Lecture 15 - Drive Cycles and Energy used per km - Part 1

00:26:40
https://www.youtube.com/watch?v=AgHtL-DPGkg

概要

TLDRLa vidéo se concentre sur la dynamique des véhicules, analysant les diverses forces impliquées lors de leurs déplacements, telles que la résistance aérodynamique, la résistance au roulement, et la force due à l'accélération. Elle explique comment ces forces influencent le besoin en puissance et en énergie des véhicules, incluant les deux-roues, trois-roues et petites voitures. L'importance des cycles de conduite standardisés est soulignée, ceux-ci étant essentiels pour comparer efficacement les différents fabricants de véhicules sur la base de l'énergie requise et de l'efficacité énergétique. La régénération d'énergie, qui convertit l'énergie cinétique en énergie récupérée, est aussi abordée, avec des exemples détaillés pour différents types de véhicules. Enfin, il est mentionné que des facteurs comme le poids du véhicule influent sur sa consommation d'énergie.

収穫

  • 🚗 Les dynamiques des véhicules analysent les forces lors du mouvement.
  • ⚙️ Forces prises en compte : aérodynamique, roulement, pente, accélération.
  • 🔋 Calcul de la puissance et énergie nécessaires pour les véhicules.
  • 📊 Cycles de conduite : outils de comparaison des performances.
  • ⚡ Importance de la régénération pour l'énergie cinétique.
  • 📈 Utilisation des données pour évaluer l'efficacité énergétique.
  • 🛵 Analyse inclut deux-roues, auto-rickshaws et petites voitures.
  • 🔍 Régénération : transformation de l'énergie cinétique en électrique.
  • ⚖️ Poids et aérodynamique influencent la consommation d'énergie.
  • 🚦 Vélocité et comportement sur cycles déterminent l'évaluation.

タイムライン

  • 00:00:00 - 00:05:00

    En dynamique des véhicules, les forces sur un véhicule en mouvement incluent la résistance aérodynamique, la résistance au roulement et la résistance au gradient. On calcule la force pour accélérer le véhicule et, donc, la puissance requise, ce qui permet d'estimer l'énergie nécessaire. Ce concept s'applique aux cycles de conduite pour comparer différentes marques, comme dans les cycles de conduite standardisés pour évaluer la performance énergétique.

  • 00:05:00 - 00:10:00

    Le cycle de conduite donne des informations sur la vitesse et l'accélération à chaque instant. Cela permet de créer des feuilles de calcul pour calculer à chaque seconde la distance parcourue, l'accélération, la force nécessaire à l'accélération, et autres forces résistantes. On intègre ensuite la puissance pour obtenir l’énergie consommée. La régénération d'énergie est introduite pour estimer l'énergie restituée et ainsi ajuster la puissance requise.

  • 00:10:00 - 00:15:00

    Pour les cycles de conduite comme l'India Drive Cycle pour deux-roues, on peut calculer la consommation d'énergie et l'impact de la régénération énergétique à différents niveaux. Bien que ce cycle standard n'inclut pas de pente, des exercices additionnels incluent cet aspect. On utilise la feuille de calcul pour calculer les besoins en énergie basé sur les différents paramètres du cycle de conduite.

  • 00:15:00 - 00:20:00

    Dans le cadre de calculs pour l’auto électrique, on voit que la consommation est réduite grâce à une régénération énergétique efficace. Les facteurs influençant l'efficacité énergétique incluent, entre autres, la masse totale du véhicule, et des améliorations peuvent venir de la réduction du poids ou des améliorations aérodynamiques. Les inefficacités dues au contrôleur du moteur doivent aussi être prises en compte pour une estimation complète.

  • 00:20:00 - 00:26:40

    L'étude inclut aussi les e-rikshaws où la vitesse est limitée pour des raisons réglementaires. Les cycles de conduite mesurés montrent une grande influence de la régénération et des paramètres variés, comme la masse ou la résistance aérodynamique. L'énergie par kilomètre est estimée et comparée à l'efficacité attendue d'autres types de véhicules, soulignant l'importance des conditions d'utilisation et des spécificités techniques du véhicule.

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ビデオQ&A

  • Quels sont les principaux concepts abordés dans la vidéo?

    On évalue des concepts comme la résistance aérodynamique, la résistance de roulement, l'énergie et la puissance requise, ainsi que les cycles de conduite pour comparer différents véhicules.

  • Quel est le rôle d'un cycle de conduite?

