Electric machinery of 3 water chestnut developed module of power of first 6.5kV complete SiC(Silicon Carbide) , use standard of HV100 of tall insulation compression to enclose (100mmÍ140mm) . Be emulated through electromagnetism and circuit is emulated, optimized the interior design that HV100 encloses, pass practical test test and verify stable electric character. Module of power of 6.5kV HV100 complete SiC to increase power density, siC SBD(Schottky Barrier Diode) and SiC MOSFET chip compositive together.

 

When follow on current, compositive SiC SBD can guide, and the parasitism body diode of SiC MOSFET won’t guide, avoided so bipolar degrade effect happening. The article contrasted module of Si IGBT power (Si IGBT chip and Si diode chip) , module of power of traditional complete SiC MOSFET (SiC MOSFET chip, SBD) of the buy outside notting have and module of power of new-style complete SiC MOSFET (SiC MOSFET and SiC SBD are compositive be in same a) on chip, the result shows module of power of new-style complete SiC MOSFET is below high temperature, high frequency operating mode the advantage is clear.

 

1, foreword

 

SiC material has superior physical performance, from this the performance that the SiC power module of research and development can enhance converter [1-2] . Relative to Si chip, complete SiC chip can realize taller compression, smaller loss with minorrer volume, change to drawing the design of research and development that sheds system and power transmission system brings more advantage. Module of power of 3.3kV complete SiC has gotten applied in drawing convertor, having remarkable energy-saving, reduce the effect such as converter bulk and weight [3-4] . Module of 6.5kV Si IGBT has been used at Gaotie and power transmission system, these markets expect module of 6.5kV SiC power can bring more profit. Be based on this, electric machinery of 3 water chestnut developed module of power of 6.5kV complete SiC MOSFET [5-7] , its use HV100 standard to enclose [8] , if pursue,1 is shown. This encloses to convenient and shunt-wound applying design, electric stability appears particularly important.

 

 

The article introduced 6.5kV the internal composition of module of power of new-style complete SiC MOSFET and electric character, relative to module of power of the Si IGBT module at the tradition, traditional complete SiC MOSFET, module of power of new-style complete SiC MOSFET is mixed in static character, dynamic character loss respect advantage is clear.

 

2, module of power of 6.5kV new-style SiC MOSFET is characteristic

 

2.1 The SiC-MOSFET chip of compositive SiC SBD is characteristic

 

HV100 encloses 6.5kV module of power of new-style complete SiC MOSFET uses SiC MOSFET and technology of chip of SiC SBD unifinication, wen Keda of top job ties 175 ℃ .

 

One of module design main difficult point is the parasitism body diode that avoids SiC MOSFET (PIN diode) guide, once have in PIN diode little child (hole) the cathode of diode of voltaic flow direction (the leakage of SiC MOSFET extremely) , because SiC chip is denotative the layer is characteristic, bipolar degrade the possibility of effect happening can increase. Below condition of follow on current, the falling to compare SiC MOSFET inside limits of complete electric current to saturation pressing parasitism body diode of SiC SBD wants low.

 

If the SiC MOSFET that places independently and SiC SBD chip pursue 2 (A) be shown, the area of SiC SBD is 3 times of area of SiC MOSFET chip; If SiC SBD compositive it is above SiC MOSFET chip, if pursue 2 (B) be shown, gross area is 1.05 times of area of SiC MOSFET chip more individual. Compositive use in the SiC SBD above SiC MOSFET chip perpendicular yuan of afterbirth structure, bear the weight of when follow on current all and retrorse electric current, make the parasitism body diode of SiC MOSFET chip has not shed electric current at the same time, eliminate thereby bipolar degrade effect. If the graph is shown 2 times, because chip area is reduced, module whole bulk can be reduced. Relative to module of the Si IGBT module at the tradition and power of traditional complete SiC MOSFET, the module of power of new-style complete SiC MOSFET that uses identical HV100 to enclose can realize the power density with highest industry.

 

 

2.2 Of module of power of new-style SiC MOSFET optimize a design

 

Interior of module of power of new-style complete SiC MOSFET uses 6.5kV half bridge develop attacks, general high-power application can use shunt-wound join to enhance output power. Module of tall voltage power is in next high frequency moving, inductance of the parasitism electric capacity that needs to consider module oneself, parasitism and parasitism impedance. 3D electromagnetism copy is a kind of when interior of test and verify encloses structure and chip layout effective method really. Electromagnetism interference may bring 3 kinds of bad influences: It is the voltaic feedback in switch process; 2 it is to go up, character of switch of arm playing the bridge is abhorrent; 3 it is grid voltage oscillation. Electromagnetism interference can increase chip of module interior power to decorate, the complexity that binds calm line to join electric structure designs etc.

