# US 2019/0170798 A1 · Evaluation method, combined evaluation method, evaluation apparatus, and combined evaluation apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0170798 A1 - Document ID: US20190170798A1 - Status: Published application - Kind: A1 - Application number: 16/261,497 - Filed: 2019-01-29 - Published: 2019-06-06 - Earliest claimed: 2017-02-24 - Assignees: Fuji Electric Co., Ltd. - Applicants: Fuji Electric Co., Ltd. - Inventors: Hiroki KATSUMATA; Michio TAMATE; Miwako FUJITA; Tamiko ASANO; Yuhei SUZUKI; Takashi KAIMI; Yuta SUNASAKA; Tadanori YAMADA; Ryu ARAKI; Bao Cong HIU - Web page: https://patentgrep.com/patent/US20190170798A1 ## CPC - H02M 1/00: Details of apparatus for conversion - G01R 29/00: Arrangements for measuring or indicating electric quantities not covered by groups G01R19/00 - G01R27/00 - G01R 29/08: Measuring electromagnetic field characteristics - G01R 29/0814: {Field measurements related to measuring influence on or from apparatus, components or humans (EMC, EMI and similar testing in general G01R31/001), e.g. in ESD, EMI, EMC, EMP testing, measuring radiation leakage; detecting presence of micro- or radiowave emitters; dosimetry; testing shielding; measurements related to lightning} - G01R 29/0871: {Complete apparatus or systems; circuits, e.g. receivers or amplifiers (G01R29/0878, G01R29/0892 take precedence; dosimeters, warning devices G01R29/0857)} - G01R 29/26: Measuring noise figure; Measuring signal-to-noise ratio - H02M 7/217: using semiconductor devices only - H02M 7/537: using semiconductor devices only, e.g. single switched pulse inverters - H02M: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF (transformers H01F; dynamo-electric converters H02K47/00; controlling transformers, reactors or choke coils, control or regulation of electric motors, generators or dynamo-electric converters H02P) - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) ## Abstract The radiated noise of a semiconductor device is conveniently evaluated, and the radiated noise of an apparatus equipped with the semiconductor device is estimated. An evaluation method including: making a semiconductor device that is connected parallel to a load by a load cable, perform a switching operation; measuring common-mode current flowing through the load cable during the switching operation; and outputting an evaluation benchmark for radiated noise based on the common-mode current, and an evaluation apparatus are provided. ## Claims ### Claim 1 An evaluation method comprising: making a semiconductor device that is connected parallel to a load by a load cable, perform a switching operation; measuring common-mode current flowing through the load cable during the switching operation; and outputting an evaluation benchmark for radiated noise based on the common-mode current. ### Claim 2 (depends on 1) The evaluation method according to claim 1, wherein the outputting the evaluation benchmark calculates, as the evaluation benchmark for the radiated noise, radiated electric field strength of a frequency component included in the common-mode current. ### Claim 3 (depends on 1) The evaluation method according to claim 1, wherein at least part of the load cable is covered with metal shield. ### Claim 4 (depends on 3) The evaluation method according to claim 3, wherein the metal shield is electrically connected to a conductive member to which the semiconductor device is attached having an insulation material between the semiconductor device and the conductive member. ### Claim 5 (depends on 4) The evaluation method according to claim 4, wherein the conductive member is part of a temperature adjustment unit to adjust a temperature of the semiconductor device. ### Claim 6 (depends on 1) The evaluation method according to claim 1, further comprising: comparing the evaluation benchmark output for the semiconductor device and an evaluation benchmark output for a reference device different from the semiconductor device; and evaluating an intensity of the radiated noise of the semiconductor device relative to the reference device according to a result of the comparison. ### Claim 7 (depends on 1) A combined evaluation method for estimating radiated noise of an apparatus provided with the semiconductor device, the combined evaluation method comprising: acquiring a plurality of evaluation benchmarks for the semiconductor device that are output in correspondence with the switching operation under a plurality of conditions by using the evaluation method according to claim 1; and combining the plurality of evaluation benchmarks to estimate the radiated noise of the apparatus. ### Claim 8 (depends on 7) The combined evaluation method according to claim 