Sunday, May 31, 2009

Moving the Instrumentaiton

Since the Synkromotive controller has its own motor speed limiter based on input directly from the Zolox sensor, I decided to clean up the instrumentation by removing the RPM gauge and moving the Link-10 E-meter onto the dashboard. While this removes some of the "coolness" factor without a tach, I like the more simplistic look as I tend to be a minimalist.

Here's the empty pillar pod with the gauges and wiring removed. I'll probably run the local Civic used-parts store and simply get a piece of replacement trim.

Here's where I moved the E-meter to. I can actually see it quite well when driving. It's sitting in the same hole where the defroster button used to sit. I simply carved a rectagular hole in the dash and moved the defrost switch down a few inches. It protrudes a bit, but still works fine.

In addition to moving the gauges, I wired up the "oil" light to the warning light on the Synkromotive controller. The oil light requires it's input wire to pull down to ground. Since the motor controller puts out a +12V signal when there's a fault, I used a simple transistor circuit (see the schematic at the end of this post) and drove the transistor gate through a 3.3K ohm resistor.

Synkromotive Potbox Issues and Temperature Faults

Over the past week, I've been able to give the Synkromotive controller some good real-world experience during my commute. The controller is very smooth and has several parameters to keep the battery pack healthy. I also like that the Synkro controller doesn't tap off the main pack for part of its power supply which has led to pack imbalances in the past. You can see several voltage-current graphs on the Synkromotive website here. Click on SynkView at the bottom. You'll have to install MS Silverlight to see the graphs. Click on Logfiles/Civic and then an .XML file on the right to see various drives.

One major issue I had was that the car tended to lurch when first starting up. This isn't too bad on the freeway, but can be a real pain when in stop-and-go traffic. Last Thursday I was driving home in hot weather in stop-and-go traffic on the freeway in the middle lane. The car seemed to get progressively worse during the drive home with its "lurch-starting."

About 2/3 of the way home, the controller faulted and just stopped the car dead in the middle of the freeway. I attempted to clear the fault and get the car started again by turning the ignition key off and on. I must have been impatient (sometimes it takes a full six seconds for the controller to precharge and be ready), but I wasn't able to clear the fault. Traffic was slow, and two kind men helped me push the car off the left side of the road. This was a somewhat unnerving experience, but I guess it's part of the game when trying out a Beta-test motor controller. After propping open the hood, removing the primary 12V power from the controller and hard-booting it, it seemed to start up again and I drove the rest of the way home.

The beta controller units have been having a few issues with noisy temperature sensors. During initial acceleration, the electrical noise tends to cause a spike in the temperature sensors, causing the controller to shut down. After I got home from this incident, I observed some of the potbox inputs (Ainput in the Smi window) and realized that I have a really crummy PB5 potbox. The resistance goes from zero ohms and jumps up erratically to 400 ohms or so and then goes smoothly up to 5K. With this new information, I was able to set the "zero throttle" point above the 400 ohm point which makes acceleration much smoother and bypasses the glitches in the potbox.

Yesterday, I was driving someone home in the Civic. Again, it was a hot day and we were in stop-and-go traffic. The controller faulted again and shut the car down. Fortunately my friend, who was in a hurry, could walk the remaining eight blocks home while I rebooted the system. Ives at Synkromotive gave me some updated firmware with some extra noise filtering on the temperature sensors. After running the car through the same route with the new firmware and doing some extra stop-and-go testing, I couldn't get the controller to fault again. We'll see what happens the rest of the week.

Despite the faulting condition, I've been extremely happy with the power, smoothness, logging and programmability of the Synkromotive controller. This is going to be a really good product when it hits the shelves in July.

Going to the Electrathon/HPV Event at PIR

Last weekend, I took the Civic-EV to Portland International Raceway to show it off at the Electrathon/Human-Powered Vehicles event there. Memorial Day weekend is the one weekend that PIR can't make any loud noises, so they actively recruit electric vehicles and bicycles of all types to race.

Here's Gary's Honda Insight EV with lithium ion batteries and an Siemens AC motor.

This shows some of the velomobiles (encased recliner cycles) present at the event. They really fly.

Here's my humble Civic next to Paul B's Corbin Sparrow.

It was really hot that weekend, but the new controller held up well on the freeway.

Saturday, May 23, 2009

Installing the Synkromotive Controller

I stopped by the Synkromotive shop this morning and picked up my beta-test controller that I've been wanting to try out. After running out and buying some more magna lugs and welding cable, I came home and removed the Belktronix controller and all the associated wiring.

With the old controller gone, I had to figure out how to place the new contactor and controller. Here's my mock placement. I placed the contactor slightly behind the controller to limit the cable lengths I would have to use and keep the high-voltage connections away from eager fingers. After the placement, I removed the piece of thick plastic below, drilled some mounting holes and bolted the controller and contactor in place.

