator winding. There is a phase difference between the excitation PWM signal and the sensing PWM signal.

[0028] The stator windings can be arranged such that their magnetic fields are orthogonal to each other.

[0029] Another embodiment of this disclosure provides a motor control method, comprising: checking a control timing; obtaining a rotation angle of the motor and a sensing timing of the rotary transformer from a rotary transformer; calculating a rotation angle for control by extrapolating the rotation angle calculated by the rotary transformer based on the time difference between the control timing and the sensing timing of the rotary transformer; determining a control value for the motor by using the rotation angle for control; and outputting a control signal corresponding to the control value to the motor.

[0030] At any given time, the sensing period of the resolver and the control period for the motor can have different durations.

[0031] The control period can be varied.

[0032] As described above, according to this disclosure, the rotation angle of the motor detected during control timing can be made more similar to the actual rotation angle of the motor. Furthermore, according to this disclosure, the stability of motor control can be enhanced, and torque ripple in the motor can be minimized. Attached Figure Description

[0033] Figure 1 This is a configuration diagram of the electric motor device according to the embodiment.

[0034] Figure 2 This is a configuration diagram of a rotary transformer according to an embodiment.

[0035] Figure 3 This is a view showing the main waveforms of a rotary transformer according to an embodiment.

[0036] Figure 4 This is a configuration diagram of a motor controller according to an implementation method.

[0037] Figure 5 This is a view showing the main waveforms of the motor controller and the rotary transformer according to the embodiment.

[0038] Figure 6 This is a view illustrating the extrapolation process according to an implementation method.

[0039] Figure 7 This is a flowchart of a motor control method according to an implementation method.

[0040] Figure 8 This is a view showing the motor output waveform when the control value is calculated without extrapolation.

[0041] Figure 9 This is a view showing the motor output waveform when extrapolation is used to calculate the control value according to an embodiment. Detailed Implementation

[0042] In the following, some embodiments of the present disclosure are described in detail with reference to the accompanying drawings. Furthermore, the same reference numerals are assigned to the same components even when the components are shown in different drawings. In addition, detailed descriptions of well-known configurations or functions have been omitted in the description of the present disclosure to avoid obscuring its main points.

[0043] Furthermore, terms such as “first,” “second,” “A,” “B,” “(a),” “(b),” etc., may be used to describe components of this disclosure. These terms are used only to distinguish the corresponding component from other components, and the nature, order, or sequence of the corresponding components are not limited by these terms. Where a component is described as “coupled,” “combined,” or “connected” to another component, it should be understood that the corresponding component may be directly coupled or connected to the other component, or the corresponding component may also be “coupled,” “combined,” or “connected” to the component through another component disposed therebetween.

[0044] Figure 1 This is a configuration diagram of the electric motor device according to the embodiment.

[0045] See Figure 1 The motor device 100 may include a motor 130, a motor controller 120, and a rotary transformer 110.

[0046] The motor 130 can be a permanent magnet synchronous motor.

[0047] A permanent magnet synchronous motor (PMSM) is an electric motor that offers high efficiency and excellent performance, and is widely used in various fields such as environmentally friendly vehicles, industrial machinery, and household appliances. A PMSM consists of a stator and a rotor. The stator has armature windings, while the rotor has permanent magnets. The motor operates through electromagnetic interaction and is suitable for precise position control and high-speed operation.

[0048] The PMSM operates by having the rotor rotate synchronously with the stator's rotating magnetic field. When alternating current (AC) is applied to the windings in the stator, a rotating magnetic field is generated. This magnetic field interacts with the permanent magnets in the rotor, causing the rotor to rotate. During this process, the rotor rotates at a speed synchronized with the stator's magnetic field. As a result, even under varying load conditions, the PMSM can maintain a constant speed with minimal variation.

[0049] PMSMs offer high energy efficiency. Because they utilize permanent magnets, they can generate a magnetic field without requiring an external power supply, which helps reduce energy loss and improve efficiency. Furthermore, PMSMs offer high torque density and are compact and lightweight. These characteristics are crucial in transportation applications such as electric vehicles.

[0050] PMSMs provide high-precision control. They are widely used in applications requiring precise motion control because they can accurately control position and speed. For this purpose, position detectors such as the rotary transformer 110 are employed, and these devices sense the precise position of the rotor and provide feedback to the control system.

