Earticle

Neutral wire is one form of distribution lines for faults. Neutral wire will cause the neutral potential shift and increase the voltage, which may endanger electrical appliances and persons. The entire existing neutral wire automatic protection device are to protect the load side and there are not protective measures on the supply side. Has load protection side. The research of the protection system is that Bi-directional zero-phase method will be taken to obtain the voltage and current square wave after the emergence of neutral wire of the load side. Then each wave is sampled and the phase difference is calculated by microcomputer control system, which will be combined with the neutral current change detection to cut off the power of supply side and achieve the automatic protection. The system can well achieve automatic protection of neutral wire on the supply side.

The speech recognition is a kind of technology, which makes a machine change the speech signals into homologous text or order by recognition and comprehend. The speech recognition is a cross-subject, and it is becoming to the key-technology of human-computer interface in information technology. It makes man can operate the computer through the speech order without the keyboard. Speech recognition technology has be used in fields such household electronic products and intellectual toys. The bus controlled by speech signals proposed in this paper will be more powerful than traditional toy bus. It will be structure simple, strong stability, high precise. More important, its speech control system will has especial attraction to children. This paper Introduces hardware system and software system of speech control intellectual toy bus.

To install and debug electrical control equipment is a typical work position for students who major in automation in vocational college. In order to meet the needs of this position, the connection and designation of electrical control lines have become a required part for most of these students. This paper proposes a simple method of automation detection of electrical control circuit based on single chip microcomputer, which is convenient for students to learn by themselves and for teachers to reduce the work pressure in reaching practically. Considering automatic detection of electrical control circuit by single chip microcomputer, the method synthesizes the technology of single chip microcomputer and embedded technology, and codes to construct net lists with nodes through connecting electrical components, so it is a foundation to achieve automatic detection of circuit. Not only is this method economical and practical, but it also helps to gain a good effect in process of teaching.

The ALU of CMOS microcomputer have been designed with the 3um design rule for CMOS polysilicon gate and Its cells were layed out. The operation of circuits were simulated with EDAS_P. The widths and lengths of gates In the circuit were determined using SPlCE. The carry delay of the ALU was Improved by Manchester carry method. The results of logic and circuit simulation were in good agreement with expected circuit characteristics.