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We trial the By Ross Tester The first all-electric production road vehicle available in Australia 10  Silicon Chip siliconchip.com.au W hy would SILICON CHIP want to review a motorbike? Aaahh, this is no ordinary motorbike! As far as we know, the Vectrix Electric Motor Scooter is the first fully-battery-powered, road-registered production vehicle of any description on sale to the public in Australia. That is reason enough in itself. And with all the talk about saving energy, CO2 emissions and carbon footprints, we gladly accepted the offer of a week’s hands-on trial. We were interested in the Vectrix on two levels – first, how the electric bike compared to its petrol-powered equivalents, ie, how successful was the transition from traditional power to electric power and second (and more importantly to us as a technology magazine) the inner workings of the bike. What had Vectrix done where many others had tried but failed? Being the only holder of a motorcycle rider’s licence around here, yours truly was elected to evaluate it. One difficulty, being based on Sydney’s northern beaches, was that it had to be picked up from the western suburbs. Not being a regular motorbike rider in city traffic, I wasn’t at all confident about mixing it with 50km+ of Sydney roads and freeways. So I fronted the distributor’s factory with a large box trailer, loaded up the very heavy Vectrix (a very close fit!), ti ed it on securely and brought it back to the relative safety of the back streets of Brookvale. I’ll have more to say on the street tests shortly. Suffice to say that I also co-opted the services of some experienced (ie, every day) riders to share their opinions and experiences. Just to re-emphasise: the Vectrix is a fully legal, road-registerable, batterypowered bike. As such, it requires that the rider have both a motor cycle rider’s licence and motor cycle helmet to use on Australian roads. Vectrix aren’t an organisation to hide their light under a bushell. You can’t fail to see that the bike is electric-powered, even if you can’t hear it! The definition of a motor scooter, as far as we can tell, is “a light motor cycle with small wheels”. Well, light it ain’t, neither are its wheels particularly small at 14-inch and 13-inch (front and rear respectively). Fair-dinkum “bikes” also have a foot-controlled lever to select gears and, because the clutch lever is mounted on the handlebars, another foot-controlled lever for brakes. The Vectrix has neither of these because it doesn’t have a clutch. Both brakes are handlebar mounted, similar to a pushbike. So it’s not exactly a step-through; neither do you have a big fuel tank and throbbing motor between your legs. So, therefore, it’s somewhere in between a scooter and a bike. However, it is fairly large. And it’s a lot heavier than most bikes ridden by average riders: the Vectrix weighs in at about 210kg (that’s as heavy as some superbikes). A significant proportion of that 210kg is its NiMH batteries. The bike itself features a lightweight, heavy-duty aluminium frame (as shown in our exploded diagrams). The batteries, all 110 of them, sit low in the bike to assist its centre of gravity. Even so, I’d hate to drop this bike because it would be a pain to get back up*. A close-up look at the Vectrix They say first impressions count – if you didn’t know it was an electric bike (and failed to read that huge “electric” logo down the side!), you might think it was just another fairly large motorbike. But you’d be wrong. Vectrix insist it’s a “MAXI Scooter” but we think they are underplaying their hand; damning it with faint praise, if you will. siliconchip.com.au This X-ray view of the Vectrix shows the batteries (red) and the charger (orange). The batteries are housed in a heavy fibreglass “safety cell” – just in case. May 2008  11 SPECIFICATIONS PERFORMANCE Maximum Speed 100km/h Acceleration 0-80km/h in 6.8s 0-50km/h in 3.6s Range 110km <at> 40km/h COMPONENTS Braking Front and rear Brembo disc brakes Tyres Front: Pirelli GTS23 120/70-14 Rear: Pirelli GTS24 140/60-13 Fork: Marsocchi telescopic fork Suspension Sachs twin shocks Frame Lightweight aluminium DAaRT™ Patented multi-function throttle provides regenerative braking and slow-speed reverse BATTERY Type Capacity Voltage Maximum Current Discharge Cycles Estimated life Charger Recharge time Nickel Metal Hydride (NiMH) 3.7kWh 125V 275A 1700 10 years or 80,000km 1.5kW on-board, 110-240V AC 2 hours (80%) 5 hours (100%) MOTOR & GEARBOX Motor type Brushless DC, radial air gap Power 20.2kW peak 7kW continuous Torque 65Nm maximum 22Nm maximum continuous Gearbox Coaxial integrated rear-wheel mounted planetary gear drive ELECTRONICS Controller Instrumentation Communication DIMENSIONS Weight Wheelbase Seat Height Wheels Storage Capacity Carrying capacity OTHER Warranty Emissions 12  Silicon Chip DSP & IGBT all-digital electronic control and motor drive system One central analog display and two side