KR20110118502A - Method for estimating rotar position of synchronous motor and motor driver using the same - Google Patents

Abstract

The present invention relates to a method for estimating the position of a synchronous motor and a motor driving apparatus using the same. The motor drive apparatus according to the embodiment of the present invention includes an output current detection unit for detecting a three-phase output current flowing to the synchronous motor, an axis conversion unit for converting the three-phase output current to a two-phase current of the stationary coordinate system, and a two-phase of the stationary coordinate system. And a position estimating unit for estimating the rotor position of the synchronous motor based on the current. As a result, the position estimation of the synchronous motor can be easily performed without the position sensing unit.

Description

Method for estimating the position of a synchronous motor and a motor driving device using the same {Method for estimating rotar position of synchronous motor and motor driver using the same}

The present invention relates to a method for estimating a position of a synchronous motor and a motor driving apparatus using the same, and more particularly, to a position estimating method for a synchronous motor capable of easily performing position estimation of a synchronous motor without a position sensing unit and a motor driving apparatus using the same. It is about.

Recently, various methods for efficient power consumption in home appliances have been devised in consideration of environmental problems. Accordingly, the use of synchronous motors (SM), in particular, permanent magnet synchronous motors (PMSM) to which permanent magnets are applied, is increasing.

Such a synchronous motor includes a stator and a rotor, among which a rotor or a stator includes a permanent magnet. On the other hand, for accurate position sensing (postion sensing) of the rotor of the synchronous motor, a position sensor such as a rotary encoder or a resolver is used.

However, the case where such a position sensing part is difficult to use because of high cost or environmental or mechanical reasons is increasing.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for estimating a position of a synchronous motor, which can easily perform a position estimation of a synchronous motor without a position sensing unit, and a motor driving apparatus using the same.

Another object of the present invention is to provide a method for estimating a position of a synchronous motor which can easily perform position estimation in another synchronous motor, and a motor driving apparatus using the same.

The motor drive apparatus according to the embodiment of the present invention for achieving the above object, the output current detection unit for detecting the three-phase output current flowing to the synchronous motor, the axis conversion unit for converting the three-phase output current to the two-phase current of the stationary coordinate system and And a position estimating unit for estimating the rotor position of the synchronous motor based on the two-phase current of the stationary coordinate system.

In addition, the method for estimating the position of a synchronous motor according to an embodiment of the present invention for achieving the above object, detecting the three-phase output current flowing in the synchronous motor, and converting the three-phase output current into a two-phase current of the stationary coordinate system And estimating the rotor position of the synchronous motor based on the two-phase current of the stationary coordinate system.

According to one embodiment of the present invention, it is possible to simply perform the position estimation in the synchronous motor by using the magnetic flux observer in the stationary coordinate system without the position sensor. In particular, this position estimation method can be obtained simply and easily because only two motor parameters, specifically, phase resistance Rs and q-axis inductance Lq, are required.

In addition, only the proportional constant is changed according to the type of the synchronous motor, and the same operation may be performed. This can be used in common.

1 is a circuit diagram showing an example of a motor driving apparatus according to an embodiment of the present invention.
FIG. 2 is an internal block diagram of the controller of FIG. 1.
3 is an internal block diagram of the position estimator of FIG. 2.
4 is a diagram illustrating a relationship between a synchronous coordinate system and a still coordinate system.
5 is a flowchart illustrating a method of estimating a position of a synchronous motor according to an exemplary embodiment of the present invention.

Hereinafter, with reference to the drawings will be described the present invention in more detail.

The suffixes "module" and "unit" for components used in the following description are merely given in consideration of ease of preparation of the present specification, and do not impart any particular meaning or role by themselves. Therefore, the "module" and "unit" may be used interchangeably.

In a synchronous motor (SM), a method of determining a rotor position of a motor without a postion sensor may be performed by using, for example, voltage information and current information of the motor. To estimate the location. Since there is no position sensor, this is also called a sensorless method.

However, the sensorless method has a problem that it is difficult to implement it in a low-performance microcomputer or microprocessor because the computation algorithm is complicated and the computation amount is large.