This picture shows all the high-voltage 2/0 gauge cable hooked up. I was very fortunate that I could reuse all the old cables and simply crimp on new lugs. My purchase of 12 extra feet of 2/0 gauge cable was for naught, but I'm glad I got it anyway since the welding shop is only open on Friday.

The high-voltage connections on the Synkromotive controller are well thought out, especially if the controller is near the motor and parallel to it. The funny downside is that the connector bars are vertical instead of horizontal, forcing me to use less-common "L" lugs on the 2/0 cable to attach things. I'll have to give this feedback to Synkromotive.

Here's the preliminary installation. I don't have the motor RPM sensor hooked up yet, but I wanted to get the system going because there's an electric car show this weekend at PIR (we're demonstrating EVs along side the Electrathon and Human-Powered-Vehicle folks).

The Synkromotive controller is fully digital and has a USB port on the side. After firing up the user interface program, I was able to verify that everything was mostly operating. Given that this is a beta program, documentation is slim at best and full of bugs. I've already given much feedback regarding specific points in the document that cause confusion.

After checking all the voltages, I rotated the potbox by hand with the transmission in neutral and (Voila!) the motor spun. As of 11:30pm, I took it for a quick test drive around the block. The acceleration was very smooth; however, it wasn't as peppy as I had hoped. The amps never got above 150, so I'm guessing there's some calibration I need to do with the potbox. Anyhow, after 7.5 hours, I successfully swapped out the old controller for the new.

I'm a big fan of an uncluttered engine compartment. While the Synkromotive controller definitely has some wiring, the Belktronix system was a bit more out of control. Here's a bunch of the "spaghetti" that I removed with the older controller. I like seeing the removed chaos in a box.

Once I get the individual Soneil chargers, I can remove additional wiring and clutter without all the shunt balancer boards on top of each battery.

Whoosh, I'm liking this new controller! Tomorrow I'll tweak settings a bit more and see if I can take it on the freeway to PIR for the show.


Sunday, May 17, 2009

Installing a New Potbox

As with many EV projects, much time is spent waiting for parts. The replacement Soneil chargers haven't shown up yet. On a more positive note, Synkromotive figured out some of the glitches in their new beta controller, so one should be available this coming Friday. This new system will require a different potbox, contactor and other wiring.

I'm excited to install the controller, so I installed a new potbox to get ready.

Here is a view on the driver side in the engine compartment just above the engine mount. I'm going to use the two holes in the engine mount bracket to mount the potbox.

Here's the PB-5 potbox that I purchased from Bob Bath with an aluminum bracket bolted to it. I was fortunate enough to keep this around in my pile of parts because it fits very well.

Did you notice the shiny silver thing attached to the arm of the potbox above? I had difficulty trying to figure out how to attach the acclerator cable to the arm of the potbox. The guy at the hardware store suggested that I use one of these tiny cable clamps. The "U" bolts fit perfectly in the holes on the arm and I can clamp the cable down tightly.

Here's the potbox mounted in place. Notice how it's tilted slightly to the left and not in parallel with the E-meter DC-DC converter in the black box to the right. This is because the accelerator cable interferes with the top of the shock tower if the potbox is mounted inline with the car. This leftward tilt moves the cable just inside the shock tower so it hangs better.

Not only did I have to attach the acclerator cable to the potbox arm, but I needed to mount the housing on th end of the accelerator cable in something so the cable could pull against something. To accomplish this, I took a spare piece of 3/4" angle iron and drilled a 5/16" hole in one end, near the edge. I then cut out the hole with a hacksaw to get this keyhole-like shape. This will allow the cable housing to slide in at its narrow point but not pull out when I slide it forward so that the wider threads sit in this 5/16" hole. I also drilled a 3/16 hole in the other angle iron face to mount this tiny piece with an 8-32 by 1/2" bolt.

Here's a piece of flat bar that will hold the cable housing. The two holes on the left are the same distance apart as the two posts on the potbox. The hole on the right end is where I'll mount the tiny piece above so the cable has something to push against.

After sawing off the tiny piece from the end of the 3/4" angle iron, I mounted it to the flat bar with an 8-32 x 1/2" bolt and nylock nut to keep it from falling off. This will rotate a bit and allow the cable some play as the potbox arm swings back and forth.

Here's the above bar mounted to the potbox with 8-32 x 1/2 button-head bolts with lockwashers.

Here's the same picture above, but with the cable mounted in it. The trick is to get the bracket on the right in the correct place so that you can use the two adjusting nuts to properly tension the cable so it gives maximum throw and stops at the zero point on the potbox.

Stay tuned for Friday when, hopefully, the controller arrives.