LCDs, showing speed, odometer, battery charge, estimated range and system status Controller Area Network (CAN) Systems diagnostic and communication via laptop interface The battery pack is rated at 125V, 30Ah (3.7kWh) with the cells arranged in series to get the required output voltage. The cells are arranged in 3 levels x 2 rows with six temperature sensors and two voltage sensors constantly monitoring them. This occurs even when the bike is not being ridden, with fans used to keep the temperature down. As we went to press, Melbourne was having an autumn heatwave (40°C days) and on the bikes in use down there, the fans were doing overtime! High temperatures limit the battery’s ability to supply peak power and also interfere with the cooling during the charging process. Starting The Vectrix features an inbuilt antitheft starting procedure (starting is hardly the right word!). Unless you have the “GO” symbol on the instrument cluster, it won’t. Go, that is! To get it there, you need to turn the key to the appropriate position, wait until the on-board computer has cycled through its self-testing procedure, then squeeze the two brake handles in the right order. OK, so it’s not much of a security feature but unless you know about it, you won’t be riding the Vectrix anywhere. Needless to say, I forgot it when I first tried to ride the bike! Putting the kickstand down automatically disables the bike and you must go through the brake handle squeeze procedure again. Charging The Vectrix has a built-in 1.5kW 240V mains charger (it’s actually under the handlebars). All you need to do is release the luggage container under the seat (again with the main key), 210kg 1525mm 770mm Front 14-inch, Rear 13-inch Under-seat – 40l (1 full-face helmet) Glove compartment – 6l Top case – up to 47l 2 people (rider and passenger) 24 months (+24 with Plug&Go) Polluting – Zero CO2 – Zero Acoustic – negligible It might look like a conventional bike throttle. But turning it backwards selects slow reverse and/or braking regeneration. siliconchip.com.au take out the mains lead and plug it in to any standard power point. The on-board computer goes through a rather (visually) spectacular self-check routine (especially pretty at night!) then proceeds to fast-charge the battery pack at the appropriate rate. 80% charge is achieved in two hours but there is no problem in leaving the bike charging overnight – the computer ensures the batteries can’t be cooked by overcharging. Charging is a four-stage process. Initially, the computer does a pre-check to ensure all is well with the pack. It then undertakes a “conditioning” charge of around 3-4A. The third stage is the main charge, which is a constantcurrent charge of 10-12A, the precise rate determined by the computer from the battery’s initial charge level and also from the condition of the battery cells themselves. Finally, it enters a transition stage which, at 1-3A, can be regarded as a top-up. The inbuilt fans can start at any time during the charging process and will generally still be cooling the cells down next morning, even though the charge itself may have ceased some time before. At current (Sydney) standard electricity rates (12.87c/kWh), it takes roughly 50c worth of power to fully siliconchip.com.au charge the Vectrix. And if you have off-peak electric (5.39c/kWh), you could have a new GPO fitted to that circuit and the power charge would then reduce to about 21c. In a PowerSmart home, a similar reduction would happen automatically if you charged in the off-peak period (ie, 5.61c/kWh between 10pm and 7am). The bike also has an “accessory” socket for charging such things as mobile phones. The motor The 20kW (peak) motor is built into the rear wheel hub and is directly connected via the planetary gearbox. There is no chain or belt drive – often 1 2 the bane of petrol-powered bikes if only because of the frequent maintenance required. The motor is consistently described in Vectrix literature and websites as a “brushless DC” type which we believe is a misleading term. It’s a common error made where the motor supply is battery (DC). But we believe it’s misleading to describe any motor as a DC type when, as in this case, the motor is a variable-frequency, 12-pole 3-phase AC type. Speed control of this type of motor is achieved by varying the frequency via the DSP & IGBT electronic controller. For those who are interested, we explain this in more detail in the separate panel at the end of this feature. 