Not sure if this is normal, broken, or weird. But under acceleration, climbing hills and sometimes cruising my battery seems like it doesn't know whether to charge or run. I have no idea how accurate the screen is on showing what the battery is doing. It bounces between running and charging. Hard to explain so I took a few videos of it happening. This is a good day, sometimes it's worse. [ame="http://s71.photobucket.com/albums/i139/guyrollz/?action=view¤t=video-2012-02-26-17-41-19.mp4"]video-2012-02-26-17-41-19.mp4 video by guyrollz - Photobucket[/ame] [ame="http://s71.photobucket.com/albums/i139/guyrollz/?action=view¤t=video-2012-02-26-17-40-35.mp4"]video-2012-02-26-17-40-35.mp4 video by guyrollz - Photobucket[/ame] This video best shows what happens. Doesn't matter if the battery is in the green or blue, same thing. [ame="http://s71.photobucket.com/albums/i139/guyrollz/?action=view¤t=video-2012-02-26-17-36-07.mp4"]video-2012-02-26-17-36-07.mp4 video by guyrollz - Photobucket[/ame]
OK, think of a toilet with the ball slightly misadjusted.* As it fills all is fine and it comes to a stop RIGHT at the top of the overflow tube and shuts off. Then a tiny bit over water goes down the tube and it restarts filling. Over and over. The Prius computers treat your HV battery the same way. All is well while you fill the battery until it get to the point the computers are happy it is full. (For my Prius, this varies by day, it wants to be fuller when cold) Now that it is full, the Prius tries to use some power and immediately decides it needs re-filling. Over and over again. This is normal, and means your computers are happy with the battery level. *I am certain there is a classier analogy, but I don't know what it is.
I would add an explanation of what appears to be a normal condition, the flickering of the yellow electrical power flow arrows, from a different perspective. First, some things to remember: * the Hybrid Synergy Drive's (HSD) operating algorithms are maximized for minimum pollution and then minimum fuel usage. * the accelerator, the "go-pedal," transmits requests for torque to the HSD. Torque at the wheels results in speed across the ground. * the electrical power flow display is only an approximation of what's really happening. The clearest example of this is that there are really two motor-generators (MG) not the single one shown. The interplay between the two is quite complex and is not shown. The HSD is constantly doing a balancing act between most efficient operation of the internal combustion engine (ICE) and requests for torque that are outside it's limits for efficiency. For small ICE torque excesses, the HSD uses the power split device (PSD) to send excess torque through MG1 via the PSD, now converted to electricity and onto the HV battery. If there is a small torque deficit, the HSD adds torque by way of electrical power from the HV battery via the MGs. From an efficiency point of view, it would be best to drive with no power being dumped to or taken from the HV battery; no yellow arrows and no mechanical->electrical->chemical->elec->mech conversion losses. This condition is hard to get, and harder to sustain. There are numerous really small changes in conditions that play havoc with the HSD's providing the exact torque to the wheels that is asked for: wind speed and direction, road undulations, small go-pedal position changes, to name a few. The bottom line is that the dancing yellow arrows are the HSD balancing ICE and HV battery power inputs to meet your instantaneous torque request. The HSD's found an ICE output that's really close, but it's tweaking ICE/HV battery inputs for max efficiency and min pollution. What's not to like?