7, wherein the combination of the evaluation benchmarks is a maximum value or a sum of the plurality of evaluation benchmarks for the semiconductor device. ### Claim 9 (depends on 7) The combined evaluation method according to claim 7, wherein the combination of the evaluation benchmarks is an average value of the plurality of evaluation benchmarks for the semiconductor device. ### Claim 10 (depends on 9) The combined evaluation method according to claim 9, wherein the combination of the evaluation benchmarks is an average value calculated after multiplying the plurality of evaluation benchmarks for the semiconductor device by respective weights corresponding to the plurality of conditions. ### Claim 11 An evaluation apparatus comprising: a load that is electrically connected parallel to a semiconductor device; a load cable electrically connecting the semiconductor device and the load; a signal supplying unit configured to supply predetermined switching signals to the semiconductor device; a detection unit configured to detect common-mode current flowing through the load cable; and an evaluation benchmark output unit configured to output evaluation benchmarks of radiated noise of the semiconductor device based on a detection result of the detection unit. ### Claim 12 (depends on 11) The evaluation apparatus according to claim 11, wherein at least part of the load cable is covered with metal shield. ### Claim 13 (depends on 12) The evaluation apparatus according to claim 12, wherein the detection unit is provided at an area different from an area of the load cable that is covered with the metal shield. ### Claim 14 (depends on 12) The evaluation apparatus according to claim 12, wherein the metal shield is electrically connected to a conductive member to which a substrate is fixed, and the semiconductor device is arranged on the semiconductor device having an insulation material between the semiconductor device and the substrate. ### Claim 15 (depends on 14) The evaluation apparatus according to claim 14, wherein the conductive member is part of a temperature adjustment unit to adjust a temperature of the semiconductor device. ### Claim 16 (depends on 11) The evaluation apparatus according to claim 11, comprising: a power supply; and a plurality of capacitive units that are each connected parallel to the semiconductor device. ### Claim 17 (depends on 16) The evaluation apparatus according to claim 16, wherein at least one capacitive unit of the plurality of capacitive units has a first capacitive element and a second capacitive element that are connected in series, and a node between the first capacitive element and the second capacitive element is connected to a reference potential. ### Claim 18 (depends on 11) The evaluation apparatus according to claim 11, wherein the semiconductor device includes a first device and a second device that are connected in series; the load cable has: a first connection line, one end of the first connection line being connected to one end of the first device; a second connection line, one end of the second connection line being connected to the other end of the first device; and a load connected between the other end of the first connection line and the other end of the second connection line; and the signal supplying unit is configured to supply the switching signal to the second device. ### Claim 19 (depends on 18) The evaluation apparatus according to claim 18, wherein the detection unit has a current probe to detect the common-mode current flowing from the first device to the load through the first connection line and the second connection line. ### Claim 20 (depends on 11) The evaluation apparatus according to claim 11, further comprising: a storage unit configured to store the evaluation benchmark output by the evaluation benchmark output unit; and a comparison unit configured to compare the evaluation benchmark output by the evaluation benchmark output unit and an evaluation benchmark for a reference device different from the semiconductor device stored in the storage unit; and an evaluation unit configured to evaluate a relative change in intensity of the radiated noise of the semiconductor device according to a result of the comparison. ### Claim 21 (depends on 11) A combined evaluation apparatus, comprising: an acquisition unit configured to acquire a plurality of evaluation benchmarks for the semiconductor device that are output by the evaluation apparatus according to claim 11 in correspondence with the switching signal under a plurality of conditions; an estimation unit configured to combine the plurality of evaluation benchmarks to estimate radiated noise of an apparatus provided with the semiconductor device.