In recent years, advances in technology, as well as ever evolving tastes in style, have led to substantial changes in the design of automobiles. One of the changes involves the power usage and complexity of the various electrical systems within automobiles, particularly alternative fuel vehicles, such as hybrid, electric, and fuel cell vehicles.
Many of the electrical components, including the electric motors used in such vehicles, receive electrical power from alternating current (AC) power supplies. However, the power sources (e.g., batteries) used in such applications provide direct current (DC) power. Thus, devices known as “power inverters” are used to convert the DC power to AC power. Such power inverters often utilize several switches, or transistors, operated at various intervals to convert the DC power to AC power.
Typically, the switches of the inverter are operated by using pulse-width modulation (PWM) techniques to control the amount of current and/or voltage provided to the electric motor. Often, a microprocessor generates PWM signals for the switches in the inverter, and provides the PWM signals to a gate driver, which turns the switches on and off. The microprocessor and gate driver often reside on separate circuit card assemblies, and interface via one or more buffers, amplifiers, and other discrete components.
During operation, it is often possible to improve the efficiency of the electric motor and/or the inverter by varying the switching frequency of the PWM signals or the manner in which they are generated. However, the additional tasks and computations required to dynamically adjust the PWM signals using software can increase processing overhead and thereby reduce the throughput of the microprocessor and add latency to the system. Current systems are challenged to provide dynamic real-time operation of the electric motor, and are thus, limited in terms of efficiency.