[0051] The motor controller 120 is an electronic device for controlling and optimizing the operation of the motor 130. By controlling the motor's speed, position, and torque, it enables efficient and precise operation of the motor in various applications.

[0052] The motor controller 120 includes a microcontroller unit (MCU) or a digital signal processor (DSP). It receives input signals from various sensors to monitor the state of the motor 130 and generates control signals. For example, the motor controller 120 reads position sensing values ​​or speed sensing values ​​from the resolver 110 and generates control signals based on these values ​​to control the speed or position of the motor 130.

[0053] The power conversion device can be integrated into the motor 130 or the motor controller 120. The power conversion device adjusts the voltage and current according to the control signal generated by the motor controller 120, thereby controlling the speed and torque of the motor 130.

[0054] The rotary transformer 110 can calculate the position, speed, and rotation angle of the motor 130. In addition, the rotary transformer 110 can transmit the calculated values ​​to the motor controller 120.

[0055] Figure 2 This is a configuration diagram of a rotary transformer according to an embodiment.

[0056] See Figure 2 The rotary transformer 110 may include a rotor winding 210, a first stator winding 220, a second stator winding 230, and a rotary transformer calculator 240.

[0057] The rotor winding 210 can be positioned on the rotating shaft of the motor. The rotor winding 210 can rotate together with the rotor of the motor at the same speed as the motor rotor or at a speed that is reduced or increased by a certain ratio.

[0058] The excitation voltage Ur can be supplied to the rotor winding 210. The excitation voltage Ur is an alternating voltage that can generate a changing electromagnetic field in the rotor winding 210. When the rotor winding 210 rotates, the electromagnetic field also rotates accordingly.

[0059] The first stator winding 220 can be a fixed coil. Due to the electromagnetic field generated in the rotor winding 210, a first induced voltage Ucos can be generated in the first stator winding 220. The first induced voltage Ucos can be in the form of an alternating voltage, and this voltage can be defined as a cosine voltage.

[0060] The second stator winding 230 can be a fixed coil. Due to the electromagnetic field generated in the rotor winding 210, a second induced voltage Usin can be generated in the second stator winding 230. The second induced voltage Usin can be in the form of an alternating voltage, and this voltage can be defined as a sinusoidal voltage.

[0061] The first stator winding 220 and the second stator winding 230 can be arranged such that their magnetic fields are orthogonal to each other. With this arrangement, the first induced voltage Ucos can be defined as a cosine voltage, while the second induced voltage Usin can take the form of a sine voltage with a waveform having a 90-degree phase difference relative to the first induced voltage Ucos.

[0062] The rotary transformer calculator 240 uses an ADC (analog-to-digital converter) to generate voltage sensing values ​​of a first induced voltage Ucos and a second induced voltage Usin, and calculates the position, speed and rotation angle of the motor based on the voltage sensing values.

[0063] The resolver calculator 240 can use trigonometric functions to calculate the position, speed, and rotation angle of a motor. The resolver calculator 240 may include ATO (Angle Tracking Observer) logic and calculates the motor's position, speed, and rotation angle based on the ATO logic.

[0064] The excitation voltage Ur is provided to the rotor winding 210 according to the excitation PWM (pulse width modulation) signal. The rotary transformer calculator 240 can sense the first induced voltage Ucos and the second induced voltage Usin according to the sensing PWM signal that lags behind the excitation PWM signal by a certain amount of time.

[0065] Figure 3 This is a view showing the main waveforms of a rotary transformer according to an embodiment.

[0066] See Figure 3 When the rotary transformer starts operating, it can generate an excitation PWM signal PWMr with a given offset time (start-up offset).

[0067] A rotary transformer can also generate an excitation voltage Ur in sync with the period Pr of the excitation PWM signal PWMr. The excitation voltage Ur can be an AC voltage in the form of a sinusoidal waveform.

[0068] Alternatively, the sensing PWM signal PWMs can be generated several cycles Pr after the excitation PWM signal PWMr is generated. The resolver can use a specific time offset (trigger start offset) to generate the sensing PWM signal PWM. The sensing PWM signal PWMs can be generated several cycles Pr later than the excitation PWM signal PWMr.

[0069] The period of the sensing PWM signal PWM2 can have the same length as the period of the excitation PWM signal PWMr. However, there may be a certain phase difference (delay) between the sensing PWM signal PWM2 and the excitation PWM signal PWMr. The peak values ​​of the first induced voltage Ucos and the second induced voltage Usin induced by the excitation voltage Ur are not aligned with the rising edge of the excitation PWM signal PWMr, but appear after a certain delay. In order to sense the peak values ​​of the first induced voltage Ucos and the second induced voltage Usin, a resolver can generate the sensing PWM signal PWMs after a certain time delay.

