How to design an inverter Information 上海匹易电子科技有限公司 How to design the input rectifier Choke harmonics How to choose the right DC Bus capacity How many capacitors How to charge the DC bus capacity B6H Thyristor driver board Fuse in the DC bus Inverter basics Choose the right IGBT technology Trench – SPT Low output frequency Mechanical design of an inverter Content 上海匹易电子科技有限公司 Choose the right IGBT driver Difficulties in the development Long output cable Thermal paste for IGBT New ideas New applications Power on reset check Content 上海匹易电子科技有限公司 Line voltage drop Charge the DC bus capacitor z High inrush current Monitoring of the line voltage and DC bus voltage Charge the DC bus capacitor with a controlled DC current Line over voltage Use varistors between the phases Use one varistor between +/- DC bus Recommend input choke The input rectifier 上海匹易电子科技有限公司 2 1,5 1 0,5 0 1 1 0,5 0,5 0 0 -0,5 0,5 -1 -1 0 120 Bridge rectifier 240 360 0 120 240 0 120 240 上海匹易电子科 360 技有限公司 360 上海匹易电子科技有限公司 Input circuits w capacitor With Without capacitor The amplitude depends on the line impedance Influence of the charging current 上海匹易电子科技有限公司上海匹易电子科技有限公司 How to charge the capacitor? 上海匹易电子科技有限公司 A half controlled rectifier will reduce the cost Input - +15V ok Input – DC bus voltage above limit 上海匹易电子科技有限公司 Oscillator 20 kHz 10 us Thyristor – driver - circuit 40 us • 4) Three phase, current pulse (capacitive load) ID Id I ID Id T FI = Irms _ D Iav _ D = 2...2,5 3 phase input rectifier t Iav _ D = 31 ⋅ Id Irms _ D = 0,65...0,8 ⋅ Id 上海匹易电子科技有限公司上海匹易电子科技有限公司 1 phase inverter on 220V line 上海匹易电子科技有限公司 3 phase inverter on 400V line 上海匹易电子科技有限公司 better Why and where – choke? Line Reactor Calculation L Line reactor = V p er c e n t ag e x V p h / g r o u n d 2 x 3.14 x ƒLine x Iinput phase Calculation of line reactor 上海匹易电子科技有限公司 DC – bus – capacitor - calculation 5.1 x I DC Cp ? V ripple x 2 x 3.14 x ƒ DC ripple General rule - 20 -40 uF per Ampere Calculation of DC Bus capacitor 上海匹易电子科技有限公司 low inductive sandwich bus bar current path during commutation from plus to minus should go always in parallel each IGBT module should have it’s own capacitor if possible a lot of small capacitors have a lower inductance than one big capacitor Low inductive solution Typical solution IGBT Moduls + - + + + -- Capacitor -- ++ ++ IGBT Moduls - ++ - + - - - - + + - Capacitor Low inductance DC-link design + + - 上海匹易电子科技有限公司上 Design of DC-bus-capacitor 海匹易电子科技有限 Dc-bus-capacitors 公 In series and +/- parallel 司 low stray inductance current distribution is very well on the output Symmetry of Dc-bus Capacitors to the IGBT-half-bridge low stray inductance 上海匹易电子科技有限公司上海匹易电子科技有限公司 Flat fuse for low stray inductance design 上海匹易电子科技有限公司 Current measurement with Rogowski coil Power 1 1 0,5 0,5 0 0 -0,5 -0,5 -1 0 120 Inverter Basics I 240 360 上海匹易电子科技有限公司 -1 0 120 240 360 上海匹易电子科技有限公司 S L R L R Selbstinduktion Strom [wilk. Einheiten] rel. Spannung U/Umax PWM (Pulsweiten-Modulation) 1,2 0,9 0,6 0,3 0 S on S off 1 0 -0,3 0 30 60 90 120 150 Winkel in Grad Inverter principle / PWM 180 0 5 Zeit [wilk. Einheiten] 10 Switched on Three phase Inverter Switched off + DC capacitor The DC capacitor supports the DC supply. The current in the load is approximately sinusoidal but still contains some ripple cocked by the IGBT switching frequency. The higher the clock frequency the lower the ripple. The voltage at the output jumps from + to -. Current is flowing via the IGBT´s _ + Current flows via 1 IGBT and 1 freewheeling