发布时间 : 星期四 文章单相变频电源设计 - 原版 - 图文更新完毕开始阅读7cb0da6510661ed9ad51f3f7
外文资料原文
Due to the multiple overlay approach, the harmonic content of the inverter output voltage is very small, conventional supply voltage has reached the permissible harmonic content, does not cause additional harmonic motor heating. The output voltage dV/dt is small, does not significantly increase the stress to the motor, it can supply to the general standard AC motors, and does not require derating, especially for old equipment . Since the output voltage harmonics and dV/dt is very small, no additional output filter output cable can be very long. Since the harmonic small additional torque ripple is small, thus avoiding the mechanical resonance caused by transmission and bearing wear are greatly reduced.
In the input side , due to the displacement of the drive even multiple secondary windings , such as total output 6KV +250 , +150 , +50 , -50 , -150 , -250 total of six kinds of winding , the primary current drive the corresponding current components are mutually uniform displacement , constitute the equivalent 36 pulse rectifier circuit , inverter results in greatly reduced input current harmonic content , well below the limits specified in the standard , even in the smaller capacity power grid when they can meet harmonic requirements . Inverter power factor up to 0.95 hours of work to meet the requirements of the power supply system. Will not run on the same power line interference occurs when electrical equipment so no additional power supply filters or power factor compensation device , it will not resonate drive to work with an existing compensation capacitor device, which was hailed as \no high-voltage inverter harmonics . \
The basic principle of the control unit:
Two optical fibers are used to connect and control between the control unit and each power unit. It can receive operation from the operation panel, I / O interface or communication channel commands and given signal, post-processing the output voltage, frequency reference signal to the three-phase control unit, where it is converted into a PWM control signal, the electrical/optical conversion convert an optical signal sent from the optical transmitter to the power unit port . Response information via the optical/electrical converter from the power unit into an electrical signal to the main controller centralized evacuation process. According to the host controller control commands, and operating information given signal, the response operation control
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电子科技大学成都学院本科毕业设计论文
information , state analysis , fault diagnosis , such as computing , fault after fault according to the nature of the fault processing, such as blocking system, high pressure trip, etc., and gives corresponding fault signal, the audio signal is also provided a fault. From the I/O interface can output running state (switch) and operating parameters (analog), the user may need to select output. Debugging interfaces with a PC via the PC running the debugger, you can debug and diagnostics in picture form , and at the same time waveform display and digital systems in five variables, the system debugging and diagnostics on the CPU unit good tools. The CPU unit is also equipped with a communication interface (RS232), communication can take control commands and reference signals to control the operation of the drive from the PC , and returns information about the operating status and operating parameters for centralized monitoring.
Master controller function block diagram shown above , the structure of the main controller for modular units , which is double the DSP CPU core unit via the bus interface board and phased A, B, C plate exchange information . From the interface submodule DI, AI acceptable command, a given signal, the motor current and voltage. CPU board according to the operation command given signal and other input signals, calculates the control information and status information. Phased A, B, C receive the control information from the CPU board plate, to generate a PWM control signal, the electric / optical converter , transmits the optical signal to the power control unit . The response signal from the power unit into an electrical signal in the phase control A, B, C plate , the evacuation process to CPU board handling . Status information can be sent via the interface board and interface sub- templates.
Operation panel, also as people -machine interface , a color touch-screen mode and digital mode two optional configurations. Operator panel control unit mounted on the cabinet front door, but there are lights on the doors and buttons. Operator panel with master controller via the communication interface with the CPU board is connected, you can enter commands for a given signal, the display operating status and operating parameters. You can display fault information, including by failure time has carried all before eight faults and failures are not sorted in the order of failure. CPU board has to communicate with the host computer communication interface, a standard RS232
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