JP7160641B2 - motor controller - Google Patents

Description

The present invention relates to a motor control device for controlling a PM (Permanent Magnet) motor, and more particularly to a technique for adjusting the magnetic pole phase of the PM motor to 0°.

Conventionally, a PM motor using a permanent magnet (ferromagnetic material) for a rotor (rotor) is known. is required.

In order to detect the magnetic pole phase of the PM motor, for example, an absolute encoder connected to the PM motor is used (see, for example, Patent Document 1).

A motor control device that controls a PM motor detects a magnetic pole phase from an absolute value encoder connected to the PM motor, for example, when the power is turned on, and converts the detected magnetic pole phase into a dq-axis signal of a rotating coordinate system and a three-phase alternating current. Used as an electrical angle for coordinate conversion between signals. Then, the motor control device then receives speed feedback from an encoder provided for detecting the speed of the PM motor, calculates an electrical angle from the speed feedback, and performs the above-described coordinate conversion to thereby control the PM motor. Control.

Thus, the motor control device can detect the magnetic pole phase of the PM motor and control the PM motor by using the absolute value encoder.

JP-A-2002-223582

However, the absolute encoder described above is only used at power up to detect the pole phase and is not used thereafter for PM motor control.

Therefore, from the viewpoint of reducing the cost of equipment for controlling the PM motor, it has been desired to eliminate the absolute value encoder and provide a simple means to replace the absolute value encoder. For example, if the magnetic pole phase of the PM motor can be forcibly adjusted to 0° when the power is turned on, there is no need to detect the magnetic pole phase and the need to use an absolute encoder.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made to solve the above-mentioned problems, and its object is to provide a motor control apparatus that eliminates the need for an absolute encoder by providing means for adjusting the magnetic pole phase of a PM motor to 0°. is to provide

In order to solve the above problems, a motor control device according to claim 1 generates an excitation voltage command from an excitation current command, generates a torque voltage command from a torque current command, and generates an electrical angle from a speed feedback of a PM motor. a motor control for converting the excitation voltage command and the torque voltage command into a three-phase AC voltage command based on the electrical angle, and controlling the PM motor via a power amplifier based on the three-phase AC voltage command; In the apparatus, a preset DC excitation current command is subjected to filtering based on a predetermined speed command to generate the excitation current command, and the excitation current deviation between the excitation current command and the excitation current feedback is zero. and a DC excitation control unit for generating the excitation voltage command, and a speed control using a predetermined gain so that the speed deviation between the speed command and the speed feedback becomes zero a torque control unit for generating the torque current command, performing current control so that a torque current deviation between the torque current command and the torque current feedback becomes zero, and generating the torque voltage command; An electrical angular velocity is generated based on the velocity feedback, a filtering process is performed on the electrical angular velocity based on the velocity command, an electrical angular velocity command is generated, and one of the electrical angular velocity and the electrical angular velocity command is selected. an electrical angle control unit for performing integration processing to generate the electrical angle; and the excitation voltage command generated by the DC excitation control unit and the a first coordinate transformation unit for transforming the torque voltage command generated by the torque control unit into the three-phase AC voltage command; a second coordinate transformation unit for transforming three-phase AC current feedback detected by a current detector provided between the PM motor and the excitation current feedback and the torque current feedback; mode, the DC excitation control unit generates the excitation current command reflecting the DC excitation current command through the filtering process based on the zero-value speed command in the initial mode, and the current In control, the excitation voltage command reflecting the DC excitation current command is generated, the torque control unit sets a preset gain lower limit value to the gain, and the zero value in the initial mode is set to the gain. using the gain lower limit value based on the speed command The speed control generates the 0-value torque current command; the current control generates the 0-value torque voltage command; The filter processing based on the speed command generates the electrical angular velocity command of 0 value, selects the electrical angular velocity command, performs the integration process, and generates the electrical angle of 0°. do.

Further, the motor control device according to claim 2 is the motor control device according to claim 1, wherein the DC excitation control unit sets the DC excitation current command to i0, the speed command to ω ^* , and the predetermined parameter to _P0 . , where the excitation current command is i _d ^* , the filter for performing the filtering process and the excitation current generated by the filter are expressed by the formula: i _d ^* = (1/(1+P ₀ ω ^*2 ))·i0 a subtractor for obtaining the excitation current deviation by subtracting the excitation current feedback from the command; and a current for generating the excitation voltage command by performing the current control so that the excitation current deviation obtained by the subtractor becomes zero. and a controller.

Further, the motor control device of claim 3 is the motor control device of claim 1 or 2, wherein the torque control unit subtracts the speed feedback from the speed command to obtain the speed deviation. , the preset gain is K _V ^* , the speed feedback is ω, the predetermined parameter is P ₀ , and the gain after filtering is K _V ^* ', the formula: K _V ^* '=(P ₀ ω ² / (1+P ₀ ω ² ))·K _V ^* is a filter that performs filtering, and if the gain after filtering generated by the filter is equal to or less than a preset threshold value, the gain lower limit value is output. a limiter for outputting the gain set in advance when the gain after filtering is greater than the threshold; a speed controller that performs the speed control using the gain lower limit value or the gain that is set to generate the torque current command; and a speed controller that subtracts the torque current feedback from the torque current command generated by the speed controller. a second subtractor for obtaining the torque current deviation; and a current controller for performing the current control so that the torque current deviation obtained by the second subtractor becomes 0 and generating the torque voltage command. It is characterized by having

The motor control device of claim 4 is the motor control device of any one of claims 1 to 3, wherein the electrical angle control unit multiplies the speed feedback by a preset number of opposite poles. , a multiplier for generating the electrical angular _velocity , ^a formula ^: ω _e ^* _{= (} P ₀ ω ^*2 /(1+P ₀ ω ^*2 ))·ω _e selects the filter for performing the filtering process and the electrical angular velocity command generated by the filter in the initial mode, and selects the initial mode is switched to an operation mode, and in the operation mode, a switch for selecting the electrical angular velocity generated by the multiplier; and an integrator for generating an angle.