In particular, this sensorless method requires a significant amount of motor paramater. Examples of motor parameters include stator resistance (Rs), d-axis inductance (Ld), which is a magnetic flux inductance, q-axis inductance (Lq), which is a torque inductance, and a back-emf constant. The motor parameters described above are used when performing position estimation in a rotating reference frame.

Embodiments of the present invention present a simple sensorless method for a synchronous motor (SM) using a flux observer in a stationary reference frame. That is, the embodiment of the present invention proposes a method of simply estimating the rotor position in flux linkage (λ). Hereinafter, an electric motor drive device for driving a synchronous motor will be described.

1 is a circuit diagram showing an example of a motor driving apparatus according to an embodiment of the present invention.

Referring to the drawings, according to an embodiment of the present invention, the motor driving apparatus 100 of FIG. 1 includes a converter 110, an inverter 120, a controller 130, a dc terminal voltage detector B, and a smoothing capacitor. (C), and an output current detector (E). In addition, the motor driving apparatus 100 of FIG. 1 may further include an input current detector A, reactors L1, L2, and the like.

The reactors L1 and L2 are disposed between the commercial AC power supply 105, v _s and the converter 110 to perform power factor correction or boost operation. In addition, the reactors L1 and L2 may perform a function of limiting harmonic currents caused by the fast switching of the converter 110.

The input current detector A can detect the input current i _s input from the commercial AC power supply 105. To this end, a CT (current trnasformer), a shunt resistor, or the like may be used as the input current detector A. FIG. The detected input current i _s is a discrete signal in the form of a pulse and may be input to the controller 130 to generate the converter switching control signal Scc or to estimate the input voltage v _s . .

The converter 110 converts the commercial AC power supply 105 which passed through the reactors L1 and L2 into a DC power supply and outputs the DC power. Although the commercial AC power supply 105 is shown as a single phase AC power supply in the figure, it may be a three phase AC power supply. The internal structure of the converter 110 also varies according to the type of the commercial AC power supply 105.

For example, in the case of a single phase AC power supply, a half bridge type converter in which two switching elements and four diodes are connected may be used, and in the case of a three phase AC power supply, six switching elements and six diodes may be used.

When the converter 110 includes a switching element, the boosting operation, power factor improvement, and DC power conversion may be performed by the switching operation of the switching element.

On the other hand, the converter 110 may be made of a diode or the like without a switching element, and may perform rectification without a separate switching operation.

The smoothing capacitor C smoothes and stores the input power. In the figure, one element is illustrated as the smoothing capacitor C, but a plurality of elements may be provided to ensure device stability.

On the other hand, in the drawing, but is illustrated as being connected to the output terminal of the converter 110, not limited to this, a direct current power source may be input directly, for example, a direct current power source from a solar cell to the smoothing capacitor (C). It may be input directly or DC / DC converted. Hereinafter, the parts illustrated in the drawings will be mainly described.

On the other hand, since the DC power is stored at both ends of the smoothing capacitor C, this may be referred to as a dc terminal or a dc link terminal.

The dc end voltage detector B may detect a dc end voltage Vdc that is both ends of the smoothing capacitor C. To this end, the dc terminal voltage detector B may include a resistor, an amplifier, and the like. The detected dc terminal voltage Vdc is a discrete signal in the form of a pulse and may be input to the controller 130 to generate the converter switching control signal Scc.

The inverter 120 includes a plurality of inverter switching elements, converts the smoothed DC power supply Vdc into three-phase AC power supplies va, vb, vc of a predetermined frequency by the on / off operation of the switching device, It can output to the synchronous motor 150.

Inverter 120 has a pair of upper arm switching elements Sa, Sb, Sc and lower arm switching elements S'a, S'b, S'c, which are connected in series with each other, and a total of three pairs of upper and lower arms The switching elements are connected in parallel with each other (Sa & S'a, Sb & S'b, Sc & S'c). Diodes are connected in anti-parallel to each of the switching elements Sa, S'a, Sb, S'b, Sc, and S'c.

The switching elements in the inverter 120 perform on / off operations of the respective switching elements based on the inverter switching control signal Sic from the controller 130. As a result, three-phase AC power supplies va, vb and vc having a predetermined frequency are output to the three-phase synchronous motor 150.

