RPi PMSM Motor Control - start of hardware section.

Signed-off-by: Pavel Pisa <pisa@cmp.felk.cvut.cz>

diff --git a/rpi-pmsm-control/index.html b/rpi-pmsm-control/index.html
index 3d93ba08c6c26af40e1a6da3d97ae1910438e427..d6e2aa759439f37c4ef5d6fe4448a5c6dafbfe50 100644 (file)
--- a/rpi-pmsm-control/index.html
+++ b/rpi-pmsm-control/index.html
@@ -42,7 +42,7 @@ only two independent quantities/scalars are needed to describe the currents
 or Voltages which are in the fact vector in the 2D space.The polar coordinates
 system can be used but a rectangular system of alpha, beta components is equivalent
 and easier for transformations computation.
-[[!img pxmc-pmsm-block.png size="300x" align=right alt="Basic PMSM control setup diagram from PXMC library documentation"]]
+[[!img pxmc-pmsm-block.png size="500x" align=right alt="Basic PMSM control setup diagram from PXMC library documentation"]]
 This transformation of the three phase
 system to the two orthogonal components vector is named according to its
 inventor Clark transformation. The waveforms in this 2D system are sine
@@ -55,9 +55,29 @@ introduced by Robert H. Park and the transformation is named according to him.
 The control in the D-Q coordinates is (almost) independent of actual rotor
 position and (in simplified outlook) separates reactive current (i<sub>D</sub>)
 from the active current (i<sub>Q</sub>) resulting in torque affecting rotor
-movement.
+movement. The simplified diagram of PMSM motor control ins included for ilustration
+(source <a href="https://www.pxmc.org/">PXMC</a> library documentation).
 </p>
-[[!img pxmc-pmsm-block.png size="300x" align=right alt="Basic PMSM control setup diagram from PXMC library documentation"]]
+
+<h2 id="hardware">Hardware</h2>
+<p>
+The RPi (and its BCM2835 SoC) is equipped with only single accessible
+PWM output and no peripherals suitable for incremental rotary encoder
+(IRC) signal processing are found on the board. Analog to digital
+converters are missing as well. The two extension boards with required
+peripherals and power stage have been designed and produced at <a href="http://www.pikron.com/" target="_blank">PiKRON</a> company.
+The first one includes Field Programmable Gate Array (<a href="https://en.wikipedia.org/wiki/Field-programmable_gate_array" target="_blank">FPGA</a>) <a href="http://www.microsemi.com/products/fpga-soc/fpga/igloo-e" target="_blank">IGLOO AGL125-VQ100</a> produced by Microsemi company. The design of logic programmed into FPGA has been implemented by Martin Prudek in a frame of his <a href="https://dspace.cvut.cz/bitstream/handle/10467/62036/F3-BP-2015-Prudek-Martin-Bp_2015_prudek_martin.pdf" target="_blank">bachelor theses</a>. The FPGA design includes:
+</p>
+<ul>
+  <li>SPI interface which connect peripherals to RPi board
+  </li>
+  <li>32-bit qudrate encoder (IRC) position counter based on design of Marek Peca's (<a href="https://rtime.felk.cvut.cz/gitweb/fpga/quadcount.git" target="_blank"> quadcount</a>)
+  </li>
+  <li>three PWM outputs with half-bridge enable enable signals
+  </li>
+  <li>finite state automata for acquiring current measuremts from analog to digital converter and filtering/decimation of multiple fast reads for slower RPi processing
+  </li>
+</ul>
 
 </div>