The trend towards increased integration of electrical and mechanical functions in today’s automobiles has led to the development of “reverse alternators” or integrated starter generators (ISG)/integrated starter alternators (ISA).
The ISG/ISA combines starter and alternator functions into one compact system, allowing for start-stop strategies, brake regeneration, and power assist/boost. Starter-alternators makes it feasible to significantly increase the power generation capability of the engine and require specialized power systems.
The starter-alternator power stage employs a controlled three-phase MOSFET bridge that can be used to rectify the generated AC current as well as generate from a DC bus, three-phase current in an inverter mode to convert the generator to a starter motor. The multifunction power stage is controlled by a controller board, which sets the motor and generator modes to drive the power stage accordingly.
Design can address both power and control solutions to meet a customers’ 14V or 42V system requirements. KSR closely integrate the MOSFETs with the drivers for optimum performance. The controller board includes multiple diagnostic and fail-safe functions. The circuit is optimized for high efficiency, with a low inductance pin-out.
Packaging is optimized for low thermal resistance, providing enhanced reliability in high temperature environment and compact footprint. Special interconnection technology is used for high current handling. A 42V to 14V DC-DC converter can also be integrated into the system if required.
KSR control hardware & software features include:
• Demonstrated designs up to 20kW
• Up to 600A, with peak currents up to 1.7kA
• Over-current and over-temperature protection
• High efficiency
• Minimal stray inductance
• Phase and/or bus current sensing
• Up to 1.5kW DC-DC converter
In addition to cabin fan control modules, electric steering control units, steering power modules, alternator voltage regulators and engine fan control modules, KSR is an industry leader in the design, engineering and manufacture of pedals, assemblies and throttle controls, and a wide variety of automotive sensors.