Control strategies of distributed generation (DG) are search for different combination of DG and storage units in a microgrid. This paper grow a detailed photovoltaic (PV) array model with maximum power point tracking (MPPT) control, and produce real and reactive power (PQ) control and droop control for DG system for microgrid operation. In grid-related mode, PQ control is grown by ruling the active and reactive power output of DGs in agreement with assigned note.
In islanded mode, DGs are reserved by droop control. Droop control tool power reallocation between DGs based on predefined droop quality at any time load changes or the microgrid is connected/disconnected to the grid, while the microgrid voltage and density is manage at give levels. This paper presents results from a test microgrid system exist of a voltage source converter (VSC) integrate with a DG, a PV array with MPPT, and changeable loads.
The control plan are tested via two scenarios: the first one is to switch between grid-connected mode and islanded mode and the second one is to change loads in islanded mode. Through voltage, density, and power quality in the simulation under such two scenarios, the planned control plan can be display to work correctly and efficiency.
- Distributed generation
- Droop control
- PQ control
Fig. 1. Schematic of the microgrid.
Fig. 2. Schematic of the PQ control.
Fig. 3. Schematic of the droop control.
EXPECTED SIMULATION RESULTS:
Fig. 4. PQ control under grid-connected mode.
Fig. 5. Droop control for switching modes.
Fig. 6. Droop control for varying load.
In this paper a exact PV model with MPPT, and PQ and droop controllers is growth for inverter integrate DGs. The use of PQ control protect that DGs can generate certain power in agreement with real and reactive power references. Droop controller is growth to protect the quick dynamic frequency response and proper power sharing between DGs when a forced isolation occurs or load changes.
Compared to pure V/f control and master-slave control, the proposed control method which have the ability to operate without any online signal communication between DGs make the system operation cost-effective and fast respond to load changes. The simulation results get shows that the proposed controller is efficient in performing real and reactive power tracking, voltage control and power sharing during both grid-connected mode and islanded mode.
To fully represent the complication of the microgrid, future work will include the growth of hierarchical monitor for a microgrid exist of several DGs and energy storage system. The function of primary controller is to commit optimum power reference to each DG to match load balances and the secondary controllers are create to control local voltage and density.
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