Download MPPT and Voltage Balancing Control With Sensing Only Inductor

MPPT and Voltage Balancing Control With Sensing Only Inductor
Current for Photovoltaic-Fed, Three-Level, Boost-Type Converters
Abstract
The need for renewable energy sources is on the rise because of the acute
energy crisis in the world today. Renewable energy is the energy which comes from
natural resources such as sunlight, wind, rain, tides and geothermal heat. These resources
are renewable and can be naturally replenished. Therefore, for all practical purposes,
these resources can be considered to be inexhaustible, unlike dwindling conventional
fossil fuels. The global energy crunch has provided a renewed impetus to the growth and
development of Clean and Renewable Energy sources. Solar energy is a vital untapped
resource in a tropical country like ours. The main hindrance for the penetration and
reach of solar PV systems is their low efficiency and high capital cost. This project
investigates in detail the concept of Maximum PowerPoint Tracking (MPPT) which
significantly increases the efficiency of the solar photovoltaic system.
In this paper both photovoltaic voltage and PV current need to be sensed to
perform maximum power point tracking (MPPT) control. For three-level boost
converter, both capacitor voltages need to be sensed and an additional voltage
balancing control loop is required to balance the capacitor voltages. In this paper, the
MPPT control and the voltage balancing control with sensing only inductor current is
proposed. Both the MPPT and voltage balancing control will be achieved only by using
the proposed sampling strategy of sampling the inductor current values.
Drawbacks of existing system
 The system is not reliable for the change in the climatic condition.
 mppt algorithm is not implemented.
 High voltage stress.
 High cost.
 High switching losses.
 High ripple current.
Advantages of proposed system
 Low voltage stress
 Low inductor current ripple
 Low switching loss.
 Reduction of sensor count to save the cost.
Application
 AC-DC PFC application
 DC-AC PV applications
 Fuel-cell applications
 Wind energy application
 Grid connected converters
 Inverters