[0070] The excitation PWM signal PWMr can provide a reference for the excitation voltage Ur used in the resolver. The resolver can generate the excitation voltage Ur based on the excitation PWM signal PWMr. Simultaneously, the sensing PWM signal PWM can provide a reference for the sensing timing of the induced voltages Ucos and Usin in the stator windings. The resolver can sense the induced voltages Ucos and Usin at the rising edge of the sensing PWM signal PWM using an ADC.

[0071] A resolver can calculate the position, speed, and rotation angle of a motor using sensed induced voltages Ucos and Usin. In this case, the resolver can calculate the motor's position, speed, and rotation angle based on a sensed PWM signal.

[0072] There may be a time difference between the timing of the sensing PWM signals PWMs and the timing of the motor controller performing control using the sensed values ​​(position, speed, rotation angle, etc.). Such a time difference can be caused by several factors. For example, if the motor controller performs control with the same period as the excitation PWM signal PWMr, the aforementioned time difference may occur because its phase position is between the excitation PWM signal PWMr and the sensing PWM signals PWMs. Furthermore, the aforementioned time difference can be generated when the resolver generates the sensed values ​​(position, speed, rotation angle, etc.) during a first time period and when the motor controller controls the motor during a second time period different from the first time period.

[0073] If a time difference occurs between the sensing timing and the control timing, control instability factors such as torque ripple may occur.

[0074] As previously mentioned, the resolver calculates the motor's rotation angle based on the voltage sensed values ​​Ucos and Usin from the stator windings. However, a time difference may exist between the resolver's control timing and the voltage sensing timing. Therefore, the motor controller can recalculate the rotation angle used for control by checking for this time difference and extrapolating the rotation angle calculated by the resolver. The motor controller can then control the motor using this control angle.

[0075] Figure 4 This is a configuration diagram of a motor controller according to an implementation method.

[0076] Reference Figure 4 The motor controller 120 may include a rotary transformer signal processing unit 410, a control value calculation unit 420, and a control signal output unit 430.

[0077] The resolver signal processing unit 410 can obtain the motor's rotation angle and the resolver's sensing timing from the resolver. The rotation angle and sensing timing can be obtained using shared memory or via communication.

[0078] The control value calculation unit 420 can calculate the rotation angle for control by checking the control timing for motor control and extrapolating the rotation angle calculated by the rotary transformer based on the time difference between the control timing and the sensing timing.

[0079] Furthermore, the control value calculation unit 420 can determine the control value for the motor by using the rotation angle used for control.

[0080] In addition, the control signal output unit 430 can output a control signal corresponding to a determined control value to the motor.

[0081] The motor controller 120 may further include an ADC for sensing control values ​​of the motor. The motor controller 120 can sense the voltage or current of the power conversion device supplying power to the motor using the ADC.

[0082] The control value calculation unit 420 can check the sensing timing of the ADC based on the above control timing.

[0083] Figure 5 This is a view showing the main waveforms of the motor controller and the rotary transformer according to the embodiment.

[0084] See Figure 5 It can generate a control PWM signal PWMmc used to determine the control period.

[0085] The motor controller can generate a control PWM signal PWMmc during the first control period Ta1, Ta2 and Ta3.

[0086] Furthermore, a control ADC signal PwMma can be generated with the same duration as the control PWM signal PWMmc. The motor controller can sense the required control value based on the control ADC signal PWMma. Additionally, the motor controller can determine the control timing based on the control ADC signal PWMma.

[0087] Based on the control ADC signal PWMma, the interrupt service routine (ISRm) of the motor controller can be invoked. Furthermore, the motor controller's ISR (ISRm) can calculate the control values ​​used to control the motor.

[0088] The motor controller can calculate the control values ​​for controlling the motor by using the motor's position, speed, and rotation angle calculated by a resolver.

[0089] A resolver can generate an excitation PWM signal PWMr and a sensing PWM signal PWMs. The resolver can generate the excitation PWM signal PWMr and the sensing PWM signal PWMs so that they have the same control periods Ta1, Ta2, and Ta3 as the control PWM signal PWMmc generated by the motor controller. In this case, the control PWM signal PWMmc, the excitation PWM signal PWMr, and the sensing PWM signal PWMs can have a phase difference D1.