As described above, according to the present invention, the magnetic pole phase of the PM motor can be adjusted to 0°, so there is no need to use an absolute encoder to detect the magnetic pole phase. Therefore, the absolute value encoder can be eliminated from the facility for controlling the PM motor, and the cost can be reduced.

1 is an overall diagram showing a configuration example of a motor control system including a motor control device according to an embodiment of the present invention; FIG. It is a block diagram which shows the structural example of a DC-excitation control part. 4 is a block diagram showing a configuration example of a torque control unit; FIG. 4 is a block diagram showing a configuration example of an electrical angle control unit; FIG. 4 is a time chart for explaining the operation of setting the magnetic pole phase δ to 0° by DC excitation; It is a figure explaining a simulation result.

EMBODIMENT OF THE INVENTION Hereinafter, the form for implementing this invention is demonstrated in detail using drawing. The present invention is characterized in that in the initial mode when the power is turned on, DC excitation is performed while the PM motor is not rotating, and the magnetic pole phase δ is adjusted (set) to 0°.

[Motor control system]
First, the motor control system will be explained. FIG. 1 is an overall diagram showing a configuration example of a motor control system including a motor control device according to an embodiment of the present invention. This motor control system includes a motor control device 1 , a power amplifier 2 , a motor 3 and a PG (pulse generator) 4 .

The motor control device 1 is a device that performs vector control of the motor 3 on the d-axis and the q-axis. In the initial mode when the power is turned on, the motor control device 1 sets the electrical angle θ _e to 0° while the motor 3 is not rotating, and DC-excites the motor 3 to set the magnetic pole phase δ to 0°. set.

After that, when the motor control device 1 switches from the initial mode to the operation mode, it calculates the electrical angle θ _e based on the speed feedback ω (rotational speed of the motor 3) input from PG4. Based on the electrical angle θ _e , the motor control device 1 performs coordinate conversion between the dq-axis signal of the rotating coordinate system and the three-phase AC signal.

The motor control device 1 outputs a _U -phase AC voltage command Vu ^* , a _V -phase AC voltage command Vv ^* , and a _W -phase AC voltage command Vw ^* , which are three-phase AC voltage commands after coordinate conversion, to the power amplifier 2. .

The motor control device 1 provides U-phase AC current feedback i _u , V-phase AC current feedback i _v and W Input phase alternating current feedback i _w . Then, the motor control device 1 generates excitation current feedback _id and torque current feedback _iq by coordinate transformation. The motor controller 1 controls the motor 3 in this way. Details of the motor control device 1 will be described later.

The power amplifier 2 has an inverter. A power amplifier 2 receives a _U -phase AC voltage command Vu ^* , a _V -phase AC voltage command Vv ^* , and a _W -phase AC voltage command Vw ^* from the motor control device 1, and generates a PWM signal from these three-phase AC voltage commands. to generate The power amplifier 2 turns on and off the gates of the switching elements of the inverter according to the PWM signal to switch the DC bus voltage input to the inverter and convert it into an AC voltage. A power amplifier 2 supplies an AC voltage to the motor 3 .

The motor 3 is a PM motor, and for example, a PMSM (Permanent Magnet Synchronous Motor) is used.

The PG 4 generates a pulse signal corresponding to the rotation of the motor 3, and outputs the rotation speed of the motor 3 obtained from the count value of the pulse signal to the motor control device 1 as a speed feedback ω. It should be noted that FIG. 1 omits the illustration so that the speed feedback ω is input from PG 4 to the motor control device 1 .

[Motor control device 1]
Next, the motor control device 1 shown in FIG. 1 will be described in detail. The motor control device 1 includes a DC excitation control section 10, a torque control section 11, an electrical angle control section 12, and coordinate conversion sections 13 and 14. As shown in FIG. FIG. 1 shows only components directly related to the present invention, and components not directly related are omitted.

The DC excitation control unit 10 receives a preset DC excitation current command _i0 , a predetermined speed command ω ^* , and an excitation current feedback id from the coordinate conversion unit 14 . In the initial mode when power is turned on, the DC excitation control unit 10 performs DC excitation and outputs an excitation voltage command V _d ^* generated by current control to the coordinate conversion unit 13 . On the other hand, the DC excitation control unit 10 outputs an excitation voltage command V _d ^* =0 (0 value, 0% value) generated by current control to the coordinate conversion unit 13 in the operation mode.

Specifically, in the initial mode when the power is turned on, the DC excitation control unit 10 generates the exciting current command i _d ^* =i0 using the fact that the speed command ω ^* =0. Then, the DC excitation control unit 10 generates the excitation voltage command V _d ^* by current control so that the excitation current deviation between the excitation current command i _d ^* =i0 and the excitation current feedback i _d becomes 0. , and outputs the excitation voltage command V _d ^* to the coordinate conversion unit 13 .

As a result, DC excitation is performed in a state of torque voltage command V _q ^* =0 output by the torque control unit 11 (described later) and electrical angle θ _e =0 output by the electrical angle control unit 12 (details will be described later). , and the magnetic pole phase .delta. of the motor 3 is set to 0.degree.

When the initial mode is switched to the operation mode, the DC excitation control unit 10 starts operation according to a predetermined speed pattern and stops DC excitation. In the operation mode, the DC excitation control unit 10 generates an excitation current command i _d ^* =0 by utilizing the fact that the speed command ω ^* >0, and performs current control based on the excitation current command i _d ^* =0. to generate an excitation voltage command V _d ^* =0, and output the excitation voltage command V _d ^* =0 to the coordinate conversion unit 13 .