The controller 130 may control the switching operation of the inverter 120. To this end, the controller 130 may receive an output current i _o detected by the output current detector E. FIG.

The controller 130 outputs an inverter switching control signal Sic to the inverter 120 in order to control the switching operation of the inverter 120. The inverter switching control signal Sic is a PWM switching control signal, which is generated and output based on the output current value i _o detected by the output current detector E. FIG. Detailed operation of the output of the inverter switching control signal (Sic) in the control unit 130 will be described later with reference to FIG.

The output current detection unit E detects the output current i _o flowing between the inverter 120 and the three-phase synchronous motor 150. That is, the current flowing through the synchronous motor 150 is detected. The output current detector E may detect all of the output currents ia, ib, and ic of each phase, or may detect the output currents of two phases by using three-phase equilibrium.

The output current detector E may be located between the inverter 120 and the synchronous motor 150, and a current trnasformer (CT), a shunt resistor, or the like may be used for current detection.

When a shunt resistor is used, three shunt resistors are located between the inverter 120 and the synchronous motor 150 or the three lower arm switching elements S'a, S'b, S'c of the inverter 120. It is possible to connect one end to each). On the other hand, it is also possible to use two shunt resistors using three-phase equilibrium. On the other hand, when one shunt resistor is used, the corresponding shunt resistor may be disposed between the above-described capacitor C and the inverter 120.

The detected output current i _o may be applied to the controller 130 as a discrete signal in the form of a pulse, and the inverter switching control signal Sic is generated based on the detected output current io. do. Hereinafter, it will be described that the detected output current (i _o ) is the three-phase output current (ia, ib, ic).

On the other hand, the three-phase synchronous motor 150 includes a stator and a rotor, and an alternating current power of each phase of a predetermined frequency is applied to the coils of the stators of the phases (a, b, and c phases). It turns.

Such a synchronous motor 150 may include, for example, a Surface-Mounted Permanent-Magnet Synchronous Motor (SMPMSM), an Interior Permanent Magnet Synchronous Motor (IPMSM), and a synchronous motor. Synchronous Reluctance Motor (Synrm) and the like.

Of these, SMPMSM and IPMSM are permanent magnet synchronous motors (PMSMs) with permanent magnets, and synrms have no permanent magnets. Structural features and related details of each of these motors will be described later.

On the other hand, when the converter 110 includes a switch element, the controller 130 may control the switching operation of the switching element in the converter 110. To this end, the controller 130 may receive an input current i _s detected by the input current detector A. In addition, the controller 130 may output the converter switching control signal Scc to the converter 110 in order to control the switching operation of the converter 110. The converter switching control signal Scc is a PWM switching control signal and may be generated and output based on the input current i _s detected from the input current detector A. FIG.

2 is an internal block diagram of the controller of FIG. 1, FIG. 3 is an internal block diagram of the position estimator of FIG. 2, and FIG. 4 is a diagram illustrating a relationship between a synchronous coordinate system and a still coordinate system.

First, referring to FIG. 2, the controller 130 may include an axis converter 210, a position estimator 220, a current command generator 230, a voltage command generator 240, and an axis converter 250. , And a switching control signal output unit 260.

The axis conversion unit 210 receives the three-phase output currents (ia, ib, ic) detected by the output current detection unit E, and converts the two-phase currents i α and i β of the stationary coordinate system.

Referring to FIG. 4, the axis conversion unit 210 may convert the three-phase coordinate system of FIG. 4A into a two-phase (αβ) stationary coordinate system of FIG. 4B. To this end, Equation 1 below may be used.

Here, ia, ib, ic three-phase output current represents va, vb, vc three-phase output voltage, i (alpha), i (beta) shows the two-phase current in a static coordinate system, and v (alpha), v (beta) shows the two phase voltage in a static coordinate system.

On the other hand, the axis conversion unit 210 can convert the two-phase current (iα, iβ) of the stationary coordinate system into the two-phase current (id, iq) of the rotary coordinate system. To this end, Equation 2 below may be used.

