* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download sensorless drive for high-speed brushless dc motor
Buck converter wikipedia , lookup
Electric machine wikipedia , lookup
Three-phase electric power wikipedia , lookup
Mains electricity wikipedia , lookup
Opto-isolator wikipedia , lookup
Alternating current wikipedia , lookup
Distributed control system wikipedia , lookup
Control theory wikipedia , lookup
Rectiverter wikipedia , lookup
Distribution management system wikipedia , lookup
Control system wikipedia , lookup
Power inverter wikipedia , lookup
Voltage optimisation wikipedia , lookup
Electric motor wikipedia , lookup
Resilient control systems wikipedia , lookup
Power electronics wikipedia , lookup
Brushless DC electric motor wikipedia , lookup
Induction motor wikipedia , lookup
Brushed DC electric motor wikipedia , lookup
Stepper motor wikipedia , lookup
SENSORLESS DRIVE FOR HIGH-SPEED BRUSHLESS DC MOTOR BASED ON THE VIRTUAL NEUTRAL VOLTAGE ABSTRACT: The brushless dc (BLDC) motor can be driven by either pulse-width modulation (PWM) or pulse-amplitude modulation (PAM) techniques. Unfortunately, neither of them can be the most suitable method for the high-speed BLDC motor in the wide speed range, so a hybrid drive method combining PWM and PAMis first introduced. Then, this paper proposes a new sensor less control method based on the virtual neutral voltage for high-speed BLDCmotor to suit for this hybrid drive method. In order to obtain the commutation signals from this seriously unclear voltage signal due to the commutation notches and electromagnetic interference, a low-pass filter with super low cutoff frequency is employed at the price of a large phase delay. Meanwhile, a novel sensor less control method based on the transition between “90–α” and “150–α” is introduced to handle the severe phase delay. At last, the feasibility and effectiveness of the proposed drive method and the sensor less control method are verified by several experiment results. INTRODUCTION: In recent years, high-speed brushless dc (BLDC) motor, which due to its high efficiency, compactness, low cost, and maintenance compared with a brush dc motor, is receiving more and more interest in industrial automation, especially on blowers and compressors. Since the rotation speed of a high-speed motor can reach up to tens of thousands revolutions per minute(r/min) due to the development of bearing technology, a proper drive method to ensure low loss and high efficiency in a wide speed range becomes a critical issue. Meanwhile, it is well known that the BLDC motor requires six discrete rotor positions for the inverter operation. These are typically generated by Hall sensors mounted on a motor. However, it is a well-known fact that these sensors increase the cost of the motor and need special mechanical arrangements to be mounted. To break through the aforementioned restriction, many position sensorless methods have been considered as potential solutions, thus prompting the sensorless operation of the BLDC motor to be a hot issue in recent years. Therefore, to cope with these two issues effectively will promote the development of the high-speed BLDC motor EXISTING SYSTEM: Generally, the BLDC motor can be driven by either pulse-width modulation (PWM) or pulse-amplitude modulation (PAM) techniques. It is well known that the inverter, which applied to most of the BLDC motor drive systems, is controlled by the PWM scheme for varying the voltage. When the PWM control is valid, the dc-link voltage is fixed, and the duty of the inverter is controlled by the speed and load conditions. Also, it is popular in the low-speed BLDC motor control. Unfortunately, for a high speed BLDC motor, the high-frequency and large-range current ripple will inevitably increase the copper and rotor iron losses. The PAM scheme is another popular control mode for the BLDC motor, especially at high speed. For PAM control, 120-degree commutation control, i.e., the so called six-step mode is generally used with lower switching frequency than the PWM control. Meanwhile, the dc-link voltage can be adjusted according to the error between the speed and its reference. Moreover, the conclusion that the PAM control for the BLDC motor can provide lower harmonic content and higher efficiency than the PWM control shows the superiority of PAM control at high speed PROPOSED SYSTEM: Generally, the BLDC motor can be driven by either pulse-width modulation (PWM) or pulse-amplitude modulation (PAM) techniques. It is well known that the inverter, which applied to most of the BLDC motor drive systems, is controlled by the PWM scheme for varying the voltage. When the PWM control is valid, the dc-link voltage is fixed, and the duty of the inverter is controlled by the speed and load conditions. Also, it is popular in the low-speed BLDC motor control. Unfortunately, for a high speed BLDC motor, the high-frequency and large-range current ripple will inevitably increase the copper and rotor iron losses. The PAM scheme is another popular control mode for the BLDC motor, especially at high speed. For PAM control, 120-degree commutation control, i.e., the so called sixstep mode is generally used with lower switching frequency than the PWM control. Meanwhile, the dc-link voltage can be adjusted according to the error between the speed and its reference. Moreover, the conclusion that the PAM control for the BLDC motor can provide lower harmonic content and higher efficiency than the PWM control shows the superiority of PAM control at high speed ADVANTAGES: Simplicity of implementation, robust to electronic noise, and eliminating the need for the motor neutral wire BLOCK DIAGRAM: TOOLS AND SOFTWARE USED: MPLAB – microcontroller programming. ORCAD – circuit layout. MATLAB/Simulink – Simulation APPLICATIONS: Motor drives