The torque control unit 11 receives a predetermined speed command ω ^* , a speed feedback ω, and a torque current feedback i _q from the coordinate conversion unit 14 . The torque control unit 11 also receives an initial mode signal INIT@ indicating whether or not it is the initial mode when the power is turned on. In the initial mode when the power is turned on, the torque control unit 11 generates a small-change torque current command i _q ^* = 0 by speed control, and generates a small-change torque voltage command V _q ^* = 0 by current control. is output to the coordinate transformation unit 13 . Also, in the operation mode, the torque control unit 11 generates a torque current command i _q ^* by speed control, and outputs a torque voltage command V _q ^* generated by current control to the coordinate conversion unit 13 .

Specifically, in the initial mode when the power is turned on, the torque control unit 11 utilizes the speed feedback ω=0 to set the gain of the speed controller 33 (to be described later) to the minimum value, and the speed controller The torque command T ^* calculated by 33 is suppressed. Further, the torque control unit 11 inputs an initial mode signal INIT@=1 (ON) indicating the initial mode when the power is turned on, and thus the estimated load value TL^ of the load feedforward compensator 35, which will be described later, is input. is set to 0 so that the estimated load value TL' is not reflected in the torque command T ^* .

The torque control unit 11 utilizes the fact that the speed command ω ^* =0 and the speed feedback ω=0 to generate a torque current command i _q ^* =0 that changes little in speed control, and the torque current command i _q ^* =0 to generate a torque voltage command _Vq ^* =0 with little change in the current control.

As a result, in the initial mode when the power is turned on, the torque voltage command V _q ^* =0 output by the torque control unit 11 is suppressed from changing. In this case, even if the speed feedback ω=0 changes to the speed feedback ω≠0, the torque current command i _q ^* =0 with little change is generated and the torque voltage command V _q ^* =0 is generated. Then, DC excitation is performed in a state where the torque voltage command V _q ^* =0, and the magnetic pole phase δ of the motor 3 is set to 0°.

When the initial mode is switched to the operation mode, the torque control unit 11 starts operation according to a predetermined speed pattern, the speed feedback ω>0, and sets the gain of the speed controller 33, which will be described later, to a normal value. Further, when the initial mode signal INIT@=0 (off) is input to the torque control unit 11, the load feedforward compensator 35, which will be described later, outputs an estimated load value TL` to output an estimated load value TL`. is reflected in the torque command T ^* . The torque control unit 11 generates a torque voltage command V _{q * by current control based on the torque current command i q *, and outputs the torque voltage command V q} ^* _to ^the _coordinate ^conversion unit 13 .

The electrical angle control unit 12 receives a speed feedback ω, a predetermined speed command ω ^* , and an initial mode signal INIT@. The electrical angle control unit 12 outputs the electrical angle θ _e =0 to the coordinate transformation units 13 and 14 in the initial mode when the power is turned on, and outputs the electrical angle θ _e calculated from the speed feedback ω to the coordinate transformation units 13 and 14 in the operation mode. Output to 13 and 14.

Specifically, in the initial mode when the power is turned on, the electrical angle control unit 12 receives an initial mode signal INIT@=1, resets the integrator 43, which will be described later, and sets the speed command ω ^* =0. to generate the electrical angle θ _e =0. The electrical angle control unit 12 outputs the electrical angle θ _e =0 to the coordinate conversion units 13 and 14 .

As a result, coordinate conversion based on the electrical angle θ _e =0 is performed in the initial mode when the power is turned on. That is, DC excitation is performed in the state of the electrical angle θ _e =0, and the magnetic pole phase δ of the motor 3 is set to 0°.

When the initial mode is switched to the operation mode, the electrical angle control unit 12 receives an initial mode signal INIT@=0, starts operation according to a predetermined speed pattern, and becomes speed feedback ω>0. Then, the electrical angle control section 12 generates an electrical angle θ _e based on the speed feedback ω, and outputs the electrical angle θ _e to the coordinate conversion sections 13 and 14 .

The coordinate conversion unit 13 receives the excitation voltage command V _d ^* from the DC excitation control unit 10, the torque voltage command V _q ^* from the torque control unit 11, and the electrical angle θ _e from the electrical angle control unit 12. input.

The coordinate conversion unit 13 converts the excitation voltage command V _d ^* and the torque voltage command V _q ^* of the rotating coordinate system into the U-phase AC voltage command V _u ^* and the V-phase AC voltage command V _v ^* based on the electrical angle θ _e . and W-phase AC voltage command V _w ^* . The coordinate conversion unit 13 outputs the U-phase AC voltage command V _u ^* , the V-phase AC voltage command V _v ^* , and the W-phase AC voltage command V _w ^* to the power amplifier 2 .

Coordinate transformation unit 14 converts U-phase alternating current feedback i _u , V-phase alternating current feedback i _v , and W-phase alternating current feedback i _w detected by a current detector provided between power amplifier 2 and motor 3 to input. The coordinate conversion unit 14 also receives the electrical angle θ _e from the electrical angle control unit 12 .

The coordinate transformation unit 14 transforms the U-phase alternating current feedback i _u , the V-phase alternating current feedback i _v and the W-phase alternating current feedback i _w into the excitation current feedback i _d and the torque of the rotating coordinate system based on the electrical angle θ _e . Coordinate transformation to current feedback i _q . The coordinate transformation unit 14 outputs the excitation current feedback i _d to the DC excitation control unit 10 and outputs the torque current feedback i _q to the torque control unit 11 .

