JP7046121B2 - Rotating machine control device - Google Patents

Description

The present application relates to a control device for a rotating machine.

In the technique of Patent Document 1, when a field current is passed at the start of an internal combustion engine, an armature current that forms a magnetic flux in the same direction as the field magnetic flux is passed to assist the formation of the field magnetic flux and magnetism. The response of the field current is increased by utilizing the decrease in inductance due to saturation.

In the technique of Patent Document 2, when the internal combustion engine is started, the d-axis current is passed in the positive direction in advance and then changed in the negative direction, whereby the mutual inductance between the armature winding and the field winding is changed. Causes a positive induced electromotive force in the field winding to increase the response of the field current.

JP-A-2002-191158. Japanese Unexamined Patent Publication No. 2018-42387

However, since the technique of Patent Document 1 is a control performed at the start of the internal combustion engine, it cannot be applied except at the start of the internal combustion engine.

In the technique of Patent Document 2, it is necessary to change the d-axis current to a positive value in advance before the output torque is generated, and under special conditions such as when the internal combustion engine is started, the output torque is not generated. Can only be executed.

The field current is constantly changed according to the change in the output torque, but the response delay of the field current causes the response delay of the rotor magnetic flux, and the response delay of the rotor magnetic flux causes the response delay of the output torque.

Therefore, an object of the present application is to provide a rotating machine control device capable of reducing the response delay of the rotor magnetic flux caused by the response delay of the field current without being limited to the start time of the internal combustion engine.

The rotary machine control device according to the present application is a rotary machine control device for controlling a rotary machine having a rotor provided with field windings and a stator provided with armature windings.
The armature current command value, which is the current command value of the armature winding, is calculated, the armature voltage command value is calculated based on the armature current command value, and the inverter is based on the armature voltage command value. An armature current control unit that applies a voltage to the armature winding by controlling the switching element to be turned on and off.
A field current detector that detects the field current flowing through the field winding,
The field current command value, which is the current command value of the field winding, is calculated, the field voltage command value is calculated based on the field current command value, and the converter is based on the field voltage command value. A field current control unit that applies a voltage to the field winding by controlling the switching element to be turned on and off is provided.
The direction of the magnetic poles of the rotor is defined as the d-axis, and the direction 90 ° ahead of the d-axis in terms of electrical angle is defined as the q-axis.
The armature current control unit changes the d-axis component of the armature current command value according to the deviation between the field current command value and the field current detection value .
When the armature current control unit reaches the maximum voltage saturation state in which the field voltage command value becomes equal to or higher than the maximum voltage that can be applied to the field winding, the armature current control unit determines the armature current command value according to the deviation. It changes the d-axis component.

According to the controller of the rotating machine according to the present application, even if the rotor current deviation deviates from the target rotor current due to the response delay of the field current, the deviation between the field current command value and the field current detection value is obtained. Since the d-axis component of the armature current command value is changed accordingly, the rotor magnetic flux can be changed by changing the d-axis component of the armature current command value, and the rotor magnetic flux can be brought closer to the target rotor magnetic flux. can. Therefore, the response delay of the rotor magnetic flux caused by the response delay of the field current can be reduced without being limited to the start time of the internal combustion engine, and the response delay of the output torque caused by the response delay of the rotor magnetic flux can be reduced. can.

It is a schematic block diagram of the rotary machine and the control device of the rotary machine which concerns on Embodiment 1. FIG. It is a schematic block diagram of the control device which concerns on Embodiment 1. FIG. It is a hardware block diagram of the control device which concerns on Embodiment 1. FIG. It is a time chart explaining the on / off control behavior of the switching element of the inverter which concerns on Embodiment 1. FIG. It is a time chart explaining the on / off control behavior of the switching element of the converter which concerns on Embodiment 1. FIG. It is a time chart explaining the control behavior which concerns on the comparative example of Embodiment 1. It is a time chart explaining the control behavior which concerns on the comparative example of Embodiment 1. It is a relationship characteristic diagram of the field current, the rotor magnetic flux, and the current differential inductance which concerns on Embodiment 1. FIG. It is a figure which shows the magnetic saturation characteristic of the rotor magnetic flux which concerns on Embodiment 1. It is a time chart explaining the control behavior which concerns on Embodiment 1. FIG. It is a time chart explaining the control behavior which concerns on Embodiment 1. FIG. It is a time chart explaining the control behavior which concerns on Embodiment 2. It is a time chart explaining the control behavior which concerns on the comparative example of Embodiment 3. It is a time chart explaining the control behavior which concerns on Embodiment 3. It is a time chart explaining the control behavior which concerns on the comparative example of Embodiment 3. It is a time chart explaining the control behavior which concerns on Embodiment 3. It is a schematic diagram of the rotary machine which was made into the generator motor for the vehicle which concerns on Embodiment 1. FIG.

1. 1. Embodiment 1
The control device 11 (hereinafter, simply referred to as the control device 11) of the rotary machine according to the first embodiment will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram of a rotary machine 1 and a control device 11 according to the present embodiment.

1-1. Rotating machine 1
The rotary machine 1 includes a stator 18 and a rotor 14 arranged radially inside the stator 18. The rotating machine 1 is a field winding type synchronous rotating machine. The armature winding 12 is wound around the iron core of the stator 18. A field winding 4 is wound around the iron core of the rotor 14, and an electromagnet is provided.

In the present embodiment, the armature winding 12 is a three-phase armature winding Cu, Cv, Cw of U phase, V phase, and W phase. The three-phase armature windings Cu, Cv, and Cw may be star-connected or delta-connected.

The rotor 14 is provided with a rotation sensor 15 that detects the rotation angle (rotation angle) of the rotor 14. The output signal of the rotation sensor 15 is input to the control device 11. As the rotation sensor 15, various sensors such as a Hall element, a resolver, or an encoder are used. The rotation sensor 15 may not be provided, and may be configured to estimate the rotation angle (pole position) based on the current information obtained by superimposing the harmonic component on the current command value described later (so-called). Sensorless method).

1-2. DC power supply 2
The DC power supply 2 outputs a DC voltage Vdc to the inverter 5 and the converter 9. As the DC power supply 2, any device that outputs a DC voltage, such as a battery, a DC-DC converter, a diode rectifier, and a PWM rectifier, is used. A smoothing capacitor 3 is connected in parallel to the DC power supply 2.

1-3. Inverter 5
The inverter 5 has a plurality of switching elements and performs power conversion between the DC power supply 2 and the armature winding 12. The inverter 5 is a series circuit in which a switching element SP on the positive electrode side connected to the positive electrode side of the DC power supply 2 and a switching element SN on the negative electrode side connected to the negative electrode side of the DC power supply 2 are connected in series. Three sets are provided corresponding to the armature winding of each phase. The connection points of the two switching elements in each series circuit are connected to the armature windings of the corresponding phase.

Specifically, in the U-phase series circuit, the switching element SPu on the positive electrode side of the U phase and the switching element SNu on the negative electrode side of the U phase are connected in series, and the connection point of the two switching elements is an armature of the U phase. It is connected to the winding Cu. In the V-phase series circuit, the switching element SPv on the positive electrode side of the V phase and the switching element SNv on the negative electrode side of the V phase are connected in series, and the connection point of the two switching elements is connected to the armature winding Cv of the V phase. Has been done. In the W-phase series circuit, the switching element SPw on the positive electrode side of W and the switching element SNw on the negative electrode side of W phase are connected in series, and the connection points of the two switching elements are connected to the armature winding Cw of W phase. ing.

As the switching element of the inverter 5, an IGBT (Insulated Gate Bipolar Transistor) in which diodes are connected in antiparallel, a bipolar transistor in which diodes are connected in antiparallel, a MOSFET (Metal Oxide Semiconductor Field Effect Transistor), and the like are used. The gate terminal of each switching element is connected to the control device 11 via a gate drive circuit or the like. Therefore, each switching element is turned on or off by the switching signal output from the control device 11.

The armature current sensor 8 is a current detection circuit that detects the current flowing through the armature windings Cu, Cv, and Cw of each phase. In the present embodiment, the armature current sensor 8 is provided on the electric wire connecting the series circuit of the switching element of each phase and the armature winding. The output signal of the armature current sensor 8 of each phase is input to the control device 11. The armature current sensor 8 is a current sensor such as a Hall element and a shunt resistor. The armature current sensor 8 may be connected in series to the series circuit of the switching element of each phase.

