“Vehicle electrification will be an important growth area for the automotive industry until zero emissions are achieved. To achieve this, automotive systems will require more semiconductors as well as more demanding computing and software.
Vehicle electrification will be an important growth area for the automotive industry until zero emissions are achieved. To achieve this, automotive systems will require more semiconductors as well as more demanding computing and software.
It will be very interesting to see the meaning behind this from an economic point of view. IHS Market and Strategy Analysis estimates that the added value of semiconductors for electric vehicles (EVs) is $200 for mid-size hybrid electric vehicles (HEVs) and about $450 for battery electric vehicles (BEVs).
But the internal combustion engine (ICE) isn’t going away anytime soon. Electrification of ICE powertrains and semiconductor usage will continue to grow, and NXP Semiconductors will continue to support these engines. As electric vehicles increase, the number of internal combustion engines will decrease. What is driving the growth of electric vehicles? There are multiple factors, but the first is the need for cleaner emissions, and this is where government legislation and incentives come into play. Battery costs are also falling, making electric vehicles more affordable. As battery performance improves, so does the range of electric vehicles. Finally, substantial investment by original equipment manufacturers (OEMs) in EV technology will increase the efficiency of inverter systems.
Evaluating High Voltage Power Inverters
A key subsystem of electric vehicles is the high-voltage (HV) power inverter. A vehicle can have multiple high-voltage power inverters, but on-board charging (OBC), DC-DC battery boost circuits, and traction motor inverters are the most common. Several other motors in a car may need their own inverters, one example of which is the air conditioner compressor pump.
High-voltage traction inverters are a research focus for NXP. It converts the DC power of the high-voltage battery into a polyphase AC voltage to drive the traction motor, which drives the vehicle forward. High-voltage traction inverters have particularly high requirements for safety and high-efficiency operation when the typical voltage exceeds 300V. For EV owners, only one percent of the improvement will translate into longer range.
Taking into account the needs of functional safety, functional safety standards need to be developed. They are graded according to the severity of the harm to the human body when the system fails. For automotive systems, this is the Automotive Safety Integrity Level (ASIL) from A to D. A number of different elements are considered in functional safety standards, such as hardware, software and system development processes. Furthermore, automotive system developers such as Tier 1 suppliers and OEMs need to properly document these processes, which needs to be supported by functional safety certified components.
Since the traction inverter is an extremely critical safety system, it must be certified to ASIL-C/ASIL-D systems. An example of a failure that a traction inverter can cause is an unexpected acceleration or stop. This includes loss of power while driving, unexpected braking, and excessive braking. It is easy to understand the criticality of the systems by imagining what this would be like when driving on the highway, and therefore these systems need to comply with functional safety specifications.
NXP offers functional safety compliant components to control high voltage traction inverters. NXP provides MPC5775E MCU, FS6500 system basis chip to power the controller, TJA1051 redundant CAN bus interface for communication, and GD3100 advanced gate driver with integrated high voltage isolation function to meet the stringent requirements of the system. These components can be used with insulated gate bipolar transistor (IGBT) or silicon carbide (SiC) modules from partners, all with high-efficiency reference designs.