The properties and the design of PWM systems are discussed. The relations among the orifice areas of the valves, initial times and the rate of piston areas are deduced. Also a PWM system is designed and some experimen...The properties and the design of PWM systems are discussed. The relations among the orifice areas of the valves, initial times and the rate of piston areas are deduced. Also a PWM system is designed and some experiments are done. The experiment results agree with those of theory analyses. It can be shown that the relations are correct and the conclusion of theory analyses is reasonable.展开更多
The improved current-doubler-rectifier zero-voltage-switching PWM full-bridge converter (CDR ZVS PWM FB converter) achieves ZVS for the switches in a wide load range with the use of the energy stored in the output fil...The improved current-doubler-rectifier zero-voltage-switching PWM full-bridge converter (CDR ZVS PWM FB converter) achieves ZVS for the switches in a wide load range with the use of the energy stored in the output filter inductances, and the rectifier diodes commute naturally, therefore no oscillation and voltage spike occurs. The transformer needs no special manufacture method to limit the leakage inductance. The ZVS achievement and the design considerations for the output filter inductances and the blocking capacitor are discussed for the improved CDR ZVS PWM FB converter. A 540 W prototype converter is built in the lab to verify the operational principle and design considerations for the improved converter, the experimental results are also included.展开更多
The property of silicon micro-capacitive accelerometer is analyzed and discussed by establishing the model of the sensor,to lay a basis for optimization design of sensor system structure. Discussed issues include the ...The property of silicon micro-capacitive accelerometer is analyzed and discussed by establishing the model of the sensor,to lay a basis for optimization design of sensor system structure. Discussed issues include the static modeling and dynamic behavior of the two commonly used structures,i.e., double-cantilever supported and four-beam supported structures, and also the measurement range of these devices.展开更多
This paper focuses on the use of the touchpad (key), STC89C51RC monolithic integrated circuit PWM control signal, which changed the traditional mechanical buttons as a DC motor rotational speed and steering control ...This paper focuses on the use of the touchpad (key), STC89C51RC monolithic integrated circuit PWM control signal, which changed the traditional mechanical buttons as a DC motor rotational speed and steering control method. Touch switch advantages compared with the traditional mechanical switches are: first, the quieter second, more sensitive; third, faster; four, long life and so on. Specialized chips are also used in the article the PWM signal system, and the principle of PWM signal, method and how the software adjust the duty cycle of the PWM signal to control its input signal waveforms are are described in detail. In addition, this article also introduced consisting of triode amplifier circuit of h-bridge amplifier as a DC motor driving module, enabling the control of DC motor speed. On the software side, PI was described in detail in the article arithmetic program initializes write ideas and specific programs such as program implementation.展开更多
文摘The properties and the design of PWM systems are discussed. The relations among the orifice areas of the valves, initial times and the rate of piston areas are deduced. Also a PWM system is designed and some experiments are done. The experiment results agree with those of theory analyses. It can be shown that the relations are correct and the conclusion of theory analyses is reasonable.
文摘The improved current-doubler-rectifier zero-voltage-switching PWM full-bridge converter (CDR ZVS PWM FB converter) achieves ZVS for the switches in a wide load range with the use of the energy stored in the output filter inductances, and the rectifier diodes commute naturally, therefore no oscillation and voltage spike occurs. The transformer needs no special manufacture method to limit the leakage inductance. The ZVS achievement and the design considerations for the output filter inductances and the blocking capacitor are discussed for the improved CDR ZVS PWM FB converter. A 540 W prototype converter is built in the lab to verify the operational principle and design considerations for the improved converter, the experimental results are also included.
文摘The property of silicon micro-capacitive accelerometer is analyzed and discussed by establishing the model of the sensor,to lay a basis for optimization design of sensor system structure. Discussed issues include the static modeling and dynamic behavior of the two commonly used structures,i.e., double-cantilever supported and four-beam supported structures, and also the measurement range of these devices.
文摘This paper focuses on the use of the touchpad (key), STC89C51RC monolithic integrated circuit PWM control signal, which changed the traditional mechanical buttons as a DC motor rotational speed and steering control method. Touch switch advantages compared with the traditional mechanical switches are: first, the quieter second, more sensitive; third, faster; four, long life and so on. Specialized chips are also used in the article the PWM signal system, and the principle of PWM signal, method and how the software adjust the duty cycle of the PWM signal to control its input signal waveforms are are described in detail. In addition, this article also introduced consisting of triode amplifier circuit of h-bridge amplifier as a DC motor driving module, enabling the control of DC motor speed. On the software side, PI was described in detail in the article arithmetic program initializes write ideas and specific programs such as program implementation.