1-4. Converter 9
The converter 9 has a switching element and performs power conversion between the DC power supply 2 and the field winding 4. In the present embodiment, the converter 9 is a series in which the power semiconductor SP on the positive electrode side connected to the positive electrode side of the DC power supply 2 and the power semiconductor SN on the negative electrode side connected to the negative electrode side of the DC power supply 2 are connected in series. It is an H-bridge circuit with two sets of circuits. The connection point between the power semiconductor SP1 on the positive electrode side and the power semiconductor SN1 on the negative electrode side in the series circuit 28 of the first set is connected to one end of the field winding 4, and the power on the positive electrode side in the series circuit 29 of the second set. The connection point between the semiconductor SP2 and the power semiconductor SN2 on the negative electrode side is connected to the other end of the field winding 4.

In the present embodiment, the power semiconductor SP on the positive electrode side and the power semiconductor SN on the negative electrode side of the first set and the second set are switching elements. As the switching element of the converter 9, an IGBT in which diodes are connected in antiparallel, a bipolar transistor in which diodes are connected in antiparallel, a MOSFET, and the like are used. The gate terminal of each switching element is connected to the control device 11 via a gate drive circuit or the like. Therefore, each switching element is turned on or off by the switching signal output from the control device 11.

The converter 9 has other configurations such as replacing the switching element SN1 on the negative side of the series circuit 28 of the first set with a diode and replacing the switching element SN2 on the negative side of the negative side of the series circuit 29 of the second set with a diode. May be.

The field current sensor 6 is a current detection circuit that detects the field current If, which is the current flowing through the field winding 4. In the present embodiment, the field current sensor 6 is provided on the electric wire connecting the connection point of the series circuit 28 of the first set and one end of the field winding 4. The field current sensor 6 may be provided at another location where the field current If can be detected. The output signal of the field current sensor 6 is input to the control device 11. The field current sensor 6 is a current sensor such as a Hall element and a shunt resistor.

1-5. Control device 11
The control device 11 controls the rotary machine 1 via the inverter 5 and the converter 9. As shown in FIG. 2, the control device 11 includes functional units such as a rotation detection unit 31, an armature current detection unit 32, an armature current control unit 33, a field current detection unit 34, and a field current control unit 35. I have. Each function of the control device 11 is realized by the processing circuit provided in the control device 11. Specifically, as shown in FIG. 3, the control device 11 includes an arithmetic processing unit 90 (computer) such as a CPU (Central Processing Unit), a storage device 91 for exchanging data with the arithmetic processing unit 90, as a processing circuit. The arithmetic processing unit 90 includes an input circuit 92 for inputting an external signal, an output circuit 93 for outputting a signal from the arithmetic processing unit 90 to the outside, a communication circuit 94 for data communication with the external device, and the like.

The arithmetic processing device 90 is provided with an ASIC (Application Specific Integrated Circuit), an IC (Integrated Circuit), a DSP (Digital Signal Processor), an FPGA (Field Programmable Gate Array), various logic circuits, various signal processing circuits, and the like. You may. Further, as the arithmetic processing unit 90, a plurality of the same type or different types may be provided, and each processing may be shared and executed. As the storage device 91, a RAM (Random Access Memory) configured to be able to read and write data from the arithmetic processing unit 90, a ROM (Read Only Memory) configured to be able to read data from the arithmetic processing unit 90, and the like are used. It is prepared. The input circuit 92 is connected to various sensors and switches such as a rotation sensor 15, an armature current sensor 8, and a field current sensor 6, and A / D conversion in which the output signals of these sensors and switches are input to the arithmetic processing device 90. Equipped with vessels, etc. The output circuit 93 includes a drive circuit or the like to which an electric load such as a gate drive circuit for driving the switching elements of the inverter 5 and the converter 9 on and off is connected, and a control signal is output from the arithmetic processing device 90 to these electric loads. The communication circuit 94 communicates with an external device.

Then, in each function of the control units 31 to 35 included in the control device 11, the arithmetic processing unit 90 executes software (program) stored in the storage device 91 such as a ROM, and the storage device 91 and the input circuit 92. , And by cooperating with other hardware of the control device 11 such as the output circuit 93. The setting data such as table data used by each of the control units 31 to 35 and the like is stored in a storage device 91 such as a ROM as a part of software (program). Hereinafter, each function of the control device 11 will be described in detail.

1-5-1. Basic control of armature current The rotation detection unit 31 detects the magnetic pole position θ (rotation angle θ of the rotor) and the rotation angular velocity ω of the rotor at the electric angle. In the present embodiment, the rotation detection unit 31 detects the magnetic pole position θ (rotation angle θ) and the rotation angular velocity ω of the rotor based on the output signal of the rotation sensor 15. The magnetic pole position is set in the direction of the north pole of the electromagnet provided in the rotor. The rotation detection unit 31 is configured to estimate the rotation angle (pole position) based on the current information obtained by superimposing the harmonic component on the current command value without using the rotation sensor. It is also good (so-called sensorless method).

The armature current detection unit 32 detects the armature currents Iur, Ivr, and Iwr flowing in the three-phase windings based on the output signal of the armature current sensor 8. Here, Iur is the detected value of the U-phase armature current Iu, Ivr is the detected value of the V-phase armature current Iv, and Iwr is the detected value of the W-phase armature current Iw. .. The armature current sensor 8 may be configured to detect the two-phase armature current, and the remaining one-phase armature current may be calculated based on the detected value of the two-phase armature current. For example, the armature current sensor 8 may detect the V-phase and W-phase armature currents Ivr and Iwr, and the U-phase armature current Iur may be calculated by Iur = -Ivr-Iwr.

The armature current control unit 33 calculates the armature current command value, which is the current command value of the armature winding, calculates the armature voltage command value based on the armature current command value, and converts it into the armature voltage command value. Based on this, a voltage is applied to the armature winding by controlling the switching element of the inverter 5 on and off.

In the present embodiment, as shown in FIG. 2, the armature current control unit 33 includes a current command value calculation unit 331, a voltage command value calculation unit 332, and a switching control unit 333.

The current command value calculation unit 331 calculates the armature current command value. In the present embodiment, the current command value calculation unit 331 calculates the current command value Ido on the d-axis and the current command value Iqo on the q-axis. The d-axis is set in the direction of the magnetic poles (N pole, magnetic pole position θ) of the rotor, and the q-axis is set in the direction advanced by 90 ° in electrical angle from the d-axis. The rotating coordinate system of the dq axis rotates in synchronization with the rotation of the magnetic pole position θ of the rotor.

The current command value calculation unit 331 calculates the basic current command values Idob and Iqob of the d-axis and the q-axis according to known vector control methods such as maximum torque current control, field weakening control, and Id = 0 control. In the present embodiment, a case where the basic current command values Idob and Iqob of the d-axis and the q-axis are calculated by the maximum torque current control will be described.

In the maximum torque current control, the basic current command values Idob and Iqob of the d-axis and the q-axis that minimize the current for outputting the torque of the torque command value To are calculated.

In the field weakening control, the basic current command value Idob of the d-axis is increased in the negative direction from the basic current command values Idob and Iqob of the d-axis and the q-axis calculated by the maximum torque current control. In the weak magnetic flux control, the basic current command values Idob and Iqob of the dq axis are calculated at the intersection of the voltage limiting ellipse (constant induced voltage ellipse) and the constant torque curve of the torque command value To on the rotating coordinate system of the dq axis. Will be done.

In the Id = 0 control, the basic current command value Idob on the d-axis is set to 0, and the basic current command value Iqob on the q-axis is increased or decreased according to the torque command value To.

The torque command value To may be calculated inside the control device 11 or may be transmitted from the outside of the control device 11.

