JP2024122139A - Control device - Google Patents

Abstract

To provide a control device that can estimate phases of currents of a d-q coordinate system, in position sensor-less control.SOLUTION: A control device comprises: a coordinate converting part 51 that converts currents flowing into a motor to a γ-axis current value Iγ and a δ-axis current value Iδ; a γ-δ voltage command value calculating part 53 that calculates a γ-axis voltage command value V*γ on the basis of the γ-axis current value Iγ and a γ-axis current command value I*γ and calculates a δ-axis voltage command value V*δ on the basis of the δ-axis current value Iδ and a δ-axis current command value I*δ; a driving signal output part that converts the γ-axis voltage command value V*γ and the δ-axis voltage command value V*δ to driving signals; and a current phase estimating part 56 that calculates an estimated dq current phase θ^i, by introducing the γ-axis current value Iγ, the δ-axis current value Iδ, the γ-axis voltage command value V*γ and the δ-axis voltage command value V*δ into a derivation expression of instantaneous effective electric power and a derivation expression of instantaneous ineffective electric power that are represented using an extended inductive voltage model on a γ-δ coordinate system.SELECTED DRAWING: Figure 2

Description

This disclosure relates to a control device.

Position sensorless control, which controls a motor without using a position sensor, is known (see, for example, Patent Document 1).

JP 2006-20454 A

It is possible to control a motor using the current phase in the d-q coordinate system. However, in position sensorless control, the d-axis current value and the q-axis current value cannot be obtained, so the current phase in the d-q coordinate system cannot be directly calculated. In position sensorless control, there is no known method for estimating the current phase in the d-q coordinate system.

This disclosure describes a control device that can estimate the current phase in the d-q coordinate system in position sensorless control.

A control device according to one aspect of the present disclosure is a device that generates a drive signal to control an inverter that drives a motor. This control device includes a current value conversion unit that converts a current flowing through the motor into a γ-axis current value and a δ-axis current value, a γ-δ current command value output unit that outputs a γ-axis current command value and a δ-axis current command value, a γ-δ voltage command value calculation unit that calculates a γ-axis voltage command value based on the γ-axis current value and the γ-axis current command value and calculates a δ-axis voltage command value based on the δ-axis current value and the δ-axis current command value, a drive signal output unit that converts the γ-axis voltage command value and the δ-axis voltage command value into a drive signal, and an estimation unit that calculates an estimated dq current phase, which is an estimated value of the current phase in the d-q coordinate system, by introducing the γ-axis current value, the δ-axis current value, the γ-axis voltage command value, and the δ-axis voltage command value into a derivation formula for instantaneous active power and a derivation formula for instantaneous reactive power expressed using an extended induced voltage model on the γ-δ coordinate system.

In the above control device, the estimated dq current phase is calculated by introducing the γ-axis current value, δ-axis current value, γ-axis voltage command value, and δ-axis voltage command value into the derivation formula for instantaneous active power and the derivation formula for instantaneous reactive power expressed using the extended induced voltage model on the γ-δ coordinate system. When the instantaneous active power is expressed using the γ-axis current value, δ-axis current value, γ-axis voltage command value, and δ-axis voltage command value and then rearranged using the extended induced voltage model, the derivation formula for instantaneous active power includes a term for the product of the extended induced voltage and the q-axis current value. Similarly, when the instantaneous reactive power is expressed using the γ-axis current value, δ-axis current value, γ-axis voltage command value, and δ-axis voltage command value and then rearranged using the extended induced voltage model, the derivation formula for instantaneous reactive power includes a term for the product of the extended induced voltage and the d-axis current value. For example, the equation for deriving instantaneous active power can be solved for the product of the extended induced voltage and the q-axis current value, and the equation for deriving instantaneous reactive power can be solved for the product of the extended induced voltage and the d-axis current value, and an arctangent calculation can be performed to obtain the estimated dq current phase. As described above, it is possible to calculate the estimated dq current phase in position sensorless control. In other words, it is possible to estimate the current phase in the d-q coordinate system in position sensorless control.

The control device may further include a calculation unit that calculates a γδ current phase, which is the current phase in the γ-δ coordinate system, based on the γ-axis current value and the δ-axis current value, and a detection unit that detects motor out-of-step based on the estimated dq current phase and the γδ current phase. If the error between the dq current phase and the γδ current phase is large, the motor will out-of-step. With the above configuration, it is possible to detect motor out-of-step.

According to this disclosure, it is possible to estimate the current phase in the d-q coordinate system in position sensorless control.

