Global Network of Innovation Integrated Starter-Generator
Powerful Partnership
In the future, power supply units in passenger cars will integrate the starter and generator into a single unit. The resulting solution makes more power available to the axles, recovers braking energy and saves fuel. In a unique example of global cooperation, the software for the integrated starter-generator is being written by developers in Germany and India.
Exemplary teamwork between Germany and India. While engineers in Würzburg test a starter-generator, their colleagues in Bangalore (below) develop software modules
Udo Frinzel is about to lock up his office when the telephone rings. It's an urgent call for help from fellow systems developers in Würzburg, Germany. "There's a fault somewhere in the adapter. Can you help us out?" Frinzel can. A software developer at Siemens VDO Automotive in Regensburg, Frinzel promptly sends an e-mail to Bangalore, India. The next day, because of the time zone difference, the computer specialists at SISL (Siemens Information Systems Ltd.) in this South Asian high-tech metropolis are at their desks hours before their German counterparts, and have already solved the problem by the time Frinzel has his morning coffee. "That has happened several times," reports Frinzel, looking amused by the idea.
Frinzel is in charge of a project that will revolutionize electronics in the automobile: the Integrated Starter-Generator (ISG), a power converter that will replace the starter and the generator in tomorrow's cars. Installed between the engine and the transmission, the ISG converts mechanical power into electrical power and vice versa. As an electric motor, it starts up the combustion engine almost noiselessly and much faster than any conventional starter. In its role as a generator, it produces electric power for the lights, air conditioning system, radio and all other energy-consuming components in the carand with greater efficiency than its conventional predecessors. Any excess power is used to charge the battery. And during braking, kinetic energy is converted into electrical energy and stored. When needed, the ISG can then apply more power to the axles or propel the vehicle electrically over short distancesfor instance, in stop-and-go traffic.
At a stoplight, the combustion engine is automatically turned off as long as the driver keeps his foot on the brake pedal. When the brake is released, the starter-generator accelerates the crankshaft to idle speed within fractions of a second, and the engine control unit resumes fuel injection and ignition. The ISG provides a car with up to 15 kW more power and cuts fuel consumption by up to 15 %. The functions of the ISG, combustion engine, transmission and battery are coordinated by Integrated Powertrain Management software. To fully exploit all of the new system's advantages, the various components have to be able to communicate extremely quickly and efficiently. That calls for intelligent software development.
The development of the ISG is a perfect example of global cooperation at Siemens. Experts in Regensburg and Bangalore are the key players in this project. The initial customer is a European automaker supported by Siemens VDO engineers in Toulouse, France. Additional support is available from programmers in Schwalbach (near Wiesbaden, Germany), Timisoara (Romania), Ichon (Korea), and Auburn Hills near Detroit (U.S.A.). The ISG is being built in Würzburg, while its related electronics are being built in Regensburg (Germany) and Frenstadt (Czech Republic). Every week, the software hubs in Regensburg and Bangalore hold a conference call. Each year, two Indian developers go to Germany, where they work with German auto engineers to further improve collaboration. Labhchand-Govind Lakhotia has already completed the larger part of his stay. Even the cold German winter hasn't discouraged him. "I was absolutely intent on seeing the results of our programming work in practice," says Lakhotia.
New geometry under the hood: In the future, the starter and the generator will be combined in the ISG, which is located between the engine and the transmission. The illustration (right) shows a three-dimensional notebook screenshot of the ISG
Frinzel commends Siemens' Indian developers. "They are extremely flexible and adaptable," he says. The SISL site is located in Keonics Electronics City, 40 minutes by car from downtown Bangalore, a metropolis of five million people. In the ten-story Siemens buildingthe tallest in this large industrial park250 specialists write software mainly for medical imaging systems. In addition, they work on projects for the automotive industry, mobile communications, rail systems and process automation. At Siemens Communications Software (SCS) in downtown Bangalore, another 600 professionals (with an average age of 26) are principally developing software for automatic telephone switching systems and mobile communications used by numerous telephone companies all over the world.
When employees at Siemens VDO began working with their colleagues at SISL nearly six years ago, the main reason for employing Indian computer scientists was cost. Now the outstanding quality of their work is a principal factor. "It's not just that we're inexpensive; we also provide top quality," says SISL Quality Manager Rakesh Kumar Singh. And he points out that SISL is the first Siemens company that has earned the fifth levelthe highestof the CMM international quality standard for software companies. It's something that only 50 companies worldwide have achieved besides SISL.
Tests at the customer site have now been successfully completed and the quality of the ISG software has become evident. The software description fills an entire A4 format binder. A single developer would have required 30 years to complete the 370 or so modules. These modules keep the engine from overheating, regulate the voltage and measure engine speed. Some routines in the chips are repeated once every ten millisecondsfor instance for the module that diagnoses interruptions in the power supply. Modularization has several advantages. It allows the components to be smaller and easier to understand, and to be designed to be as compatible as possible, so the system as a whole can be rapidly adapted to new requirements.
Frinzel has no doubt that the ISG will be successful. In addition to Siemens, Bosch, ZF Sachs and other companies are also working on such a product. "Siemens is in the best position, and will be among the first to begin volume production late in 2002," Frinzel notes. Other projects are already in progress. Siemens VDO is also taking aim at the enormous U.S. market. "Once we have customers in America, we can really say that software development at Siemens follows the sun around the earth," Frinzel says.
Norbert Aschenbrenner