    Les cycles de conduite permettent de comparer la performance énergétique de véhicules similaires sur des parcours standardisés.

  • Quelles méthodes sont discutées pour améliorer l'efficacité énergétique?

    Il est montré que différentes méthodologies comme la régénération et l'optimisation des poids peuvent améliorer l'efficacité énergétique.

  • Quels types de véhicules sont discutés pour l'analyse énergétique?

    Les véhicules électriques étudiés incluent des deux-roues, des auto-rickshaws, et de petites voitures.

  • Que signifie la régénération d'énergie dans ce contexte?

    La régénération d'énergie convertit l'énergie cinétique ou potentielle libérée pendant le freinage ou la descente en énergie électrique récupérée dans la batterie.

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  • 00:00:02
    [Music]
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    [Music]
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    before we proceed ahead
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    let us quickly capture what we have done
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    so far
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    on vehicle dynamics what we did is that
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    at vehicle when it is moving
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    we looked at all the forces that are
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    applied to the vehicle
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    the aerodynamic resistance
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    the rolling resistance the gradient
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    resistance
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    and the force due to acceleration when
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    we accelerate it
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    that gave us the total force
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    that is required for the vehicle to
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    accelerate at a certain point
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    and run at a certain velocity
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    we are able to compute this for all
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    kinds of vehicles two wheelers three
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    wheelers
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    four wheelers and even small trucks we
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    were able to compute that
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    what we did is that once we knew the
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    force
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    we said well we also know therefore
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    what is the power required because the
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    force multiplied by the
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    velocity gave us the power
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    and when we took the power got the power
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    we could also integrate and find out the
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    energy required
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    that is something that we have done
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    at the same time once we knew the force
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    at any state we also knew
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    what the torque requirement is
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    and at different speed what the torque
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    requirement will be
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    what the power requirement will be and
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    we also got the energy required
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    this is what was a fundamental that we
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    had to do
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    to get things going
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    after that what we did
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    in the last class we introduced the
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    concept of a drive cycle
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    said this is fine but
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    if i want to compare some manufacturers
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    to wheeler
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    to another manufacturer's two wheeler