In the present embodiment, as shown in the following equation, the current command value calculation unit 331 receives a d-axis basic current command set according to the vector control method when the d-axis current change condition described later is not satisfied. The value Ido is set to the final d-axis current command value Ido. When the change condition of the d-axis current is satisfied, the current command value calculation unit 331 adds a value obtained by adding the change amount ΔIdo of the current command value of the d-axis, which will be described later, to the basic current command value Ido of the d-axis. Set to the final d-axis current command value Ido. In the present embodiment, it is assumed that the change condition of the d-axis current is always satisfied.
1) If the condition for changing the d-axis current is not satisfied,
Ido = Idob ... (1)
2) When the condition for changing the d-axis current is satisfied
Ido = Ido + ΔIdo

As shown in the following equation, the current command value calculation unit 331 sets the q-axis basic current command value Iqob set according to the vector control method to the final q regardless of whether or not the d-axis current change condition is satisfied. Set to the current command value Iqo of the shaft.
Iqo = Iqob ... (2)

The voltage command value calculation unit 332 calculates the armature voltage command value based on the armature current command value. In the present embodiment, the voltage command value calculation unit 332 calculates the voltage command values Vdo and Vqo of the d-axis and the q-axis based on the current command values Ido and Iqo of the d-axis and the q-axis.

The voltage command value calculation unit 332 performs three-phase two-phase conversion and rotational coordinate conversion on the three-phase armature current detection values Iur, Ivr, and Iwr based on the magnetic pole position θ, and the d-axis current detection value Idr. And converted to the current detection value Iqr on the q-axis. Then, the voltage command value calculation unit 332 sets the deviation ΔId between the d-axis current command value Ido and the d-axis current detection value Idr so that the d-axis current detection value Idr approaches the d-axis current command value Ido. On the other hand, proportional integration control is performed to calculate the voltage command value Vdo on the d-axis, and the current command values Iqo on the q-axis and the current command value Iqo on the q-axis so that the current detection value Iqr on the q-axis approaches the current command value Iqo on the q-axis. The voltage command value Vqo on the q-axis is calculated by performing proportional integration control with respect to the deviation ΔIq from the current detection value Iqr. Further, a known feedforward control for non-interference between the d-axis current and the q-axis current may be performed.

Alternatively, the voltage command value calculation unit 332 does not use the current detection value, but uses the specifications of the rotating machine based on the d-axis and q-axis current command values Ido and Iqo, and uses the d-axis and q-axis voltage command values. Feed forward control for calculating Vdo and Vqo may be executed. For example, as shown in the following equation, the voltage command value calculation unit 332 has the specifications of the rotating machine (winding resistance value R, d-axis inductance Ld) based on the d-axis and q-axis current command values Ido and Iqo. , Q-axis inductance Lq, rotor magnetic flux ψf), and rotation angle velocity ω, the voltage command value Vdo on the d-axis and the voltage command value Vqo on the q-axis may be calculated. In this case, the armature current sensor 8 and the armature current detection unit 32 may not be provided.
Vdo = R x Ido-ω x Lq x Iqo
Vqo = R × Iqo + ω × (Ld × Ido + ψf) ・ ・ ・ (3)

Then, the voltage command value calculation unit 332 performs fixed coordinate conversion and two-phase three-phase conversion on the d-axis and q-axis voltage command values Vdo and Vqo based on the magnetic pole position θ, and performs three-phase voltage command values. Convert to Vuo, Vvo, Vwo. The voltage command value calculation unit 332 may apply modulation such as two-phase modulation and space vector modulation so that the line voltage does not change with respect to the three-phase voltage command value.

The switching control unit 333 applies a voltage to the armature winding by controlling the switching element of the inverter 5 on and off by PWM control (Pulse Width Modulation) based on the armature voltage command value. In the present embodiment, as shown in FIG. 4, the switching control unit 333 compares each of the three-phase voltage command values Vuo, Vvo, and Vwo with the armature carrier Cs vibrating at the period Tss of the armature carrier. This controls on / off of a plurality of switching elements. The armature carrier wave Cs is a triangular wave that oscillates with an amplitude of Vdc / 2, which is half the DC voltage, centered on 0 in the period Tss of the armature carrier wave. The DC voltage Vdc may be detected by a voltage sensor.

When the armature carrier Cs falls below the voltage command value for each phase, the switching control unit 333 turns on the switching signal QP of the switching element on the positive side (1 in this example), and the switching element on the positive side. When the armature carrier Cs exceeds the voltage command value, the switching signal QP of the switching element on the positive side is turned off (0 in this example), and the switching element on the positive side is turned off. On the other hand, when the armature carrier Cs falls below the voltage command value for each phase, the switching control unit 333 turns off the switching signal QN of the switching element on the negative electrode side (0 in this example) on the negative electrode side. When the switching element is turned off, the switching element on the negative electrode side is turned off, and the armature carrier Cs exceeds the voltage command value, the switching signal QN of the switching element on the negative electrode side is turned on (1 in this example). , Turn on the switching element on the negative electrode side. For each phase, between the on-period of the switching element on the positive electrode side and the on-period of the switching element on the negative electrode side, a short-circuit prevention period (dead time) in which both the switching element on the positive electrode side and the switching element on the negative electrode side are turned off. May be provided.

1-5-2. Basic control of field current The field current detection unit 34 detects the field current Ifr, which is the current flowing through the field winding 4, based on the output signal of the field current sensor 6. Here, Ifr is a detected value of the field current If.

The field current control unit 35 calculates the field current command value Ifo, which is the current command value of the field winding, calculates the field voltage command value Vfo based on the field current command value Ifo, and calculates the field voltage. A voltage is applied to the field winding 4 by controlling the switching element of the converter 9 on and off based on the command value Vfo.

In the present embodiment, as shown in FIG. 2, the field current control unit 35 includes a current command value calculation unit 351, a voltage command value calculation unit 352, and a switching control unit 353.

The current command value calculation unit 351 calculates the field current command value Ifo. For example, the current command value calculation unit 351 sets the field current command value Ifo based on the torque command value To or the like.

The voltage command value calculation unit 352 calculates the field voltage command value Vfo based on the field current command value Ifo. As shown in the following equation, the voltage command value calculation unit 352 performs proportional integral control with respect to the deviation ΔIf between the field current command value Ifo and the field current detection value Ifr (hereinafter referred to as field current deviation ΔIf). This is done to calculate the field voltage command value Vfo.

Here, Kpf is a proportional gain, Kif is an integral gain, s is a Laplace operator, and 1 / s represents an integral. The proportional gain Kpf and the integrated gain Kif may be changed according to the field current detection value Ifr, the d-axis current (command value or detection value), and the like. Although the equation (4) is represented by a continuous system, in reality, the arithmetic processing is executed for each arithmetic cycle using the arithmetic expression in which the equation (4) is discretized in the arithmetic cycle. In the present embodiment, the calculation period is set to be the same as the period Tsf of the field carrier wave described later.

Alternatively, the voltage command value calculation unit 352 executes feed forward control for calculating the field voltage command value Vfo using the specifications of the rotating machine based on the field current command value Ifo without using the current detection value. You may. For example, the voltage command value calculation unit 352 has a field voltage based on the specifications of the rotating machine (resistance value Rf of the field winding 4) based on the field current command value Ifo as shown in the following equation. The command value Vfo may be calculated. At this time, as shown in the following equation, a primary advance process may be added. Here, Tfo is a constant of linear advance processing, and s is a Laplace operator. The constant Tfo of the primary lead processing may be changed according to the field current detection value Ifr or the like. In this case, the field current sensor 6 and the field current detection unit 34 may not be provided.
Vfo = (Tfo × s + 1) × Rf × Ifo ・ ・ ・ (5)

As shown in the following equation, the voltage command value calculation unit 352 limits the field voltage command value Vfo to the upper limit by the upper limit voltage value Vfmax, and limits the field voltage command value Vfo to the lower limit by the lower limit voltage value Vfmin. Here, MIN (A, B) is a function that outputs whichever of A and B is smaller. MAX (A, B) is a function that outputs whichever of A and B is larger.
Vfo = MAX (Vfmin, MIN (Vfmax, Vfo)) ... (6)

The upper limit voltage value Vfmax is set to the maximum voltage that can be applied to the field winding 4. The lower limit voltage value Vfmin is set to the minimum voltage that can be applied to the field winding 4. In the present embodiment, the upper limit voltage value Vfmax is set to the DC voltage Vdc. The lower limit voltage value Vfmin is set to -1 × DC voltage Vdc. The upper limit voltage value Vfmax may be set to a value smaller than the DC voltage Vdc in consideration of the influence of ringing immediately after switching, the setting of the short circuit prevention period described later, and the lower limit voltage value Vfmin is -1 × DC. It may be set to a value larger than the voltage Vdc.