Here, id, iq represents d-axis current and q-axis current, and vd and vq represent d-axis voltage and q-axis voltage. On the other hand, θ of sinθ and cosθ represents the rotor position. This rotor position can be estimated simply from the position estimation unit 220 to be described later.

Next, the position estimating unit 220 receives the two-phase currents iα and iβ of the stationary coordinate system and the two-phase voltages vα and vβ of the stationary coordinate system, and estimates the rotor position θ.

At this time, the two-phase currents iα and iβ of the stationary coordinate system may be input from the axis converting unit 210, and the two-phase voltages vα and vβ of the stationary coordinate system are dc from the dc stage voltage detector B. It may be calculated in consideration of the voltage Vdc and the switching operation state of the inverter 120. For example, the three-phase output voltages (va, vb, vc) are calculated according to a predetermined relation according to the dc stage voltage (Vdc) from the c stage voltage detector (B) and the switching operation state of the inverter (120). In addition, the axis transformation unit 210 may be converted back to the two-phase voltage (vα, vβ) of the still coordinate system.

)와 추정된 속도(

)를 출력할 수 있다.Meanwhile, as illustrated in FIG. 3, the position estimator 220 may include a magnetic flux observer 310 and a position calculator 320. And the estimated position (

) And estimated speed (

) Can be printed.

Operations in the magnetic flux observer 310 and the position calculator 320 in the position estimator 220 will be described in detail with reference to Equation 5 below.

)와 속도 지령치(ω^* _r)에 기초하여, 전류 지령치(i^* _q)를 생성한다. 예를 들어, 전류 지령 생성부(230)는, 추정 속도(

)와 속도 지령치(ω^* _r)의 차이에 기초하여, PI 제어기(235)에서 PI 제어를 수행하며, 전류 지령치(i^* _q)를 생성할 수 있다. 도면에서는, 전류 지령치로, q축 전류 지령치(i^* _q)를 예시하나, 도면과 달리, d축 전류 지령치(i^* _d)를 함께 생성하는 것도 가능하다. 한편, d축 전류 지령치(i^* _d)의 값은 0으로 설정될 수도 있다. On the other hand, the current command generation unit 230 is estimated speed (

) And the current command value i ^* _q based on the speed command value ω ^* _r . For example, the current command generation unit 230 is estimated speed (

) Based on the difference between the speed command value ω ^* _r and the PI controller 235, the PI control may be performed, and the current command value i ^* _q may be generated. In the drawing, although the q-axis current command value i ^* _q is illustrated as a current command value, it is also possible to generate | generate a d-axis current command value i ^* _d unlike a figure. On the other hand, the value of the d-axis current command value i ^* _d may be set to zero.

On the other hand, the current command generation unit 230 may further include a limiter (not shown) for restricting the level so that the current command value i ^* _q does not exceed the allowable range.

Next, the voltage command generation unit 240 includes the d-axis and q-axis currents i _d and i _q which are axis-converted in the two-phase rotational coordinate system by the axis conversion unit, and the current command value in the current command generation unit 230 and the like. Based on i ^* _d , i ^* _q ), the d-axis and q-axis voltage command values v ^* _d and v ^* _q are generated. For example, the voltage command generation unit 240 performs PI control in the PI controller 244 based on the difference between the q-axis current i _q and the q-axis current command value i ^* _q , and q The axial voltage setpoint v ^* _q can be generated. In addition, the voltage command generation unit 240 performs PI control in the PI controller 248 based on the difference between the d-axis current i _d and the d-axis current command value i ^* _d , and the d-axis voltage. The setpoint (v ^* _d ) can be generated. On the other hand, the voltage command generation unit 240 may further include a limiter (not shown) for restricting the level so that the d-axis and q-axis voltage command values (v ^* _d , v ^* _q ) do not exceed the allowable range. .

On the other hand, the generated d-axis and q-axis voltage command values v ^* _d and v ^* _q are input to the axis conversion unit 250.

)와, d축, q축 전압 지령치(v^* _d,v^* _q)를 입력받아, 축변환을 수행한다.The axis transform unit 250 is a position estimated by the position estimator 220 (

), And the d-axis and q-axis voltage command values (v ^* _d , v ^* _q ) are input, and axis conversion is performed.