[DC excitation control unit 10]
Next, the DC excitation control section 10 shown in FIG. 1 will be described in detail. FIG. 2 is a block diagram showing a configuration example of the DC excitation control section 10. As shown in FIG. This DC excitation control section 10 comprises a filter 20 , a subtractor 21 and a current controller 22 .

The filter 20 receives a DC excitation current command i0 and a predetermined speed command ω ^* , filters the DC excitation current command i0 according to the following equation, and calculates an excitation current command i _d ^* . and outputs the excitation current command i _d ^* to the subtractor 21 .
[Number 1]
i _d ^* = (1/(1+P ₀ ω ^*2 )) i0 (1)
P ₀ is a preset threshold.

Here, the filter 20 inputs the DC excitation current command i0 when the user performs an operation to turn on the operation in the initial mode when the power is turned on. Since the speed command ω ^* =0 in the initial mode when the power is turned on, the filter 20 calculates the exciting current command id ^* = _i0 and outputs it to the subtractor 21 .

Then, when the initial mode is switched to the operation mode, operation is started according to a predetermined speed pattern, and the speed command ω ^* >0. Since the denominator of equation (1)>>1 in the operating mode, the filter 20 calculates the exciting current command i _d ^* =0 and outputs it to the subtractor 21 .

The subtractor 21 receives the excitation current command _id ^* from the filter 20, receives the excitation current feedback _id from the coordinate conversion unit 14, subtracts the excitation current feedback _id from the excitation current command id*, and obtains the excitation current command _id ^* . Find the current deviation. The subtractor 21 then outputs the excitation current deviation to the current controller 22 .

The current controller 22 receives the excitation current deviation from the subtractor 21, performs current control by PI control using preset proportional gain and integral gain so that the excitation current deviation becomes 0, and outputs the excitation voltage command Calculate V _d ^* . The current controller 22 then outputs the excitation voltage command V _d ^* to the coordinate conversion section 13 .

Here, the current controller 22 outputs the excitation voltage command V _d ^* calculated by current control based on the excitation current command _id ^* =i0 to the coordinate conversion section 13 in the initial mode when the power is turned on. DC excitation is thereby performed.

Then, when the initial mode is switched to the operation mode, the current controller 22 converts the excitation voltage command V _d ^* =0 calculated by the current control based on the excitation current command i _d ^* =0 in the operation mode to the coordinate conversion unit 13 . output to

As described above, according to the DC excitation control unit 10, in the initial mode when the power is turned on, the filter 20 generates the excitation current command id ^* = _i0 by utilizing the fact that the speed command ω ^* =0. . Then, the current controller 22 outputs the excitation voltage command V _d ^* generated by the current control to the coordinate conversion section 13 . DC excitation is thereby performed.

Further, in the operation mode, the filter 20 utilizes the fact that the speed command ω ^* >0 to generate an excitation current command i _d ^* =0, and an excitation voltage command V _d ^* =0 generated by current control. is output to the coordinate transformation unit 13 . As a result, normal motor control is performed.

[Torque control unit 11]
Next, the torque control section 11 shown in FIG. 1 will be described in detail. FIG. 3 is a block diagram showing a configuration example of the torque control section 11. As shown in FIG. The torque controller 11 includes subtractors 30 and 38, a filter 31, a limiter 32, a speed controller 33, multipliers 34 and 37, a load feedforward compensator 35, an adder 36 and a current controller 39.

A subtractor 30 receives a predetermined speed command ω ^* and a speed feedback ω, subtracts the speed feedback ω from the speed command ω ^* , and obtains a speed deviation. The subtractor 30 then outputs the speed deviation to the speed controller 33 .

The filter 31 receives the velocity feedback ω and a preset gain K _V ^* , performs filtering on the gain K _V ^* according to the following formula, and calculates the gain K _V ^* ', Gain K _V ^* ' is output to limiter 32 .
[Number 2]
K _V ^* '=(P ₀ ω ² /(1+P ₀ ω ² ))·K _V ^* (2)

The limiter 32 receives the gain _KV ^{*' from the filter 31, performs limiter processing on the gain KV*} _' ^, and uses the preset gain _KV ^* or the preset gain lower limit value _KVmin as the gain _KV . Output to speed controller 33 .

Specifically, the limiter 32 compares the gain K _V ^* ' with a preset threshold value, and if it determines that the gain K _V ^* ' is equal to or less than the threshold value, sets the preset gain lower limit value K _Vmin to It is output to the speed controller 33 as a gain _KV .

On the other hand, when the limiter 32 determines that the gain K _V ^* ' is greater than the threshold value, it outputs the preset gain K _V ^* to the speed controller 33 as the gain K _V . The gain K _V ^* is the same as the gain K _V ^* that filter 31 inputs.

The speed controller 33 receives the speed deviation from the subtractor 30 and the gain K _V from the limiter 32 . Then, the speed controller 33 performs current control by P control using the gain K _V so that the speed deviation becomes 0, and calculates the torque command T ^* . The speed controller 33 then outputs the torque command T ^* to the adder 36 and multiplier 34 .

Here, in the initial mode when the power is turned on, since the velocity feedback ω=0, the filter 31 outputs the gain K _V ^* '=0, and the limiter 32 outputs the gain K _V ^* '=0 below the threshold. and output gain K _V =K _Vmin . Then, the speed controller 33 inputs the speed deviation 0 calculated from the speed command ω ^* =0 and the speed feedback ω=0, and controls the speed using the gain lower limit value K _Vmin which is the lower limit value of the gain K _V. and output the torque command T ^* . As a result, in the initial mode when the power is turned on, even if the speed feedback ω=0 changes to the speed feedback ω≠0, the torque command T ^* becomes a command of 0 with little change.