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    we can compare that that how much energy
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    does that two wheeler takes to
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    carry out a drive and a similar drive
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    how does the
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    another two wheeler takes
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    so the concept of similar drive came in
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    and we sort of said that world over
  • 00:02:57
    there are various
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    entities regulators
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    which define some standard drives
  • 00:03:07
    and you have to obtain the performance
  • 00:03:11
    of the vehicle
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    as per that drive and that drive
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    is the drive cycle and we introduced the
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    concept of driver cycle
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    and we said based on that drive cycle we
  • 00:03:23
    can compute what is the maximum power
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    required what is the torque maximum
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    torque required
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    what is the maximum energy what is the
  • 00:03:29
    energy required
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    what is the energy efficiency watt hour
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    per kilometer
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    will figure out all these things and
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    we introduced this concept
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    slowly and then we defined
  • 00:03:43
    the first standard drive cycle the two
  • 00:03:46
    wheel air
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    drive cycle called india drive cycle now
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    different cities may have different
  • 00:03:51
    drive cycles
  • 00:03:52
    why because in different cities the
  • 00:03:55
    roads may be of different kind
  • 00:03:57
    the slopes may be there or not there
  • 00:04:01
    in different cities you may have traffic
  • 00:04:03
    moving at different speeds
  • 00:04:06
    but there is a india drive cycle which
  • 00:04:08
    is widely used
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    to compare one two wheeler with another
  • 00:04:13
    pretty much around the country
  • 00:04:15
    and we defined this what
  • 00:04:18
    this cycle was the drive cycle what did
  • 00:04:20
    we do we sort of say every instant of
  • 00:04:23
    time
  • 00:04:24
    what is the velocity at which it travels
  • 00:04:30
    next instead of time what is the
  • 00:04:31
    velocity at which it travels
  • 00:04:33
    so we are able to also figure out what
  • 00:04:35
    is the acceleration required
  • 00:04:38
    and for how long does it travel at that
  • 00:04:41
    velocity or with that acceleration
  • 00:04:43
    we are able to figure out and once that
  • 00:04:46
    table
  • 00:04:46
    is created that every instant
  • 00:04:50
    and i sort of say we can take it every
  • 00:04:52
    second we can take it
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    every half a second we know exactly how
  • 00:04:56
    the vehicle is
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    moving once we know exactly how the
  • 00:05:01
    vehicle is moving that is what the drive
  • 00:05:02
    cycle tells us
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    a standard drive cycles then we
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    start using whatever we had
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    learned so far to create a spreadsheet
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    where you sort of say every second what
  • 00:05:17
    is the distance that it will travel what
  • 00:05:19
    will be the acceleration
  • 00:05:21
    what is the force required due to
  • 00:05:23
    acceleration
  • 00:05:24
    what is the rolling resistance force
  • 00:05:27
    what is a drag force required
  • 00:05:29
    and therefore we added all this what are
  • 00:05:32
    the traction force required
  • 00:05:34
    and we computed also traction torque
  • 00:05:38
    and then we computed what is the power
  • 00:05:41
    required to move at that
  • 00:05:42
    second and then we integrated the power
  • 00:05:46
    and obtain the energy and we said this
  • 00:05:49
    can be very nicely done
  • 00:05:50
    on a spreadsheet
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    all right now if you notice in this what
