Power Electronics - Soliton1 and Xantrex XFR20-130

Two main projects (power electronics and battery pack) remain before achieving the first drive and EV grin.   The power control electronics effort began with the purchase of a Soliton1 controller from www.EVBimmer.com .  The Soliton1 is a 300 KW (400 HP) brushed DC motor controller that can operate with a battery voltage range of 9 to 340 volts DC.  The Soliton1 output can provide 1000 amps of maximum current. 

Picture DSC00530 showing the Soliton1 power controller.  This unit came with software version 1.053

To allow testing of the Warp 11 and the Soliton1 without a battery pack, a Xantrex XFR20-130 DC power supply was purchased from Ebay (picture below).  This unit can provide regulated voltages between 0-20 volts and continuous current up to 130 amps. 

Used together, the Soliton1 and the Xantrex will allow both bench top testing of the Soliton1 and direct operational testing of the Warp 11 and the BMW 325i drive train (including 5 speed shift testing).  There will be no danger of draining a battery pack while the Xantrex is in use  !!!
 

Picture of Xantrex XFR20-130 DC power supply which will provide a regulated 0 to 20 volts and a regulated 0-130 amps. 

The Xantrex power supply requires 240 volt AC input, so a power cord with a male plug adapter was assembled with parts from Home Depot.  The new power cord now allows the unit to be plugged into a custom 50 foot 10 AWG extension cord whose opposite end plugs directly into the clothes dryer outlet in the basement.  It is intended in the future to install a 240 volt wall outlet conveniently in the garage for use with a car charger when needed. 

A Throttle Position Sensor (TPS) was purchased from EVNetics  (picture DSC00593) and it was connected to the Soliton1 followed by software calibration (100% and 0% throttle positions) using a lap top computer.  When the TPS was later set at its minimum, the Xantrex was drawing at idle 0.72 amps (246 volts and 177 watts, P=EI) and it was providing to the Soliton1 zero volts and zero amps..  When the TPS was at 100% (maximum), the Xantrex was drawing initially 9.2 amps (246 volts and 2263 watts), but as the Warp 11 came up to speed, the input amperage dropped slightly to 9.06 amps (246 volts and 2229 watts).  At the same time, at 100% throttle, the Xantrex was providing to the Soliton1 initially 19 volts and 101 amps (1919 watts), but as the Warp 11 came up to speed, the Xantrex then provided 19 volts at 85.2 amps (1618 watts). 

                                  
                                    

Picture DSC00593 of the EVNetics throttle body showing the standard auto type three wire plug and socket.

An RPM sensor was also obtained from EVNetics for testing and it was temporarily installed on the accessories end of the 0.875 inch Warp 11 shaft (picture  DSC00592).  This sensor allows the Soliton1 to collect RPM data which can then be output on the lap top computer display.  At full throttle the Soliton1 indicated a maximum rpm of between 850 and 1150, but the data collection was not stable and further study will be necessary to learn what is causing the rpm bounce during the measurement.  It is intended to later use the 58 tooth OEM BMW harmonic damper for measurement of the motor rpms.  The harmonic damper signal can be sent directly to the dashboard instrument cluster to allow real time driver observation, but some electronics interface will be needed to allow the Soliton1 to understand the 58 pulses on/2 pulses off signal that the harmonic damper produces.



                                       

 

Picture DSC00592 of the 0.875" ID Aluminum exciter ring with four steel set screws as installed on the Warp 11 shaft.

The Soliton1 requires a 12 volt power supply that must be capable of providing up to 8 amps for the engagement of the contactors on start up.  During subsequent continuous operation only about 1 amp is then required.  A search on Ebay under "regulated transformer power supply for LED" provided several inexpensive choices and one that provides 12 volts DC/10 amps and cost $15 was selected.  This power supply will also be used to provide the 12 volt power required by the JLD404 Intelligent AH Meter.  After testing is complete, the BMW 325i accessories 12 volt lead acid battery will supply all the required 12 volt energy.

Picture DSC00599 showing the 12 volt/10 amp DC output power supply (120 AC input).

Shelves have now been added to the previously existing pallet racking that is adjacent to the 325i in the garage.  This work area will provide space for additional meters and oscilloscope as well as easy access to the Warp 11 and the BMW 325i's electrical components during testing.

Picture DSC00598 showing the two shelves of work space that was created on the pallet racks adjacent to the 325i.

After the future purchase of an electric power steering pump, the battery pack is expected to be the final major component investment.