Then, when the initial mode is switched to the operation mode, operation according to a predetermined speed pattern is started, and the speed command ω ^* >0 and the speed feedback ω>0. The filter 31 outputs the filtered gain K _V ^* ', the limiter 32 determines that the gain K _V ^* ' is greater than the threshold, and outputs the gain K _V =K _V ^* . Then, the speed controller 33 performs speed control using the gain K _V =K _V ^* and outputs a torque command T ^* . As a result, the torque command T ^* calculated using the normal gain K _V =K _V ^* is output in the operation mode.

Multiplier 34 receives torque command T ^* from speed controller 33 , multiplies torque command T ^* by torque constant estimated value K _T ^, and outputs the multiplication result to load feedforward compensator 35 . The torque constant estimated value K _T ^ is assumed to be a torque constant estimated by a calculation unit (not shown).

The load feedforward compensator 35 receives the multiplication result from the multiplier 34, the speed feedback ω, and the initial mode signal INIT@. Then, the load feedforward compensator 35 calculates an estimated load estimate TL' for compensating the load torque based on the initial mode signal INIT@, the multiplication result, and the speed feedback ω, and calculates the estimated load estimate TL' as Output to adder 36 .

The adder 36 receives the torque command T ^* from the speed controller 33, inputs the estimated load value TL` from the load feedforward compensator 35, and adds the estimated load value TL` to the torque command T ^* . , to obtain the torque command T ^* after load feedforward compensation. The adder 36 then outputs the torque command T ^* after load feedforward compensation to the multiplier 37 .

The multiplier 37 receives the torque command T ^* after load feedforward compensation from the adder 36, multiplies the torque command T ^* after load feedforward compensation by the torque constant estimated value K _T ^, and obtains the torque current command i _q ^* , and outputs the torque current command i _q ^* to the subtractor 38 .

Here, in the initial mode when the power is turned on, when the load feedforward compensator 35 receives the initial mode signal INIT@=1, the load feedforward compensator 35 sets the estimated load estimate value TL`=0, and the estimated load estimate value TL`= Output 0. The adder 36 outputs the torque command T ^* input from the speed controller 33 as it is, and the multiplier 37 outputs the torque current command i _q ^* without load feedforward compensation.

Then, when the initial mode is switched to the operating mode, the load feedforward compensator 35 inputs the initial mode signal INIT@=0 in the operating mode, and estimates the speed of the motor 3 based on the multiplication result input from the multiplier 34. find the value. Then, the load feedforward compensator 35 obtains the deviation between the speed estimate and the speed feedback .omega., obtains the estimated load value TL` based on the deviation, and outputs the estimated load value TL`. The estimated load estimated value TL' is a value for compensating the load torque based on the deviation. A multiplier 37 outputs a torque current command i _q ^* with load feedforward compensation.

The subtractor 38 receives the torque current command i _q ^* from the multiplier 37, receives the torque current feedback i _q from the coordinate conversion unit 14, subtracts the torque current feedback i _q from the torque current command i _q ^* , Find the torque current deviation. The subtractor 38 then outputs the torque current deviation to the current controller 39 .

The current controller 39 inputs the torque current deviation from the subtractor 38, performs current control by PI control using preset proportional gain and integral gain so that the torque current deviation becomes 0, and outputs the torque voltage command Calculate V _q ^* . The current controller 39 then outputs the torque voltage command V _q ^* to the coordinate conversion section 13 .

Here, in the initial mode when the power is turned on, the current controller 39 calculates the torque voltage command V _q ^* = 0 by current control based on the torque current command i _q ^* = 0, and the torque voltage command V _q ^* = 0 is output to the coordinate transformation unit 13 .

Then, when the initial mode is switched to the operation mode, the current controller 39 outputs the torque voltage command V _q ^* calculated by the current control based on the torque current command i _q ^* to the coordinate conversion section 13 in the operation mode.

Thus, according to the torque control unit 11, in the initial mode when the power is turned on, the speed controller 33 converts the gain lower limit value K _Vmin generated using speed feedback ω=0 to the gain K _V to generate a torque command T ^* =0 with little change. Multiplier 37 similarly generates a torque current command i _q ^* =0 with little change. Then, the current controller 39 outputs the torque voltage command V _q ^* =0 generated by the current control and having little change to the coordinate conversion section 13 . DC excitation is thereby performed.

Also, in the operation mode, the speed controller 33 performs speed control using the normal gain K _V ^* as the gain K _V to generate the torque command T ^* , and the multiplier 37 generates the torque current command i _q ^* . Then, the current controller 39 outputs the torque voltage command V _q ^* generated by the current control to the coordinate conversion section 13 . As a result, normal motor control is performed.

[Electrical angle control unit 12]
Next, the electrical angle control section 12 shown in FIG. 1 will be described in detail. As described above, the electrical angle control unit 12 outputs the electrical angle θ _e =0 to the coordinate conversion units 13 and 14 in the initial mode when the power is turned on, and the electrical angle θ _e calculated from the speed feedback ω in the operation mode. are output to the coordinate transformation units 13 and 14 .

FIG. 4 is a block diagram showing a configuration example of the electrical angle control section 12. As shown in FIG. The electrical angle control section 12 has a multiplier 40 , a filter 41 , a switch 42 and an integrator 43 .

Multiplier 40 receives speed feedback ω, multiplies speed feedback ω by a preset number of paired poles N _P to obtain electrical angular velocity ω _{e , and outputs electrical angular velocity ω e to} filter 41 and switch 42 .

