The development trend of power semiconductor modules

(1) Modularization of power electronic semiconductors: Modularization, according to the original definition, is to connect two or more power semiconductor chips according to a certain circuit structure, using RTV, elastic silicone gel, epoxy resin and other protective materials , Sealed in an insulated shell, and insulated from the thermally conductive bottom plate. Since the module principle was introduced into the field of power electronics technology, a variety of power semiconductor modules with interconnected internal circuits, such as bidirectional thyristors, power MOSFETs, and insulated gate bipolar thyristors (IGBT), have been developed and produced, making the module technology possible Faster development. With the successful development of modern semiconductor devices based on the MOS structure, people combined the device chip with control circuits, drive circuits, overvoltage, overcurrent, overheat and undervoltage protection circuits, and self-diagnostic circuits, and sealed them in the same insulating housing. It is called an intelligent power semiconductor module, or IPM. In order to improve the reliability of the entire system, to adapt to the development of power electronics technology towards high frequency, miniaturization and modularization. On the basis of IPM, some inverter functions are added, so that all the components of the inverter circuit (IC) are packaged in a module in the form of a chip, which becomes a user-specific power module (ASPM). Such a module is more conducive to High frequency. In order to integrate integrated circuit ICs with logic levels of several volts and several milliamps with power semiconductor devices of several hundred volts and several thousand volts to meet the development of electric power industry, people adopt hybrid packaging methods to manufacture Integrated Power Electronic Module (IPEM) for various occasions.

(2)Intelligent Thyristor Module: ITPM (Intelligent Thyristor Power Mudule) is made by encapsulating the main circuit of the thyristor, the phase-shifting trigger system, over-current, over-voltage protection, sensors, etc., in a plastic shell. The relevant circuit becomes a whole. The thyristor is a current-controlled power semiconductor device and requires a large pulse trigger power to drive the thyristor. This module is difficult to make.

(3) IGBT smart module: In the 1980s, insulated gate bipolar transistor IGBT devices were successfully developed. Because IGBT devices have the advantages of voltage-type driving, low driving power, high switching speed, reduced saturation voltage, and high voltage and high current resistance, they can be driven and controlled by IC, and then developed into integrated IGBTA chips. , Fast diode chip, control and drive circuit, over-voltage, over-current, over-heat and under-voltage protection circuit, box position circuit and self-diagnostic circuit are packaged in the same insulating shell, with intelligent IGBT module (IPM). It creates a device foundation for the high frequency, miniaturization, high reliability and high performance of power electronic inverters.

(4) Communication power supply module: The current development trend of power electronic technology in power supply modules is low voltage and high current. Selecting synchronous rectification technology in the secondary rectification circuit has become a low-loss method. Since the on-resistance of the power MOSEFT is very low, it can improve the efficiency of the power supply, so it has begun to be applied in the DC/DC converter using the isolated Buck circuit. Synchronous rectification technology is a technology that realizes the rectification function by controlling the drive circuit of the power MOSEFT. Generally, the driving frequency is fixed, about 200kHz or more, and the threshold driving can be realized by cross-coupled or external driving signal with dead time control. Synchronous rectification technology not only improves the efficiency of power supply, but also brings new progress to communication power supply modules, making synchronous rectification a mainstream power supply technology that is used in a wide range of industrial production fields.