Research And Realization Of SVPWM Varied Frequency Speed Regulating Technology

Vector Control as an advanced control strategy in the electrical unified theory, electrical and mechanical energy conversion and coordinate transformation of the theory developed on the basis of, with an advanced nature, innovative and practical features. Vector Control is the idea of the model through asynchronous motor coordinate transformation, to make it a DC motor model, stator current vector for the decomposition of the rotor magnetic field orientation of the two DC component and are under control, thus realizing the flux and torque Decoupling control to meet the DC motor control results. Space Vector Pulse Width Modulation as a new type of vector control technology, a high-voltage utilization, output harmonic less, the advantages of control method is simple, at home and abroad in recent years become a hot research.This paper analyzed the characteristics of VVVF technology, domestic and international status quo and development trend, a detailed analysis of SVPWM The principle of SVPWM conducted an in-depth technical analysis and research, and realized the SVPWM simulation with MATLAB6.0, in this developed on the basis of a programme of the overall design of this subject, and from the controller hardware design and software design are two aspects of the concrete realization.The system'main circuit is AC-DC-AC of voltage reference, and power MOSFET make a three-phase inverter bridge; Driven use the IR2103 with internal bootstrap circuit which produced by the IR company of U.S. IR2103 only need 10 ~ 20 V power will be able to achieve drive, simplify circuit design; Design of the DC bus voltage detection circuit, the current detection circuit, fault detection and protection circuits, communications circuits, and other external circuit; Control circuit used ARM7 series of LM3S615 as the core of control, the controller whose price is similar with of 8 and 16-bit microcontroller, it able to provide 32-bit processor performance, LM3S615 the work of the highest frequency can reach 50MHz, compatible with the Thumb Thumb-2 specific instruction set processor core, and with six road independent PWM port, it has two AD accuracy of sampling channels, 32K single-cycle FLASH and 8K single-cycle SRAM, its rich resources to meet all of the internal control requirements .The system software used C language, design of the system main program and PWM interrupt handling procedures, system initialization, frequency control, current and voltage sampling, display and failures in dealing with the main program are completed, trigonometric calculation, SVPWM subroutine, the scan button in the PWM Interruption in the process completed. In this paper, SVPWM routines to simplify the design of the algorithm, a PWM synchronous control improved control accuracy, and compared to the traditional control strategy greatly shortened the reference voltage vector of the sampling period, so that the internal motor flux more approximation round, to reduce fluctuation. At the same time, the system LCD display, and key driver of the embedded, to facilitate the practical application of specific control system Settings parameters.Finally, a system of hardware and software debugging and comprehensive debug unit, on the basis of the development of an experimental prototype to test, test results show that the driver stable performance, reliable operation, small AC motor speed to meet the needs-driven, SVPWM control the electrical and high-efficiency, high output voltage utilization, in line with the theoretical analysis of the results.