TK476 : Design And implementation of Bidirectional DC_DC Converter For Battery Charge And Discharge
Thesis > Central Library of Shahrood University > Electrical Engineering > MSc > 2015
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Abstarct: Many power electronic circuits, located on the way of battery, use a DC-DC BUCK converter to pass the power to the battery and they use a BOOST converter to pass the power towards the bus connected to an energy source.
The main objective of the project is to consider the performance of bidirectional half-bridge converter according to switching frequency and to use soft switching. From among the other components of this project are mentioned the amount of inductor and optimized switching capacitor and switching frequency for applied converters. In examination of inductor, the maximum and minimum current passing and its final volume have been mentioned and also the fact that it should not be so small because of the high amount of noises has been considered. In switching capacitor, connection and disconnection switching losses and developing a soft switching has been investigated at this time.
The power system in this project has been designed aimed at reducing the number of switches as much as possible and the power flow in the two sides, and a PID controller is used for controlling.
To make the power flow to both sides, special control method must be used. In this method, in addition to determination of the current flow direction control, over flow current due to the lack of voltage will be avoided. For this purpose CPM which is an appropriate method can be used in this project. In this way, in addition to the voltage of both sides, the feedback of inductor current should also be taken. Then, in the process of calculation, instead of the actual amount of flow in control loop we can use the approximation of the current which is obtained by the voltage of both sides and the duty ratio.
The overall design for the converter using CPM method is baxsed on input voltage and changes the load. During the calculations, analyzing the characteristics of the battery and result of simulation, it is revealed that we should use step by step change power towards the bus connected to photovoltaic for tests. However other tests have also been done, but the circuit is inherently of high quality against the rest of changes. According the observations the highest amount of effectiveness in the circuit has been found here.
With checking voltages and currents curve we see the CPM method is suitable for bidirectional converter. the new CPM with less the current feedback have same response.
Using parallel a little capacitor with a switch and DCM mode The circuit have a zero voltage switching; so that have loss less.
Keywords:
#bidirectional half-bridge converter #CPM control in DC_DC converter #half-bridge converter control #battery charging and discharging control #PV connection to the battery Link
Keeping place: Central Library of Shahrood University
Visitor:
Keeping place: Central Library of Shahrood University
Visitor: