Thursday, April 30, 2009

2 mode power train :Speed to time graph and modes.

2 mode powertrain, The  previous post shows mild hybrid and diagram . It gives a clear idea on differnce on mild hybrid and 2 mode hybrids (click on the pic to see it in detail )

The Two-Mode hybrid system maximizes city and highway fuel economy by integrating two electric continuously variable modes with four fixed mechanical gear ratios. The system consists of twin, active-cooled electric motors integrated into the automatic transmission. Energy to power the motors comes from a 300V nickel-metal hydride battery pack, which consists of nickel metal hydride modules and is packaged behind the second-row seat below the cargo floor.

In the first mode, at lower speed and lighter loads the 2-Mode Hybrid operates in one of three ways depending on conditions and battery charge level: all-electric power, internal combustion engine power or a combination of the two. All reverse operation is driven solely by the electric motors.

The second mode is used primarily to optimize fuel economy at highway speeds. It provides electric assist in addition to combustion engine power when conditions demand it, such as trailer towing and climbing steep grades, and to allow the engine to run at its most efficient point under less-demanding conditions.

No engine speed changes are necessary for the mode shift to occur. The result is exceptionally smooth, seamless acceleration and responsiveness. At all times, the Hybrid Optimizing System (HOS) collects torque-based data, deciphers it, then determines the most fuel-efficient means of propelling the 2-Mode Hybrid.

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Greenlings: What is a mild hybrid?

People like to categorize the world. It helps our brains figure stuff out, because we can only manage so much information. Lumping things into bins helps get information down to a manageable level. Unfortunately, most things don't readily fall into discrete categories. Hybrid drive technology is one of them, but we'll try anyway. On the continuum that is hybrid technology, we typically break things down into strong, mild and micro-hybrids. Strong hybrids include systems like Toyota's hybrid synergy drive, Ford's hybrid system and General Motors two-mode system. Micro-hybrids are really nothing more than automatic start stop systems.  Somewhere in between those groups lies the mild hybrid. The basic premise of the mild hybrid is the same as the strong hybrid. An electric motor/generator operate in parallel with the internal combustion engine to provide additional drive torque as well as regenerative braking. The primary difference lies in the power and energy capacity of the electrical side of the system. Continue reading about mild hybrids after the jump. 

Why would an automaker create a mild hybrid system? Mainly to get some of the benefits of a hybrid system at a significantly lower cost and weight. Mild hybrids typically have a much smaller battery than a strong hybrid and a smaller, weaker motor/generator. The first manufacturer to build a system that fits into the mild category is generally considered to be Honda with it's Integrated Motor Assist (IMA) system as used in the Insight and Civic. 

Since the Insight debuted in 1999, General Motors has released two different mild hybrid systems, one that was briefly offered in the Silverado hybrid in 2005-6 and the more recent belt-alternator-starter (BAS) system offered on several models. Mercedes-Benz and BMW have also co-developed a system of their own that will debut this summer on the S400 BlueHybrid and then on the new 7-series.  The GM system uses what is essentially a beefed up alternator and modified belt drive system to provide some additional drive torque to the engine as well as re-start it. Other systems, such as those from Honda and Mercedes, use a disk-shaped motor-generator sandwiched between the engine and transmission to provide the same functionality. The motor also takes the place of the torque converter in the transmission. 

During deceleration the mild hybrid system can also provide some regenerative braking capability. Because the battery pack is generally smaller than what you find on a strong hybrid, the ability to store energy to drive the vehicle is limited. However, the Mercedes-BMW mild hybrid is using the electrical power in a different way. The energy stored in the battery is being used to drive vehicle electrical systems such as audio, windows, HVAC and others. By using recaptured kinetic energy, the load on the alternator is reduced, cutting parasitic losses.  The Mercedes mild hybrid system will be the first mainstream hybrid to use a lithium ion battery. The Continental-supplied battery is mounted under-hood and is the same size as the traditional lead-acid starter battery, which is replaced by the lithium unit. In 2010, GM plans to launch a second-generation version of its mild hybrid. The new version increases the motor power from 5 to 15 kW and the current nickel metal hydride battery is replaced by a higher capacity, lighter lithium ion unit.  While a mild hybrid system can't drive the vehicle on electricity alone, it still provides benefits. Like direct injection and turbocharging, it allows the automaker to downsize the base engine while maintaining the same performance level. The combination of the reduced peak output of the engine and eliminating engine idle can contribute fuel consumption savings of up to 15 percent in urban driving and 8-10 percent overall. While not as significant as a strong hybrid, these benefits come at a much lower cost in mild hybrid form.

© yankandpaste®

Wednesday, April 1, 2009

Why Indians Don't Envy Israel?

And Why Tharoor's Brief for Israel Is Not Convincing.

Perhaps, it was a well-intended article, meant to instill sense to the senseless people who have been clamoring for an all-out war with Pakistan to take out the terrorist camps and to put an end to the terrorist strikes that have become so commonplace lately. I said perhaps. Perhaps because I still respect the author for his writings that used to uphold the plurality and secularism of India; for all that he has written against the growing clout of the majority fundamentalism in India. But then, I wrote perhaps. Perhaps because the Haaretz article does not read like one from the celebrated author and champion of Indian plurality, who once wrote if America is the melting pot of cultures, India is more like a thali meal, where each dish has its own character and taste and yet complements each other in making the meal a satisfying repast.

