installation and use of module igbt insulated gate bipolar

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					Installation and Use of Module IGBT - insulated gate bipolar transistor; it came out in the early 1980s and developed rapidly in1990s. IGBT has the advantages of MOSFET and GTR, it has high input impedance, high speed, good thermal stability and it is voltage-driven, it also has lower-state pressure, high voltage, and high current. Therefore, the IGBT new technologies and new techniques make new breakthroughs. It is used in the occasions of hard-switching with the frequency of 5 KHz ~ 40 KHz, soft-switch with the frequency of 40 KHz ~ 150 KHz and power from 5 KW to hundreds of KW. IGBT devices will continue to open up new application areas to provide new opportunities for efficient energy and materials, new energy and intelligent automation. In order to make good and full use of IGBT module correctly, the following are the most basic usage. (I) we must choose suitable standard modules according to the work voltage, rated current and frequency. Before using the module, we should read the module parameters table in detail, understand technical indicators of the module; according to the module technical parameters, we determine the use programme, calculate on-state losses and switching losses and choose the radiator and drive circuit. (II) The use of IGBT module 1. IGBT which can prevent static are electrostatic sensitive devices, in order to prevent the electrostatic hazards, we should pay attention to the following points: ①The black sponge on the drive terminal of IGBT module is anti-static material. Before using plug down-lead, users should remove anti-static material and stuck down-lead immediately; in the absence of anti-static measures, do not hand-to-driven terminal. ② If driven terminations need been welded, equipment or electric iron must be grounded. 2. Select and use ① please use the products within the scope of the maximum rating (voltage, current, temperature, etc.). Products may be damaged, when they work beyond the maximum rating. Especially when the voltage of IGBT goes beyond Vces, it may occur avalanche breakdown phenomenon to damage the elements, so be sure that the elements work within the scope of Vces! The higher the frequency, the smaller the current; Choose a suitable safety factor for reliability. If you need test before use IGBT, please choose the appropriate test equipment to avoid damage (particularly FRED and IGBT module need professional test equipment, do not use non-professional equipment to test its maximum voltage). ② Drive Circuit: As Vce (sat) of IGBT and short-circuit tolerance are in relations between the compromise, we suggest that the gate voltage + VG is between 14 V and 15V, -VG is between 5 V and 10V, it is necessary to ensure that the drive voltage and waveform of drive terminal can meet the requirement. Grid resistance Rg and IGBT’s open and the shutdown characteristic are closely related. If the value of Rg reduces, the switching loss and the drop-off time will reduce, and the shutdown plus voltage will increase. Conversely if the value of Rg increases, the switching loss will increase and impact switching frequency. Choose the suitable value of Rg according to the

compromise between the switching loss and surge voltage, Rg is commonly between 5Ω and 100Ω. We suggest to parallel 20 K ~ 30K Ω resistance between the grid and emission pole to prevent the gate open. The drive wiring should be as short as possible and use twisted pair. When the power switch on, please turn on the drive power first and turn on the main circuit power after the drive circuit begins to work. ③ Protection Circuit: when IGBT module is used in high-frequency, wiring inductance will lead voltage aiguilles, so we should reduce wiring inductance and scheme of element, and pay attention to the following protection items: over-current protection, over-voltage protection, gate over-voltage and under voltage protection, security work area, over-temperature protection. ④Absorbing circuit: As IGBT’s high switching speed which can easily lead a surge voltage, a surge clamping circuit is needed. ⑤ Parallel use: we should consider gate circuits, circuit routing, the current imbalance between the device and the temperature. ⑥ please avoid the corrosive gases and dust place. (III) Installation ① Radiators should be matching selectively based on the environment of application and module parameters in order to ensure requirements of radiator when module working. ② Degree of finish of radiator surface should be less than 10 mm, and plane distortions of each screw should be less than 10 mm. In order to reduce contact resistance, a layer of thin module should be smeared in the middle of the thermal silicone grease and module. After module is stressed equably, a little edge thermal silicone grease can be seen out the module as well. ③ Module is installed in the radiator, and the screw should be tightened in term of torque in preparing brochures. If torque is insufficient, it may cause resistance -increasing or screw-loosening. Is torque is too large, it may damage or destroy insulation of module; ④ When only a module is installed, it should be installed in the centre of radiator which makes heat easily. ⑤ When several modules are installed, corresponding space should be left according to heat of each module and more space should be left if heat more. ⑥ When 2 points-installment tighten screws, first tighten one third of torque in turn, and then tighten to the anti-rated torque. ⑦ In 4 points-installation same to 2 points-installation, the long direction of IGBT is along radiator veins. When tighten screws, first tighten one third of torque in turn, and then tighten to the anti-rated torque. ⑧ When use the radiator with veins, the long direction of IGBT is along radiator veins in order to reduce the deformation. If two modules are installed on a radiator, they are placed side by side in short direction and intermediate leaves sufficient distance because from the main cooling fan can reduce the superposition heat, reject of heat easily and maximize the efficiency of radiators. In addition, the terminals of module are easy to connect, and stray inductance can be reduce easily, particularly using of high-frequency is more important.

⑨ while connecting devices, connectivity can’t bring the bus terminal electrode of main module too great mechanical and thermal stress so as to avoid fever overheating when inner welding faults and terminals produce heat in electrode of modules.

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