Reference platform supports EV power systems
MUNICH — As auto manufacturers pursue their quest for extended range and — ultimately — pure electric vehicles, chipmakers are following suit with the controllers and platforms needed to address the higher voltage battery systems. To that end, NXP Semiconductors is rolling out a new reference platform for EV traction motor inverters and two new battery cell controllers for battery monitoring and management.
The road to vehicle electrification requires more than just high-voltage power switches. What NXP is providing is is the ability to build a system that is inherently functionally safe, making sure the motor is doing exactly what it is supposed to be doing, according to the company.
For the power inverter platform, NXP has partnered with VEPCO Technologies Inc. to engineer an ASIL-D-capable, high-voltage power control reference platform and inverter prototype. The platform controls a Fuji Electric 800V silicon IGBT power module with integrated current and temperature sensing for driving 100 kW 3-phase motors.
Customers can develop motor inverters based on the reference design platform with NXP’s system control components and functional safety software while VEPCO Technologies provides the contract system engineering services for application and performance specific development on the platform, NXP said.
“VEPCO focus on the motor, we focus on the electronics," said Thomas Lentsch, director of strategy and business development for NXP’s advanced automotive analog products, in an interview with EE Times. "We’re not just putting components on a PCB, but also the documentation and software, which is an important factor.”
Lentsch said the further you want to drive, the more versatility needed, and voltages need to be high. Hence traction motor inverters convert DC battery voltage to multi-phase alternating current to drive the traction motors of electric and hybrid vehicles at the speed and acceleration demanded by the driver.
Output and power density efficiency is particularly critical with battery voltages of more than 300 V,, and output power requirements ranging from 80 kW to 200+ kW. In addition, complex system control is required to monitor the motor’s state, sense the driving currents and reliably calculate and apply the desired torque energy.
The company says its power inverter reference platform provides an efficient system bill-of-materials for both inverter control and drive operations and functional safety assurance. The platform, for which prototypes will be available this quarter, features the new GD3100 isolated high-voltage gate driver IC that targets ISO 26262 ASIL D compliancy, the MPC5775E microcontroller and FS65xx power management safety system basis chip, NXP said.
The GD3100 is a single-channel gate driver for IGBTs, with integrated galvanic isolation and low on-resistance drive transistors to provide high charging and discharging current, low dynamic saturation voltage and rail-to-rail gate voltage control. It features IGBT gate control redundancy and on/off state validation, IGBT current and temperature monitoring, analog and logic BIST (built-in self-test), and low and high voltage fail safe inputs.
The MPC5775E microcontroller comes with integrated motor control capabilities and a software resolver implementation. Running PMSM (permanent magnet synchronous motors) sensorless field-oriented control uses less than 10% of its computing capabilities, leaving maximum bandwidth for all the safety features and complex driving strategies required for EV and hybrid systems, according to NXP.
With its flexible open system enablement, the platform also provides tools for customers to implement unique value-add energy management intellectual property and achieving their required levels of functional safety.
>> Continue reading page two of this article on our sister site, EE Times: "NXP Rolls EV Inverter Platform, Battery Controllers."