1.1 Background
The performance of power electronic converters can be studied using mathematical equations which describe the behaviour of the particular converter. For example, the load current and load voltage pattern for a single-phase full-wave diode bridge rectifier delivering power to a series-connected RāL load can be studied by developing and then solving the differential equation describing the behaviour of this converter. The power electronic converter supplying power to these loads can be developed either as a system model that duplicates the performance of this converter or as a circuit model using the actual power electronic semiconductor and other passive components.
The models developed in this book are system models that solve the equations describing the behaviour of the system. A relatively new concept known as the switching function concept is used to simulate the behaviour of the power electronic converters [1ā9]. At this stage, it will be appropriate to mention the difference between the system model and the circuit component-level model that is obtained by electronic circuit simulation software. While the system model solves the characteristic equation describing the behaviour of the system, circuit component-level models developed using electronic circuit simulators use the passive and active semiconductor component parameters, such as, for example, ON and OFF switch resistance, voltage and current gain values, parasitic or stray capacitances between junctions, junction potentials, inherent inductive reactance and so on arranged as a subcircuit (also called the equivalent circuit of the semiconductor component or the device) to solve a given power electronic converter. In the system models, the characteristic equation describing the behaviour of the system can be either algebraic or differential.
1.5 Book Outline
In this text book, interactive system models for power electronic converters have mainly been developed and are then verified using interactive circuit component-level models.
Chapter 1 provides the introduction. In Chapter 2, the method of developing and advantage of interactive modelling are presented with a power electronic converter example. Chapters 3 through 6 provide building of interactive system models for AC to DC, DC to AC, DC to DC and AC to AC converters respectively. In Chapter 3, system models for single-phase full-wave diode bridge rectifier (FWDBR), single-phase full-wave thyristor silicon controlled rectifier (SCR), controlled bridge rectifier (FWCBR) and three-phase FWDBR are presented. In Chapter 4, system models for continuous current conduction (180Ā°) mode and discontinuous current conduction (120Ā°) mode inverters and the three-phase sine-triangle carrier PWM inverter are presented. In Chapter 5, system models for second-order DC to DC converters such as buck, boost and buckāboost converters are presented. In Chapter 6, three-phase thyristor AC to AC controllers connected in series with resistive loads in star with isolated neutral and three-phase thyristor AC to AC controllers in series with resistive load in delta are presented. In Chapter 7, the system model for SMPS using a buck converter is presented. The system models for fourth-order DC to DC converters such as single-ended primary inductance converters (SEPIC), quadratic boost and ultra-lift Luo converters are presented in Chapter 8. Chapter 9 deals with system models for three-phase DCTLI, three-phase FCTLI, three-phase FLCHBI, multi-carrier sine-phase shift (MSPS) and multi-carrier sine-level shift (MSLS) PWM. Finally, system models of power electronic converters discussed in Chapters 3 through 9 are verified for performance using circuit component-level models in Chapter 10, where semiconductor and passive components from Simscape-Electrical, Power Systems and Specialized Technology block sets are used. An interactive component-level model and real-time SIL or PIL simulation of a single-phase half H-bridge sine PWM inverter is presented in Chapter 11.
In the system- and component-level models for these power electronic converters, it is the aim to simulate any given power electronic converter by entering the parameters of the converter into the appropriate dialogue boxes, without altering the inner details of the model. This easy-to-use system, and component-level models, save time and are suitable for virtual power electronic laboratory applications.