FIG. 1 is a schematic configuration diagram of a control system including a control device according to an embodiment. FIG. 2 is a block diagram showing the functional configuration of the arithmetic unit shown in FIG. FIG. 3 is a diagram for explaining the relationship between the d-axis and the γ-axis. FIG. 4 is a diagram for explaining the accuracy of the estimated dq current phase θ^ _i .

The control device according to one embodiment will be described in detail below with reference to the accompanying drawings. In the description of the drawings, the same or equivalent elements are designated by the same reference numerals, and duplicate descriptions will be omitted.

With reference to FIG. 1, a schematic configuration of a control system including a control device according to one embodiment will be described. FIG. 1 is a schematic configuration diagram of a control system including a control device according to one embodiment. The control system 1 shown in FIG. 1 is a system that performs position sensorless control of a motor (electric motor) M. The motor M is a position sensorless motor, for example, a permanent magnet synchronous motor (PMSM). The motor M is mounted on a vehicle such as an electric forklift or a plug-in hybrid vehicle. The control system 1 includes an inverter circuit 2, a control device 3, and current sensors Se1, Se2, and Se3.

The inverter circuit 2 drives the motor M with DC power supplied from the DC power source PS. The inverter circuit 2 includes a capacitor C and switching elements SW1, SW2, SW3, SW4, SW5, and SW6.

Capacitor C smoothes the voltage output from DC power supply PS and input to inverter circuit 2.

The switching elements SW1 to SW6 are, for example, IGBTs (Insulated Gate Bipolar Transistors). The switching element SW1 is the switching element of the upper arm of the U phase. The switching element SW2 is the switching element of the lower arm of the U phase. The switching element SW3 is the switching element of the upper arm of the V phase. The switching element SW4 is the switching element of the lower arm of the V phase. The switching element SW5 is the switching element of the upper arm of the W phase. The switching element SW6 is the switching element of the lower arm of the W phase. One terminal of the capacitor C is connected to the positive terminal of the DC power supply PS and the collector terminals of the switching elements SW1, SW3, and SW5. The other terminal of the capacitor C is connected to the negative terminal of the DC power supply PS and the emitter terminals of the switching elements SW2, SW4, and SW6.

The connection point between the emitter terminal of switching element SW1 and the collector terminal of switching element SW2 is connected to the U-phase input terminal of motor M via current sensor Se1. The connection point between the emitter terminal of switching element SW3 and the collector terminal of switching element SW4 is connected to the V-phase input terminal of motor M via current sensor Se2. The connection point between the emitter terminal of switching element SW5 and the collector terminal of switching element SW6 is connected to the W-phase input terminal of motor M via current sensor Se3.

A drive signal is supplied from the control device 3 to the gates of each of the switching elements SW1 to SW6. Each of the switching elements SW1 to SW6 turns on or off based on the drive signal supplied to the gate. By turning on or off each of the switching elements SW1 to SW6, the DC power output from the DC power source PS is converted into three AC powers whose phases differ from each other by 120 degrees, and these AC powers are input to the input terminals of the three phases (U phase, V phase, and W phase) of the motor M, causing the rotor of the motor M to rotate.

The current sensors Se1 to Se3 are configured with Hall elements, shunt resistors, or the like. The current sensor Se1 detects a U-phase current value _Iu , which is the current value of the AC current flowing through the U-phase of the motor M, and outputs it to the control device 3. The current sensor Se2 detects a V-phase current value _Iv, which is the current value of the AC current flowing through the V-phase of the motor M, and outputs it to the control device 3. The current sensor Se3 detects a W-phase current value _Iw , which is the current value of the AC current flowing through the W-phase of the motor M, and outputs it to the control device 3. In this embodiment, the control system 1 includes three current sensors (current sensors Se1 to Se3), but may include two current sensors.

The control device 3 is a device that performs position sensorless control of the motor M. The control device 3 drives the motor M by controlling the inverter circuit 2. The control device 3 includes a drive circuit 4 and a calculator 5.

The drive circuit 4 is configured with an IC (Integrated Circuit) etc. The drive circuit 4 compares the U-phase voltage command value V ^* _u , the V-phase voltage command value V ^* _v , and the W-phase voltage command value V ^* _w output from the calculator 5 with a carrier wave (such as a triangular wave, a sawtooth wave, or an inverse sawtooth wave) and outputs drive signals according to the comparison results to the gate terminals of the switching elements SW1 to SW6.

