JPS6149678A - Current command generator for synchronous motor - Google Patents

Abstract

PURPOSE:To improve the controlling accuracy and the responsiveness of a synchronous motor by obtaining a current command on the basis of a torque command, a power factor command and a magnetic flux command. CONSTITUTION:A magnetic flux command PHI is decided in a magnetic flux command generator 32 by using a power factor command i1q and a torque command T. Torque 7-component current command i1d is obtained by a divider 34 by the commands PHI and T, and a current amplitude command I0 is obtained in a current amplitude command generator 42 by the commands i1q and i1d. A current phase angle is obtained by a current leading angle calculator 40, a load angle command delta is obtained in a load angle command generator 44, added to the rotor phase angle theta0 in an adder 46 to obtain a phase angle command theta. A 3- phase AC current command generator 28 generates a current command i1 decided by the command I0 and theta, and supplies it to an inverter 12.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention is directed to a current command generator of a device for driving and controlling a till motor. It is something to do.

(Background of the invention) Patent No. 48-1823 Machima is known.

In a device that drives and controls a synchronous motor, a current command for the synchronous motor is generated as follows.

In FIG. 2, the DC output current of the DC power supply 10 is converted into a three-phase AC current by an inverter 12, and the AC current is supplied to a synchronous motor 14 as a drive current.

A rotation detection pulse is generated in the pulse generator 1G due to the rotation of the rotor of the synchronous motor 14, and the detection pulse is transmitted to the rotor phase angle detector 2 of the current command generator 18.
0.

Further, the torque command T of the torque command generator 22 is supplied to a constant@multiplier 24 and a constant multiplier 26 provided in the current command generator 18, and the output value of the constant multiplier 24 (current amplitude command >Io is supplied to a three-phase alternating current command generator 28, and the output value (load angle command δ) of the constant factor multiplier 26 is supplied to an adder 30.

The other input of this adder 30 is a rotor phase angle detector 2.
The rotor phase angle θ of the synchronous motor 14 found at 0. is supplied, and its interference value is supplied to a three-phase alternating current command generator 28 as a phase angle command θ.

In the three-phase AC current command generator 28, a three-phase AC current command 11 is generated based on the output 11iiiIo of the constant multiplier 24 and the output 1 of the adder 30, J5, and the current command 11 is It is supplied to the inverter 12.

The alternating current corresponding to the current command 11 obtained in this way is passed from the inverter 12 as a driving current to the synchronous motor 14.
is supplied to.

However, in the prior art, as understood from the above explanation, the current command 11 has a current amplitude (2) proportional to the torque command T. Since it is generated based on the load angle δ which is also proportional to the torque command, it is completely impossible to control the power factor of the synchronous motor 14. Therefore, the power factor of the generated torque i+lJ, This was inconvenient in improving its responsiveness.

(Object of the invention) The present invention has been made in view of the above-mentioned conventional problems,
The purpose of the present invention is to provide synchronization that allows torque control of a synchronous motor to be performed with high precision and good responsiveness (configuration of the invention).To achieve the above purpose, the present invention provides a power factor command generator that generates a power factor command. and a magnetic flux command calculating means for calculating a magnetic flux command based on a torque command and a power factor command; and a current command calculating means for calculating a current command based on a torque command, a power factor command, and a magnetic flux command. Features.

(Description of Embodiments) Hereinafter, preferred embodiments of the apparatus according to the present invention will be described based on the drawings.

In FIG. 1, a synchronous motor 14 is used as a driving source for a vehicle, and an on-vehicle battery is used as a DC power source 10.

In addition, the torque command generator 22 contains the accelerator pedal depression m.
The torque command T is supplied to a magnetic flux command generator 32 and a divider 34.

Further, this device is provided with a power factor command generator 36, which generates a power factor command of 1 or 1 depending on various state quantities (for example, the detected rotational speed of the synchronous motor 14). q
can be generated and supplied to the magnetic flux command generator 32, current advance color calculator 40, and current amplitude command generator 42 via the constant multiplier 38.

The magnetic flux command generator 32 is mainly composed of a microcomputer, and therefore the I1032A, CPU
32B and a memory circuit 32C.

And in the memory circuit 32C, Φ'2Lt+QΦ'+((Li+Q)2-φ2)Φ
2 + (LT) 2-0...The calculation formula for the magnetic flux command Φ that satisfies the equation (1) is stored on the table as a map characteristic, and from this the magnetic flux command is calculated using the torque command T and the power factor command 11q. Φ is required. In addition, the price is the same 1
The coil inductance of the 111 motor 14, the value φ, represents the rotor effective magnetic flux.

The magnetic flux command Φ obtained by this magnetic flux command generator 32
is supplied to the divider 34, which divides the torque command T by the magnetic flux Φ to obtain a torque component current command iId.

The torque component current command 11d is also supplied to the current lead color calculator 40, and in the current lead color calculator 40, the current phase angle θ1 is θ, -tan' (i, d/i +Q)-th ( 2)
It is determined by the formula.

Furthermore, the torque component current command 11d is supplied to the current amplitude command generator 42, and in this current amplitude command generator 42, the current amplitude command 1o is expressed as 1o=(i +Q2+i
1d'') - Required by the calculation of equation (3).