3 11 4 10 5 6 9 8 7 1. Driver information LCD 2. Anti-theft indicator 3. Low battery voltage indicator 4. Battery level indicator 5. Vehicle power switch 6. Dual function throttle 7. Speedometer 8. Estimated range 9. Key (“ignition”) switch 10. Turn signal 11. Ready/Go indicator The instrument cluster is fairly typical bike, except for that big “GO” symbol on the lef t LCD display and the battery level indicator on the right. May 2008  13 Inset at left: the patented, hub-mounted SBC Parker brushless motor, driving a 6:1 planetary gearbox. The brushless motor is three phase, with 12 poles and 16 slots. It produces up to 20kW at 3000 RPM. The heart of the Vectrix – the Interface Control Module or ICM, which governs all operational aspects of the Vectrix, everything from the turn indicators to throttle settings and regenerative braking control. Microchip PIC microcontrollers are used throughout. The motor is governed so that it cannot exceed 100km/h. With a maximum motor speed of 3000 RPM, this means that the controller runs up to 300Hz to achieve the 0-100km/h speed range. It has a reverse gear! When I picked up the Vectrix, Tony, the Sydney agent carefully explained the starting procedure, throttle control and brakes – and their use. For the most part, the handgrip-based control is typical of any motor cycle throttle control – turn it towards you and the bike accelerates, all the way to maximum speed (there is no clutch nor user-controlled gearbox). But if you turn the throttle control in the opposite direction, the motor is put into reverse – from any speed. Quality Brembo brakes are fitted – but you’ll seldom use them! 14  Silicon Chip That might sound dangerous but its not – in fact, it’s a bona-fide way to control this bike. It was, in fact, one of the significant design features of the bike and is patented. As you might imagine, a reverse gear is very handy for slow-speed manoeuvring and parking but that is not its main purpose. Putting the motor into reverse while travelling forward introduces regenerative braking, not only slowing the bike but putting braking energy (which would normally be wasted as heat) back into the battery. The Vectrix specs claim up to 12% energy recovery. That mightn’t sound like much but if you’re approaching the 80km limit and you’re 10km from home, it could be a lifesaver! Tony further explained that for the first half hour or so, I would be using the front and rear disc brakes (Brembos) just like a normal bike. “But as soon as you get used to using reverse, you’ll probably never touch the brake levers again.” And he was right! It became almost second nature to reverse the throttle any time I needed to slow down. And it was so smooth. The only time I needed the handbrakes was when I took the Vectrix down my long, “S”-shaped, 1-in-3 driveway and found the reverse gear couldn’t hold it. Incidentally, going back up again the Vectrix was still accelerating nicely at the top! Not enough noise? We mentioned before the noise (or lack thereof) of the Vectrix. Just a bit of gearbox and engine whine on acceleration and quite quiet as you drive along at local street speeds. And believe it or not, that’s a down-side. Pedestrians don’t hear you coming as they would a bike or a car. During the few days of riding, Look mum – no CO2 (well, not from the bike, at least. Maybe a tad from the power station?). Vectrix certainly haven’t failed to target the “green” market. siliconchip.com.au I had to hit the anchors several times as completely oblivious pedestrians (many busily chatting away on mobile phones) stepped out into my path. What ever happened to “look right, look left and look right again”? Fortunately (and probably due to the fact that I was a pretty slow rider), I had the reaction time necessary to react so no harm was done (except perhaps to my heart rate). But it is certainly something all electric vehicle riders/ drivers will have to keep in mind as numbers increase. Then again, as any bike rider will tell you, the vast majority of pedestrians are idiots, followed closely by the majority of car drivers (particularly Volvo drivers with big ears and hats). Instrumentation The instrument cluster has three “dials”. Centre is the speedo/odometer, while on the left is the “readyGO” indicator, clock trip meter and estimated range indication. On the right is a large graphic instantly revealing battery state-of-charge – virtually a fuel gauge. Above are the indicators for left/ REGENERATIVE BRAKING NiMH BATTERY PACK SPEED CONTROLLER VARIABLE FREQUENCY VARIABLE VOLTAGE 125V, 3.7kWH 240V OUTLET ON-BOARD SMART CHARGER 3-PHASE BRUSHLESS MOTOR Fig.1: in principle, it’s pretty simple: a high voltage, high-current battery, a motor speed controller and motor and a battery charger. right turn, low battery warning, theft protection on/off, high/low beam and service required light. The left handlebar has the light switch, high/low beam, horn, plus turn signals and cancelling, The right has only the power on/off switch and, of course, the patented throttle control discussed earlier. Other riders I gave a couple of long-term motor bike riders the opportunity to take the Vectrix for a run. One (actually my son-in-law, who features on this month’s cover) has a couple of bikes, one not too different in capacity to the Vectrix and another, a superbike, not too different in weight but very different in performance. His reaction? “Wow!” Of course, it didn’t have anything like the acceleration or speed of the big bike but