The voltage command value calculation unit 352 does not have to limit the field voltage command value Vfo by the upper limit voltage value Vfmax and the lower limit voltage value Vfmin. In this way, even if the upper limit limit and the lower limit limit are not performed, as will be described later, the field voltage command value Vfo is a field carrier signal that oscillates between the maximum voltage (Vdc) and the minimum voltage (-Vdc). Since it is compared with Cf, the on / off control result of the switching element of the converter 9 is the same regardless of the presence or absence of the upper limit limit and the lower limit limit.

The switching control unit 353 controls the switching element of the converter 9 on and off by PWM control (Pulse Width Modulation) based on the field voltage command value Vfo.

For example, as shown in FIG. 5, the switching control unit 353 turns on and off a plurality of switching elements by comparing the field voltage command value Vfo with the field carrier signal Cf vibrating at the period Tsf of the field carrier. Control. The field carrier signal Cf is a triangular wave that oscillates between -1 × DC voltage Vdc and DC voltage Vdc at the period Tsf of the field carrier. The DC voltage Vdc may be detected by a voltage sensor.

When the field carrier signal Cf falls below the field voltage command value Vfo, the switching control unit 353 turns on the switching signal QP1 of the switching element SP1 on the positive electrode side of the first set (1 in this example), and the first The switching signal QN1 of the switching element SN1 on the negative electrode side of one set is turned off (0 in this example), the switching signal QP2 of the switching element SP2 on the positive electrode side of the second set is turned off (0), and the negative electrode of the second set. The switching signal QN2 of the switching element SN2 on the side is turned on (1).

On the other hand, when the field carrier signal Cf exceeds the field voltage command value Vfo, the switching control unit 353 turns off (0) the switching signal QP1 on the positive electrode side of the first set, and turns off (0) the switching signal QP1 on the negative electrode side of the first set. The switching signal QN1 is turned on (1), the switching signal QP2 on the positive electrode side of the second set is turned on (1), and the switching signal QN2 on the negative electrode side of the second set is turned off (0). For each set, between the on period of the switching element on the positive electrode side and the on period of the switching element on the negative electrode side, a short circuit prevention period (dead time) in which both the switching element on the positive electrode side and the switching element on the negative electrode side are turned off. May be provided.

1-5-3. Control of change in d-axis current according to field current deviation ΔIf <Control behavior of comparative example>
6 and 7 show the control behavior according to the comparative example when the torque command value To increases stepwise. In the comparative example, the change control of the d-axis current according to the field current deviation ΔIf described later is not performed, and the basic current command value Idob of the d-axis becomes the final current command value Ido of the d-axis as it is. Set. In FIG. 6, the increase amount of the field voltage command value Vfo is small, the field voltage command value Vfo does not reach the maximum voltage (upper limit voltage value Vfmax), and the maximum voltage saturation state is not reached. On the other hand, in FIG. 7, the increase amount of the field voltage command value Vfo is large, the field voltage command value Vfo reaches the maximum voltage (upper limit voltage value Vfmax), and the maximum voltage is saturated.

First, FIG. 6 will be described. The vertical axis of each graph shows the physical quantity dimensionless. The field voltage represents the maximum voltage that can be applied by 1.

At time t01, the torque command value To increases stepwise from 0. Then, the field current command value Ifo calculated according to the torque command value To increases stepwise from 0. Further, according to the torque command value To, the q-axis current command value Iqo calculated by the maximum torque current control increases stepwise from 0, and the d-axis current command value Ido decreases stepwise from 0. is doing.

The output torque Tr is proportional to the multiplication value of the rotor magnetic flux ψ and the q-axis current Iq. The rotor magnetic flux ψ changes according to the field current If. The responsiveness of the field current feedback control system is slower than the responsiveness of the d-axis and q-axis current feedback control systems. Therefore, the field current detection value Ifr changes later than the d-axis and q-axis current detection values Idr and Iqr. Therefore, the response delay of the output torque Tr is mainly caused by the response delay of the field current If.

Immediately after time t01, the decrease in the rotor magnetic flux due to the decrease in the current detection value Idr on the d-axis exceeded the increase in the rotor magnetic flux due to the increase in the field current detection value Ifr, so that the rotor magnetic flux temporarily decreased. , The output torque Tr is temporarily reduced.

At time t01, the field current deviation ΔIf between the field current command value Ifo and the field current detection value Ifr increases, and the field voltage command value Vfo calculated by PI control (particularly, the proportional term) increases. There is. However, the amount of increase in the field voltage command value Vfo is small, and the field voltage command value Vfo is not limited by the upper limit voltage value Vfmax. Therefore, the responsiveness of the field current feedback control system is not impaired, and the field current detection value Ifr follows the field current command value Ifo with the responsiveness (time constant) of the feedback control system. ..

Next, FIG. 7 will be described. Similar to FIG. 6, the vertical axis of each graph represents the physical quantity in a dimensionless manner. The field voltage represents the maximum voltage that can be applied by 1.

At time t11, as in FIG. 6, the torque command value To increases stepwise from 0, the field current command value Ifo increases stepwise from 0, and the q-axis current command value Iqo increases from 0. It increases stepwise, and the current command value Ido on the d-axis decreases stepwise from 0. However, since the increase in the torque command value To is larger than that in FIG. 6, the increase in the field current command value Ifo, the increase in the current command value Iqo on the q-axis, and the current command value Ido on the d-axis are large. The amount of decrease is large.

Therefore, the field current deviation ΔIf is larger than that in FIG. 6, and the field voltage command value Vfo calculated by PI control (particularly, the proportional term) is larger. The field voltage command value Vfo is limited by the upper limit voltage value Vfmax and is in the maximum voltage saturation state (from time t11 to time t12). Therefore, the responsiveness of the field current feedback control system is impaired, and the field current detection value Ifr responds to the field current command value Ifo slower than the original responsiveness (time constant) of the feedback control system. Follow by sex. Therefore, the response delay of the field current detection value Ifr is large, and the response delay of the rotor magnetic flux ψ and the output torque Tr that change according to the field current detection value Ifr is large.

As described above, in the comparative example, the response delay of the rotor magnetic flux ψ and the output torque Tr is caused by the response delay of the feedback control system of the field current. In particular, when the field voltage command value Vfo reaches the maximum voltage (upper limit voltage value Vfmax) in the maximum voltage saturation state, or when the field voltage command value Vfo reaches the minimum voltage (lower limit voltage value Vfmin), the minimum voltage saturation state is reached. , The responsiveness of the field current feedback control system deteriorates, and the responsiveness of the rotor magnetic flux ψ and the output torque Tr deteriorates.

<Responsiveness of field winding>
The voltage equation of the field winding can be expressed by the following equation. Here, ψ is the magnetic flux of the iron core of the rotor, Rf is the resistance of the field winding, and Vf is the applied voltage of the field winding.

By transforming equation (7), the following equation is obtained. Here, the current differential inductance dLIf is obtained by differentiating the rotor magnetic flux ψ with respect to the field current If. The current differential inductance dLIf can also be expressed as the ratio of the change in the rotor magnetic flux ψ to the change in the field current If at each operating point of the field current If.

When the equation (8) is transformed by Laplace transform, the transfer function Gpf (s) of the field winding becomes as follows.

As shown in the equation (9), the responsiveness (time constant) of the transfer function Gpf (s) of the field winding to be controlled is proportional to the current differential inductance dLIf. Therefore, by reducing the current differential inductance dLIf, the responsiveness of the field winding to be controlled can be improved.

<Improvement of responsiveness of rotor magnetic flux ψ due to change in d-axis current>
As shown in the upper part of FIG. 8, under the condition of d-axis current Id = 0, in the region where the field current If is smaller than the operating point A, the rotor is not magnetically saturated and is proportional to the field current If. Therefore, the rotor magnetic flux ψ is increasing, and the current differential inductance dLIf is a constant value. On the other hand, when the field current If becomes larger than the operating point A, magnetic saturation occurs in the iron core of the rotor, and the slope of the increase in the rotor magnetic flux ψ with respect to the increase in the field current If decreases. Here, the rotor magnetic flux ψ is a d-axis component of the rotor magnetic flux. Therefore, as shown in the lower part of FIG. 8, the current differential inductance dLIf obtained by differentiating the rotor magnetic flux ψ with respect to the field current If decreases as the field current If increases from the operating point A.

