It’s been a while since I’ve posted and a lot has happened on the project!
Unfortunately an engineer from Semikron emailed me back and there is no way to modify this SKAI circuit board to make it work. Despite the D-sub 25 connector, it is a completely separate circuit board compared to the board without the DSP. Semikron would also not provide me with circuit board schematics except for the DSP pinout, despite the SKAI manual saying that they do provide them. They suggested that I buy a new SKAI, but we are looking at $3500 for a model that would work on a motorcycle and a 12 week lead time. So that is not going to work.
The way ahead is either to use the DSP or to tap into the current sensing circuit, feed it to Tumanako board, and then have the Tumanako board feed the DSP with the gate signal. The 2nd option seems like it would be difficult due to the limited inputs on the SKAI board and the SPI speed constraints.
The negatives of using this DSP (TMS320LF2407A) is it is only 16-bit with no floating point. It also has little support from TI and limited libraries to make programming easier. It also only work with TI’s old Code Composer Studio v3 (v5 is the current version based on eclipse), and requires a CCS license to use it. I have emailed TI’s university program to see if they can provide a copy, the paid version is almost $500. Also it requires a special JTAG to program it, so I ordered a XDS510PP programmer off of ebay that should arrive by the end of the week.Since the SKAI (and Tumanako board) have inputs for an encoder I am planning on using a AD2S1205 R/D Converter on the development board that Analog Devices sells to convert the resolver signal from the eAssist motor to a 1024 line encoder signal. So I ordered the EVAL-AD2S1205SDZ and EVAL-SDP-CB1Z boards from Digikey.com. I will be hooking up the resolver to the eval board, and then outputting the A, B, and NM signals to my controller. This is a relatively expensive option, but I think it should work well and the eval boards will allow me to test out the chip for possibly a future custom board with it.
It took me way too much internet searching, but I found the female half of the plug that connects to the case of the motor and outputs the resolver signals:
Molex MX150 12 pin Female Plug 33472-1201
Molex MX150 18-20AWG Female Connectors for the Female Plug 33012-2002
Molex MX150 Cavity Plugs for the unused connector pins 34345-0001
Both Mouser.com and Digikey.com sell the connectors
I have also received almost of the wiring parts for the project and I have started wiring all of the batteries, fuses, disconnect, and contactor together. Below is a picture of the batteries wired together showing the 86V. I am using UPS batteries that were available for free to provide the voltage needed to test the project.
Speaking of testing, I have also been working on the setup I will use to load down the motor for testing. I already have an Agni 95-R DC motor that I am going to couple to the eAssist motor using sprockets and chain. To provide load on the Agni, and I going to get a two burner electric range that will allow for adjustable electric load using the normal heat adjustment knobs. The electric range is just made up of resistive elements and the temperature is controlled by an infinite switch. The switch disconnects with increased temperature, with a bi-metallic strip to break conductive connection across the terminals.
On Friday, 15APR13, my third report was due. This is the last report due before the final report. New in this report is Simulink schematics in Appendix A, and initial results from the testing in Simulink. If you are interested you can view a copy here.