he thought it compared quite well to his 250cc. For him, it had plenty of lowend grunt and continuing acceleration and power. The reverse gear had him bemused, Radio, Television & Hobbies: ONLY the COMPLETE 00 $ 62 archive on DVD &P +$7 P • Every issue individually archived, by month and year • Complete with index for each year • A must-have for everyone interested in electronics This remarkable collection of PDFs covers every issue of R & H, as it was known from the beginning (April 1939 – price sixpence!) right through to the final edition of R, TV & H in March 1965, before it disappeared forever with the change of name to Electronics Australia. For the first time ever, complete and in one handy DVD, every article and every issue is covered. If you're an old timer (or even young timer!) into vintage radio, it doesn't get much more vintage than this. If you're a student of history, this archive gives an extraordinary insight into the amazing breakthroughs made in radio and electronics technology following the war years. And speaking of the war years, R & H had some of the best propaganda imaginable! Even if you're just an electronics dabbler, there's something here to interest you. NB: Requires a computer with DVD reader to view – will not work on a standard audio/video DVD player the handy handy order order form form Use the on page 81 of this issue on page 81 of this issue. siliconchip.com.au impAd_A4_outlines.indd 1 2/04/2008 9:47:50 AM May 2008  15 “Brushless DC” motor control – how does it work? +125V IGBT1 C IGBT3 IGBT5 STATOR DRIVE SIGNALS G E N A B C IGBT2 IGBT4 0V A PHASE GATE DRIVE SIGNALS FROM THROTTLE B PHASE GATE DRIVE SIGNALS S IGBT6 3-PHASE SYNCHRONOUS MOTOR (12 POLES) C PHASE GATE DRIVE SIGNALS ROTOR POSITION FEEDBACK SIGNALS SPEED CONTROLLER + The hub motor used in the Vectrix motorbike is variously described as a “brushless DC” and also as a “12-pole 3-phase” motor which is likely to confuse many readers. In reality, there is no such thing as a brushless DC motor. All DC motors have brushes and a commutator while brushless DC motors are actually 3-phase motors driven by a 3-phase variable frequency converter. For power ratings up to about 20kW, as used in the Vectrix, the motor can be regarded as a synchronous motor with permanent magnets providing the rotor field. Larger brushless motors can be regarded as induction motors. Synchronous motors are always locked to the rotating magnetic field produced by the stator but the rotor may lag the field by a small amount depending on the load. By contrast, induction motors are never locked to the rotating magnetic field and their speed is always less than the synchronous speed. This is measured as “slip” which is typically around 5% at rated load. Such a motor (4-pole) would have a rated speed of 1440 RPM compared to synchronous speed of 1500 RPM. The circuit above shows the general arrangement of the motor and its controlling electronics. The heart of the circuit uses six Insulated Gate Bipolar Transistors (IGBTs) powered by 125V DC from the NiMH battery pack. That much we know from the limited information in Vectrix literature. From here on we are speculating on just how it is controlled but the method is typical of brushless DC motors. Nor do we know if the motor is connected in star or delta configuration. Note that the IGBT symbols shown in the circuit above are not incorrect. They are typically, although not always, shown with arrows for the collector and emitter. Also note that the motor’s rotor is shown as having only two poles (N & S) whereas it actually has 12. The six IGBTs are driven with pulse-width modulation (PWM) signals to provide three sinewave averaged output voltages with 120° phase separation, ie, as for a normal 3-phase motor. The frequency of the outputs is varied between 1Hz and 300Hz, giving a maximum motor speed of 3000 RPM. Furthermore, since the motor’s impedance will vary in direct proportion to the frequency, 16  Silicon Chip A – + B – + C – the amplitude of the drive voltage must be reduced as the frequency is lowered. Note that the motor is rated at 7kW continuous but as with many (if not most) 3-phase motors, the peak power output is considerably higher at 20kW. The limitation will be due to power dissipation limits in the windings of the stator and power dissipation in the 3-phase converter. Peak currents from the battery pack can be as high as 275A. The PWM signals to give the variable sinewave outputs to the motor may be up to 25kHz or higher. The motor responds to the average value of the phase outputs (A, B & C) and ignores the pulse width modulation. For precise speed control, the stator will include three Hall Effect devices to give rotor position measurement. This will allow the speed controller to vary the phase-lead or phase lag of the rotating magnet field (produced by the stator winding) with respect to the magnetic fields produced by the of the rotor’s permanent magnets. With phase lead, the motor will provide power