<Theoretical rotor magnetic flux ψ0 and actual magnetic flux ψ due to magnetic saturation>
The theoretical rotor magnetic flux ψ0 when magnetic saturation does not occur is the magnetic flux obtained by multiplying the theoretical field winding inductance Lf0 by the field current If, and the theoretical d-axis inductance Ld0, as shown in the following equation. The magnetic flux obtained by multiplying the d-axis current Id by the d-axis current Id is the total magnetic flux. Here, the theoretical inductance Lf0 of the field winding is an inductance corresponding to the number of turns of the field winding (square of the number of turns), and the theoretical d-axis inductance Ld0 is the number of turns of the armature winding (the number of turns of the armature winding). It is the inductance according to the square of the number of turns).
ψ0 = Lf0 × If + Ld0 × Id ・ ・ ・ (10)

However, as shown in the following equation and FIG. 9, when magnetic saturation occurs, the actual rotor magnetic flux ψ decreases from the theoretical magnetic flux ψ0 when magnetic saturation does not occur. fψ () is a function representing the magnetic saturation characteristic of the iron core of the rotor.
ψ = fψ (ψ0) ・ ・ ・ (11)

<Translation of magnetic flux ψ according to d-axis current>
The following equation is obtained by modifying the equation (10).
ψ0 = Lf0 × (If + Ksr × Id)
Ksr = Ld0 / Lf0 ... (12)
Here, Ksr is a conversion constant that converts the d-axis current Id into a value equivalent to the field current. The conversion constant Ksr is the ratio of the d-axis inductance Ld0 according to the number of turns of the armature winding to the inductance Lf0 of the field winding corresponding to the number of turns of the field winding.

As shown in the equation (12), the field current If that the theoretical magnetic flux ψ0 has the same value changes according to the value obtained by multiplying the d-axis current Id by −Ksr. As shown in Equation (11) and FIG. 9, the actual magnetic flux ψ corresponding to the theoretical magnetic flux ψ0 of the same value has the same value. Therefore, as shown in FIG. 8, the characteristics of the actual rotor magnetic flux ψ and the current differential inductance dLIf are in the direction (horizontal direction) of the field current If according to the value obtained by multiplying the d-axis current Id by −Ksr. Move in parallel.

<Change in d-axis current to obtain the target rotor magnetic flux ψo>
Consider setting the d-axis current Id to obtain the target rotor magnetic flux ψo. For example, in FIG. 8, the rotor magnetic flux ψ at the field current command value Ifo and the basic current command value Idob of the d-axis is set as the target rotor magnetic flux ψo. The target current differential inductance dLIfo is set corresponding to the target rotor magnetic flux ψo. From the equation (12), when the field current If is the field current command value Ifo and the d-axis current Id is the basic current command value Idob of the d-axis, the theoretical target rotor magnetic flux ψo0 is as follows. It becomes an expression.
ψo0 = Lf0 × (Ifo + Ksr × Idob) ・ ・ ・ (13)

Then, in the current field current detection value Ifr, assuming that the current command value of the d-axis after the change for obtaining the theoretical target rotor magnetic flux ψo0 is Idochg, the following equation is obtained from the equation (12).
ψo0 = Lf0 × (Ifr + Ksr × Idochg) ・ ・ ・ (14)

By substituting the equation (14) into the equation (13) and rearranging the current command value Idochg on the d-axis after the change, the following equation is obtained. Here, ΔIdo is the amount of change in the current command value on the d-axis.
Idochg = Idob + ΔIdo
ΔIdo = (Ifo-Ifr) / Ksr ... (15)

Therefore, even if the rotor magnetic flux ψ deviates from the target rotor magnetic flux ψo corresponding to the field current command value Ifo and the basic current command value Idob of the d-axis due to the response delay of the field current, the current command value of the d-axis By changing Ido by the amount of change ΔIdo of the current command value of the d-axis according to the field current deviation ΔIf (= Ifo-Ifr), the rotor magnetic flux ψ can be brought closer to the target rotor magnetic flux ψo.

Therefore, the armature current control unit 33 changes the current command value Ido on the d-axis according to the deviation between the field current command value Ifo and the field current detection value Ifr (field current deviation ΔIf).

In the present embodiment, the armature current control unit 33 calculates the change amount ΔIdo of the current command value of the d-axis by using the equation (15), and the change amount ΔIdo of the current command value of the d-axis is used for the d-axis. The current command value Ido is changed. In the present embodiment, as described using the equation (1), the armature current control unit 33 is a value obtained by adding the change amount ΔIdo of the current command value of the d-axis to the basic current command value Idob of the d-axis. Is set to the final d-axis current command value Ido. In the present embodiment, it is assumed that the change condition of the d-axis current is always satisfied.

The response delay of the rotor magnetic flux to the target rotor magnetic flux ψo corresponding to the field current command value Ifo and the basic current command value Idob of the d-axis caused by the response delay of the field current detection value Ifr with respect to the field current command value If. It can be reduced by the change of the rotor magnetic flux caused by the change of the d-axis current. Therefore, it is possible to reduce the response delay of the output torque caused by the response delay of the rotor magnetic flux. Further, similarly to the rotor magnetic flux, the response delay of the current differential inductance dLIf can be reduced, and the fluctuation of the responsiveness of the feedback control system of the field current can be reduced. In particular, even if the field voltage command value Vfo reaches the maximum voltage (upper limit voltage value Vfmax) in the maximum voltage saturation state, the responsiveness of the feedback control system deteriorates, and the field current deviation ΔIf becomes large, the field is magnetic. By changing the d-axis current according to the current deviation ΔIf, it is possible to reduce the response delay of the rotor magnetic flux and the response delay of the output torque caused by the response delay of the rotor magnetic flux. Further, the response delay of the current differential inductance dLIf can be reduced, and the deterioration of the responsiveness of the field current feedback control system can be suppressed.

<Control behavior>
10 and 11 show the control behavior according to the present embodiment in which the change processing of the current command value of the d-axis is performed under the same conditions as those of FIGS. 6 and 7 of the comparative example. Similar to FIGS. 6 and 7, the vertical axis of each graph represents the physical quantity in a dimensionless manner. The field voltage represents the maximum voltage that can be applied by 1.

First, FIG. 10 will be described. At time t21, the torque command value To increases stepwise from 0, the field current command value Ifo increases stepwise from 0, and the q-axis current command value Iqo increases from 0, as in FIG. It increases stepwise, and the basic current command value Idob on the d-axis decreases stepwise from 0.

Since the field current deviation ΔIf increased after the time t21, the amount of change ΔIdo of the current command value on the d-axis according to the field current deviation ΔIf increased, and the current command value Ido on the d-axis stepped at time t21. It is increased from the basic current command value Idob of the d-axis which has decreased to. Due to the increase in the d-axis current, the rotor magnetic flux is brought closer to the target rotor magnetic flux corresponding to the field current command value Ifo and the d-axis basic current command value Idob. Therefore, the output torque Tr does not decrease as shown in FIG. 6, and the response delay of the output torque Tr can be reduced.

Next, FIG. 11 will be described. At time t31, as in FIG. 7, the torque command value To increases stepwise from 0, the field current command value Ifo increases stepwise from 0, and the current command value Iqo on the q-axis increases from 0. It increases stepwise, and the basic current command value Idob on the d-axis decreases stepwise from 0.

As in FIG. 7, since the amount of increase in the torque command value To is large, the field voltage command value Vfo is limited by the upper limit voltage value Vfmax and is in the maximum voltage saturation state (time from time t31). Up to t32).

After the time t31, since the field current deviation ΔIf increased, the amount of change ΔIdo of the current command value of the d-axis increased, and the current command value Ido of the d-axis decreased stepwise at the time t31, the basic current of the d-axis. It is more than the command value Idob. Due to the increase in the d-axis current, the rotor magnetic flux is brought closer to the target rotor magnetic flux corresponding to the field current command value Ifo and the d-axis basic current command value Idob. Therefore, the responsiveness at the rising edge of the output torque Tr is better than that in FIG. 7, and the response delay of the output torque Tr is reduced as a whole.