diode _ How the IGBTs are working Load) 上海匹易电子科技有限公司 Diode Diode Halfbridge Diode Bridge -2 phases Diode Bridge – 3 phases Inverter Components IGBT Driver IGBT with FWD IGBT-Halfbridge IGBT - Sixpack Inverter 上海匹易电子科技有限公司 GB GAL GAR GA IGBT for Inverter in different housing and chip technology 上海匹易电子科技有限公司 SEMITRANS is in accordance world wide standard SEMITRANS 2 (“34 mm”) SEMITRANS 3 (“62 mm”) SEMITRANS 4 Housing Sizes 上海匹易电子科技有限公司 Eupec ABB SEMIKRON Infineon* IGBT SPT Diodes IGBT Trench Providing a variety of IGBT chips 1 IGBT-chipsource only “in-house” 上海匹易电子科技有限公司 SEMIKRON is independent from chip suppliers Î We offer the best solution for the specific application ¾1200 V CAL-HD Diode, CAL Diode ¾ 600 V CAL-HD Diode, CAL Diode ¾1700 V CAL Diode ¾600 V Super fast best VCE(sat) / E(switch) ¾1200 V Ultra fast lowest Eswitch ¾600 V Trench lowest VCE(sat) ¾1200 V Trench lowest VCE(sat) ¾1700 V Trench lowest VCE(sat) ¾1200 V SPT best VCE(sat) / E(switch) Chip technologies for IGBTs 上海匹易电子科技有限公司 Gate NPT- IGBT Trench- IGBT Emitter Gate n n+ p p n- Emitter Gate SPT- IGBT n p n- 200 µm n- 135 µm 135 µm n+ p+ p+ Emitter Collector n+ p+ Collector Collector Infineon (2nd generation) “125” “123” Positive TC “Ultra Fast” :”Standard” Infineon (3rd generation) “126” Positive TC “Field Stop” 1200 V IGBT Technologies ABB (1st generation) “128” Positive TC “Soft Punch Through” 上海匹易电子科技有限公司 Ultrafast 125 series, KS4 3.3 Features Trench IGBT³ 126 series, KE3 1.7 Trench IGBT³ super thin wafer, KT3 1.7 28 15 25 100 100 YES Standard Parameter 123 series, DN2 V CEsat @ 25°C 2.5 E ON +E OFF per 100A Relative chip size at rated current pos. temp. coeff. of V CEsat QG* [nC] / 100A QG* [nC] / 100 mm² SPT 128 series, Unit 1.9 V 23 21 mJ 70 70 100 % YES YES YES YES - 850 1000 700 700 1000 nC 530 620 700 700 620 nC * measured @ VGE from -8V to 15V Main Parameters 上海匹易电子科技有限公司 Available Topologies Recommended Switching Frequencies 125 Ultrafast 126 Trench 128 SPT fsw [kHz] 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 SEMITRANS 1200 V Modules 上海匹易电子科技有限公司 Break chopper The break chopper is no AC/AC converter, but is used together with them. 上 If the speed of a motor is reduced, the motor works as generator and generates current. This 海 current charges the DC link to higher voltages. The rectifier blocks the current flow to the 匹 grid. The break chopper allows that the energy is transferred to heat via the break resistor. 易电子科技有限公司 R Break chopper Brake chopper Function 上海匹易电子科技有限公司 How is the current in IGBT and Diode? Rated current overload current overload and 2 Hz output Chip temperature in low output frequency application 上海匹易电子科技有限公司 Trench 200A Heatsink Case IGBT Diode rectifier 102.255 121.236 165.937 173.541 93.667 Trench 300A Trench 400A 96.995 114.182 152.485 150.156 89.175 100.932 118.680 142.165 151.967 92.911 SPT 150A 83.568 97.273 135.656 129.483 77.455 Please consider the chip size for low output frequency application like Servo drives, elevator drives, tool machine drives Minimal output frequency – 0.0001 Hz 上海匹易电子科技有限公司 IGBT driver should have Vce monitoring Under voltage monitoring It depends on the output power z Soft turn off z Vge monitoring MOSFET booster Isolation z High power – transformer z Low power – optical coupler IGBT driver 上海匹易电子科技有限公司 primary side secondary side µC compatible interface TOP BOTTOM Block diagram half bridge gate driver 上海匹易电子科技有限公司 Our solution SKYPER Driver board SEMIX 3 IGBT half bridge with spring contacts With standard