The calculator 5 is an electronic control unit that is composed of a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory). For example, a program stored in the ROM is loaded onto the RAM and executed by the CPU, thereby realizing the various functions of the calculator 5 shown in FIG. 2.

Next, the functional configuration of the calculator 5 will be described with reference to Figs. 2 and 3. Fig. 2 is a block diagram showing the functional configuration of the calculator shown in Fig. 1. Fig. 3 is a diagram for explaining the relationship between the d-axis and the γ-axis. As shown in Fig. 2, the calculator 5 includes, as functional components, a coordinate conversion unit 51, a γ-δ current command value output unit 52, a γ-δ voltage command value calculation unit 53, a coordinate conversion unit 54, a position estimation unit 55, a current phase estimation unit 56 (estimation unit), a current phase calculation unit 57 (calculation unit), a calculation unit 58, and a detection unit 59.

The coordinate conversion unit 51 converts the U-phase current value _Iu , the V-phase current value _Iv , and the W-phase current value _Iw into a γ-axis current value _Iγ and a δ-axis current value _Iδ . The coordinate conversion unit 51 converts the U-phase current value _Iu , the V-phase current value _Iv , and the W-phase current value _Iw into _{a γ-axis current value Iγ and} a δ-axis current value _Iδ based on the estimated position θ^re output from the position estimation unit 55. That is, the coordinate conversion unit 51 functions as a current value conversion unit that converts the current flowing through the motor M into a γ-axis current value _Iγ and a δ-axis current value _Iδ . The estimated position θ^ _re is an estimated value of the position _θre of the rotor of the motor M. The position _θre is also referred to as an electrical angle. This conversion method is well known, so a detailed description thereof will be omitted here. The coordinate conversion unit 51 outputs the γ-axis current value _Iγ and the δ-axis current value _Iδ to the γ-δ voltage command value calculation unit 53, the position estimation unit 55, the current phase estimation unit 56, and the current phase calculation unit 57. The coordinate conversion unit 51 receives current values of two phases out of the U-phase current value _Iu , the V-phase current value _Iv , and the W-phase current value _Iw , and the current value of the remaining phase may be calculated from the input current values of the two phases.

In the notation "θ^ _re ", "^" is located to the upper right of "θ", but "θ^ _re " has the same meaning as the symbol written on the arrow from the position estimation unit 55 toward the coordinate conversion unit 51 in Fig. 2. The same applies to the other notations of "^". In this specification, the symbol "^" means an estimated value.

As shown in FIG. 3, the position θ _re is the angle between the α axis of the α-β coordinate system and the d axis of the d-q coordinate system. The estimated position θ^ _re is the angle between the α axis of the α-β coordinate system and the γ axis of the γ-δ coordinate system. The α-β coordinate system is a fixed coordinate system. The d-q coordinate system is a rotating coordinate system in which the direction of the north pole of the magnet of the motor M is the d axis and the direction perpendicular to the d axis is the q axis. The γ-δ coordinate system is an estimated rotating coordinate system in position sensorless control, in which the axis equivalent to the d axis of the d-q coordinate system is the γ axis and the axis equivalent to the q axis is the δ axis. The γ axis of the γ-δ coordinate system and the d axis of the d-q coordinate system are shifted by a position error Δθ _re .

The γ-δ current command value output unit 52 calculates a γ-axis current command value I ^* _γ and a δ-axis current command value I ^* _δ using the torque command value T ^* . The γ-δ current command value output unit 52 outputs the γ-axis current command value I ^* _γ and the δ-axis current command value I ^* _δ to the γ-δ voltage command value calculation unit 53.

The γ-δ voltage command value calculation unit 53 generates a γ-axis voltage command value V ^* _γ and a δ-axis voltage command value V ^* _δ . For example, the γ-δ voltage command value calculation unit 53 calculates a differential γ-axis current command value ΔI ^* _γ which is a difference between the γ-axis current command value I ^* _γ and the γ-axis current value _Iγ , and calculates a differential δ-axis current command value ΔI ^* _δ which is a difference between the δ-axis current command value I ^* _δ and _the δ-axis current value Iδ, and converts the differential γ-axis current command value ΔI ^* _γ and the differential δ-axis current command value ΔI ^* _δ into the γ-axis voltage command value V ^* _γ and the δ-axis voltage command value V ^* _δ . That is, the γ-δ voltage command value calculation unit 53 calculates the γ-axis voltage command value V ^* _γ based on the γ-axis current command value I ^* _γ and the γ-axis current value _Iγ , and calculates the δ-axis voltage command value V ^* _δ based on the δ-axis current command value I ^* _δ and the δ-axis current value _Iδ . The method of generating the γ-axis voltage command value V ^* _γ and the δ-axis voltage command value V ^* _δ is known, and therefore a detailed description thereof will be omitted here. The γ-δ voltage command value calculation unit 53 outputs the γ-axis voltage command value V ^* _γ and the δ-axis voltage command value V ^* _δ to the coordinate conversion unit 54 and the current phase estimation unit 56.