The inductance of the field winding is larger than the inductance of the armature winding. The response frequency of the field current feedback control system from the field current command value Ifo to the field current detection value Ifr is the current command value Ido on the d-axis and q-axis and the current detection value Idr on the d-axis and q-axis from Iqo. , It is set lower than the response frequency of the feedback control system of the armature current up to Iqr. Here, the response frequency corresponds to the cutoff frequency of the closed loop transfer function and the reciprocal of the time constant. Therefore, the rate of increase of the d-axis current is faster than the rate of increase of the field current. By increasing the current command value of the d-axis, the d-axis current can be rapidly increased and the rotor magnetic flux can be increased.

Further, due to the increase in the d-axis current, the current differential inductance dLIf is brought closer to the target current differential inductance corresponding to the field current command value Ifo and the d-axis basic current command value Idob. Therefore, it is possible to reduce the deterioration of the responsiveness of the field current feedback control system due to the maximum voltage saturation state, and it is possible to improve the responsiveness of the field current detection value Ifr as compared with FIG. 7. Therefore, as compared with FIG. 7, the field current deviation ΔIf can be reduced with good responsiveness, the maximum voltage saturation state can be eliminated at an early stage, and the deterioration of the responsiveness of the feedback control system can be eliminated. Therefore, even when the maximum voltage saturation state occurs, the response delay of the field current detection value Ifr and the output torque Tr can be reduced. When ΔIdo becomes negative, the rotor magnetic flux is reduced and the inductance is increased as shown in FIG. 8, and the response time constant by the circuit becomes large. Therefore, the rotor magnetic flux is increased by setting ΔIdo to 0 or more. Inductance can be reduced.

<Increase in q-axis current command value>
On the other hand, as shown in FIGS. 10 and 11, the rotor magnetic flux is brought closer to the target rotor magnetic flux corresponding to the field current command value Ifo and the d-axis basic current command value Idob due to the increase in the d-axis current. However, the output torque Tr is not sufficiently increased with respect to the torque command value To. This is because the reluctance torque decreases by increasing the d-axis current.

The output torque Tr of the rotating machine is given by the following equation. Here, Pm is the pole logarithm, ψ is the rotor magnetic flux (d-axis component) described above, and Lq is the q-axis inductance. In a rotating machine in which reluctance torque is generated, Ld <Lq and (Ld-Lq) <0 in many cases.
Tr = Pm × Iq × {Lf × If + (Ld-Lq) × Id}
= Pm × Iq × {ψ-Lq × Id}
= Pm × Iq × {ψ-Lq × (Idob + ΔIdo)} ・ ・ ・ (16)

ここで、ΔＩｑｏは、ｑ軸の電流指令値の変化量であり、Ｔｏは、トルク指令値である。 The d-axis rotor magnetic flux ψ of the equation (16) becomes the target rotor magnetic flux due to the increase in the d-axis current. On the other hand, the rotor magnetic flux on the q-axis decreases by Lq × ΔIdo due to the increase in the d-axis current, and the output torque decreases by Pm × Iq × Lq × ΔIdo. Therefore, as shown in the following equation, if the q-axis current Iq is changed so as to compensate for the change in output torque Pm × Iq × Lq × ΔIdo, the change in output torque can be suppressed.

Here, ΔIqo is the amount of change in the current command value of the q-axis, and To is the torque command value.

Therefore, the armature current control unit 33 may change the current command value Iqo on the q-axis according to the change amount ΔIdo of the current command value on the d-axis. For example, the armature current control unit 33 calculates the change amount ΔIqo of the current command value of the q-axis using the equation (17) for each calculation cycle during the period when the change condition of the d-axis current is satisfied, and q. The value obtained by adding the change amount ΔIqo of the current command value of the q-axis to the basic current command value Iqo of the shaft is set as the final current command value Iqo of the q-axis.

<When used as a generator motor for vehicles>
When the control device for the rotary machine of the present embodiment is used for a generator motor for a vehicle, the configuration is as shown in FIG. The rotary shaft of the rotor of the rotary machine 1 is connected to the crank shaft of the internal combustion engine 100 via a pulley and a belt mechanism 101. The rotating shaft of the rotating machine 1 is connected to the wheel 103 via the internal combustion engine 100 and the transmission 102. The rotary machine 1 functions as an electric motor, serves as a driving force source for the wheels 103 as an auxiliary machine of the internal combustion engine 100, and also functions as a generator, and generates electricity by utilizing the rotation of the internal combustion engine 100.

In recent years, the number of idle-stop vehicles has increased, and there is a demand for shortening the rise time of the drive torque when the internal combustion engine is restarted by the drive torque of the rotary machine 1. When the rise time of the field current is delayed in the control device of the rotary machine, the rise time of the drive torque and the rise time of the power generation are delayed. As described above, by changing the d-axis current according to the field current deviation ΔIf, it is possible to reduce the response delay of the rotor magnetic flux and the output torque due to the response delay of the field current.

2. 2. Embodiment 2
Next, the rotary machine 1 and the control device 11 according to the second embodiment will be described. The description of the same components as those in the first embodiment will be omitted. The basic configuration of the rotary machine 1 and the control device 11 according to the present embodiment is the same as that of the first embodiment, but the method of setting the change condition of the d-axis current is different from that of the first embodiment.

In the present embodiment, the armature current control unit 33 is in a maximum voltage saturation state where the field voltage command value Vfo is equal to or higher than the maximum voltage (upper limit voltage value Vfmax) that can be applied to the field winding. It is determined that the change condition of the shaft current is satisfied, and the current command value Ido of the d-axis is changed according to the field current deviation ΔIf.

As described above with reference to FIGS. 7 and 11, when the maximum voltage is saturated, the response delay of the field current becomes large, and the response delay of the rotor magnetic flux and the output torque becomes large. Therefore, the field current deviation ΔIf. By changing the current command value Ido of the d-axis according to the above, the response delay of the rotor magnetic flux, the output torque, and the field current can be reduced.

The armature current control unit 33 determines that the d-axis current change condition is no longer satisfied when the following equation is satisfied after the maximum voltage saturation state is reached and the d-axis current change condition is satisfied, and the d-axis current control unit 33 determines that the d-axis current change condition is no longer satisfied. Ends the process of changing the current command value of.
Ifr + Idob × Ksr ≧ Ifsat 0 ・ ・ ・ (18)

Here, Ifsat0 is a target field current value at which a target magnetic saturation occurs in the rotor when the d-axis current Id is 0, and is set in advance. When the equation (18) is satisfied by increasing the field current detection value Ifr, even if the current command value Ido on the d-axis is returned to the basic current command value Idob on the d-axis, the rotor is subjected to the target magnetic saturation. It can be generated, and it can be judged that the responsiveness of the field current does not deteriorate.

Alternatively, the armature current control unit 33 enters the field when the absolute value of the field current deviation ΔIf becomes equal to or less than the release determination value Thcn after the maximum voltage is saturated and the condition for changing the d-axis current is satisfied. The change of the current command value Ido on the d-axis according to the current deviation ΔIf may be terminated.

When the field current detection value Ifr approaches the field current command value Ifo and the response delay of the field current is eliminated, the change processing of the d-axis current can be terminated.

As described above using the equation (1), the current command value calculation unit 331 determines the d-axis basic current command value Idob set according to the vector control method when the change condition of the d-axis current is not satisfied. , The final d-axis current command value Ido is set, and if the d-axis current change condition is satisfied, the change amount ΔIdo of the d-axis current command value is added to the d-axis basic current command value Idob. The value is set to the final d-axis current command value Ido.

<Control behavior>
FIG. 12 shows the control behavior under the same conditions as in FIG. 11 of the first embodiment. Similar to FIG. 11, the vertical axis of each graph represents the physical quantity in a dimensionless manner. The field voltage represents the maximum voltage that can be applied by 1.

At time t41, the field current command value Ifo increased stepwise from 0, and the field voltage command value Vfo was limited by the upper limit voltage value Vfmax to reach the maximum voltage saturation state, as in FIG. Therefore, the condition for changing the d-axis current is satisfied.