)가 사용될 수 있다.First, a transformation is performed from a two-phase rotation coordinate system to a two-phase stop coordinate system. To this end, Equation 3 below may be used. At this time, the position estimated by the position estimating unit 220 (

) Can be used.

Then, the conversion is performed from the two-phase stop coordinate system to the three-phase stop coordinate system. To this end, Equation 4 below may be used.

Through this conversion, the axis conversion unit 150 outputs the three-phase output voltage command value (v ^* a, v ^* b, v ^* c).

The switching control signal output unit 260 generates and outputs an inverter switching control signal Sic, which is a PWM signal, based on the three-phase output voltage command values v ^* a, v ^* b, v ^* c. The output inverter switching control signal Sic may be converted into a gate driving signal by a gate driver (not shown) and input to a gate of each switching element in the inverter 120. As a result, each of the switching elements Sa, S'a, Sb, S'b, Sc, and S'c in the inverter 120 performs a switching operation.

On the other hand, the operation of the position estimation unit 220 described above will be described in detail below.

The electrical models in the rotation coordinate systems d and q axes of the synchronous motor SM are as shown in Equations 5 and 6 below.

Where λd and λq are the d-axis and q-axis linkage fluxes, vd and vq are the d-axis and q-axis voltages, id and iq are the d-axis and q-axis currents, respectively, and Rs is the phase resistance ( stator resistor).

Here, Ld and Lq represent d-axis and q-axis inductance, respectively, and λpm represents magnet flux linkage by a magnet.

That is, Equation 5 shows the relationship between the change rate of the linkage magnetic flux in the rotational coordinate systems d and q axes, and the d, q-axis voltage and the like, and Equation 6 represents the linkage flux and the d-axis in the rotational coordinate systems d and q axes. The relationship with the q-axis current is shown.

On the other hand, the relationship between the stationary coordinate system (α, β axis) and the rotational coordinate system (d axis, q axis) of the synchronous motor (IPMSM) to which the permanent magnet is applied is as shown in Equations 7 and 8 below.

Where θ r is the position of the rotor, λ α and λ β are the α and β axis linkage fluxes, v α and v β are the α and β axis voltages, i α and i β are the α and β axes, respectively. Indicates current.

On the other hand, the equation (7) is based on the relationship between the static coordinate system (α, β axis) and the rotation coordinate system (d-axis, q-axis), the rate of change of the d-axis, q-axis chain link magnetic flux of the rotation coordinate system and the α axis of the static coordinate system What is represented by (beta) -axis voltage, (alpha) -axis, (beta) -axis current, and (alpha)-and (beta) -axis chain | strand bridge magnetic flux is illustrated.

On the other hand, Equation (8) shows that, unlike the rotational coordinate system, the rate of change in the α-axis and β-axis linkage fluxes of the stationary coordinate system is not related to the linkage flux (λpm) by the magnet.

Next, when the contents of the above-described formula (6) and the formula (7) are combined, they are arranged as shown in the following formulas (9) and (10).

In particular, Equation 10 is summarized using Equation 9, trigonometric properties, and the like (for example, cos ² θ + sin ² θ = 1 and the like).

Accordingly, in the equation (10), the α-axis and β-axis magnetic flux linkages (λα, λβ) of the stationary coordinate system are α-axis, β-axis currents (iα, iβ), d-axis, q-axis inductance (Ld, Lq), d It can be expressed by the axial current id, the linkage magnetic flux λpm by the magnet, and the position θr of the rotor.

On the other hand, if Equation (10) is rearranged based on the position (θr) of the rotor, Equation 11 is as follows.

Here, K is a proportional constant and may be expressed by an equation regarding d-axis, q-axis inductance (Ld, Lq), d-axis current (id), and the linkage magnetic flux (λpm) by the magnet.

As a result, the position θr of the rotor can be estimated through the α-axis and β-axis flux linkages (λα, λβ) and α-axis, β-axis currents iα, iβ if the proportional constant K is a predetermined value. It can be seen that.

The magnetic flux estimation through the magnetic flux observer 310 in the position estimator 220 may be expressed by the following Equation 12 based on Equation 8 described above.

