Reverse synchronization of 50MVA Coal fired turbine to 20MVA Grid station about distance of 2km between grid & turbine is very critical operation in power system. We use SICES controllers for turbine and grid in synchronization system. GC-600 & MC-200 Italian modules are used for generators control & mains control respectively.
The problems are it is very difficult to control high capacity turbine (50MVA) through Generator control module as GC-600 controller basically designed to control the Generators up to 10MVA capacity and the other main problem is communication between turbine & grid because the distance is too long (1.5KM) between them. Our innovation is we controlled the turbine through this Genset controller GC-600 by setting up different suitable parameters. We overcome the communication problem by using single mode fiber optic cable between controllers. After doing the research work we commissioned this project in a Maple Leaf Cement Factory, Mianwali.
I. INTRODUCTION & HISTORY
HIS document is about the reverse synchronization of coal fired turbine with grid station. ”In an alternating current electric power system, Synchronization is the process of matching the speed and voltage of a generator or other power source to a running network” 1. Maple Leaf cement factory import the 50MVA turbine from China. Total load of this factory is 65MVA. Factory working hours are 24/7. Before this they are taking all electric supply from WAPDA & 3 x HFO generators which were very costly. To overcome this cost they decided to make their own power house which can meet their energy requirements. For this purpose they import the 50MVA coal fired turbine. However, this turbine fails to meet the energy requirements when factory is running on full load. To run the factory on full load Maple Leaf took 20MVA connection from WAPDA supply & 50MVA from Turbine. After installation they need synchronization between WAPDA & Turbine to run the plant on full load. For synchronization they installed Woodward synch check relay to synchronize the WAPDA supply with the coal fired turbine. But they were doing manual synchronization. 2
Distance between the grid and coal fired turbine is about 1.5KM which is a biggest issue in synchronization. Usually in synchronization system Plants are not as much far away each other but this case is unique. In existing system they were doing the manual synchronization they have the selector switch for speed regulation and voltage regulation on the control panel of coal fired turbine. Whenever they have to synchronize the turbine with Grid supply they synchronize it manually. They communicate through phone call to up and down the speed and left the synch check relay on auto mode. By watching the speed form grid side they regulate the speed of turbine through selector switch. In this way Turbine takes lot of time to synchronize with grid even sometime they fail to synchronize this turbine. In manual synchronization there is no safety protection which are very necessary in synchronization of any source with grid that is ”Vector Jump Protection and R.O.C.O.F”. Without these protections plant is always on risk. It’s very dangerous for big plant to run without these. However, whenever they fail to synchronize the turbine with grid Maple Leaf ran into a huge loss. To overcome all of these problems we provide the solution of Reverse synchronization of coal fired turbine with the Grid station by analyzing all the problems which they are facing in detail. For synchronization we used the SICES controllers import from Italy, which are GC-600 3 and MC-200 controller 4.
GC-600 controller is basically designed to control the Generator but our innovation we used it to control the speed and voltage regulation of coal fired turbine (50MVA).
Figure 1 GC-600 Genset Controller
MC-200 controller is mains controller and is used to synchronize the grid supply with Generator or other source for parallel synchronization.
Figure 2 MC-200 Mains Controller
MC-200 controller and GC-600 controller communicate with each other through PMCBUS communication protocol. Distance between the grid station and turbine’s control room is almost 2KM. Normally the distance is about 12m for communication through 1.5mm flexible cable if we use the cable greater than 250m then controller lost the