Since the change condition of the d-axis current is satisfied between the time t41 and the time t42, the change amount ΔIdo of the current command value of the d-axis is calculated according to the field current deviation ΔIf, and the basic current command value of the d-axis is calculated. The value obtained by adding the change amount ΔIdo of the current command value of the d-axis to the Ido is set as the current command value Ido of the d-axis. Therefore, as described with reference to FIG. 11, when the maximum voltage saturation state occurs, the response delay of the field current and the output torque Tr can be reduced.

Then, since the equation (18) was established at time t42, the armature current control unit 33 determined that the change condition of the d-axis current was no longer satisfied, and ended the process of changing the current command value of the d-axis. The basic current command value Ido on the d-axis is set to the current command value Ido on the d-axis. When the equation (18) is satisfied, the response delay of the field current and the output torque Tr does not deteriorate even if the current command value Ido of the d-axis is returned to the basic current command value Ido of the d-axis.

3. 3. Embodiment 3
Next, the rotary machine 1 and the control device 11 according to the third embodiment will be described. The description of the same components as those in the first embodiment will be omitted. The basic configuration of the rotary machine 1 and the control device 11 according to the present embodiment is the same as that of the first embodiment. In the first embodiment, the mutual inductance between the armature winding and the field winding is very small, but in the present embodiment, the mutual inductance between the armature winding and the field winding is small. Is too big to ignore.

Therefore, the voltage equation of the field winding can be expressed by the following equation. Compared with the equation (8) of the first embodiment, the term of mutual inductance Mf is added to the second term on the left side.

<Control behavior when the field current command value Ifo increases>
FIG. 13 shows the control behavior of a comparative example in which the basic current command value Idob on the d-axis is set to the current command value Ido on the d-axis as it is for the rotating machine 1 in which the mutual inductance Mf cannot be ignored. The vertical axis of each graph shows the physical quantity dimensionless. The field voltage represents the maximum voltage that can be applied by 1.

At time t51, the torque command value To increases stepwise from 0, the field current command value Ifo increases stepwise from 0, and the current command value Iqo on the q-axis increases stepwise from 0. The current command value Ido on the d-axis is gradually decreased from 0. Since the amount of increase in the torque command value To is large, the amount of increase in the field current command value Ifo is large.

The field voltage command value Vfo is limited by the upper limit voltage value Vfmax and is in the maximum voltage saturation state (from time t51 to time t52). Therefore, the responsiveness of the field current feedback control system is deteriorated.

Immediately after time t51, the current detection value Idr on the d-axis decreases sharply, so that the second term on the left side of equation (19) increases in the positive direction, and the entire right side of equation (19) is boosted. , The field current detection value Ifr is increased, and the responsiveness is improved.

However, after that, since the maximum voltage is saturated, the response delay of the field current detection value Ifr becomes large, and the response delay of the rotor magnetic flux ψ and the output torque Tr that change according to the field current detection value Ifr. Is getting bigger.

Next, FIG. 14 shows the control behavior according to the present embodiment in which the change processing of the current command value of the d-axis according to the field current deviation ΔIf is performed under the same conditions as in FIG.

Similar to FIG. 13, the field voltage command value Vfo is limited by the upper limit voltage value Vfmax and is in the maximum voltage saturation state (from time t61 to time t62). Since the field current deviation ΔIf is large after the time t61, the amount of change ΔIdo of the current command value on the d-axis is large, and the current command value Ido on the d-axis is greatly increased.

Immediately after time t61, the current detection value Idr on the d-axis increases sharply, so that the second term on the left side of equation (19) increases in the negative direction, and the entire right side of equation (19) is stepped down. , The field current detection value Ifr is lowered and becomes a negative value.

Immediately after time t61, the decrease in the rotor magnetic flux due to the decrease in the field current detection value Ifr exceeded the increase in the rotor magnetic flux due to the increase in the current detection value Idr on the d-axis, so that the rotor magnetic flux temporarily decreased. , The output torque Tr is temporarily reduced.

The rotor magnetic flux ψ is expressed by the equations (10) and (11), and is determined by the balance between the d-axis current Id and the field current If, but can be negative. Therefore, the rotor may be provided with a permanent magnet having the same magnetic flux direction as the electromagnet. By providing a permanent magnet, it is possible to suppress the rotor magnetic flux ψ from becoming negative.

Therefore, as compared with FIG. 13, while the current detection value Idr of the d-axis is increasing, the increase of the field current detection value Ifr is delayed, and the increase of the output torque Tr is delayed. On the other hand, due to the increase in the d-axis current, the rotor is in a magnetically saturated state, and the field current detection value Ifr is increased with good responsiveness. Then, as the field current detection value Ifr increases, the change amount ΔIdo of the d-axis current command value calculated by the equation (15) gradually decreases, and when the d-axis current detection value Idr gradually decreases, the equation (19) The second term on the left side of) becomes positive, and acts in the direction of increasing the field current detection value Ifr. Therefore, as compared with FIG. 13, the field current detection value Ifr increases faster, and the output torque Tr increases faster.

Therefore, in the rotating machine 1 having a large mutual inductance Mf, immediately after the field current command value Ifo increases and the field current deviation ΔIf increases, the increase of the field current If and the output torque Tr is delayed, but after that, the field The increase of the magnetic current If and the output torque Tr becomes faster. Therefore, as in the case of the rotary machine 1 having a small mutual inductance Mf, the responsiveness of the field current If and the output torque Tr can be improved by changing the d-axis current.

Further, in order to reduce the fluctuation of the output torque Tr due to the mutual inductance Mf, the response delay processing (for example, the primary delay processing) is performed on the change amount ΔIdo of the current command value of the d-axis, and the left side of the equation (19). Even if the absolute value of the second term is reduced or the current command value Iqo of the q-axis is changed according to the change amount ΔIdo of the current command value of the d-axis as described using the equation (17). good.

<Control behavior when the field current command value Ifo decreases>
FIG. 15 shows the control behavior of a comparative example in which the basic current command value Idob on the d-axis is set to the current command value Ido on the d-axis as it is for the rotating machine 1 in which the mutual inductance Mf cannot be ignored. The vertical axis of each graph shows the physical quantity dimensionless. The field voltage represents the minimum voltage that can be applied by -1.

At time t71, the torque command value To decreases stepwise, the field current command value Ifo decreases stepwise, the q-axis current command value Iqo decreases stepwise, and the d-axis current command value. Ido is increasing step by step.

Immediately after time t71, the current detection value Idr on the d-axis increases sharply, so that the second term on the left side of equation (19) increases in the negative direction, and the entire right side of equation (19) is stepped down. , The field current detection value Ifr is lowered, and the responsiveness is improved. However, after that, the response delay of the field current If becomes large, and the response delay of the output torque Tr occurs. Then, at time t72, the field current detection value Ifr reaches the field current command value Ifo, and the output torque Tr reaches the torque command value To.

Next, FIG. 16 shows the control behavior according to the present embodiment in which the change processing of the current command value of the d-axis according to the field current deviation ΔIf is performed under the same conditions as in FIG.

At time t81, the field current command value Ifo decreases stepwise, and the field current deviation ΔIf increases in the negative direction. The current command value Ido is greatly reduced.

Immediately after time t81, the current detection value Idr on the d-axis decreases sharply, so that the second term on the left side of equation (19) increases in the negative direction, and the entire right side of equation (19) is stepped down. , The field current detection value Ifr is increasing. Therefore, the field current deviation ΔIf increases in the negative direction, the field voltage command value Vfo is limited to the lower limit by the lower limit voltage value Vfmin, and the minimum voltage is saturated.

Immediately after time t81, the rotor magnetic flux decreased due to the decrease in the current detection value Idr on the d-axis, but the decrease in the rotor magnetic flux was temporarily insufficient because the rotor magnetic flux increased due to the increase in the field current detection value Ifr. Therefore, the rate of decrease of the output torque Tr is temporarily slowed down.

