RESEARCH


Trough research work, many devices and laboratory models have been developed in the Laboratory, and used for further experimental research, and verification of new ideas in the field of drives and control of electrical drives.
 

Prototype of current frequency converter with auto sequential current inverter.

On this prototype, a well known problem of operation stability of drive with current frequency converter and induction motor was analyzed. Analyses of scalar control algorithms  were performed with an intention to overcome the problem of overvoltage during transients. Upgrade of ÁP based control subsystem, made possible to investigate and develop original algorithm for field control of drive with current converter and induction motor. Algorithm for direct torque control of induction motor supplied from current inverter is currently researching.
 

Four-quadrant DC drive with thyristor control and field weakening.

Control system realized by combining analog and digital technique enabled research in the field of control techniques of a drive with wide speed range. On this device, the original solution for adaptive controller (β-controller), suitable for implementation in nonlinear systems was tested.
 

ÁP module.

An original module (Europe format card), suitable for drive control both in research and industrial application, was developed on the base of 16 - bit processor 80c196KC.
 

Voltage frequency converter.

The device is primarily designed for education, but can be used for research, too. On this device, the algorithm for induction motor speed sensorless control with only one current  sensor was tested and verified.
 

Universal control system for thyristor rectifier control UUSTI.

On the base of ÁP module, a device for complete control of thyristor rectifier was developed and tested. UUSTI can be modified for individual control of mono phase and three phase bridge rectifier, but also when two rectifiers operate in antiparallel connection. Current, speed, position or some of process variables controllers are incorporated in the device. UUSTI is primarily designed for electrical drives, either for realization of new ones, or for revitalization of existing. Also, it is possible to use this device for thyristor rectifiers of other purpose, like battery chargers and dischargers, electrolyses, uninterruptible supply system, etc.  UUSTI is developed within the Innovation  project financed from the Ministry of science and technology of Republic Serbia.
 

Current driven chopper.

Transistor two-quadrate current driven chopper, with original robust solution for transistor drivers. Suitable for middle power DC drives, which require high control accuracy, with specially high dynamic performances.
 

Drives as rational and high efficiency consumers.

In the period between 1997. and 2001., investigations and developing of converter for drives that should enable operation with unity power factor, with sinusoidal supplying current and possible recuperation, were performed. Within the research, a current driven rectifier was developed, which incorporated in the converter for electrical drives provides above mentioned characteristics. Prototypes of converters for DC motor and induction motor drives were realized. Within the research, algorithms for control of electrical drives operation according to minimum power criteria were developed. These researches were financed within the Strategic technological project with the support of Ministry for science and technology of Republic Serbia.
 

System for precise speed measurement using encoder.

Four-channel system for precise, simultaneous speed measurement in multi-motor electrical drives. The device connected with PC provide speed monitoring in long time intervals. Developed software enables analyses of results which can be used for checking of  synchronization of several drives, balance of drive mechanical parts, with the accurate detection of misbalanced parts.
 

Laboratory model of two-motors drive.

On this model, which consists of two induction motors mechanically coupled, algorithms for the control of multi-motor drive supplied from frequency converters are tested. Till now, possibilities for the control of load distribution in the case of coupled motors are investigated.