异步电动机矢量控制调速系统英语文献翻
译
The Design of the Vector Control System of Asynchronous
motor
Abstract: Among various modes of the asynchronous motor speed
control
has
the
advantages
of
fast
response ,stability ,transmission of high-performance and wide speed range ,For the need of the asynchronous motor speed control ,the design uses 89C196 as the controller , and introduces the designs of hardware and software in details .The design is completed effectively with good performance simple structure and good prospects of development.
Key words :Asynchronous motor ,89C196 ,Vector control 1. Introduction AC
asynchronous
motor
is
a
higher
order ,multi-variable ,non-linear ,and strong coupling object ,using the concept of parameters reconstruction and state reconstruction of modern control theory to achieve decoupling between the excitation component of AC motor current and torque component ,and the control process of AC motor is equivalent to the control process of DC motor .the dynamic performance of AC speed regulation system obtaining
notable improvement ,thus makes DC speed replacing AC speed possible finally . The current governor of the higher production process has been more use of Frequency Control devices with vector-control. 2. Vector Control
With the criterion of producing consistent rotating magneto motive force ,the stator AC current iA,iB,
iC by 3S/2S
conversion in the three-phase coordinate system ,can be
sequivalent to AC current id ,iqs .in two-phase static coordinate
system .through vector rotation transformation of the re-orientation of the rotor magnetic field ,Equivalent to a synchronous rotation coordination of the DC current
ied ,iq.When observers at core coordinates with the rotation
etogether ,AC machine becomes DC machine .Of these ,the AC induction motor rotor total flux
?r ,it has become the
equivalent of the DC motor motor flux ,windings
deequivalent to the excitation winding of DC motor ,
ied
equivalent to the excitation current ,windings false static windings ,
qeequivalent to
ieq equivalent to the armature current
proportional to torque .After the transformation above ,AC asynchronous motor has been equivalent to DC motor .As a
result of coordinate transformation of the current (on behalf of magnetic momentum)space vector ,thus ,this control system achieved through coordinate transformation called the vector control system ,referred to VC system .According to this idea ,could constitude the vector control system that can control
?rand
ieqdirectly , as show in Figure 1.In the figure a given
and feedback signal through the controller similar to the controller that DC speed control system has used ,producing given signal
ie*qsof the excitation current and given signal
ie*dsof the armature current ,after the anti-rotation transform
VR obtaining
?1ie*qs and
ie*ds ,obtains i*A ,i*B ,i* by 3S/2S Cconversion .Adding the three signals controlled by current and frequency signal ?1 obtained by controller to the inverter controlled by current and frequency conversion current that asynchronous motor needs for speed. 3. The Content and Thought of the Design
This system uses 80C196 as controller ,consists of detection unit of stator three-phase current unit of keyboard input ,LCD display modules , given unit of simulation speed detection unit of stator three-phase voltage ,feedback unit of speed and output of control signals .System block diagram show in Figure 2, the system applies 16 bits MCU 80C196 as control core ,with some