High power density inverter (II)

• US 10,312,801 B2
• Filed: 06/23/2016
• Issued: 06/04/2019
• Est. Priority Date: 07/09/2015
• Status: Active Grant

• Current Assignee: CE+T Power Luxembourg S.A.
• Original Assignee: CE+T Power Luxembourg S.A.
• Inventors: Bleus, Paul, Joannes, Thierry, Milstein, Francois, Stassain, Pierre, Frebel, Fabrice
• Primary Examiner(s): Torres-Rivera, Alex
• Application Number:
  US15/743,054
• Publication Number:
  US 20180205314A1
• Time in Patent Office: 1,076 Days
• Field of Search: 363 40, 363 47, 363 48, 363 65, 363 71, 363 97, 363 98, 363120, 363123, 363131, 363132, 363146, 363147
• CPC Class Codes: H02M 1/0058 by employing soft switching techniques, i.e. commutation of transistors when applied voltage is zero or when current flow is zero using an auxiliary actively switched resonant commutation circuit connected to an intermediate DC voltage or between two push-pull branches of an inverter bridge H02M7/4811; in resonant inverters H02M7/4815; in inverters operating from a resonant DC source H02M7/4826
• CPC Class Codes: H02M 1/123 Suppression of common mode voltage or current
• CPC Class Codes: H02M 1/126 using passive filters
• CPC Class Codes: H02M 1/143 using compensating arrangements for reducing noise from the supply in transmission systems H04B15/005
• CPC Class Codes: H02M 1/15 using active elements
• CPC Class Codes: H02M 1/44 Circuits or arrangements for compensating for electromagnetic interference in converters or inverters
• CPC Class Codes: H02M 7/4811 having auxiliary actively switched resonant commutation circuits connected to intermediate DC voltage or between two push-pull branches
• CPC Class Codes: H02M 7/5387 in a bridge configuration
• CPC Class Codes: H03K 17/133 in field-effect transistor switches
• CPC Class Codes: H05K 3/0061 onto a metallic substrate, e.g. a heat sink heat sinks for electric apparatus H05K7/20
• CPC Class Codes: H05K 7/209 Heat transfer by conduction from internal heat source to heat radiating structure H05K7/20909 takes precedence
• CPC Class Codes: H05K 7/20909 Forced ventilation, e.g. on heat dissipaters coupled to components
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

The present invention relates to a single phase, non-insulated, miniaturized DC/AC power inverter having an output power density higher than 3000 W/dm³, wherein said power inverter is packaged in a casing made of an external electrically conductive enclosure containing a fan blowing in an axial direction to a side face of the casing and, in a stacked elevation arrangement, successively from a bottom side to a top side, a layer of active filter capacitors, a heatsink, a layer of wideband semiconductors switches connected to a PCB with thermal vias and a layer of active filtering inductors, the fan and the component stacked arrangement being designed so as, in operation, the external temperature of the casing does not overcome 60° C. in any point, for an ambient temperature of maximum 30° C. under a maximum load of 2 kVA.

Claims

1. A single phase, non-insulated, miniaturized DC/AC power inverter (1) having an output power density higher than 3000 W/dm³ and comprising:

a DC input;

an AC output;

at least a H full-bridge topology switching circuit (201, 202) having an input connected to the DC input and an output connected to the AC output, and comprising switches made of wide-band semiconductors and preferably of gallium nitride or GaN semiconductors;

at least one common mode noise Electromagnetic Interference (EMI) filter (100) connected between the DC input and the input of the H full-bridge switching circuit, between the output of the H full-bridge switching circuit and the AC output respectively, said common mode noise filters (100) being referenced to an earth shielding or directly to earth (204), said common noise filters (100) comprising filtering inductors and so-called Y capacitors;

at least one differential mode noise Electromagnetic Interference (EMI) filter (101) connected, in series with a corresponding common mode noise filter (100), between the DC input and the input of the H full-bridge switching circuit, between the output of the H full-bridge switching circuit and the AC output respectively, said differential mode noise filters (101) comprising so-called X filtering capacitors and optionally inductors;

a ripple-compensating active filter comprising a switching half-bridge topology (203) provided in parallel with the H full-bridge switching circuit and connected to a LC filter, made of at least one inductor (L6) and at least one storage capacitor (C5);

wherein said power inverter (1) is packaged in a casing made of an external electrically conductive enclosure (501) containing a fan blowing in an axial direction to a side face of the casing and, in a stacked elevation arrangement, successively from a bottom side to a top side, a layer of active filter capacitors (514), a heatsink (512), a layer of wideband semiconductors switches (509) connected to a Printed Circuit Board (PCB) with thermal vias (510) and a layer of active filtering inductors (504), the fan and the component stacked arrangement being designed so as, in operation, an external temperature of the casing does not overcome 60°

C. in any point, for an ambient temperature of maximum 30°

C. under a maximum load of 2 kVA.

2. The DC/AC power inverter of claim 1, wherein the layer of active filter capacitors (514) is composed of Printed Circuit Board (PCB) mounted (513) rows of regularly spaced multilayer ceramic capacitors (MLCC), said capacitors being separated by a gap, said gap being preferably of about 1 mm and oriented in the blowing direction of the fan.

3. The DC/AC power inverter of claim 1, wherein the heatsink (512) is a one-piece machined metallic heatsink selected from the group consisting of a multiple blades, honeycomb, interlaced-fins and metal foam heatsink, said heatsink (512) being adjacent to the layer of active filter capacitors (514).

4. The DC/AC power inverter of claim 1, wherein the casing external conductive enclosure (501) surrounds a conductive shielding (503) separated thereof by a thermally conductive interface made of a gap pad (502).

5. The DC/AC power inverter of claim 1, wherein the active filtering inductors (504) are composed of ferrite cores on which Litz wire is directly wound without a coil former, each inductor (504) being made of two coils separated by a ceramic foil (505) placed between the ferrites cores in order to create an air gap as well as thermal drain.

6. The DC/AC power inverter of claim 1, wherein the layer of wideband semiconductors switches (509) connected to a PCB with thermal vias (510) is adjacent the heatsink thanks to a ceramic insulation (511) and microspring contacts (507), silicone foam (508) being provided in gaps in order to uniformly spread switch contact pressure on the heatsink (512).

7. The DC/AC power inverter of claim 4, wherein the casing enclosure (501), the conductive shielding (503) and the heatsink (512) are made of copper.

8. The DC/AC power inverter of claim 1, wherein the common mode and differential mode Electromagnetic Interference (EMI) filters, are separated from the rest in the casing.

9. The DC/AC power inverter of claim 1, wherein part of the active filtering inductors (504) are thermally fastened to a conductive shield (503).