The torque component current commands i and d obtained by the divider 34 are also supplied to the load angle command generator 44, and "
In this load angle command generator 44, the load angle command δ is calculated by the calculation of δ=sin−+(17φ−T/φ)...Equation (4).

In this way, the current advance angle wave counter 40. The current phase angle θ1 and load angle command δ obtained by the load angle command generator 44 are supplied to an adder 46 together with the rotor phase angle θ0 of the rotor phase angle detector 20. These are added to obtain the phase angle command θ.

This phase angle command θ is supplied to the three-phase AC current command generator 28 together with the current amplitude command In obtained by the current amplitude command generator 42, and this three-phase AC current command generation H
In 28, current command ■+ (Iu, Iv, Iw
) is (u-), )ejθ...Equation (5) J
v □x l aOj(1?+2rt/υ...
Equation (6) 1'wr(Iej'θ+'I'''/J)
, , is determined by equation (7).

The present embodiment has the above configuration, and its operation will be explained below.

FIG. 3 shows a two-pole model of the synchronous motor 14, in which the q-axis is in the direction of the magnetic flux Φ observed from the outside, and the d-axis is in the direction orthogonal to this. .

Here, the effective magnetic flux of the rotor is φ, and this effective magnetic flux φ
When the angle formed by the q-axis is the load angle δ, the magnitude of the magnetic flux at each coordinate is Φ=φCOSδ+Li+Q... Equation (8) 0
=φsinδ+li, d =-・Equation (9) and torque T is expressed by ■=φ・11d...Equation (10).

In general, power factor means the phase difference between voltage and current (if the phase difference is α, it is expressed as COSα), and this
In the polar model, first, the voltage C can be found using the following equation.

e=dΦ/dt...Equation (11) At this time, if the absolute value of magnetic flux Φ is constant over time, vector Φ and vector C are orthogonal, and voltage vector e is Occurs only in the d-axis direction.

Here, in FIG. 3, a current 11q flows orthogonally to the voltage vector e, but the current 11q is a reactive current, and therefore can be considered as m which determines the power factor of the synchronous motor 14.

Therefore, in this embodiment, the command IIq for the current is used as the power factor command.

Then, using this power factor command t+Q and the torque command, the magnetic flux command generator 32 in FIG.
is determined.

In addition, in the above-mentioned quartic equation to obtain this magnetic flux command Φ, the value δ
has been deleted.

Also, since it takes a relatively long time to obtain the command Φ by solving the equation, in this embodiment, the commands T, ! The command Φ corresponding to +Q is stored as a map on the dimple, and the processing speed is improved by reading the map.

The torque component current command i is determined in the divider 34 by the magnetic flux command Φ obtained in this way and the l·ruq command T.
Id is obtained, and its command 11d is sent to the current advance angle wave counter 4.
0, which is supplied to the current amplitude command generator 42 and load angle command generator 44.

The current amplitude command generator 42 generates a current amplitude command ■ based on the power factor command 11q obtained by the constant multiplier 38 and the torque component current command 11d. is determined, and the command 1a is supplied to the three-phase AC current command generator 28.

In addition, the current advance angle wave counter 40 calculates the current phase angle, that is, the advance angle tan'(i, d/
+ +Q) is determined, a load angle command δ is determined in the load angle command generator 44, and these are added together with the rotor phase angle θ0 in the adder 46. The addition j is then picked up by the three-phase alternating current command generator 28 as a phase and phase angle command θ.

This three-phase AC current command generator 28 generates a current command 11 whose amplitude is determined by the command 1a and whose phase is determined by the command θ, and the current command II is supplied to the inverter 12.

In the inverter 12, the DC output current of the DC power supply 10 is converted into a three-phase AC drive current in accordance with the command 11, and the drive current is supplied to the synchronous motor 14.

As explained above, according to this embodiment, the current command is generated based on the power factor command and power factor control is performed together with torque control, so that the synchronous motor control k r! J, it becomes possible to improve responsiveness.

(Effects of the Invention) As explained above, according to the present invention, the current command is generated based on the power factor command and the power factor control is performed together with the torque control, so that the control Knffi of the synchronous motor and the responsiveness can be improved. It becomes possible to achieve this goal.

[Brief explanation of the drawing]

Fig. 1 is a block configuration diagram explaining a preferred embodiment of the device according to the present invention, Fig. 2 is a block Jf4 structure explaining the formation of the conventional device, and Fig. 3 is an explanation of a 2, 1 model of a synchronous motor. It is a diagram. 14...Synchronous motor 18...Current command generator 20...Rotor phase angle detector 22...Torque command generator 28...Three-phase alternating current command generator 34...Divider 3G...Power factor command generator 40...Current advance angle operator 42...Current amplitude command generator 44...Load angle command generator 46...Cylinder

Claims (1)

[Claims] (1) A power factor command generator that generates a power factor command, a magnetic flux command calculation means that calculates a magnetic flux command based on the torque command and the power factor command, and a current command that generates a current command based on the torque command, power factor command, and magnetic flux command. A current command generator for a synchronous motor, comprising: a current command calculating means for calculating a current command; and a current command generator for a synchronous motor.