Zeng Qingliang

Research on Control Strategy for Regenerative Braking of a Plug-In Hybrid Electric City Public Bus

Regenerative braking is an efficient method to achieve better fuel economy and lower emission. The control strategy of regenerative braking for one plug-in hybrid electric city public bus with ABS system is studied. Under Qingdao urban working cycle, the scheme of the regenerative braking system has been developed, the control strategy is given out and simulated. The ideal braking force distribution on front wheel and rear wheel are analyzed. In the control strategy, power is supplied by regenerative braking when lower braking intensity is required and by proportionally combination of regenerative braking and frictional braking deduced by fuzzy-logic control strategy when higher braking intensity is required. And front wheel with rear wheel frictional braking and unchanged motor torque are combined by ideal braking force distribution when braking intensity up to motor’s max torque. And the logistic upper & lower limit value of ABS controller is correspondingly adjusted. The results indicate that, the new control strategy for regenerative braking of plug-in hybrid electric city public bus with ABS system can recover more braking energy with good brake drive ability, and can cooperate with ABS system to guarantee braking safety. And it improves the braking directional stability of the PHEV bus. It also conforms to ECE laws and regulations. Especially under the situation of urban working cycle of Qingdao, the energy consumption can be reduced by 15¿¿20¿.

A monitoring and controlling system based on distributed industrial ring ethernet in coal mine

There are many different factors that influence the safe production of coal mine such as equipment factor, environment factor and artificial factor etc. At current, many coal mines all over the world have built up harmoniously independent mutually monitoring and controlling sub-systems based on variety communicate channels and protocols. In this paper, a monitoring and controlling framework model is built up based on industrial ring Ethernet in coal mine, four layers of network demarcation are put forward, and the method and steps of hardware and software integrates are discussed. At last, the design procedure of a drainage auto control sub-system is introduced according to the Ethernet communication technique.

Study on Reliability of Computer Network

Study on reliability of computer network has not formed a complete theoretical system yet. This paper has reviewed the major achievements and the trend of the reliability of computer network. At the same time it puts forward an integration availability concept of computer network, that is, capacity of network resources utilization in prescribed time under the network failure conditions.

Study on controlled rectification constant-voltage of the 42v rare-earth permanent-magnet generator on vehicles

Through the direction of tangential magnetic field, many blocks of rare-earth permanent-magnet materials are fixed to the pole-shoes slots of the generators rotor core by non-magnetic slot wedges,the polarity of the adjoining permanent-magnet material is opposite, N polarity and S polarity are arrayed alternately, which compose the tangential permanent-magnet rotor. The rotor core is fixed by die-casted antimagnetic aluminum bushing which is mounted to a axis, when the rotor rotates, magnetic field follows, the armature coil cuts magnetic curve and produces the electromotive force. Three-phase half-wave controlled rectification voltage regulator is designed, which is composed of reference circuit, comparator circuit, trigger circuit and rectifying circuit, both regulate the voltage and the current and put out direct current with stable voltage. The voltage instability, which is caused by the automobiles 42V permanent-magnet generator at wide speed and wide load, is settled.