The coordinate conversion unit 54 is a functional unit that converts the γ-axis voltage command value V ^* _γ and the δ-axis voltage command value V ^* _δ into a U-phase voltage command value V ^* _u , a V-phase voltage command value V ^* _v , and a W-phase voltage command value V ^* _w . The coordinate conversion unit 54 converts the γ-axis voltage command value V ^* _γ and the δ-axis voltage command value V ^* _{δ into} a U-phase voltage command value V ^* _u , a V-phase voltage command value V ^* _v , and a W-phase voltage command value V ^* _w based on the estimated position θ^re output from the position estimation unit 55. This conversion method is well known, so a detailed description will be omitted here. The coordinate conversion unit 54 outputs the U-phase voltage command value V ^* _u , the V-phase voltage command value V ^* _v , and the W-phase voltage command value V ^* _w to the drive circuit 4. That is, the coordinate conversion section 54 and the drive circuit 4 function as a drive signal output section that converts the γ-axis voltage command value V ^* _γ and the δ-axis voltage command value V ^* _δ into drive signals.

The position estimator 55 calculates an estimated angular velocity ω^ _re and an estimated position θ^ _re . The position estimator 55 calculates an estimated extended electromotive force (EEMF) e generated in the motor M, an estimated extended electromotive force e^, based on the γ-axis current value _Iγ , the δ-axis current value _Iδ, and estimated motor parameters that can be estimated in advance, and calculates an estimated position θ^ _re , an estimated value of the position of the motor M, based on the estimated extended electromotive force e^. Specifically, for example, the position estimator 55 calculates a position error Δθ^ _re from the estimated extended electromotive force e^, and multiplies the position error Δθ^ _re by a predetermined transfer function to obtain an estimated angular velocity ω^ _re . The position estimator 55 then calculates the estimated position θ^ _re based on the estimated angular velocity ω^ _re and the position error Δθ^ _re . The position estimator 55 outputs the estimated position θ^ _re to the coordinate converters 51 and 54 , and outputs the estimated angular velocity ω^ _re to the current phase estimator 56 .

The current phase estimator 56 is a functional unit that calculates an estimated dq current phase θ^ _i . The estimated dq current phase θ^ _i is an estimated value of the dq current phase _θi , which is the current phase in the d-q coordinate system. Since the d-axis current value _Id and the q-axis current value _Iq are unknown, the current phase estimator 56 calculates the estimated dq current phase θ^ _i based on the γ-axis current value _Iγ , the δ-axis current value _Iδ , the γ-axis voltage command value V ^* _γ , and the δ-axis voltage command value V ^* _δ . To calculate the estimated dq current phase θ^ _i , an extended induced voltage model on the γ-δ coordinate system, a derivation formula for the instantaneous active power P, and a derivation formula for the instantaneous reactive power Q are used. Specifically, the estimated dq current phase θ^ _i is calculated by introducing the γ-axis current value I γ , the δ-axis current value I _δ , the γ-axis voltage command value V ^{*γ, and the δ-axis voltage command value V*} _δ ^into _the derivation equation for the instantaneous active power P and the derivation equation for the instantaneous reactive power Q, which are expressed using the extended induced voltage model on the γ- _δ coordinate system.

The extended induced voltage model (γ-axis voltage value V _γ and δ-axis voltage value V _δ ) on the γ-δ coordinate system is expressed by the formula (1) and the formula (2). Note that p represents the time differential operator d/dt. The winding resistance R^, the d-axis inductance L^ _d , and the q-axis inductance L^ _q are estimated values of the motor parameters of the motor M to be controlled, and are estimated in advance by measurements using the motor M. The motor parameters of the motor M are estimated values rather than actual values because the motor parameters vary depending on the current flowing through the motor M and the temperature. The position error Δθ _re is the true value of the angle between the γ-axis of the γ-δ coordinate system and the d-axis of the d-q coordinate system (or the angle between the δ-axis of the γ-δ coordinate system and the q-axis of the d-q coordinate system). When the position error Δθ _re is zero, the γ-axis coincides with the d-axis, and the δ-axis coincides with the q-axis. The first element of the second term on the right side of equation (1) represents the differential value of the position error Δθ _re . The extended induced voltage e is a component that occurs only on the q axis.

