JP3148209B2 - Control device for cycloconverter - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for a vector-controlled non-circulating current type cyclone converter.

[Prior Art] FIG. 2 is a block diagram showing a conventional control device for a cycloconverter of this type. In the figure, 1 is a speed setting device, 2 is a speed controller, 3 is a magnetic flux commander, and 4 is a magnetic flux controller, and a d-axis and q-axis current command generation circuit (first signal) (A generation circuit) 52 is configured. 53
A and 53B are the second and third signal generation circuits (both two-phase / 3
Phase coordinate converter) is a vector rotator 7, a two-phase / 3-phase converter 9
It consists of. 11 is a gate controller for the armature current of the AC motor 36, 12 is a three-phase AC power supply, 13 is a three-phase non-circulating current type sine wave cycloconverter CC, 22 is a q-axis current controller (proportional integration amplifier), 23 is a d-axis current controller (proportional integral amplifier), 24 is a first-order lag calculator, 25, 27, 28 are multipliers, 29 is a divider, 31 is an integrator, 5, 26, 30, and 40 are fixed Gain. 33 is a sine wave and cosine wave generator, 34 is a vector rotator, and 35 is a three-phase / two-phase converter. Reference numeral 37 denotes a resolver connected to the AC motor 36, and its output is input to the speed detector 32.

Speed feedback value omega _r of the AC motor 36 speed detector 32 has detected is sent to the speed controller 2 and the magnetic flux command unit 3. Speed controller 2 sends the velocity target value omega q-axis component current setpoint corresponding to _r ^* i _q ^*. The output currents i _R , i _S , and i _T of each phase of the AC motor 36 are converted into two-phase AC currents iα and iβ by a fourth signal generation circuit 51, and then the secondary magnetic flux is used as a secondary magnetic flux coordinate system. to be converted into quadrature DC volume, q-axis component current feedback value i _q ^- d-axis component current feedback value i _d ^-, and the former and the q-axis component current setpoint i _q ^* deviation epsilon _q between the q-axis component current The current controller 22 supplies the q-axis current to the controller 22.
The axis voltage command value V _q ^* is sent.

Flux controller 4 includes an output [Phi ^* of the magnetic flux command unit 3, the d-axis component current feedback value i _d ^- the output of the first order lag calculator 24 for [Phi ^- deviation between is input d-axis component current setpoint i _d ^* outputs, this value and the d-axis component current feedback value i _d ^- deviation between epsilon _d is input to the d-axis component current controller 23. The d-axis current controller 23 outputs a d-axis voltage command value V _d ^* .

The integrator 31 integrates the angular frequency ω ₀ of the rotating magnetic field to calculate a secondary magnetic flux phase θ _0, which is input to a sine wave and cosine wave generator 33. It sends out direction signals sin θ ₀ and cos θ ₀ .

The q-axis voltage command value V _q ^* is compensated for the interference term and the induced voltage term to be v _q ^* , and the d-axis voltage command value V _d ^* is the compensation for the interference term and the induced voltage term. v _d ^*, and the both Te, secondary flux direction signals sin [theta _0, the cos [theta] ₀ as a parameter, two-phase AC voltage by a vector rotator 7 of the second signal generating circuit 53A V.alpha ^*, after being converted to v? ^* After the three-phase conversion, the three-phase AC voltage set values V _R ^* , V _S ^* , and V _T ^* are supplied to the gate controller 11.

I _S ^* , i _R ^* , i _T ^* required for switching between the positive group converter 41 and the negative group converter 42 of the cycloconverter 13 are q
The third signal generation circuit 53B to which the axis current setting value i _q ^* and the d axis current setting value _id ^* are input, and the gate switch 1
4 and the gate switch 14 sets the three-phase AC current set value i
_R ^*, i _S ^*, according to the positive or negative polarity of i _T ^*, distributes the gate pulse to the positive group converter 41 or a negative group converter 42.

[Problems to be solved by the invention]

As described above, three-phase alternating current setpoint gate pulse sent from the gate controller _{^{11 i R *, i S *}} , according to the positive or negative polarity of i _T ^*, the gate switching unit 14 by the positive group converter 41
Alternatively, it is input to the negative group converter 42, but in order to prevent an AC short circuit at the time of switching between the positive group converter 41 and the negative group converter 42, a dead time of several ms (the time when both the group converters 41 and 42 are OFF) ), Distortion occurs in the AC output waveform of the cycloconverter 13, and the q-axis and d
The shaft current controller may respond excessively and generate an erroneous command.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problem, and has as its object to provide a control device of a cycloconverter which can prevent a malfunction of a current controller during a switching period of a positive / negative group converter.

[Means for solving the problem]

In order to achieve the above object, the present invention performs the integral operation of the q-axis current controller and the d-axis current controller for performing a proportional integral increasing operation and sending a voltage command value by switching between a positive group converter and a negative group converter. During the period, the system is configured to be stopped.

[Action]

According to the present invention, since the integration operation of the current controller is stopped, the integration term of the current controller holds the value before the start of switching, and the deviation of the distortion of the AC output waveform is not accumulated.

〔Example〕

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

In FIG. 1, a q-axis current controller 22 and a d-axis current controller 23 are configured to receive the output of the gate switch 14 through a signal line 15, and the q-axis current controller receiving the output. The current controller 22 and the d-axis current controller 23 hold the value of the integral term during the dead time. Other configurations are the same as those in FIG.

From the positive group converter 41 to the negative group converter 42,
During the reverse switching period (during the dead time), no current flows in the phase performing the switching operation, so that the current waveform of the phase does not become a sine wave. During this time, in the present embodiment, the q-axis current controller 22 and the d-axis current controller 23 stop the integration operation of the integration term and hold the value, so that the deviation of the distortion is not accumulated. , The q-axis voltage command value V _q ^* and the d-axis voltage command value V _d ^* do not include the distortion.

Moreover, in the present embodiment, the above-described effect can be obtained only by providing the signal line 15 between the gate switch 14 and the q-axis current controller 22 and the d-axis current controller 23 in the conventional control device. There are advantages that can be.

〔The invention's effect〕

As described above, according to the present invention, the integral term of the current controller is stopped during the switching period of the converter, thereby preventing the output of the current controller from including the distortion of the AC output waveform. As a result, control accuracy can be improved as compared with the related art.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a block diagram showing a conventional control device for a cycloconverter. In the figure, 7, 34... Vector rotator, 9.
Phase converter, 11 gate controller, 13 cycle converter, 14 gate switcher, 22 q-axis current controller, 23
... d axis current controller, 31 ... sine wave and cosine wave generator, 35 ... 3 phase / 2 phase converter, 41 ... positive group converter, 42
...... Negative group converter. In the drawings, the same reference numerals indicate the same or corresponding parts.

Continuation of the front page (56) References JP-A-56-150998 (JP, A) JP-A-64-69289 (JP, A)

Claims (1)

(57) [Claims] A gate pulse applied to a positive group converter and a negative group converter of a vector-controlled non-circulating current type cyclone converter is supplied to either a positive group converter or a negative group converter according to the positive / negative polarity of a three-phase AC current set value. In a control device for a cycloconverter having a gate switch for switching between the current controller and the d-axis current controller for performing a proportional integration operation and transmitting a voltage command value, the integration operation is performed during the switching period. Is a control device for a cycloconverter, wherein the control device is stopped.