[0090] The ISR (ISRr) of the resolver can be invoked based on the sensed PWM signals PWMs. Furthermore, the ISR (ISRr) of the resolver can calculate the position, speed, and rotation angle of the motor.

[0091] However, time differences D2, D3, and D4 may exist between the timing of the activation of the resolver ISR (ISRr) and the motor controller ISR (ISRm). As mentioned earlier, these time differences D2, D3, and D4 may occur due to the phase difference between the control PWM signal PWMmc, the excitation PWM signal PWMr, and the sensing PWM signal PWMs.

[0092] These time differences, D2, D3, and D4, can lead to torque ripple and control instability.

[0093] Simultaneously, the motor controller can change the control period. The motor controller can change the control period from the first period Ta1 and Ta2 to the second period Tb1 and Tb2. In this case, since the resolver does not change its period, the time difference between the timing of the call to the resolver ISR (ISRr) and the motor controller ISR (ISRm) can become larger. For example, the time difference D4 observed in the second control period Tb1 and Tb2 can be greater than the time difference D2 observed in the first control period Ta1 and Ta2.

[0094] In this way, the resolver can generate a voltage sensing value in a first time period (e.g., a first control time period), while the motor controller can control the motor in a second time period (e.g., a second control time period). Here, the first time period can be formed based on the sensed PWM signal PWMs, and the second time period can be formed based on the control ADC signal PWMma.

[0095] The motor controller can control the motor by changing the second time period. Therefore, during the first time interval (e.g., Ta1 and Ta2), the first and second time periods can have the same duration, and during the second time interval (e.g., Tb1 and Tb2), the first and second time periods can have different durations.

[0096] To address the problems caused by these time differences, the motor controller can extrapolate values ​​obtained from the rotary transformer.

[0097] Figure 6 This is a view illustrating the extrapolation process according to an implementation method.

[0098] refer to Figure 6 The motor controller can extrapolate the sensed values ​​calculated by the rotary transformer based on time.

[0099] The motor controller can check the currently acquired resolver sensing value y2 and resolver sensing timing x2.

[0100] Furthermore, the motor controller can check the previously acquired and stored resolver sensing value y1 and resolver sensing timing x1.

[0101] Furthermore, the motor controller can calculate the control sensing value y3 to be used at the current control timing x3 using an extrapolation method, as shown in mathematical expression 1:

[0102] [Mathematical Expression 1]

[0103] dy2 = dx2(dy1 / dx1)

[0104] y3 = y2 + dy2

[0105] dx2 = x3 - x2, dy1 = y2 - y1, dx1 = x2 - x1

[0106] y3 = y2 + (x3 - x2) (y2 - y1) / (x2 - x1)

[0107] Figure 7 This is a flowchart of a motor control method according to an implementation method.

[0108] See Figure 7 The motor controller can check the control timing (S700).

[0109] Furthermore, the motor controller can obtain the motor's rotation angle and the transformer's sensing timing from the rotary transformer (S702).

[0110] The motor controller can calculate the rotation angle for control by extrapolating the rotation angle calculated by the rotary transformer based on the time difference between the control timing and the sensing timing of the rotary transformer (S704).

[0111] Then, the motor controller can determine the control value of the motor by using the rotation angle used for control (S706).

[0112] Then, the motor controller can output a control signal to the motor according to the control value (S708).

[0113] At any given time, the sensing period of the rotary transformer and the control period of the motor can have different durations.

[0114] In addition, the control period can be varied.

[0115] Figure 8 This is a view showing the motor output waveform when the control value is calculated without extrapolation.

[0116] As from Figure 8 It can be seen that when extrapolation is not applied, a very large ripple (492 rpm) is measured corresponding to the difference between the maximum measured value of the motor output (892 rpm) and the minimum measured value of the motor output (400 rpm).

[0117] Figure 9 This is a view showing the motor output waveform when extrapolation is used to calculate the control value according to an embodiment.

[0118] like Figure 9 As shown, when extrapolation is applied, a very small ripple (12 rpm) is measured, corresponding to the difference between the maximum measured value of the motor output (637 rpm) and the minimum measured value of the motor output (625 rpm).

[0119] As described above, according to this disclosure, the rotation angle of the motor detected during control timing can be made more similar to the actual rotation angle of the motor. Furthermore, according to this disclosure, the stability of motor control can be enhanced, and torque ripple in the motor can be minimized.