devices to build up an IPM 上海匹易电子科技有限公司 Modules: 3 SKKD 1 SKM GAL 3 SKM GB - - - - - - - + + + + + + + ~ ~ ~ ~ ~ ~ ~ grid Break chopper Complete converter - inverter load 上海匹易电子科技有限公司上海匹易电子科技有限公司 Inverter with SEMiX 上海匹易电子科技有限公司 Inverter with SEMiX 上海匹易电子科技有限公司 Inverter with SEMiX SEMiX bridge SEMiX IGBT and SKYPER SEMIX Technology for 19 inch systems SEMiX bridge SEMiX IGBT and SKYPER 上海匹易电子科技有限公司 What must you consider Over voltage on the IGBT z Right snubber z Low stray inductance DC bus design Over temperature between the IGBTs z Consider the NTC behavior of the diode Turn off time of the IGBT z Min 3 us because of diode Dead time between top and bottom IGBT z Symmetrical turn on and turn off delay (3 us) Reverse recovery time of the freewheeling diode z Too small turn on gate resistor will generate a high peak current Thermal paste (copper base plate 100um, no copper base plate 50um) Over voltage on the isolation of the motor windings Important issues 上海匹易电子科技有限公司 The measurement of the paste layer thickness can be done by a „measurement comb“ (German: „Sechseck-Kamm 5 - 150 µm“) : 20 25 30 µm Heat sink Edges Measurement tines Measurement of paste layer thickness 上海匹易电子科技有限公司 Handling Keep the comb vertical Place it with two of the six edges onto the surface of the heat sink. Then scrape the comb slowly over the surface through the thermal paste layer. Measurement comb Scrape direction Thermal paste 90° Heat sink Measurement of paste layer thickness 上海匹易电子科技有限公司 Evaluation After the comb has been pulled over the surface and through the thermal paste two or three of the measurement tines were coated by the paste. If not, the next scale size of the comb must be used. The value of the paste layer thickness lies approximately between the covered and not covered tine: 20 25 30 µm 25 µm < thickness of paste < 30 µm Measurement of paste layer thickness 上海匹易电子科技有限公司上海匹易电子科技有限公司 Block diagram of a drive with difficulties – long cable 上海匹易电子科技有限公司 Possible voltage curves in motor wiring 上海匹易电子科技有限公司 Output filter to avoid isolation problems 上海匹易电子科技有限公司 Output filter to avoid isolation problems NEW Ideas for Inverter Application 上海匹易电子科技有限公司 Power 1 1 0,5 0,5 0 0 -0,5 -0,5 -1 0 120 240 Inverter – 4-Q-drive 360 上海匹易电子科技有限公司 -1 0 120 240 360 + Line reactor AC Line Line Voltage DC Link DC Link Voltage Slow charge control SKiiP signals Power Interface Control Board + LCD display + keypad User Interface Block diagram of an converter Switch mode Power Supply 上海匹易电子科技有限公司上海匹易电子科技有限公司 250 kW – 4-Q-drive Regenerative Unit for all existing inverter Elevator Sugar-centrifuge Hoists Plastic-molding-machine Dynamometer Handling and warehousing systems Solar inverter Application 上海匹易电子科技有限公司 energie counter further consumers frequency inverter with brake chopper energy counter, it will count only backflowing energy regenerative converter with SkiiPtechnology Save Energy in elevator application Brake resistor elevator motor 上海匹易电子科技有限公司 Power on reset for the driver Failure possibility 上海匹易电子科技有限公司 IGBT turned on Power on reset problem 上海匹易电子科技有限公司上海匹易电子科技有限公司 Inrush Current of the SMPS After “power on” is the IGBT-driver in a critical status Controller is starting to modulate with this IGBT Standard inverter 上海匹易电子科技有限公司 T1 T2 T3 Connect to the output of the inverter X Connect to the middle point of the capacitors Test circuit to analyze the status of the IGBTs 上海匹易电子科技有限公司 Ring modulator with 5us pulse to prevent a wrong status of the IGBT driver Ring modulator 上海匹易电子科技有限公司