The filter 41 receives the electrical angular velocity ω _e from the multiplier 40 as well as a predetermined velocity command ω ^* , filters the electrical angular velocity ω _e using the following equation, and outputs the electrical angular velocity command ω _e ^*. is calculated, and an electrical angular velocity command ω _e ^* is output to the switch 42 .
[Number 3]
ω _e ^* = (P ₀ ω ^*2 /(1 + P ₀ ω ^*2 )) ω _e (3)

The switch 42 receives the initial mode signal INIT@, the electrical angular velocity command ω _e ^* from the filter 41 , and the electrical angular velocity ω _e from the multiplier 40 .

When the switch 42 receives an initial mode signal INIT@=1 in the initial mode when the power is turned on, the switch 42 conducts the a-contact relay and disconnects the b-contact relay. The switch 42 outputs the electrical angular velocity command ω _e ^* input from the filter 41 to the integrator 43 .

When the switch 42 is switched from the initial mode to the operation mode and receives an initial mode signal INIT@=0, the a-contact relay is rendered non-conductive and the b-contact relay is rendered conductive. The switch 42 outputs the electrical angular velocity ω _e input from the multiplier 40 to the integrator 43 .

The integrator 43 receives the initial mode signal INIT@ and the electrical angular velocity command ω _e ^* or the electrical angular velocity ω _e from the switch 42 . The integrator 43 resets the counter at the timing when the initial mode signal INIT@ is input. The integrator 43 increments the counter by integrating the electrical angular velocity command ω _e ^* or the electrical angular velocity ω _e to obtain the electrical angle θ _{e and outputs the electrical angle θ e to} the coordinate conversion units 13 and 14 .

Here, in the initial mode when the power is turned on, the speed command ω ^* =0, so the filter 41 outputs the electrical angular speed command _ωe ^* =0 to the integrator 43 via the contact a of the switch 42. . In the initial mode when the power is turned on, the integrator 43 resets the counter when the initial mode signal INIT@=0 is input, receives the electrical angular velocity command ω _e ^* =0, and outputs the electrical angle θ _e =0. do. Thus, in the initial mode when the power is turned on, the electrical angle θ _e =0 is output to the coordinate conversion units 13 and 14, and DC excitation is performed.

Then, when the initial mode is switched to the operation mode, operation according to a predetermined speed pattern is started, and the speed command ω ^* >0 and the speed feedback ω>0. The multiplier 40 outputs the electrical angular velocity ω _e calculated from the velocity feedback ω to the integrator 43 via the contact b of the switch 42 . The integrator 43 receives the electrical angular velocity ω _e and outputs an electrical angle θ _e obtained from the electrical angular velocity ω _e . Accordingly, in the operation mode, the electrical angle θ _e calculated from the speed feedback ω is output to the coordinate conversion units 13 and 14, and the motor is controlled.

Thus, according to the electrical angle control unit 12, in the initial mode when the power is turned on, the filter 41 integrates the electrical angular velocity command ω _e ^* =0 generated using the fact that the speed command ω ^* =0. output to the device 43. The integrator 43 receives the electrical angular velocity command ω _e ^* =0 and outputs the electrical angle θ _e =0. As a result, coordinate conversion is performed by the coordinate conversion units 13 and 14 based on the electrical angle θ _e =0, and DC excitation is performed.

Also, in the operation mode, the integrator 43 receives the electrical angular velocity ω _e calculated from the velocity feedback ω, obtains the electrical angle θ _e , and outputs the electrical angle θ _e . As a result, the coordinate conversion units 13 and 14 perform coordinate conversion based on the electrical angle θ _e calculated from the speed feedback ω, and normal motor control is performed.

〔motion〕
Next, the DC excitation operation and the like in the initial mode when the power is turned on will be described. FIG. 5 is a time chart for explaining the operation of setting the magnetic pole phase δ to 0° by DC excitation. FIG. 5 shows speed command ω ^* , speed feedback ω, initial mode signal INIT@, DC exciting current command _i0 , exciting current command id ^* , torque current command _iq ^* , electrical angle _θe and magnetic pole phase δ. and the horizontal axis is time.

There are two operation modes for motor control by the motor control device 1: an initial mode when the power is turned on, and an operation mode in which control is performed according to a predetermined speed pattern. In the former initial mode, DC excitation is performed and the magnetic pole phase δ is set to 0°.

Referring to FIG. 5, when the power is turned on, the initial mode is entered and the initial mode signal INIT@=1 is set (a). At this time, it is assumed that the initial magnetic pole phase δ (initial phase) of the motor 3 is −90° (b). In the initial mode, speed command ω ^* =0 and speed feedback ω=0.

When the driving operation is performed in the initial mode (c), the DC excitation current command i0 is input to the DC excitation control unit 10 (d), and the excitation current command i _d ^* reflecting the DC excitation current command i0 is generated. (e). Then, an excitation voltage command V _d ^* is generated.

Also, in the torque control unit 11, since the speed command ω ^* =0 and the speed feedback ω=0, a torque current command _iq ^* =0 is generated (f). Then, a torque voltage command V _q ^* =0 is generated.

Also, in the electrical angle control unit 12, the electrical angle θ _e =0 is generated because the speed command ω ^* =0 and the speed feedback ω=0 (g).

As a result, in the coordinate conversion unit 13, based on the electrical angle θ _e =0, the excitation voltage command V _d ^* and the torque voltage command V _q ^* =0 reflecting the DC excitation current command i0 are converted into the U-phase AC voltage command V _u ^* , _V -phase AC voltage command Vv ^* , and _W -phase AC voltage command Vw ^* . Then, this three-phase AC voltage command is supplied to the power amplifier 2, and the magnetic pole phase .delta. of the motor 3 is set to 0.degree. (h).

On the other hand, when the initial mode is switched to the running mode, the initial mode signal INIT@=0 is set, the running mode is entered (i), the running according to the predetermined speed pattern is started, and the speed command ω ^* >0 (j) and the speed Feedback ω>0 (k).