[0120] As used herein, the terms “comprising,” “including,” or “having” mean, unless otherwise specified, that they may include corresponding components and should therefore be interpreted as including other components rather than excluding them. Unless otherwise defined, all terms including technical or scientific terms have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. Commonly used terms, such as those defined in dictionaries, should be interpreted as consistent with their meaning in the context of the relevant field and should not be interpreted in an ideal or overly formal sense unless expressly defined herein.

[0121] The above description is merely an illustrative description of the technical concept of this disclosure, and those skilled in the art will understand that various modifications and variations can be made without departing from the essential characteristics of this disclosure. Therefore, the embodiments disclosed in this disclosure are not intended to limit the technical concept of this disclosure, but rather to interpret it, and the scope of the technical concept of this disclosure is not limited by these embodiments. The scope of protection of this disclosure should be interpreted by the appended claims, and all technical concepts within the scope equivalent to those claims should be interpreted as being included within the scope of the rights of this disclosure.

Claims

1. A motor control device comprising: a resolver that calculates a rotation angle of a motor from a voltage sense value from a stator winding; and a motor controller that calculates a rotation angle for control by extrapolating the rotation angle calculated by the resolver based on a time difference between a control timing of the resolver and a voltage sense timing, and controls the motor by using the rotation angle for control.

2. The motor control device according to claim 1, wherein The resolver generates the voltage sense value in a first period, and the motor controller controls the motor in a second period.

3. The motor control device according to claim 2, wherein The resolver generates the voltage sense value in the first period according to a first pulse width modulation signal, and the motor controller controls the motor in the second period according to a second pulse width modulation signal different from the first pulse width modulation signal.

4. The motor control device according to claim 2, wherein The motor controller controls the motor by changing the second period.

5. The motor control device of claim 2, wherein, The first period and the second period have the same duration during a first time interval, and the first period and the second period have different durations during a second time interval.

6. The motor control device of claim 1, wherein, The resolver includes: a rotor winding located on a rotation axis of the motor; a first stator winding in which a first induced voltage is generated by an electromagnetic field formed in the rotor winding; a second stator winding in which a second induced voltage is generated by an electromagnetic field formed in the rotor winding; and a resolver calculator that generates voltage sense values for the first induced voltage and the second induced voltage by using an analog-to-digital converter, and calculates a rotation angle of the motor from the voltage sense values.

7. The electric motor control device of claim 6, wherein, An excitation voltage is supplied to the rotor winding according to an excitation pulse width modulation signal, the resolver calculator senses the first induced voltage and the second induced voltage according to a sense pulse width modulation signal that lags the excitation pulse width modulation signal by a certain time.

8. The electric motor control device of claim 6, wherein, The first stator winding and the second stator winding are arranged so that magnetic fields of the first stator winding and the second stator winding are orthogonal to each other.

9. The electric motor control device of claim 6, wherein, The resolver calculator includes angle tracking observer logic, and calculates a rotation angle of the motor according to the angle tracking observer logic.

10. A motor controller comprising: a resolver signal processing unit that obtains a rotation angle of a motor and a sense timing of a resolver from the resolver; a control value calculation unit that calculates a rotation angle for control by extrapolating a rotation angle calculated by a resolver by checking a control timing and based on a time difference between the control timing of the resolver and the sense timing, and determines a control value for the motor by using the rotation angle for control; and a control signal output unit that outputs a control signal corresponding to the control value for the motor.

11. The motor controller according to claim 10, further comprising an analog-to-digital converter that senses the control value for the motor, wherein, The control value calculation unit checks a sensing timing of the analog-digital converter based on the control timing.

12. The motor controller of claim 10, wherein, At a point in time, a sensing period of the resolver and a control period of the control value calculation unit have different durations.

13. The motor controller of claim 12, wherein, The control period of the control value calculation unit is variable.

14. The motor controller of claim 10, wherein, An excitation pulse width modulation signal provides a reference for an excitation voltage of the resolver, a sensing pulse width modulation signal provides a reference for a sensing timing of an induced voltage of the stator winding of the excitation voltage, the excitation pulse width modulation signal and the sensing pulse width modulation signal having a phase difference therebetween.

15. The motor controller of claim 14, wherein, The stator winding is arranged to have magnetic fields of the stator winding orthogonal to each other.

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