Study On The Simulation Of Prime Mover And Governor Based On Virtual Instrument

In order to study the characteristics of the power system and monitor them, many experiments and investigation should be done. However, because of the particularity and security of it, doing experiments in the power system is greatly restricted. Dynamic simulation is one of the effective methods to solve this problem.The simulation of prime mover and governor is one of the most important parts of the power system dynamic simulation and it is also a part that should be considered when investigating the operation and transition process of the power system. The prime mover has a great influence on the static stability and transition process of the power system. And the governor has the influence not only on the static stability and transition process but also on the dynamic stability of the power system.In our institute, the dynamic simulation laboratory is being rebuilt and one of the important parts of it is to redesign and rebuild the prime mover and governor simulation. In this paper, theories of the simulation of prime mover and governor were analyzed thoroughly and a new device based on VI (Virtual Instruments) was designed.The device of prime mover and governor simulation, which uses digital control mode, is separated into three parts, that is, data acquisition, data processing and control signal output. The working process of the system is: The speed and current signals of the altered DC electromotor measured by sensors are sent into PC through data acquisition card after being managed by signal adjusting device. In the PC, LabVIEW calculates this datum and then the control signal is sent out to controll silicon trigger board, which controls the DC electromotor.The main parts of the paper are how to establish the mathematic model of prime mover and governor and how to realize the model. In the part of prime mover simulation, the technique of armature current feedback plus speed feedback is adopted to alter the mechanical character of the DC electromotor. In the part of governor simulation, the mathematic models of all parts of real governor are used. In order to keep the models consistent with the governor prototype to the most extent, the inertia compensating tache and the negative characteristics of governor are introduced in the simulation system. Bilinear transformation is adopted in this paper to discrete the mathematic model of the whole control system. Considering that LabVIEW is a novel graphic computer language, the practical realization of mathematical model in LabVIEW is presented in this paper.By comparing the simulation result in Matlab and LabVIEW, this design proves to be correct. The system can simulate the operation performance of the real prime mover and governor and can realize the flexible and affective control of prime mover.