  • 00:05:57
    i have not done
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    is the slopes because the india drive
  • 00:06:01
    cycle does not define the slope
  • 00:06:02
    but in one of the assignment problem
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    that i gave you i actually included the
  • 00:06:06
    slope
  • 00:06:08
    so the spreadsheet will change a bit
  • 00:06:11
    will include one more force called the
  • 00:06:14
    force due to climb force due to gradient
  • 00:06:17
    and you have to add that and do the need
  • 00:06:19
    for
  • 00:06:21
    and based on that we took defined a two
  • 00:06:24
    wheeler we have to define all the
  • 00:06:26
    parameters for the two wheelers
  • 00:06:27
    something that we have been doing for
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    the last so much time
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    and said we will do every second this
  • 00:06:33
    compute
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    and we actually computed and started
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    putting the spreadsheet
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    in fact an assignment i have asked you
  • 00:06:41
    to build a spreadsheet here we have only
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    used the spreadsheet
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    we then are able to figure out the
  • 00:06:47
    velocity at which
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    every second how much it will travel uh
  • 00:06:50
    the incremental velocity
  • 00:06:52
    incremental velocity ah for incremental
  • 00:06:55
    distance travel and similarly the
  • 00:06:56
    distance
  • 00:06:57
    incremental distance that is traveled
  • 00:06:59
    once we are able to figure this out
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    we then are able to also figure out the
  • 00:07:03
    power the
  • 00:07:05
    power the torque the total
  • 00:07:08
    force torque power and we are able to
  • 00:07:11
    integrate and get the energy
  • 00:07:13
    and we also introduce the concept of
  • 00:07:16
    regeneration
  • 00:07:17
    if there is 100 percentage regeneration
  • 00:07:18
    what is the energy consumed
  • 00:07:20
    it is a 30 percent regeneration what is
  • 00:07:22
    the energy consumed all this we have
  • 00:07:24
    done it
  • 00:07:25
    and we are able to then plot
  • 00:07:28
    what is the energy consumed and this is
  • 00:07:31
    with hundred percent
  • 00:07:32
    regeneration you can see that while
  • 00:07:35
    energy consumed is high
  • 00:07:37
    up to around 83 seconds and then
  • 00:07:41
    you are able to recover the energy why
  • 00:07:43
    are you able to recover the energy
  • 00:07:44
    because
  • 00:07:45
    right now after that it is at the peak
  • 00:07:47
    speed and slowing down
  • 00:07:49
    this is assuming all the deceleration
  • 00:07:53
    energy is converted
  • 00:07:54
    back to the energy electrical energy
  • 00:07:58
    and put into the battery within saucer
  • 00:08:01
    well that is not always so
  • 00:08:03
    so we introduce the concept of
  • 00:08:04
    regeneration and say
  • 00:08:06
    if i take only 50 regeneration
  • 00:08:10
    then the energy consumed would be little
  • 00:08:12
    more
  • 00:08:13
    and we actually introduced that in the
  • 00:08:15
    spreadsheet we cannot change the
  • 00:08:17
    regeneration to be 30 percent
  • 00:08:19
    or 10 percent or even nothing and we are
  • 00:08:22
    able to compute
  • 00:08:25
    what is the energy per kilometer in
  • 00:08:28
    every single case
  • 00:08:32
    all right this is something that we did
  • 00:08:33
    for two wheeler
  • 00:08:35
    so we essentially have got the hang of
  • 00:08:38
    it
  • 00:08:38
    why did we do individual forces why did
  • 00:08:41
    we look at the total traction force
  • 00:08:44
    why did we look at the total torque the
  • 00:08:47
    total power
  • 00:08:48
    and energy now combined with the drive
  • 00:08:51
    cycle we are able to figure out
  • 00:08:53
    what does it take what is the energy
  • 00:08:55
    that it takes
  • 00:08:57
    now remember that we have not taken into
  • 00:09:00
    account
  • 00:09:01
    the inefficiencies inefficiency due to
  • 00:09:04
    motor
  • 00:09:05
    and motor controller that will be one of
  • 00:09:07
    the major inefficiency
  • 00:09:09
    you lose a certain amount of energy as a
  • 00:09:11
    result of that that will
  • 00:09:12
    so your water per kilometer will change
  • 00:09:15
    we didn't take into account
  • 00:09:17
    the energy required for all kinds of
  • 00:09:20
    other things like
  • 00:09:21
    lights or air conditioning
  • 00:09:24
    you may have to include that in which
  • 00:09:26
    case you will consume more energy per
  • 00:09:28