 

Our compose built 6.5kV the in-house and equivalent circuit of module of power of new-style complete SiC MOSFET and chip model, through 3D electromagnetism is emulated and circuit is emulated, test and verify the rationality that power module designs.

 

2.2.1

 

Optimize switch speed

 

If furnish is sealed to time to did not consider electromagnetism to disturb in module, in operating condition, with respect to meeting generation the electric current in switch process feedbacks, make the inherent switch speed of chip produces change, may cause then on bridge arm and the switch speed of arm playing the bridge are abhorrent. Negative voltaic feedback can lower the switch rate of chip, the switch loss that causes chip increases, because of this switch speed lopsided can bring about module interior the heat of each chip distributings abhorrent. Graph 3 showed module of power of new-style complete SiC MOSFET is in 6.5kV what electromagnetism is disturbed and without electromagnetism interference falls emulate enlightened weaveform, can see from inside the graph, through optimizing in-house and electric design, electromagnetism disturbs module of power of new-style to 6.5kV complete SiC MOSFET to was not affected. Graph 4 for 6.5kV arm of the bridge on module of power of new-style complete SiC MOSFET is mixed the emulation of arm playing the bridge is enlightened and undee, both weaveform almost just the same, when checking actually also test and verify this.

 

 

2.2.2

 

Grid voltage oscillation is restrained

 

In module of power of high current density, interior has parallel connection of chip of a lot of power, parasitism capacitance and parasitism inductance may comprise complex syntonic circuit, cause grid voltage oscillation possibly thereby. Range of grid voltage oscillation is too big, the likelihood damages grid. The door that can increase chip interior normally extremely resistance will achieve the goal that restrains oscillation, but increase interior door pole resistor can cause switch loss to increase, when designing module, resistor of grid of our hope interior as far as possible small. Have the aid of emulates a method, below the condition that carries little grid resistance, we restrained grid voltage oscillation well through optimizing in-house and electric distribution.

 

 

Graph 5 for 6.5kV module of power of new-style complete SiC MOSFET is in before optimizing interior design, mix the grid voltage after optimizing emulates weaveform. Before optimizing, have a bigger oscillation, amplitude can amount to 13V. After optimizing, grid voltage oscillation gets inhibition, extent has 2V only, in checking actually also test and verify this.

 

2.3 Static character parameter is comparative

 

Graph 6 for 400A IGBT module (be changed from 1000A IGBT of rated electric current and come) , module of power of 400A tradition complete SiC MOSFET (do not contain SiC SBD) with 400A on-state of module of power of new-style complete SiCMOSFET is pressed fall comparative. When 150 ℃ , the on-state resistance of SiIGBT is lower, because Si IGBT is bipolar,this is parts of an apparatus, and SiC MOSFET belongs to odd polarity parts of an apparatus. Module of power of 400A tradition complete SiC MOSFET (do not contain SiC SBD) with 400A core of module of power of new-style complete SiCMOSFET is accumulated one-sidedly almost identical, it is so inside total temperature limits its on-state resistor is almost identical also.

 

Diode to pressure fall if contrast pursues 7 show 8 times with the graph. Graph 7 it is each module be in asynchronous rectification condition (MOSFET does not guide) the contrast that plays character of diode electric current, graph 8 be in for each module synchronous commutate condition (MOSFET guides) the contrast of character of next diode electric current. Can see from inside the graph, be in asynchronous below rectification condition, the expression of module of traditional SiC-MOSFET power is shown nonlinear characteristic; And module of power of new-style complete SiC MOSFET, when no matter be in,synchronous commutate returns dispute synchronism commutate, show linear trait. By go up, no matter be in MOSFET on-state, still be in diode on-state, module of power of complete SiC MOSFET shows the character of odd polarity parts of an apparatus.

 

 

 

2.4 Dynamic and characteristic parameter is comparative

 

Graph 9 it is in 3600V/400A for module of power of new-style complete SiC MOSFET below room temperature and high temperature (175 ℃ ) enlightened weaveform is comparative, can see from inside the graph, arm of the bridge on the module of power of new-style complete SiC MOSFET that optimizes through internal composition and the switch rate that arm playing the bridge leaves in room temperature and high temperature almost just the same, the loss below its room temperature and high temperature is almost so same also. Generally speaking, the addition as temperature (carry stream child life increases) , restore electric current to also can increase subsequently reversely, but like the graph 9 are shown, the retrorse extensive telegram in reply below high temperature carries on his shoulder or back (Qrr) opposite normal temperature increases very few. Like static character, module of power of new-style complete SiC MOSFET shows the character of odd polarity parts of an apparatus on dynamic character.