와

는, 추정된 쇄교 자속을 나타낸다.g는 센서리스 파라미터로서, 소정값을 나타낸다.here,

Wow

Represents an estimated linkage flux. G is a sensorless parameter and represents a predetermined value.

,

)을 이용하여, 위치 추정부(220) 내의 위치 연산부(320)는, 다음의 수학식 13과 같이, 회전자의 위치를 추정할 수 있다. Meanwhile, the flux linkage flux estimated by the magnetic flux observer 310 in the position estimator 220 (

,

), The position calculating unit 320 in the position estimating unit 220 can estimate the position of the rotor, as shown in Equation 13 below.

)를 산출할 수 있게 된다.Here, A and B represent values calculated using the estimated linkage flux and the α-axis and β-axis currents iα and iβ, and by using this, simply estimated rotor position (

) Can be calculated.

)를 산출할 수 있게 된다.As a result, when the equations (12) and (13) are combined, the estimated rotor position can be simply estimated based on the phase resistance (Rs) and the q-axis inductance (Lq).

) Can be calculated.

On the other hand, with respect to the proportional constant K of the equation (11), according to the characteristics of the synchronous motor can be summarized as the following equation (14).

Since the magnet is not disposed inside the synchronous reluctance motor Synrm, the component of the linkage magnetic flux? Pm caused by the magnet is removed from the above-mentioned proportionality constant K in Equation (11).

In SPMSM, since the permanent magnet arrangement is a symmetrical structure and has no pole polarity, the d-axis inductance and the q-axis inductance are the same (Ld = Lq). Thus, only the linkage magnetic flux lambda pm component due to the magnet remains in the above-mentioned proportionality constant K of the equation (11).

Since the permanent magnet arrangement of the IPMSM is an asymmetrical structure, the proportionality constant K can be set using the above equation (11).

Meanwhile, the proportional constant K value may be a preset value.

As described above, according to an embodiment of the present invention, position estimation in the synchronous motor SM can be easily performed using the flux observer 310 in the stationary coordinate system. In particular, this position estimation method can be obtained simply and easily because only two motor parameters (phase resistance Rs and q-axis inductance Lq) are required. Further, regardless of the type of synchronous motor, it can be used easily.

5 is a flowchart illustrating a method of estimating a position of a synchronous motor according to an exemplary embodiment of the present invention.

Referring to the drawings, first, the three-phase output current flowing to the synchronous motor is detected (S510). As illustrated in FIG. 1, the three-phase output currents ia, ib and ic flowing between the synchronous motor 150 and the inverter 120 are detected using the output current detector E. FIG. Using three-phase equilibrium, it is also possible to detect only two phases. The detected output current is signal processed and input to the axis converter 210 in the controller 130.

Next, the three-phase output current is converted into a two-phase current of the stationary coordinate system (S520).

The axis conversion unit 210 converts the three-phase output currents (ia, ib, ic) into two-phase currents (iα, iβ) of the stationary coordinate system. To this end, as described above, Equation 1 may be used.

On the other hand, although not shown in the figure, the axis conversion unit 210 calculates the three-phase output voltage (va, vb, vc) based on the dc terminal voltage detected by the dc terminal voltage detection unit (B), and stops based on this. The two phase voltages vα and vβ of the coordinate system can also be converted.

,

)은 위치 연산부(320)에 입력될 수 있다. Next, the linkage flux is estimated based on the two-phase current and the phase resistance of the stationary coordinate system (S530). The position estimating unit 220, in particular the magnetic flux observation unit 310, based on the above equation (12), the two-phase current (iα, iβ), phase resistance (Rs) of the stationary coordinate system, and the two-phase voltage of the stationary coordinate system Using (vα, vβ), the linkage flux can be estimated. Estimated linkage flux (

,

) May be input to the position calculator 320.

,

), 정지 좌표계의 2상 전류(iα,iβ), 및 q축 인덕턴스(Lq)를 이용하여, 회전자 위치를 추정할 수 있다. Next, the rotor position is estimated based on the estimated linkage flux and q-axis inductance (S540). The position estimating unit 220, in particular, the position calculating unit 320, based on Equation 13, estimates the linkage flux (

,

), The rotor position can be estimated using the two-phase currents iα, iβ and the q-axis inductance Lq of the stationary coordinate system.