    kilometer
  • 00:09:29
    so all these things we will be looking
  • 00:09:31
    at it
  • 00:09:32
    but what will now do is pretty much
  • 00:09:35
    repeat the exercise
  • 00:09:37
    almost repeat so will go fairly rapidly
  • 00:09:40
    drive cycles and energy used per
  • 00:09:42
    kilometer for first an
  • 00:09:43
    auto then an ericsson
  • 00:09:46
    and then a compact sedan remember
  • 00:09:50
    that for a two wheeler that was a little
  • 00:09:52
    low end two wheeler
  • 00:09:53
    how we didn't go about 45 kilometer also
  • 00:09:57
    that drive cycle does not go above 45
  • 00:09:59
    kilometer
  • 00:10:00
    it was it could consume between 13 to 17
  • 00:10:03
    water per kilometer
  • 00:10:05
    not taking in efficiencies into account
  • 00:10:08
    so total energy consumed depending on
  • 00:10:11
    the regeneration and if you
  • 00:10:15
    take the inefficiencies it will still be
  • 00:10:17
    under 20
  • 00:10:19
    watt hour per kilometer
  • 00:10:23
    so a two wheeler essentially is like a
  • 00:10:26
    20 watt bulb
  • 00:10:31
    remember its actually consumes very
  • 00:10:32
    little electricity
  • 00:10:36
    once you are able to build that we can
  • 00:10:38
    do things quite well
  • 00:10:40
    let us now look at an auto if i look at
  • 00:10:44
    auto one of the major thing is the mass
  • 00:10:48
    changes the cross vehicle weight
  • 00:10:51
    because number of passengers will be
  • 00:10:53
    about three passengers plus the driver
  • 00:10:55
    that itself will consume quite a bit
  • 00:10:56
    then the vehicle the
  • 00:10:58
    gravity is going to be same rolling
  • 00:11:00
    resistance
  • 00:11:01
    drag all these parameters we have seen
  • 00:11:04
    air density same 1.2 kilogram per meter
  • 00:11:08
    cube
  • 00:11:08
    projected area is 1.6 meter square
  • 00:11:11
    we will use the drive cycle idc auto
  • 00:11:15
    and idc auto is same as the drive cycle
  • 00:11:18
    for idc two wheeler
  • 00:11:20
    so we will use that wheel radius is
  • 00:11:23
    point two meters
  • 00:11:24
    smaller radius and we take regeneration
  • 00:11:28
    efficiency 0.5 will actually
  • 00:11:30
    vary that and as i pointed out we will
  • 00:11:33
    use the same drive cycle
  • 00:11:36
    now one can change the drive cycle and
  • 00:11:38
    redo the computation all that it means
  • 00:11:40
    is that in the spreadsheet
  • 00:11:44
    the velocity at different seconds will
  • 00:11:47
    become different
  • 00:11:48
    so if you do that you do the same thing
  • 00:11:50
    no different
  • 00:11:52
    you start with at different time one two
  • 00:11:55
    three four five six seven eight
  • 00:11:57
    now why have i not shown z after zero
  • 00:12:00
    straight away sixteen seconds because
  • 00:12:02
    zero to fifteen second is supposed to be
  • 00:12:04
    idling
  • 00:12:06
    so everything will be zero zero zero i
  • 00:12:07
    just not shown it out here
  • 00:12:11
    from 16 second onwards you see the
  • 00:12:14
    velocity is going on increasing
  • 00:12:16
    i put the kilometer per hour we can
  • 00:12:18
    convert it into meters per second
  • 00:12:21
    we actually compute the distance that it
  • 00:12:24
    travel
  • 00:12:24
    and the acceleration we actually compute
  • 00:12:27
    all of this
  • 00:12:28
    and if you plot this the same plot that
  • 00:12:31
    you saw
  • 00:12:31
    because the same drive cycle this is the
  • 00:12:35
    actual velocity at every second
  • 00:12:39
    it starts goes to top velocity 42
  • 00:12:42
    kilometer per hour
  • 00:12:43
    and goes to zero and this gives you the
  • 00:12:46
    incremental distance
  • 00:12:48
    and if you integrate the total distance
  • 00:12:51
    you find that you travel 658 meters
  • 00:12:53
    now the 658 meter is a single drive
  • 00:12:56
    cycle in about
  • 00:12:58
    108 seconds two minutes now you keep
  • 00:13:00
    repeating it six or eight times i had
  • 00:13:02
    done that
  • 00:13:02
    that's how you actually do the
  • 00:13:04
    performance measurement
  • 00:13:07
    this is for an auto now let us look at
  • 00:13:10
    what is the energy consumed
  • 00:13:11
    and this time i am not getting into the
  • 00:13:14
    details the same
  • 00:13:15
    the spreadsheet will give you it will
  • 00:13:17
    give you
  • 00:13:19
    from the velocity and acceleration
  • 00:13:22
    you will be able to then figure out what
  • 00:13:25
    is the
  • 00:13:26
    force due to rolling resistance force
  • 00:13:30
    due to aerodynamic resistance
  • 00:13:33
    no slope i have not taken so that is
  • 00:13:35
    ignored
  • 00:13:36
    force due to acceleration because
  • 00:13:37
    acceleration value that i have
  • 00:13:39
    i calculate the traction force and after
  • 00:13:42
    traction force i will actually compute
  • 00:13:45