After that, as the absolute value of the field current deviation ΔIf gradually decreases, the amount of change ΔIdo of the current command value on the d-axis gradually increases. When the current detection value Idr on the d-axis gradually increases, the second term on the left side of the equation (19) becomes negative and acts in the direction of decreasing the field current detection value Ifr. At time t82, the field current detection value Ifr reaches the field current command value Ifo, and the output torque Tr reaches the torque command value To. Therefore, compared to the time t72 in FIG. 15, the final field current detection value Ifr decreases faster, and the output torque Tr decreases faster.

Therefore, in the rotating machine 1 having a large mutual inductance Mf, immediately after the field current command value Ifo decreases and the field current deviation ΔIf increases in the negative direction, the decrease of the field current If and the output torque Tr is delayed. After that, the field current If and the output torque Tr decrease rapidly. Therefore, as in the case of the rotary machine 1 having a small mutual inductance Mf, the responsiveness of the field current If and the output torque Tr can be improved by changing the d-axis current.

Further, in order to reduce the fluctuation of the output torque Tr due to the mutual inductance Mf, the response delay processing (for example, the primary delay processing) is performed on the change amount ΔIdo of the current command value of the d-axis, and the left side of the equation (19). Even if the absolute value of the second term is reduced or the current command value Iqo of the q-axis is changed according to the change amount ΔIdo of the current command value of the d-axis as described using the equation (17). good.

<Example of diversion>
In each of the above embodiments, the case where the rotary machine 1 is a generator motor for a vehicle has been described as an example. However, the rotary machine 1 may be an electric motor, a generator, or may be used for various devices other than a vehicle.

In each of the above embodiments, a case where a set of three-phase armature windings is provided on the stator has been described as an example. However, a plurality of sets (for example, two sets) of armature windings may be provided on the stator, and armature current control units of an inverter and a control device may be provided corresponding to each set of armature windings.

Although the present application describes various exemplary embodiments and examples, the various features, embodiments, and functions described in one or more embodiments are applications of a particular embodiment. It is not limited to, but can be applied to embodiments alone or in various combinations. Therefore, innumerable variations not illustrated are envisioned within the scope of the techniques disclosed herein. For example, it is assumed that at least one component is modified, added or omitted, and further, at least one component is extracted and combined with the components of other embodiments.

1 Rotating machine, 4 field winding, 5 inverter, 9 converter, 11 rotating machine control device, 12 armature winding, 14 rotor, 18 stator, 32 armature current detector, 33 armature current control unit, Ido d-axis current command value, Ido d-axis basic current command value, ΔIdo d-axis current command value change amount, Idr d-axis current detection value, Iqo q-axis current command value, Iqob q-axis basic current command Value, change amount of current command value of ΔIqo q-axis, current detection value of Iqr q-axis, Ifo field current command value, Ifr field current detection value, ΔIf field current deviation, target saturation field of Ifsat0 Id = 0 Magnetic current value, Ksr conversion constant, Mf mutual inductance, Thcn release judgment value, To torque command value, Tr output torque, Vdc DC voltage, Vdo d-axis voltage command value, Vqo q-axis voltage command value, Vfmax field voltage Upper limit voltage value of command value, lower limit voltage value of Vfmin field voltage command value, Vfo field voltage command value, dLIf current differential inductance

Claims (10)

A control device for a rotating machine that controls a rotating machine having a rotor provided with field windings and a stator provided with armature windings.
The armature current command value, which is the current command value of the armature winding, is calculated, the armature voltage command value is calculated based on the armature current command value, and the inverter is based on the armature voltage command value. An armature current control unit that applies a voltage to the armature winding by controlling the switching element to be turned on and off.
A field current detector that detects the field current flowing through the field winding,
The field current command value, which is the current command value of the field winding, is calculated, the field voltage command value is calculated based on the field current command value, and the converter is based on the field voltage command value. A field current control unit that applies a voltage to the field winding by controlling the switching element to be turned on and off is provided.
The direction of the magnetic poles of the rotor is defined as the d-axis, and the direction 90 ° ahead of the d-axis in terms of electrical angle is defined as the q-axis.
The armature current control unit changes the d-axis component of the armature current command value according to the deviation between the field current command value and the field current detection value .
When the armature current control unit reaches the maximum voltage saturation state in which the field voltage command value becomes equal to or higher than the maximum voltage that can be applied to the field winding, the armature current control unit determines the armature current command value according to the deviation. A controller for a rotating machine that changes the d-axis component . In the armature current control unit, the detected value of the field current is Ifr, the conversion constant is Ksr, the d-axis component of the armature current command value before the change is Idob, and the d-axis component of the armature current is When it is 0, the target field current value at which the target magnetic saturation occurs in the rotor is set to Ifsat 0.
After reaching the maximum voltage saturation state,
Ifr + Idob x Ksr ≧ Ifsat0
The control device for a rotary machine according to claim 1 , wherein the change of the d-axis component of the armature current command value according to the deviation is terminated when the equation of the above is satisfied. When the absolute value of the deviation becomes equal to or less than the release determination value after the maximum voltage saturation state is reached, the armature current control unit has a d-axis component of the armature current command value according to the deviation. The control device for a rotating machine according to claim 1 , wherein the change of the rotary machine is terminated. The rotation according to claim 2, wherein the conversion constant is set to the ratio of the d-axis inductance according to the number of turns of the armature winding to the inductance of the field winding corresponding to the number of turns of the field winding. Machine control device. A control device for a rotating machine that controls a rotating machine having a rotor provided with field windings and a stator provided with armature windings.
The armature current command value, which is the current command value of the armature winding, is calculated, the armature voltage command value is calculated based on the armature current command value, and the inverter is based on the armature voltage command value. An armature current control unit that applies a voltage to the armature winding by controlling the switching element to be turned on and off.
A field current detector that detects the field current flowing through the field winding,
The field current command value, which is the current command value of the field winding, is calculated, the field voltage command value is calculated based on the field current command value, and the converter is based on the field voltage command value. A field current control unit that applies a voltage to the field winding by controlling the switching element to be turned on and off is provided.
The direction of the magnetic poles of the rotor is defined as the d-axis, and the direction 90 ° ahead of the d-axis in terms of electrical angle is defined as the q-axis.
The armature current control unit changes the d-axis component of the armature current command value according to the deviation between the field current command value and the field current detection value.
The field current command value is Ifo, the field current detection value Ifr is set, the conversion constant is Ksr, and the amount of change in the d-axis component of the armature current command value is ΔIdo.
ΔIdo = (Ifo-Ifr) / Ksr
The amount of change is calculated using the formula of, and the d-axis component of the armature current command value is changed according to the amount of change.
The conversion constant is a control device for a rotating machine in which the ratio of the d-axis inductance according to the number of turns of the armature winding to the inductance of the field winding corresponding to the number of turns of the field winding is set. The control device for a rotary machine according to claim 5 , wherein the armature current control unit sets the amount of change of the d-axis component of the armature current command value to 0 or more. A control device for a rotating machine that controls a rotating machine having a rotor provided with field windings and a stator provided with armature windings.
The armature current command value, which is the current command value of the armature winding, is calculated, the armature voltage command value is calculated based on the armature current command value, and the inverter is based on the armature voltage command value. An armature current control unit that applies a voltage to the armature winding by controlling the switching element to be turned on and off.
A field current detector that detects the field current flowing through the field winding,
The field current command value, which is the current command value of the field winding, is calculated, the field voltage command value is calculated based on the field current command value, and the converter is based on the field voltage command value. A field current control unit that applies a voltage to the field winding by controlling the switching element to be turned on and off is provided.
The direction of the magnetic poles of the rotor is defined as the d-axis, and the direction 90 ° ahead of the d-axis in terms of electrical angle is defined as the q-axis.
The armature current control unit changes the d-axis component of the armature current command value according to the deviation between the field current command value and the field current detection value.
The armature current control unit is a control device for a rotating machine that changes the q-axis component of the armature current command value according to the amount of change of the d-axis component of the armature current command value. One of claims 1 to 7, wherein the response frequency of the control system from the field current command value to the field current value is lower than the response frequency of the control system from the armature current command value to the armature current value. The rotating machine control device described in the section. The control device for a rotating machine according to any one of claims 1 to 8 , wherein the rotor is provided with a permanent magnet in addition to the field winding. The control device for a rotary machine according to any one of claims 1 to 9 , wherein the rotary machine is a generator motor for a vehicle.

Images