)는, 제520 단계(S520)에서, 삼상 출력 전류를 정지 좌표계의 2상 전류로 변환하는 경우에 사용될 수 있다.As such, the estimated rotor position (

) May be used when the three-phase output current is converted into the two-phase current of the stationary coordinate system in step 520.

In this way, the position estimation in the synchronous motor can be easily performed using the magnetic flux observation unit 310 in the stationary coordinate system without the position sensor. In particular, this position estimation method can be obtained simply and easily because only two motor parameters, specifically, phase resistance Rs and q-axis inductance Lq, are required.

2 and 3, the magnetic flux observer 310 and the position calculator 320 are provided in the position estimator 220. Alternatively, the magnetic flux observer 310 and the position calculator 320 may be provided separately.

On the other hand, the synchronous motor according to an embodiment of the present invention, a variety of examples are possible, the application range, such as laundry treatment equipment, vacuum cleaners, air conditioners and refrigerators such as home appliances, electric vehicles, hybrid cars, elevators, such as various power sources Can be applied to the need.

The method of estimating the position of the synchronous motor and the motor driving apparatus using the same according to the embodiment of the present invention are not limited to the configuration and method of the embodiments described as described above, the embodiments are various modifications All or part of each of the embodiments may be configured to be selectively combined to make it possible.

On the other hand, the position estimation method of the synchronous motor of the present invention can be implemented as a processor-readable code on a processor-readable recording medium provided in the motor driving apparatus. The processor-readable recording medium includes all kinds of recording devices that store data that can be read by the processor.

In addition, although the preferred embodiment of the present invention has been shown and described above, the present invention is not limited to the specific embodiments described above, but the technical field to which the invention belongs without departing from the spirit of the invention claimed in the claims. Of course, various modifications can be made by those skilled in the art, and these modifications should not be individually understood from the technical spirit or the prospect of the present invention.

Claims (10)

An output current detector for detecting a three-phase output current flowing to the synchronous motor;
An axis converting unit converting the three-phase output current into a two-phase current of a stationary coordinate system; And
And a position estimator for estimating the rotor position of the synchronous motor based on the two-phase current of the stationary coordinate system. The method of claim 1,
The position estimating unit,
A magnetic flux observation unit for estimating the linkage magnetic flux of the static coordinate system based on the two-phase current of the static coordinate system; And
And a position calculator configured to perform the rotor position estimation based on the estimated linkage magnetic flux. The method of claim 2,
The magnetic flux observation unit,
And the chain bridge magnetic flux is further estimated based on the two-phase voltage and the phase resistance of the stationary coordinate system. The method of claim 2,
The position calculation unit,
And based on the two-phase current and the q-axis inductance component of the stationary coordinate system, performing the rotor position estimation. The method of claim 1,
The axis conversion unit,
And receiving the estimated rotor position estimated by the position estimating unit, and converting the three-phase output current into a two-phase current of a stationary coordinate system. The method of claim 1,
An inverter that converts a predetermined DC power source into an AC power source having a predetermined frequency and outputs the AC power source to the synchronous motor;
A switching control signal output unit outputting a switching control signal to the inverter; And
And a second axis converting unit converting an input rotational coordinate system two-phase voltage command value into a three-phase voltage command value for generating the switching control signal. The method of claim 6,
The second axis conversion unit,
And receiving the estimated rotor position estimated by the position estimating unit, and converting the rotation coordinate system two-phase voltage command value into a three-phase voltage command value. Detecting a three-phase output current flowing to the synchronous motor;
Converting the three-phase output current into a two-phase current of the stationary coordinate system; And
Estimating a rotor position of the synchronous motor based on the two-phase current of the stationary coordinate system. The method of claim 8,
The rotor position estimation step,
Estimating the linkage flux of the stationary coordinate system based on the two-phase current of the stationary coordinate system; And
And calculating the rotor position based on the estimated linkage magnetic flux. The method of claim 8,
The conversion step,
And performing the conversion step by using the estimated rotor position.

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