CN201846300U

CN201846300U - Closed loop vector control frequency converter

Info

Publication number: CN201846300U
Application number: CN201020611447XU
Authority: CN
Inventors: 何畏
Original assignee: SHENZHEN ZHENGXUAN ELECTRIC CO Ltd
Current assignee: Shenzhen Sine Electric Co., Ltd.
Priority date: 2010-11-17
Filing date: 2010-11-17
Publication date: 2011-05-25
Anticipated expiration: 2020-11-17

Abstract

The utility model relates to the technical field of frequency conversion, in particular to a closed loop vector control frequency converter of a three-phase asynchronous motor. A cross shaft current direction of stator current of the asynchronous motor is coincident to a vector direction of stator voltage, straight shaft current of the stator current is lagged behind the vector direction of the stator voltage by 90 degrees, vector voltage drop of the stator current on stator resistor is adjusted, and accordingly the closed loop vector control frequency converter has a high-torque vector control performance. The closed loop vector control frequency converter can be widely applied to industries of spinning, numerical control machines and the like.

Description

A kind of closed-loop vector control of conversion device

[technical field]

The utility model relates to the converter technique field, specifically refers to a kind of closed-loop vector control of conversion device of threephase asynchronous machine.

[background technology]

In existing asynchronous machine pulse width modulation frequency changing transformer, the relation curve of its electric moter voltage and stator angular frequency is often represented with a broken line, and do not count the material impact that variation brought of stator current vector pressure drop size and direction on stator resistance in real time, its result causes stator magnetic linkage to fluctuate up and down and can not remain on the desired value, stator field is underexcitation or cross and to encourage the magnetic saturation electric current that causes and all can cause motor torque to descend, and this problem is particularly serious startup stage that motor is in or during low-speed stage.The variable-frequency transformer that has, even current overload to 150%, but it is 100% still very difficult that detent torque will reach, it is worthless adopting the way that strengthens the inverter current capacity to improve torque, because it is low with operational efficiency so to cause product cost to rise significantly, its result causes the waste of resource and energy.

[utility model content]

When the purpose of this utility model is to solve existing frequency converter and is used for the asynchronous machine variable-frequency variable-voltage, electric moter voltage is except outside the Pass having with the stator angular frequency, also adjust, thereby have high torque (HT) vector control performance with stator current vector pressure drop size on stator resistance.

A kind of closed-loop vector control of conversion device, comprise that asynchronous machine contains three coordinate converter, the current sensors that mutually change converter, output transverse axis electric current and the direct-axis current of two-phases, has the variable-frequency transformer of the pulse-width modulation of voltage sensor concurrently, the transverse axis sense of current of the stator current of its asynchronous machine overlaps with the direction vector of stator voltage, and direction vector 90 degree of the direct-axis current hysteresis stator voltage of stator current.

The closed-loop vector control of conversion device of the utility model threephase asynchronous machine, the transverse axis sense of current of the stator current of its asynchronous machine overlaps with the direction vector of stator voltage, and direction vector 90 degree of the direct-axis current hysteresis stator voltage of stator current, stator current vector pressure drop size on stator resistance is adjusted, thereby had high torque (HT) vector control performance.Can be applied to industries such as weaving, Digit Control Machine Tool widely.

[description of drawings]

Fig. 1 is the utility model frequency converter and motor winding diagram;

Fig. 2 is the utility model custom system plate figure;

Fig. 3 is a frequency-conversion voltage-varying speed system diagram;

Fig. 4 is another frequency-conversion voltage-varying speed system diagram.

[embodiment]

Below in conjunction with accompanying drawing, the utility model is done detailed explanation:

In Fig. 1,100 for containing three mutual commentaries on classics two phasing commutators, coordinate converter, current sensors, having the variable-frequency transformer of voltage sensor in interior pulse-width modulation concurrently, its three-phase output is connected to asynchronous machine 200, and speed probe 300 also is installed on motor shaft as required.Angular frequency that variable-frequency transformer 100 generations are certain and voltage input signal are to realize its function.As shown in Figure 2, custom system plate 400 is equipped with one of Intel8032 single-chip microcomputer, one of memory EPROM2764, one of parallel interface, one of one of D/A converter DAC0832 and A/D converter, in order to improve operational precision, the A/D converter MAX197 that is positive and negative 5V with a voltage removes to replace ADC0809; In addition in order to increase the simulation delivery outlet, also set up two D/A converter ADC0832, A/D converter MAX197 uses 5 passages, the stator angular frequency, magnetic linkage, phase resistance, direct-axis current ID and the transverse axis electric current I Q that are respectively the motor generation provide the sampling input, and potentiometer ST1 and ST2 are respectively for the usefulness of presetting magnetic linkage and phase resistance among the figure.Three D/A converter DAC0832 then are respectively applied for the usefulness of the simulation output of voltage V1, motor torque ME and slip angular frequency W2.

Among Fig. 3, the direct-axis current ID and the transverse axis electric current I Q of variable-frequency transformer 100 outputs are sent to custom system plate 400, and the voltage V1 of custom system plate 400 outputs is sent to variable-frequency transformer 100.Rotating speed angular frequency instruction WMO value and after adder-subtracter 10 places addition, generate stator angular frequency W1 and be sent to frequency converter 100 and custom system plate 400 from the slip angular frequency W2 of custom system plate 400.In Fig. 4, the output W20 value of torque controller 20 and rotating speed angular frequency WM value generate stator angular frequency W1 and are sent to variable-frequency transformer 100 and custom system plate 400 after adder-subtracter 11 places addition; Torque instruction MEO value obtains the input value of torque controller after adder-subtracter 12 places deduct motor torque ME value; When switch S S was closed, torque instruction value was from the output of speed regulator 21; When switch S S opened, torque instruction value was from the direct control of outer input; Rotating speed angular frequency instruction WMO value obtains the input value of speed regulator 21 after adder-subtracter 13 places deduct rotating speed angular frequency WM value, so constitute the frequency-conversion voltage-varying speed system.

The utility model can make motor 200 voltages adjust with stator current variation of vector pressure drop size and direction on stator resistance automatically, so that stator magnetic linkage keeps desired value, thereby have high torque (HT) vector control performance, a kind of frequency-conversion voltage-varying speed system that contains the high-performance torque vector control of torque or current closed-loop also is provided.

The above only is a better embodiment of the present utility model; protection range of the present utility model does not exceed with above-mentioned execution mode; as long as the equivalence that those of ordinary skills do according to the utility model institute disclosure is modified or changed, all should include in the protection range of putting down in writing in claims.

Claims

1. closed-loop vector control of conversion device, comprise that asynchronous machine contains three coordinate converter, the current sensors that mutually change converter, output transverse axis electric current and the direct-axis current of two-phases, has the variable-frequency transformer of the pulse-width modulation of voltage sensor concurrently, it is characterized in that: the transverse axis sense of current of the stator current of asynchronous machine overlaps with the direction vector of stator voltage, and direction vector 90 degree of the direct-axis current hysteresis stator voltage of stator current.