International Journal of Electrical Engineering & Education

A partially singular trajectory for a linear system with scalar control is assumed to have a single junction point, the singular control depending explicitly only on the state vector. An analytical relationship is established between the junction time and end states.

A real-time digital control environment, based on Intel iSBC386/21, to implement digital controllers is described. A human-machine interface package developed on a PC AT computer allows the operator to monitor the controller under development. Illustrative results for an adaptive power system stabilizer implemented and tested in this environment are given.

Rules and observations for the design of balanced digital controllers from their analog counterparts are given. A root range technique showing the mapping of analog controller roots into the digital domain is illustrated. The performances of the digital control systems resulting from different emulation techniques are compared.

A method of symbolic circuit analysis using Mathematica is reported. With the powerful symbolic manipulation capacity of Mathematica, symbolic circuit analysis is significantly simplified. The analysed circuits can be passive or active, with active devices modelled by nullors. Non-trivial circuit analysis examples are presented and the program list is given.

This paper examines the use of spreadsheets for the construction of the behavioral simulation of Arithmetic Units. It is shown that the spreadsheet is appropriate both for teaching and learning of different types of Arithmetic Units. These units can be simulated very simply by students during the lesson.

Window based applications are now widely used in Universities and Colleges, and in Electronic Engineering they are used for circuit simulation. It is a relatively simple matter to enhance assignments based on these packages with the addition of your Help Files to provide assistance for the completion of the assignment.

The paper describes a technique for representing state machines that is of value in introducing the concepts of sequential systems. Using a philosophy of implementing each element in a state diagram or algorithmic state machine directly as a circuit entity enables a system to be quickly simulated and verified.

In this paper, the transient stability limits of a synchronous machine for various initial loadings have been determined in terms of its steady-state stability limit.

Described are two models of a fixed pitch wind turbine drive train coupled to an induction generator compatible with the Electromagnetic Transients Program (EMTP). The models require wind speed or turbine torque changes. Model performance is studied on a 30 kW commercial arrangement.