India's Israel Envy, read the title, which the author later attributed to the Israeli newspaper editors. But, for all that one understands from the piece, the title just sums up what Mr. Tharoor says in so many words-a case of sour grapes.

Look at the words used in the first paragraph. "As Israeli planes and tanks were exacting a heavy toll on Gaza, India's leaders and strategic thinkers were watching with an unusual degree of interest - and some empathy." Unusual degree of interest and some empathy from India's leaders and strategic thinkers, it says. For all that we know, our country and most of our leaders till very recently-that is until the BJP Government opened diplomatic channels with Israel-had their sympathies with the people of Palestine, for their just cause, for all their sufferings. And even now, the right-thinking people of this country who haven't lost sense of justice have their sympathies with the cause of Palestine. So, from where does this interest-isn't it such a positive word? Like watching a cricket match? I thought we watched terrorist attacks - government-sponsored and private - with anxiety, and not interest-come from? And empathy? Well, only Mr. Tharoor knows when did our sympathies for Palestine people transform into empathy for Israel.

Mr. Tharoor's admiration for the Israeli action becomes clear as he goes on eulogizing Israeli determination in dealing with the Hamas. As if to show that he is not the only Indian charmed by the Israeli iron fist, he writes that the Indians have been nodding in appreciation and asking "why can't we do the same?"

He continues:
"For many Indians, the temptation to identify with Israel was strengthened by the terrorists' seizure of the Chabad House, and the painful awareness that India and Israel share many of the same enemies. India, with its 150 million Muslims, has long been a staunch supporter of the Palestinian cause, and remains strongly committed to an independent Palestinian state. But the Mumbai attacks confirmed what has become apparent in recent years: The forces of global Islamist terror have added Indians to their target list of reviled "Jews and crusaders."
Just as Israel has frequently been attacked by rockets fired from across its border, India has suffered repeated assaults by killers trained, equipped, financed and directed by elements based next door, in Pakistan. When President George W. Bush's press secretary equated members of Hamas with the Mumbai killers, her comments were widely circulated in India."

After painfully building his argument that there are many parallels between India and Israel and cleverly putting India with the Western forces in the Us versus Them global war on terror, he declares: "Yet there the parallels end". And that line did make me hope that he was coming to the facts there. I thought he would tell us why we shouldn't put the terrorism in India and Israel in the same bracket. I thought he would tell us why people should stop eulogizing the Israeli determination and understand that what Israel is carrying out on Palestine and its people is another brand of terrorism-a state-sponsored, home-grown brand, and that Palestinians were forced to doing what they are doing now by decades of Israeli (with the active support and encouragement of the US) atrocities against the people of Palestine, that UN and the people of this world have been made mute-spectators to one of the worst human-right tragedies of our times.

Instead, he goes on to build a rather baffling argument:
"Israel is a small country living in a permanent state of siege, highly security-conscious and surrounded by forces hostile to it; India is a giant country whose borders are notoriously permeable, an open society known for its lax and easygoing ways."
The problem is with our country and our people, he says. He forgets that we are fighting different issues; except for the Islamic prefix (well, then, who said Gujarat pogrom was not a terrorist activity? What about Malegaon? Babri Masjid?), there isn't much in common. I wish I were a little too naïve to think that Sashi Tharoor doesn't know these.

What is more baffling is his parroting the Sangh Parivar line of India being a soft state. He forgets the realities. He forgets what India has been doing in fighting terrorism. He forgets that we cannot afford to have a tough-state label at the cost of basic human rights. And, most surprisingly, he doesn't talk about the causes of terrorism at all; he talks only about the symptoms and addressing the symptoms. Baffling, isn't it? A friend suggested that he might have lost his senses the moment he joined Indian politics; not that I think all our politicians are senseless, but I liked that observation for want of anything better to explain Tharoor's rather nonsensical article.

After explaining in length about why we "cannot" do what Israel is doing; he concludes:
"Yet, when Indians watch Israel take the fight to the enemy, killing those who launched rockets against it and dismantling many of the sites from which the rockets flew, some cannot resist wishing that they could do something similar in Pakistan. India understands, though, that the collateral damage would be too high, the price in civilian lives unacceptable, and the risks of the conflict spiraling out of control too acute to contemplate such an option. So Indians place their trust in international diplomacy and watch, with ill-disguised wistfulness, as Israel does what they could never permit themselves to do."
Again, look at the words; whoever said words do matter was so right I realize as I watch, disappointed, another icon, created by powerful words, being demolished by his own words. Take the fight to the enemy, he wrote, betraying his sympathies for Israeli action. Suddenly, he sounds so pedestrian, pretends like someone who has forgotten his history lessons, like one of those next-door knicker-wallahs who make sweeping statements like every madrassas in this country has terrorists in them and should be taken out along with the terrorist camps across the border. Yeah, those knicker-wallahs have long been talking about taking a few leaves out of the Israel's anti-terrorist operations.

Mr. Tharoor goes on to say that Indians watch Israel doing what they could never permit themselves to do, with ill-disguised wistfulness! And the reasons why we CANNOT do to Pakistan what Israel does to Palestine, the nuclear warheads Pakistan has; otherwise, we could have done what the US has done in Afghanistan and Iraq, what Israel continues to do with Palestine. As I finished reading the piece, I couldn't help wondering whether he has really lost his senses. Perhaps.

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