In the DC excitation control unit 10, when the speed command ω ^* >0, an exciting current command i _d ^* =0 is generated (l) and an exciting voltage command V _d ^* =0 is generated.

Also, in the torque control unit 11, a torque current command i _q ^* is generated according to a speed deviation between the speed command ω ^* and the speed feedback ω, and a torque voltage command V _q ^* is generated.

Also, the electrical angle control unit 12 generates an electrical angle θ _e based on the speed feedback ω (m).

As a result, in the coordinate conversion unit 13, based on the electrical angle θ _e , the excitation voltage command V _d ^* =0 and the torque voltage command V _q ^* are changed from the U-phase AC voltage command V _u ^* and the V-phase AC voltage command V _v ^* and the W-phase AC voltage command V _w ^* . Then, this three-phase AC voltage command is supplied to the power amplifier 2, and the motor 3 is controlled.

〔simulation result〕
Next, computer simulation results by the motor control device 1 shown in FIG. 1 will be described. FIG. 6 is a diagram for explaining simulation results. From the top of the graph, velocity feedback ω, excitation current feedback _id , torque command T ^* , magnetic pole phase shift sin δ, and initial mode signal INIT@ are shown. The horizontal axis is time.

In the initial mode of the initial mode signal INIT@=1, when a driving operation is performed (a), the excitation current feedback _id changes from 0% to 50% with the torque command T ^* =0, and the DC excitation is stopped. know it will be done.

Then, the initial magnetic pole phase δ=-90° of the motor 3 is set to 0°, and the magnetic pole phase shift sin δ=-1 changes to zero.

On the other hand, when the initial mode is switched to the operation mode, in the operation mode with the initial mode signal INIT@=0, operation starts according to a predetermined speed pattern, the motor 3 is controlled, and the speed feedback ω changes from 0% to 100%. and return to 0%.

As described above, according to the motor control device 1 according to the embodiment of the present invention, in the initial mode when the power is turned on, the DC excitation control unit 10 uses the fact that the speed command ω ^* =0 to generate the excitation current command Generate i _d ^* = i0. Then, the DC excitation control unit 10 generates an excitation voltage command V _d ^* by current control based on the excitation current command _id ^* = i0.

On the other hand, in the operation mode, the DC excitation control unit 10 generates an excitation current command i _d ^* =0 by utilizing the fact that the speed command ω ^* >0, and a current based on the excitation current command i _d ^* =0. An excitation voltage command V _d ^* =0 is generated by control.

In the initial mode when the power is turned on, the torque control unit 11 generates a torque current command i _q ^* =0 by speed control using speed command ω ^* =0 and speed feedback ω=0. Then, the torque control unit 11 generates a torque voltage command V _q ^* =0 by current control based on the torque current command i _q ^* =0.

Here, the torque control unit 11 sets the gain K _v to the lower limit value by utilizing the fact that the speed feedback ω=0, and performs speed control. That is, the torque control unit 11 generates a torque current command i _q ^* =0 that changes little even if the speed feedback ω=0 changes to the speed feedback ω≠0. Then, the torque control unit 11 generates a torque voltage command V _q ^* =0 with little change.

Further, in the initial mode when the power is turned on, the torque control unit 11 sets the estimated load value TL^=0 by the load feedforward compensator 35, and the torque current command _iq ^* =0 which is not subjected to load feedforward compensation. to generate a torque voltage command V _q ^* =0.

On the other hand, in the operation mode, the torque control unit 11 generates a torque current command i _q ^* by speed control, and generates a torque voltage command V _q ^* by current control based on the torque current command i _q ^* .

In the initial mode when the power is turned on, the electrical angle control unit 12 utilizes the speed command ω ^* =0 to generate the electrical angle θ _e =0. Generate θ _e .

In the initial mode when the power is turned on, the coordinate conversion unit 13 converts the excitation voltage command V _d ^* and the torque voltage command V _q ^* = 0 based on the DC excitation current command i0 to the three-phase AC current command based on the electrical angle θ _e = 0. It converts it into a voltage command and outputs a three-phase AC voltage command to the power amplifier 2 .

As a result, AC voltage is supplied from the power amplifier 2 to the motor 3, and the magnetic pole phase δ of the motor 3 is set to 0°.

In the operation mode, the coordinate conversion unit 13 converts the excitation voltage command V _d ^* =0 and the torque voltage command V _q ^* into a three-phase AC voltage command based on the electrical angle θ _e generated from the speed feedback ω, A three-phase AC voltage command is output to the power amplifier 2 .

As a result, AC voltage is supplied from the power amplifier 2 to the motor 3, and the motor 3 is controlled.

Therefore, in the initial mode when the power is turned on, the magnetic pole phase .delta. of the motor 3 can be adjusted to 0.degree. Therefore, the absolute value encoder can be eliminated from the equipment for controlling the motor 3, and the cost can be reduced.

Although the present invention has been described above with reference to the embodiments, the present invention is not limited to the above embodiments, and can be variously modified without departing from the technical idea thereof. For example, in the embodiment, the motor 3 is PMSM in FIG. 1, but the present invention does not limit the motor 3 to PMSM. The motor 3 may be, for example, an IPM (Interior Permanent Magnet) motor or an SPM (Surface Permanent Magnet) motor. In short, the motor 3 should just be a PM motor.