By transforming the equations for deriving the instantaneous active power P and the instantaneous reactive power Q using equations (1) and (2), equations (3) and (4) are obtained, respectively.

The current amplitude I is expressed by equation (5) using the γ-axis current value _Iγ and the δ-axis current value _Iδ .

Equation (3) includes a product term of the extended induced voltage e and the q-axis current value _Iq , and equation (4) includes a product term of the extended induced voltage e and the d-axis current value _Id . Therefore, the estimated dq current phase θ^ _i is calculated by equation (6).

Here, the derivative of the position error Δθ _re is an unknown value, but is small enough to be ignored. Therefore, by setting the derivative of the position error Δθ _re in equation (6) to zero, equation (7) can be obtained.

As shown in equation (8), if it is assumed that the differential term of the position error Δθ _re and the current differential term cancel each other out, equation (9) can be obtained from equation (6).

The current phase estimator 56 calculates the estimated dq current phase θ^ _i by using the formula (7) or (9). The γ-axis voltage command value V ^* _γ is used as the γ-axis voltage value _Vγ , and the δ-axis voltage command value V ^* _δ is used as the δ-axis voltage value _Vδ . The current phase estimator 56 outputs the estimated dq current phase θ^ _i to the calculator 58.

The current phase calculation unit 57 is a functional unit that calculates the γδ current phase θ _γδ . The γδ current phase θ _γδ is the current phase in the γ-δ coordinate system. The current phase calculation unit 57 calculates the γδ current phase θ _γδ based on the γ-axis current value I _γ and the δ-axis current value I _δ . Specifically, the current phase calculation unit 57 calculates the γδ current phase θ _γδ by equation (10). The current phase calculation unit 57 outputs the γδ current phase θ _γδ to the calculation unit 58.

The calculation unit 58 is a functional unit that calculates the estimated position error Δθ^ _re . The estimated position error Δθ^ _re is an estimated value of the position error Δθre. The calculation unit 58 calculates the estimated position error Δθ^ _re based on the estimated dq current phase θ^ _i and the γδ current phase _θγδ . Specifically, the calculation unit 58 calculates the estimated position error Δθ^ _re by subtracting the γδ current phase _θγδ from the estimated dq current phase θ^ _i as shown in equation (11). The calculation unit 58 outputs _{the estimated position error Δθ^re to} the detection unit 59.

The detection unit 59 is a functional unit that detects out-of-step of the motor M. The detection unit 59 detects out-of-step of the motor M based on the estimated position error Δθ^ _re . Therefore, it can be said that the detection unit 59 detects out-of-step of the motor M based on the estimated dq current phase θ^ _i and the γδ current phase _θγδ . Specifically, the detection unit 59 compares the estimated position error Δθ^ _re with a predetermined threshold value, and determines that out-of-step of the motor M has occurred when the estimated position error Δθ^ _re is greater than the threshold value, and determines that out-of-step of the motor M has not occurred when the estimated position error Δθ^ _re is equal to or smaller than the threshold value. For example, π/2 (rad) is used as the threshold value. Note that when it is determined that out-of-step of the motor M has occurred, the motor M may be stopped.

Next, the accuracy of the estimated dq current phase θ^ _i will be described with reference to Fig. 4. Fig. 4 is a diagram for explaining the accuracy of the estimated dq current phase θ^ _i . The horizontal axis of Fig. 4 indicates time (unit: seconds), and the vertical axis of Fig. 4 indicates the current phase (unit: radians). The dq current phase θ^ _i is a true value obtained by attaching a sensor to the motor M to be controlled. The estimated dq current phase θ^ _i is an estimated value calculated by equation (9).

4, in a period when the motor M is not losing synchronism, the estimated dq current phase θ^ _i substantially coincides with the dq current phase _θi . In a period when the motor M is losing synchronism, the estimated dq current phase θ^ _i is slightly different from the dq current phase _θi , but it can be said that they generally coincide with each other. Therefore, it can be said that the estimated dq current phase θ^ _i is calculated with high accuracy, regardless of whether the motor M is losing synchronism or not.

