University of South Wales Master of Sciences Thesis
Fig. 4.8 Boost converter output
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- Điều hướng trang này:
- MPPT Controller.
- Fig 4.10 MPPT sub-System Model Fig 4.11 MPPT Algorithm dI/dV -I/V (magenta)
| Fig. 4.8 Boost converter output
4.2.5. Maximum Power Point Tracking (MPPT) modeling As discussed in chapter 3, maximum power point is obtained by introducing a DC/DC converter in between the load and the PV panel. The duty cycle of the converter is changed till the peak power is obtained. The duty cycle guarantees the output resistance matching of the circuit and PV operates at the MPP. Here in this simulation, Boost converter has been used and for calculating the duty, the famous and simple algorithm of Perturbed and Observed (P&O) has been used. MPPT Controller. Maximum power point tracking by incremental conductance method + Integral regulator Maximum power point is obtained when dP/dV=0, where P= V*I. -> d(V*I)/dV = I + V*dI/dV = 0. -> dI/dV = -I/V. The integral regulator minimizes the error (dI/dV + I/V) Regulator output = Duty cycle correction. Standalone hybrid generation system for the remote area of Thar, Pakistan Fig 4.9 MPPT Model Figure below showing detailed model of the MPPT system implemented on the method explained in the chapter - 3 Fig 4.10 MPPT sub-System Model Fig 4.11 MPPT Algorithm dI/dV -I/V (magenta) Standalone hybrid generation system for the remote area of Thar, Pakistan 4.2.6. VSC converter The three-level VSC (blue blocks) regulates DC bus voltage at 500 V and keeps unity power factor. The control system uses two control loops: an external control loop which regulates DC link voltage to +/- 250 V and an internal control loop which regulates Id and Iq grid currents (active and reactive current components). Id current reference is the output of the DC voltage external controller. Iq current reference is set to zero in order to maintain unity power factor. Vd and Vq voltage outputs of the current controller are converted to three modulating signals Uref_abc used by the PWM three-level pulse generator. The control system uses a sample time of 100 ms for voltage and current controllers as well as for the PLL synchronization unit. In the detailed model, pulse generators of Boost and VSC converters use a fast sample time of 1ms in order to get an appropriate resolution of PWM waveforms. tải về 6.62 Mb. Chia sẻ với bạn bè của bạn:
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