 

 

2.5 Weaveform of actual measurement switch and switch loss are comparative

 

Graph the 10 enlightened weaveform that are module of module of power of traditional complete SiC MOSFET and power of new-style complete SiC MOSFET are mixed in room temperature the contrast below 175 ℃ , can see from inside the graph fall in room temperature, both weaveform is very adjacent, but fall in 175 ℃ , module of power of traditional complete SiCMOSFET restores electric current reversely bigger, VDS drops rate is slower. And because module of power of new-style complete SiC MOSFET restores electric current reversely small, so its VDS drops rate is rapidder. At the same time these character show both enlightened loss is mixed restore loss to be close to very much below room temperature reversely, but fall in high temperature, the enlightened loss of module of power of new-style complete SiC MOSFET and recover loss reversely opposite smaller, main reason is retrorse when restoring, the parasitism body diode of module of power of new-style complete SiCMOSFET does not guide.

 

 

When 175 ℃ , module of power of traditional complete SiC MOSFET can have a bigger oscillation when debut, and oscillation may cause electromagnetism interference, the safety that affects module then works. In applying actually, hope this oscillation Yue Xiaoyue is good, to restrain oscillation, can rate of switch of slow down module perhaps increases exterior draw circuit. But to module of power of new-style complete SiC MOSFET, oscillation falls in high temperature very small, need not adopt extra step to restrain oscillation.

 

In module of power of high-pressured complete SiC MOSFET, the main reason that creates above difference is module of power of traditional complete SiC MOSFET have a thick extension layer, generation of the meeting when restoring reversely restores electric current more greatly reversely.

 

Graph the 11 switch loss that are module of power of module of power of Si IGBT module, traditional complete SiC MOSFET and new-style complete SiC MOSFET are comparative (Si IGBT module and module of complete SiCMOSFET power are installed respectively in optimal switch speed) . Can see from inside the graph, loss of module of power of complete SiC MOSFET is less than Si IGBT module apparently. And, when 175 ℃ , module of power of new-style complete SiC MOSFET opens loss than module of power of traditional complete SiC MOSFET low 18% , recover loss reversely low 80% .

 

 

3, loss is comparative

 

In switch frequency Fs=0.5kHz, 2kHz and 10kHz, PF=0.8, modulation compares M=1, bus voltage VCC=3600V, below the operating mode that outputs voltaic IO=200A, contrasted use Si IGBT module (150 ℃ ) , module of power of traditional complete SiC MOSFET (175 ℃ ) with module of power of new-style complete SiC MOSFET (175 ℃ ) inverter loss, if pursue,12 are shown. Can see from inside the graph, in Fs=0.5kHz, on-state loss holds very large proportion, module of power of complete SiC MOSFET is right now lower than Si IGBT module 64% , at the same time module of power of traditional complete SiC MOSFET and module of power of new-style complete SiC MOSFET differ very small.

 

In Fs=2kHz, module of power of complete SiC MOSFET is lower than Si IGBT module 85% , and module of power of new-style complete SiC MOSFET is relatively traditional module of complete SiCMOSFET power is low 7% . In Fs=10kHz, switch loss holds very large proportion, module of power of complete SiC MOSFET is right now lower than module of Si IGBT power 92% , and module of power of new-style complete SiC MOSFET is relatively traditional module of complete SiCMOSFET power is low 16% . Can see from above, module of power of new-style complete SiCMOSFET suits high frequency, high temperature application more.

 

 

4, conclusion

 

The module of power of new-style 6.5kV complete SiC MOSFET that electric machinery of 3 water chestnut developed industry head money to use HV100 to enclose. Emulate through electromagnetism, circuit is emulated and check actually, confirmed the rationality of in-house and electric design. In the meantime, module of power of new-style 6.5kV complete SiC MOSFET uses SiC SBD and design of chip of SiC MOSFET unifinication, reduced module volume, realized the power density with 6.5kV highest industry. Through the static state test and trends check, no matter guide in SiC MOSFET,affirmed module of power of new-style 6.5kV complete SiC MOSFET connect or the character that SiC SBD guides odd polarity parts of an apparatus is shown when connecting, and its SiC SBD restores electric current reversely below high temperature small, not bipolar degrade effect. Module of power of new-style 6.5kV complete SiC MOSFET guides below high temperature the VDS when connecting drops faster, its guide a loss is smaller, and happen without oscillation phenomenon.

 

In the meantime, contrasted the loss of module of Si IGBT module, power of traditional complete SiC MOSFET and module of power of new-style complete SiC MOSFET, when switch frequency is 10kHz, the module of loss ratio Si IGBT of module of power of new-style complete SiCMOSFET probably low 92% , module of power of more complete than the tradition SiC MOSFET is relatively low 16% . Relative to module of power of traditional complete SiC MOSFET, because restore to differ characteristicly reversely between diode of SiC MOSFET body and compositive SiC SBD, module of power of new-style complete SiC MOSFET is in high temperature, high frequency wait for applied operating mode to fall to have an advantage more.