02-09 Advanced DC Topics

Parallel & Series formulas

Resistance & Inductance

Series Resistors & Inductors

$\begin{aligned} R_{t o t a l} & = R_{1} + R_{2} + R_{3} + . . . \\ L_{t o t a l} & = L_{1} + L_{2} + L_{3} + . . . \end{aligned}$

Parallel Resistors & Inductors

$\begin{aligned} 1 / R_{t o t a l} & = 1 / R_{1} + 1 / R_{2} + 1 / R_{3} + . . . \\ 1 / L_{t o t a l} & = 1 / L_{1} + 1 / L_{2} + 1 / L_{3} + . . . \end{aligned}$

Capacitance

Series Capacitors

$1 / C_{t o t a l} = 1 / C_{1} + 1 / C_{2} + 1 / C_{3} + . . .$

Parallel Capacitors

$C_{t o t a l} = C_{1} + C_{2} + C_{3} + . . .$

Floating voltage

Circuit potential not referenced against a reference point

Car 12V system
Reference point is usually earth/ground

Battery internal resistance

Caused by internal components & chemistry

Higher resistance: lower output current, lower output voltage, higher heat generation

Buck-Boost converters

DC-DC voltage converters

Uses solid state components. No transformer needed.
Buck converter: lowers DC voltage
Boost converter: raises DC voltage

Rectifiers, Inverters

Converts between AC and DC

Rectifier: converts AC to DC
Inverter: converts DC to AC

Kirchhoff's Voltage and Current Laws

Alternative tools for circuit analysis

Derived from laws of conservation of energy. Generalises Ohm's Law.
KVL: The sum of all voltage drops and rises around any closed loop in an electrical circuit is zero
KCL: The sum of currents flowing into and out of a point is zero

Superposition

Alternative tool for circuit analysis

For linear circuits only
In general, F(x+y) = F(x)+F(y) and F(kx) = kF(x)

prev: 02-08 Watt's Law & Ohm's Law Exercises
next: 03-01 Introduction to AC, Alternating Current