In the control device 3 described above, the estimated dq current phase θ^ _i is calculated by introducing the γ-axis current value I γ , the δ-axis current value I _δ , the γ-axis voltage command value V* _γ , and the δ-axis voltage command value V ^* _δ into the derivation formula for the instantaneous active power P and the derivation formula for the instantaneous reactive power Q, which are expressed using the extended induced voltage model on the γ ^- _δ coordinate system. When the instantaneous active power P is expressed by the γ-axis current value I _γ , the δ-axis current value I _δ , the γ-axis voltage command value V ^* _γ , and the δ-axis voltage command value V ^* _δ and then rearranged using the extended induced voltage model, the derivation formula for the instantaneous active power P includes a term for the product of the extended induced voltage e and the q-axis current value _Iq . Similarly, when the instantaneous reactive power Q is expressed by the γ-axis current value I _γ , the δ-axis current value I _δ , the γ-axis voltage command value V ^* _γ , and the δ-axis voltage command value V ^* _δ , and then rearranged using the extended induced voltage model, the derivation formula of the instantaneous reactive power Q includes a product term of the extended induced voltage e and the d-axis current value _Id . The derivation formula of the instantaneous active power P is solved for the product term of the extended induced voltage e and the q-axis current value _Iq , and the derivation formula of the instantaneous reactive power Q is solved for the product term of the extended induced voltage e and the d-axis current value _Id , and an arctangent calculation is performed to obtain the estimated dq current phase θ^ _i . As described above, in the position sensorless control, it is possible to calculate the estimated dq current phase θ^ _i . That is, in the position sensorless control, it is possible to estimate the current phase of the d-q coordinate system.

When the error between the dq current phase _θi and the γδ current phase _θγδ is large, the motor M will lose synchronization. In the control device 3, the current phase calculation unit 57 calculates the γδ current phase _θγδ based on the γ-axis current value _Iγ and the δ-axis current value _Iδ . The detection unit 59 detects loss of synchronization of the motor M based on the estimated position error Δθ^ _re calculated based on the estimated dq current phase θ^ _i and the γδ current phase _θγδ . Therefore, loss of synchronization of the motor M can be detected.

Although one embodiment of the present disclosure has been described in detail above, the control device according to the present disclosure is not limited to the above embodiment.

In the above embodiment, the estimated dq current phase θ^ _i is used to detect loss of synchronism of the motor M, but it may be used for purposes other than detecting loss of synchronism of the motor M. For example, the estimated dq current phase θ^ _i may be used for feedback to PWM (Pulse Width Modulation) control. In this case, in calculating the estimated dq current phase θ^ _i , the γ-axis current command value I ^* _γ may be used as the γ-axis current value _Iγ , and the δ-axis current command value I ^* _δ may be used as the δ-axis current value _Iδ . The calculator 5 does not need to include the current phase calculation unit 57, the calculation unit 58, and the detection unit 59.

3...Control device, 4...Drive circuit (drive signal output section), 51...Coordinate conversion section (current value conversion section), 52...γ-δ current command value output section, 53...γ-δ voltage command value calculation section, 54...Coordinate conversion section (drive signal output section), 55...Position estimation section, 56...Current phase estimation section (estimation section), 57...Current phase calculation section (calculation section), 58...Calculation section, 59...Detection section, M...Motor.

Claims (2)

A control device that generates a drive signal to control an inverter that drives a motor,
a current value converter for converting a current flowing through the motor into a γ-axis current value and a δ-axis current value;
a γ-δ current command value output unit that outputs a γ-axis current command value and a δ-axis current command value;
a γ-δ voltage command value calculation unit that calculates a γ-axis voltage command value based on the γ-axis current value and the γ-axis current command value, and calculates a δ-axis voltage command value based on the δ-axis current value and the δ-axis current command value;
a drive signal output unit that converts the γ-axis voltage command value and the δ-axis voltage command value into the drive signals;
an estimation unit that calculates an estimated dq current phase, which is an estimated value of a current phase in a d-q coordinate system, by introducing the γ-axis current value, the δ-axis current value, the γ-axis voltage command value, and the δ-axis voltage command value into a derivation equation for instantaneous active power and a derivation equation for instantaneous reactive power expressed using an extended induced voltage model on a γ-δ coordinate system;
A control device comprising: a calculation unit that calculates a γδ current phase, which is a current phase in a γ-δ coordinate system, based on the γ-axis current value and the δ-axis current value;
The control device according to claim 1 , further comprising: a detection unit that detects a loss of synchronization of the motor based on the estimated dq current phase and the γδ current phase.

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