    the torque on one side and power on one
  • 00:13:48
    side
  • 00:13:49
    and then i will integrate the power
  • 00:13:53
    that will give me a energy consumed and
  • 00:13:56
    remember
  • 00:13:57
    that when i am decelerating or climbing
  • 00:13:59
    down
  • 00:14:00
    in this case there was no climbing down
  • 00:14:02
    then i get negative
  • 00:14:04
    energy consumed now here i have to put
  • 00:14:07
    in the factor
  • 00:14:08
    what is the regeneration efficiency as i
  • 00:14:11
    do that
  • 00:14:12
    i actually get this and this this
  • 00:14:15
    is the energy required if you take
  • 00:14:19
    0.5 if you take hundred percent
  • 00:14:22
    energy efficiency you get this
  • 00:14:25
    and this is the energy required
  • 00:14:29
    if you take into account the
  • 00:14:32
    regeneration efficiency of 0.5
  • 00:14:36
    so you actually find out that the total
  • 00:14:40
    energy required if i take
  • 00:14:42
    regeneration of approximately ah 50
  • 00:14:45
    percent
  • 00:14:47
    which is by the way high i told you that
  • 00:14:48
    25 to 30 percent is what we'll actually
  • 00:14:50
    get
  • 00:14:51
    it is about 26.64 watt hour that's the
  • 00:14:54
    total energy consumed
  • 00:14:56
    you have traveled 658 meters we had just
  • 00:14:59
    seen
  • 00:15:00
    so you actually consume in auto
  • 00:15:02
    approximately 41 watt
  • 00:15:04
    per kilometer assuming 50 percent uh
  • 00:15:07
    regeneration
  • 00:15:08
    if you took 100 gen regeneration then
  • 00:15:11
    you will only consume 30
  • 00:15:13
    wattage per kilometer what does it mean
  • 00:15:16
    i'll challenge the people who design
  • 00:15:18
    motor
  • 00:15:20
    get me a motor which comes closer to 100
  • 00:15:22
    percent regeneration
  • 00:15:25
    it's a big gain if you can get
  • 00:15:29
    remember from 40 to 30 what does it mean
  • 00:15:32
    we actually consume only three fourth of
  • 00:15:35
    the energy
  • 00:15:37
    my battery size can therefore goes down
  • 00:15:39
    by three fourth
  • 00:15:42
    well but this is the theoretical
  • 00:15:44
    efficiency this
  • 00:15:45
    required simply to move we have just
  • 00:15:48
    taken the rolling resistance
  • 00:15:50
    and the aerodynamic resistance
  • 00:15:53
    inefficiency will be in top of it
  • 00:15:54
    so we'll actually consume about fifteen
  • 00:15:56
    percent to twenty percent more
  • 00:15:58
    there also depends on the motor and
  • 00:16:00
    controller depends on the battery
  • 00:16:02
    we look at some of those things
  • 00:16:05
    the good autos today do consume
  • 00:16:09
    45 watt per kilometer
  • 00:16:13
    so they have a decent regeneration
  • 00:16:15
    efficiency
  • 00:16:17
    and then the motors etc are
  • 00:16:20
    decent so motor controller
  • 00:16:25
    and any other loss of course this does
  • 00:16:27
    not take into account if you put the
  • 00:16:29
    lights on
  • 00:16:30
    that time you will consume more energy
  • 00:16:32
    that is fine
  • 00:16:33
    this is what you can get and this
  • 00:16:37
    this pure from theory now how do you
  • 00:16:40
    reduce
  • 00:16:40
    this further from if somebody says well
  • 00:16:43
    i want it to reduce from 40
  • 00:16:45
    watt per kilometer well of course if i
  • 00:16:47
    makes a regeneration better i will
  • 00:16:50
    i will improve that i can also do by
  • 00:16:53
    reducing weight
  • 00:16:55
    remember that that is the first thing
  • 00:16:58
    that helps m comes in everywhere m comes
  • 00:17:01
    in rolling resistance in acceleration
  • 00:17:04
    it comes when you travel up the slope
  • 00:17:09
    if i reduce the rolling resistance put
  • 00:17:12
    better tire that will improve
  • 00:17:14
    will see that in the end if i put better
  • 00:17:18
    aerodynamics
  • 00:17:19
    it will reduce the energy required to
  • 00:17:23
    overcome
  • 00:17:24
    the drag that will also improve
  • 00:17:27
    ok and as i pointed out regeneration um
  • 00:17:31
    um so this is something that we have to
  • 00:17:34
    actually do
  • 00:17:35
    so without regeneration you consume as
  • 00:17:38
    much as 50.
  • 00:17:39
    so regeneration is very important now
  • 00:17:41
    remember regeneration is
  • 00:17:43
    combination of battery and motors and
  • 00:17:45
    controller first of all motor
  • 00:17:47
    it will as it turns reverse it has to
  • 00:17:50
    act as a generator and give you the
  • 00:17:53
    [Music]
  • 00:17:54
    electricity but then you have to convert
  • 00:17:58
    that electricity
  • 00:18:00
    back into the voltage which can go into
  • 00:18:02
    the battery if you are not able to put
  • 00:18:04
    it into the battery that is wasted
  • 00:18:08
    so it requires some careful design of
  • 00:18:10
    battery and motor
  • 00:18:12
