diff --git a/uni/mmme/2051_electromechanical_devices/diodes.md b/uni/mmme/2051_electromechanical_devices/diodes.md new file mode 100755 index 0000000..6618fc0 --- /dev/null +++ b/uni/mmme/2051_electromechanical_devices/diodes.md @@ -0,0 +1,64 @@ +--- +author: Akbar Rahman +date: \today +title: MMME2051 // Diodes and Rectifiers +tags: [ diodes, rectifier ] +uuid: 21cf8e5b-d808-412c-bb71-d298cdb02b4f +lecture_slides: [ ./lecture_slides/MMME2051EMD_Lecture8.pdf ] +lecture_notes: [] +exercise_sheets: [] +--- + +Diodes are like one way valves for electricity --- they allow current to flow in the forward +direction but not in the reverse. + +Pure semiconductors are often intentionally doped by specific impurity to alter +its electrical properties. + +The most basic thing you can produce with this is the PN junction (or, a diode): + +![A PN Junction (diode) with its circuit symbol.](./images/vimscrot-2023-03-23T12:04:26,471475256+00:00.png) + + +![Real diode behaviour in orange, ideal in red.](./images/vimscrot-2023-03-23T12:06:05,423779641+00:00.png) + +- $I_\text{leak}$ is the current that is able to flow in the reverse direction. + It is a very small amount. +- Forward voltage, $V_f$, is the voltage required to move current forward. +- Forward bias impedance, $Z_f$, shows that the diode has a low resistance until a certain point. +- At a certain point a diode will fail to block the reverse voltage (DC blocking voltage) + +![A real diode can be approximated with this this of ideal components.](./images/vimscrot-2023-03-23T12:09:18,426229668+00:00.png) + +# Rectification + +![ElectroBOOM <3](./images/full_bridge_rectifier.gif) + +How the rectifiers work are stepped through in lecture slides (pp. 32-44) + +The most basic rectification is very wasteful: + +![](./images/vimscrot-2023-03-23T12:12:41,250590501+00:00.png) + +This produces a waveform like this: + +![](./images/vimscrot-2023-03-23T12:13:04,564941427+00:00.png) + +This is a step in the right direction but it is still very wasteful and not a smooth +voltage at all. + +A H-Bridge (full bridge) rectifier allows the negative cycle to be harnessed as well: + +![H-Bridge Rectifier](./images/vimscrot-2023-03-23T12:14:18,334219094+00:00.png) + +This produces a voltage like: + +![](./images/vimscrot-2023-03-23T12:15:03,479660034+00:00.png) + +Capacitors can be added to smooth out the voltage: + +![H-Bridge Rectifier with capactior](./images/vimscrot-2023-03-23T12:15:29,203766582+00:00.png) + +This produces a voltage like: + +![](./images/vimscrot-2023-03-23T12:16:11,795530248+00:00.png) diff --git a/uni/mmme/2051_electromechanical_devices/images/full_bridge_rectifier.gif b/uni/mmme/2051_electromechanical_devices/images/full_bridge_rectifier.gif new file mode 100644 index 0000000..1790083 Binary files /dev/null and b/uni/mmme/2051_electromechanical_devices/images/full_bridge_rectifier.gif differ diff --git a/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:04:26,471475256+00:00.png b/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:04:26,471475256+00:00.png new file mode 100644 index 0000000..17f5624 Binary files /dev/null and b/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:04:26,471475256+00:00.png differ diff --git a/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:05:43,047846090+00:00.png b/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:05:43,047846090+00:00.png new file mode 100644 index 0000000..e9d8071 Binary files /dev/null and b/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:05:43,047846090+00:00.png differ diff --git a/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:06:05,423779641+00:00.png b/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:06:05,423779641+00:00.png new file mode 100644 index 0000000..a9e4996 Binary files /dev/null and b/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:06:05,423779641+00:00.png differ diff --git a/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:09:18,426229668+00:00.png b/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:09:18,426229668+00:00.png new file mode 100644 index 0000000..f70c6c4 Binary files /dev/null and b/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:09:18,426229668+00:00.png differ diff --git a/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:12:41,250590501+00:00.png b/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:12:41,250590501+00:00.png new file mode 100644 index 0000000..7fec9b1 Binary files /dev/null and b/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:12:41,250590501+00:00.png differ diff --git a/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:13:04,564941427+00:00.png b/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:13:04,564941427+00:00.png new file mode 100644 index 0000000..a7e3596 Binary files /dev/null and b/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:13:04,564941427+00:00.png differ diff --git a/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:14:18,334219094+00:00.png b/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:14:18,334219094+00:00.png new file mode 100644 index 0000000..919971b Binary files /dev/null and b/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:14:18,334219094+00:00.png differ diff --git a/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:15:03,479660034+00:00.png b/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:15:03,479660034+00:00.png new file mode 100644 index 0000000..99d6a3f Binary files /dev/null and b/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:15:03,479660034+00:00.png differ diff --git a/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:15:29,203766582+00:00.png b/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:15:29,203766582+00:00.png new file mode 100644 index 0000000..6f586a8 Binary files /dev/null and b/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:15:29,203766582+00:00.png differ diff --git a/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:16:11,795530248+00:00.png b/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:16:11,795530248+00:00.png new file mode 100644 index 0000000..f19c76a Binary files /dev/null and b/uni/mmme/2051_electromechanical_devices/images/vimscrot-2023-03-23T12:16:11,795530248+00:00.png differ