1 motor controller 2 power amplifier 3 motor 4 PG (pulse generator)
10 DC excitation controller 11 Torque controller 12 Electrical angle controllers 13, 14 Coordinate converters 20, 31, 41 Filters 21, 30, 38 Subtractors 22, 39 Current controller 32 Limiter 33 Speed controllers 34, 37, 40 Multiplier 35 Load feedforward compensator 36 Adder 42 Switch 43 Integrator ω ^* Speed command ω Speed feedback
INIT@ initial mode signal i0 DC exciting current command i _d ^* exciting current command i _q ^* torque current command i _d exciting current feedback i _q torque current feedback i _u U phase AC current feedback i _v V phase AC current feedback i _w W phase AC current feedback V _d ^* exciting voltage command V _q ^* torque voltage command V _u ^* U-phase AC voltage command V _v ^* V-phase AC voltage command V _w ^* W-phase AC voltage command T ^* torque command K _V , K _V ^* , K _V ^* ' Gain K _Vmin Gain lower limit value K _T ^ Torque constant estimated value P ₀ threshold TL ^ Estimated load estimated value ω _e Electrical angular velocity ω _e ^* Electrical angular velocity command θ _e Electrical angle N _P Pair number of poles δ Magnetic pole phase sin δ Magnetic pole phase Misalignment

Claims (4)

An excitation voltage command is generated from the excitation current command, a torque voltage command is generated from the torque current command, an electrical angle is generated from the speed feedback of the PM motor, and the excitation voltage command and the torque voltage command are generated based on the electrical angle. is converted into a three-phase AC voltage command, and based on the three-phase AC voltage command, the PM motor is controlled via a power amplifier,
Filter processing based on a predetermined speed command is performed on a preset DC excitation current command to generate the excitation current command so that the excitation current deviation between the excitation current command and the excitation current feedback becomes zero. a DC excitation control unit that performs current control to generate the excitation voltage command;
Speed control is performed using a predetermined gain so that the speed deviation between the speed command and the speed feedback becomes 0, the torque current command is generated, and the difference between the torque current command and the torque current feedback is A torque control unit that performs current control so that the torque current deviation of is 0 and generates the torque voltage command;
generating an electrical angular velocity based on the velocity feedback, performing filtering on the electrical angular velocity based on the velocity command, generating an electrical angular velocity command, and selecting either one of the electrical angular velocity and the electrical angular velocity command; an electrical angle control unit that selects and performs integration processing to generate the electrical angle;
Based on the electrical angle generated by the electrical angle control section, the excitation voltage command generated by the DC excitation control section and the torque voltage command generated by the torque control section are converted into the three-phase AC voltage command. a first coordinate transformation unit that transforms into
Based on the electrical angle generated by the electrical angle control unit, three-phase alternating current feedback detected by a current detector provided between the power amplifier and the PM motor is applied to the excitation current feedback and the a second coordinate transformation unit that transforms to torque current feedback;
In the initial mode at power-on,
The DC excitation control unit is
The filtering process based on the zero-value speed command in the initial mode generates the excitation current command reflecting the DC excitation current command, and the current control reflects the DC excitation current command. generating the excitation voltage command;
The torque control section is
A preset gain lower limit value is set in the gain, and the 0 value torque current command is generated by the speed control using the gain lower limit value based on the 0 value speed command in the initial mode. and generating the torque voltage command of 0 value by the current control,
The electrical angle control unit
In the filtering process based on the 0-value speed command in the initial mode, the 0-value electrical angular velocity command is generated, the electrical angular velocity command is selected, the integration process is performed, and the 0° electrical angular velocity command is selected. A motor control device, characterized in that it generates an angle. The motor control device according to claim 1,
The DC excitation control unit is
Assuming that the DC excitation current command is i0, the speed command is ω ^* , a predetermined parameter is P0, and the excitation current command is id ^* , the formula: _id ^* ₌ (1/( ₁ + _P0ω ^*2 ))· at i0, a filter that performs the filtering process;
a subtractor that subtracts the excitation current feedback from the excitation current command generated by the filter to obtain the excitation current deviation;
and a current controller that performs the current control so that the excitation current deviation obtained by the subtractor becomes zero, and generates the excitation voltage command. The motor control device according to claim 1 or 2,
The torque control section is
a first subtractor that subtracts the speed feedback from the speed command to obtain the speed deviation;
Assuming that the preset gain is K _V ^* , the velocity feedback is ω, the predetermined parameter is P ₀ , and the gain after filtering is K _V ^* ', the formula: K _V ^* '=(P ₀ ω ² /(1+P ₀ ω ² ))·K _V ^* , a filter that performs filtering;
When the filtered gain generated by the filter is equal to or less than a preset threshold value, outputting the gain lower limit value, and outputting the preset gain value when the filtered gain is greater than the threshold value. a limiter that outputs gain;
A speed controller that performs the speed control using the gain lower limit value or the gain output by the limiter so that the speed deviation obtained by the first subtractor becomes 0, and generates the torque current command. When,
a second subtractor that subtracts the torque current feedback from the torque current command generated by the speed controller to determine the torque current deviation;
and a current controller that performs the current control so that the torque current deviation obtained by the second subtractor becomes zero, and generates the torque voltage command. In the motor control device according to any one of claims 1 to 3,
The electrical angle control unit
a multiplier that multiplies the velocity feedback by a preset number of opposite poles to generate the electrical angular velocity;
Assuming that the electrical angular velocity is ω _e , the speed command is ω ^* , a predetermined parameter is P ₀ , and the electrical angular velocity command is ω _e ^* , the formula: ω _e ^* = (P ₀ ω ^*2 /(1+P ₀ ω ^*2) )) · ω _e , a filter that performs the filtering process;
During the initial mode, the electrical angular velocity command generated by the filter is selected, the initial mode is switched to an operation mode, and during the operation mode, the electrical angular velocity generated by the multiplier is selected. a switch;
and an integrator that integrates the electrical angular velocity command or the electrical angular velocity selected by the switch to generate the electrical angle.

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