    combine combined kinetic energy
  • 00:18:18
    so what is regeneration deceleration
  • 00:18:22
    kinetic energy is getting converted to
  • 00:18:23
    electricity
  • 00:18:26
    what about climbing up and down um
  • 00:18:29
    when you climb down you have a
  • 00:18:31
    gravitational energy the potential
  • 00:18:33
    energy
  • 00:18:34
    you are converting back to electricity
  • 00:18:37
    so that is what you will do i think
  • 00:18:40
    getting 40 is quite easy
  • 00:18:43
    and that's what people are getting so e
  • 00:18:45
    auto summary
  • 00:18:47
    will consume between 40 watt hour to 40
  • 00:18:49
    50 wattage per kilometer as i told you
  • 00:18:52
    most of them today actually consume 45
  • 00:18:54
    ah
  • 00:18:55
    remember that 45 consumption is without
  • 00:18:59
    lights on if there is any such thing
  • 00:19:02
    as lights etcetera on its always extra
  • 00:19:05
    its not
  • 00:19:06
    counted ah as a standard thing
  • 00:19:10
    as i told you inefficiency in motor
  • 00:19:11
    control will add up the energy required
  • 00:19:14
    driving at higher speed you do not drive
  • 00:19:17
    as per the drive cycle
  • 00:19:19
    if you drive at higher speed you will
  • 00:19:21
    consume more energy
  • 00:19:23
    if you overload a vehicle you will
  • 00:19:26
    consume more energy
  • 00:19:29
    and that is quite common in india
  • 00:19:33
    if you climb slopes you will
  • 00:19:37
    conver use more energy well range will
  • 00:19:39
    go down
  • 00:19:42
    the key thing is that you are not
  • 00:19:44
    climbing slopes all the time
  • 00:19:47
    of course if the regeneration is good it
  • 00:19:50
    will only marginally impact
  • 00:19:55
    the other thing that is very important
  • 00:19:56
    which will go through
  • 00:19:58
    as we look at the batteries in more
  • 00:20:00
    detail
  • 00:20:01
    the battery starts with certain capacity
  • 00:20:03
    and as you start using its capacity
  • 00:20:06
    keeps coming down coming down coming
  • 00:20:08
    down
  • 00:20:09
    finally it reaches a certain level where
  • 00:20:11
    the energy
  • 00:20:13
    in a battery becomes too small even when
  • 00:20:15
    it is fully charged
  • 00:20:17
    that time you replace the battery so you
  • 00:20:20
    must remember that range that you
  • 00:20:22
    calculate using this
  • 00:20:23
    will come down as the battery becomes
  • 00:20:25
    older
  • 00:20:27
    all this has to be taken into account in
  • 00:20:29
    a vehicle design
  • 00:20:31
    let me re do the same exercise
  • 00:20:35
    for eric shop now eriksha is a new thing
  • 00:20:39
    in india
  • 00:20:40
    though we know that the upper limit is
  • 00:20:42
    25 kilometer per hour
  • 00:20:44
    this is a requirement you do not get a
  • 00:20:46
    license if it is above 25 kilometer per
  • 00:20:48
    hour
  • 00:20:49
    in fact you do not need a driving
  • 00:20:51
    license to
  • 00:20:52
    drive a reaction and that's a good
  • 00:20:55
    regulation
  • 00:20:56
    saying that well it has to be under 25
  • 00:20:58
    kilometer per hour
  • 00:21:00
    just slow moving but a very important
  • 00:21:03
    ah part of uh life in india
  • 00:21:06
    it has actually replaced all rickshaws
  • 00:21:09
    and therefore all slow
  • 00:21:11
    moving vehicles traffic
  • 00:21:14
    is so slow moving traffic so in fact
  • 00:21:17
    ericssons are not allowed on the
  • 00:21:19
    highways ericssons are not allowed in
  • 00:21:21
    the bridges
  • 00:21:22
    it does not have the sufficient torque
  • 00:21:25
    for it to climb
  • 00:21:27
    [Music]
  • 00:21:29
    but with this restriction it works very
  • 00:21:31
    well remember that old
  • 00:21:33
    hand pulled rickshaw and cycle rickshaw
  • 00:21:36
    that used to be used
  • 00:21:38
    old person trying to cycle where
  • 00:21:41
    some two three heavy people have sat
  • 00:21:42
    down all this
  • 00:21:45
    to some extent has gone because now
  • 00:21:48
    with the motor driving it becomes easier
  • 00:21:52
    in some cases iriksa is a big boon of
  • 00:21:55
    course a slow moving so it can block the
  • 00:21:57
    traffic so that those are concerns
  • 00:21:59
    but there is a drive cycle defined this
  • 00:22:02
    is not a
  • 00:22:03
    strictly a standard it is some of us had
  • 00:22:06
    got together all with all the ericsson
  • 00:22:08
    manufacturers
  • 00:22:09
    and figured out what kind of drive do
  • 00:22:11
    they actually do
  • 00:22:12
    and you find that either they drive they
  • 00:22:15
    first
  • 00:22:15
    they will go to a certain speed and keep
  • 00:22:18
    on going down
  • 00:22:19
    then they will go to another speed and
  • 00:22:20
    keep on drawing down on the average we
  • 00:22:22
    found that with when measuring
  • 00:22:24
    that this what they are doing and we