to the wheels via the planetary gearbox. With phase lag, the motor will become an alternator to provide regenerative braking. Alternatively, by changing the direction of the rotating magnetic field in the stator, the motor will drive the bike in reverse. (L.D.S.) siliconchip.com.au Vectrix Health Check Diagnostics When you put your Vectrix in for its six-monthly “Health Check” the dealer will use this diagnostic software, via the CAN BUS and accessed through a serial socket inside the glove box, to check that all is A-O‑K with the bike, the batteries and everything else! At that time, the dealer can tweak any parameter and also upload the latest firmware to your bike. As it is a brand new design, revisions will continually take place to make it perform better, adjust charging characteristics, prolong battery life, check operating temperatures and even fix bugs! In keeping with the very low running the first time he’d ridden a bike with one. But like me, he found it very easy to get used to and to use instead of the brakes. His test ride turned out a bit longer than intended, as his F250 truck broke down on the way to our photo shoot location – and he borrowed the Vectrix to ride home and back with tools! My other bike-riding friend commutes every day on his Triumph. He expressed reservations about the 80km range, until I asked him how far he rode to work and back. “Mona Vale to Chatswood, about 20km each way,” he said. Then the penny dropped – his ride was almost spot on the average bike commute of 40km per day which Vectrix research had shown. He could ride to work and back – with plenty of reserve if he had to go somewhere else. And if necessary, he could plug the bike in to a power outlet at work and charge (to 80%) in two hours for another 60km or so of range. When he thought about this, his comment was “They’ll sell squillions of these . . .” Now I’m not sure how many squillions there are to the boatload but I’m pretty sure the Australian distributors would love to hear this. cal and auto-electrical workshops. The Vectrix created quite a stir; the greasies and sparkies pouring out of their buildings, wanting to know all about it. Believe it or not, one guy even showed me an electric bike he had tucked away – a Chinese import that could not pass ADR rules, so it couldn’t be registered. He mainly uses it for the grandkids to ride around on his country property. He couldn’t believe that someone had actually released a road-registerable model – “at long last,” he said . The WOW factor SILICON CHIP is located in Brookvale, on Sydney’s Northern Beaches. As well as being the home of a number of surfboard manufacturers, our street is also an auto alley – plenty of open-to-the-street mechanisiliconchip.com.au My impression I loved it – on any number of levels. It’s easy and fun to ride and being electric, certainly turned heads (if they heard it!). The technology behind the Vectrix is clearly well thought out and well engineered. For the commuting or occasional short-trip bike rider, the Vectrix is a clear winner. Because it is electric powered, it offers quite a number of advantages over a petrol-powered bike – not the least of which is low cost of running and service. It’s not the bike you would take to tour Australia – unless you took it in tiny bite-sized chunks and had charging organised wherever you stopped. But then again, it was never intended for this market. Its other main disadvantage is its cost – at $15,950 plus on-road costs (dealer delivery, registration, CTP – likely to add another grand) it’s cost of the machine, Vectrix expect the dealer Health Check to be quite low in price – in the order of $65 or so . And no (sorry!), the Health Check diagnostic software will not be available to Vectrix users. significantly more expensive than the average bike a commuter might purchase. But that, to a large extent, is a feature of its “newness” – all leading edge products come at a premium (remember early computers, DVD players, plasmas, etc?). And it’s in a similar market position to the Tesla Roadster electric sports car in the USA, now being sold for $US100,000 and they can’t make enough! I would expect the price of the Vectrix to drop as (a) sales volumes increase – with higher volumes come economies of scale. So far, all Vectrix advertising has been word of mouth – and they are starting to sell); and (b) competition comes onto the market. I’ve heard a number of reports that many organisations in China are working hard to produce road-registerable electric bikes. If you’re looking for a fun bike to ride to work, uni, etc; don’t need long range; like the idea of very low running costs . . . look at the Vectrix. * Woops. Mea Culpa. As it turned out, I did drop it – would you believe as I loaded it back on the trailer to return it? And yes, it was a real pain to get back up. Sorry, SC Vectrix! Contact: Vectrix Australia 164 Rouse St Port Melbourne 3207 Ph: (03) 9676 9133 Website: www.vectrix.com (US site) May 2008  17