In the past two years, passive component manufacturers are actively expanding the production capacity of passive components in high-end application fields, hoping to occupy more voice and market share in incremental markets such as 5G, automotive, photovoltaic, intelligent consumer terminals, and Industry 4.0. As the cornerstone of the electronics industry, passive components not only play a silent role in the circuit of traditional application fields, but also assume important responsibilities in emerging fields such as 5G, new energy vehicles, and photovoltaic. The automotive field is undoubtedly the application direction of passive components that has attracted much attention now.
Resistance components in automotive electric drive systems
The electric drive system of new energy vehicles has undergone earth-shaking changes compared with the system of traditional internal combustion engines. At this stage, the high integration, high efficiency and 800V high voltage of electric drive systems are clear development trends. The upgrade of the electric drive system also puts forward new requirements for various kinds of devices used in it. The motor controller, as the control unit that controls the motor driving the whole vehicle, converts the direct current delivered by the battery pack through the high voltage box into alternating current to supply the drive motor, which is the core component of the electric drive system. In the process of controller operation, the main controller will control the inverter IGBT or SiC module by collecting and analyzing the acceleration, braking and other sensor information output PWM signal, so as to achieve the purpose of controlling the motor work. At the same time, the main control also collects the current, voltage, temperature and temperature of the power device when the motor is working to protect the system from overcurrent, overvoltage and overheating.
This involves the application of many passive components. In the voltage division detection circuit, the application of resistance is very basic and very critical. First of all, the precision of the resistance applied in it must be higher (relative to the current limiting resistance), the precision of the partial voltage resistance will affect the estimate of the real voltage, in the electric drive system, the voltage is very high, any deviation may bring hidden dangers. In addition, high reliability and strong pulse resistance are also essential. If the working voltage of the resistor can be high, it is also helpful to reduce the amount of detection resistance, and it is also in line with the current design trend of highly integrated and high voltage electric drive systems. At the same time, the application of discharge resistance in the electric drive system is also more and more, and has become the mainstream solution of the electric drive system, which can bring high safety while not making the motor torque jitter larger.
New energy vehicle capacitor application
There are also many capacitor applications in the car, and the filtering, absorption and resonance of the capacitor are applied everywhere on the vehicle. From the perspective of the vehicle, the capacitor of the car not only enhances the performance of the car, but also helps to ensure the service life of the car. At present, the most popular MLCC and DC film capacitors are all the capacitors used in new energy vehicles. In the OBC alone, the amount of DC thin film capacitors is already a lot, from EMI filter capacitors to PFC capacitors, to DC-Link capacitors, to LLC resonant phase capacitors, and finally the output capacitors. These thin film capacitors build a safe and stable OBC module by virtue of their strong overvoltage resistance and high frequency performance.
Needless to say, in the new energy vehicle C.A.S.E. trend, high-quality MLCC is a very popular passive device. The corresponding technical threshold is also very high, even if it is the same size and capacity as the non-vehicle regulations, the vehicle MLCC also needs more advanced technology and strict production system to ensure that it provides more than 20 years of service life. Vehicle high reliability MLCC has large capacity and low ESL, including several types of soft terminal capacitor, bracket capacitor and three-terminal capacitor. Applications can be seen from ADAS to various control systems, from positioning modules to battery management modules.
In addition to resistors and capacitors, the application of inductors in new energy vehicles also continues to promote the continuous breakthrough of inductors in the process innovation ability and magnetic powder formula to seek better characteristics. For example, power inductors, which improve the link characteristics of any BOOST circuit and BUCK circuit in automotive electronics, are indispensable. New energy vehicles require circuits to provide more stable power over a wider temperature range, so the power inductor must be innovated in magnetic leakage and saturation characteristics.
The integrated molding coverage of inductors is also very high, the future will have more power inductors using integrated molding technology, automotive electronics demand also to a certain extent to promote the improvement of integrated molding coverage, integrated molding can maintain excellent temperature rise current and saturation current characteristics under high frequency and high temperature environment. In order to meet the development of new energy vehicles, passive components are constantly improving the process and exploring materials to seek breakthroughs, and achieve higher performance under the premise of sufficient reliability.