  • 00:22:26
    actually define this
  • 00:22:28
    and there is a frequent stopping and
  • 00:22:31
    increasing the speed
  • 00:22:32
    and therefore there is a increase in
  • 00:22:34
    speed and going down
  • 00:22:35
    now remember if there is regeneration of
  • 00:22:37
    hundred percent this will not consume
  • 00:22:39
    much energy but otherwise it will
  • 00:22:40
    consume energy
  • 00:22:41
    and will define that again every second
  • 00:22:43
    what happens
  • 00:22:45
    every second or for five seconds or nine
  • 00:22:48
    seconds
  • 00:22:48
    five to nine second speed will be this
  • 00:22:51
    we define that
  • 00:22:53
    and then from 9 to 18 second speed will
  • 00:22:55
    be this
  • 00:22:58
    so you can you can compute the
  • 00:22:59
    acceleration
  • 00:23:02
    okay you can compute the acceleration
  • 00:23:04
    put the
  • 00:23:05
    input to the spreadsheet every second
  • 00:23:08
    what the velocity will be
  • 00:23:10
    every half a second what the velocity
  • 00:23:12
    will be compute the acceleration
  • 00:23:14
    and you take the specification of
  • 00:23:16
    ericsson that is very important
  • 00:23:18
    this is the input to the spreadsheet the
  • 00:23:20
    mass 680 kg
  • 00:23:22
    g the rolling resistance drag density of
  • 00:23:26
    air projected area the drive cycle
  • 00:23:30
    wheel radius and regeneration the
  • 00:23:31
    efficiency so you take all of that
  • 00:23:34
    and you find that this is
  • 00:23:37
    what the drive cycle gives you it is a
  • 00:23:39
    727 meter
  • 00:23:41
    this plots the incremental distance that
  • 00:23:43
    you travel this in
  • 00:23:44
    plots the velocity and 727 meter drive
  • 00:23:48
    cycle
  • 00:23:49
    now you compute the
  • 00:23:52
    force traction force power
  • 00:23:56
    torque remember so far we have not been
  • 00:23:59
    using torque because we went into energy
  • 00:24:01
    and energy efficiency torque will play a
  • 00:24:03
    very important role
  • 00:24:04
    later on when we design the motor as
  • 00:24:07
    well as the battery
  • 00:24:11
    it will play a very important role and
  • 00:24:13
    but we know what the torque will be
  • 00:24:15
    and we find again that if i
  • 00:24:19
    take the thing with 100
  • 00:24:23
    with approximately
  • 00:24:26
    [Music]
  • 00:24:28
    it takes 24 point
  • 00:24:31
    uh 24.53 watt hour
  • 00:24:38
    this actually shows me a little higher
  • 00:24:41
    ah
  • 00:24:43
    at 727 meter this shows me more like 28
  • 00:24:46
    29
  • 00:24:47
    watt hour this actually shows me 20 so
  • 00:24:50
    this is probably a different
  • 00:24:51
    regeneration efficiency with 100 percent
  • 00:24:54
    regeneration efficiency
  • 00:24:56
    it should be 27 watt hour ah
  • 00:25:00
    27 watts per kilometer and again the
  • 00:25:03
    number here shows different
  • 00:25:05
    i'll check this out why it is so but i
  • 00:25:08
    am able to i know that travel 727 meters
  • 00:25:11
    so i am able to find out the energy
  • 00:25:12
    efficiency energy efficiency
  • 00:25:14
    is 27 with hundred percent regeneration
  • 00:25:18
    efficiency
  • 00:25:19
    33 with 50 percent regeneration
  • 00:25:22
    efficiency
  • 00:25:23
    and without regeneration it is 40. this
  • 00:25:26
    is what a e rickshaw consumes
  • 00:25:29
    remember its a slow moving vehicle
  • 00:25:33
    so in some sense it is different its a
  • 00:25:35
    slow moving vehicle
  • 00:25:36
    and thats what happens
  • 00:25:39
    any questions so i have done it for two
  • 00:25:41
    wheelers i have done it for e-rickshaw
  • 00:25:44
    i have done it for auto let's do it for
  • 00:25:47
    the vehicle that i drive
  • 00:25:51
    a small sedan so iriksha summary even
  • 00:25:54
    with higher weight
  • 00:25:55
    the energy efficiency is below 35 watt
  • 00:25:57
    hour per
  • 00:25:58
    kilometer with 50 regeneration in
  • 00:26:01
    efficiency now what does it mean if i
  • 00:26:03
    take a 2.5 kilo
  • 00:26:05
    watt hour battery and i am consuming
  • 00:26:08
    only 35 watt
  • 00:26:10
    per kilometer it can easily give me 50
  • 00:26:13
    ah 50 kilometer range even taking into
  • 00:26:16
    account that only 85 percent of the
  • 00:26:17
    battery is usable
  • 00:26:19
    at any time of course you remember that
  • 00:26:22
    there is reduction in battery capacity
  • 00:26:25
    over time so your 50 kilometer range
  • 00:26:27
    will start slowly coming down
  • 00:26:30
    overloading and over speeding will
  • 00:26:33
    hurt always
  • 00:26:39
    you
タグ
  • dynamique des véhicules
  • résistance aérodynamique
  • cycles de conduite
  • régénération d'énergie
  • efficacité énergétique
  • calcul de puissance
  • nécessite énergétique
  • types de véhicules
  • méthodes d'optimisation
  • analyse de performance