# US 9,882,466 B2 · Power conversion device including an AC/DC converter and a DC/DC converter > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,882,466 B2 - Document ID: US9882466B2 - Status: Granted - Kind: B2 - Application number: 15/504,555 - Filed: 2015-09-01 - Published: 2017-08-24 - Granted: 2018-01-30 - Earliest claimed: 2014-11-11 - Assignees: Mitsubishi Electric Corporation - Applicants: Mitsubishi Electric Corporation - Inventors: Ryota Kondo; Takaaki Takahara; Satoshi Murakami; Masaki Yamada; Naohisa Uehara; Hidehiko Kinoshita - Web page: https://patentgrep.com/patent/US9882466B2 ## CPC - H02M 1/083: {for the ignition at the zero crossing of the voltage or the current} - H02M 1/0085: {Partially controlled bridges} - H02M 1/14: Arrangements for reducing ripples from DC input or output - H02M 1/4233: {using a bridge converter comprising active switches} - H02M 3/155: using semiconductor devices only - H02M 3/158: including plural semiconductor devices as final control devices for a single load - H02M 3/28: using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate AC - H02M 7/12: using discharge tubes with control electrode or semiconductor devices with control electrode - H02M 7/797: using semiconductor devices only - H02M 1/0022: {the disturbance parameters being input voltage fluctuations} - 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 - 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) - Y02B: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS ## Abstract A main circuit of a power conversion device includes: an AC/DC converter for performing power factor correction control for a single-phase AC power supply; and a DC/DC converter connected to the AC/DC converter via a DC capacitor. In order to reduce ripple voltage and ripple current for the DC capacitor, a control circuit superimposes, onto a DC current command, an AC current command having the minimum value at the zero cross phase of the single-phase AC power supply and having the maximum value at the peak phase thereof, to generate an output current command for the DC/DC converter, and performs output control for the DC/DC converter, using the output current command. ## Claims ### Claim 1 A power conversion device comprising: an AC/DC converter for performing power factor correction control for a single-phase AC power supply and converting AC power from the single-phase AC power supply, to DC power; a DC/DC converter which is connected to a DC side of the AC/DC converter and performs voltage conversion of DC power; a DC capacitor connected between positive and negative DC buses between the AC/DC converter and the DC/DC converter; and a control circuit for performing output control for the AC/DC converter and the DC/DC converter, wherein the control circuit superimposes, onto a DC current command, an AC current command decided according to information of ripple voltage derived from the DC capacitor, having a minimum value at a zero cross phase of the single-phase AC power supply and having a maximum value at a peak phase thereof, to generate an output current command for the DC/DC converter, and performs the output control for the DC/DC converter, using the output current command. ### Claim 2 (depends on 1) The power conversion device according to claim 1, wherein the AC current command is a sinewave current command having a frequency 2×(2n−1) times as high as a fundamental frequency of the single-phase AC power supply, therein n is a natural number. ### Claim 3 (depends on 2) The power conversion device according to claim 2, wherein the AC current command is generated with a phase thereof lagging by (π/2) relative to a fundamental wave obtained by converting a frequency of sinewave voltage of the single-phase AC power supply. ### Claim 4 (depends on 1) The power conversion device according to claim 1, wherein the AC current command has a waveform obtained by full-wave-rectifying a sinewave synchronized with AC voltage of the single-phase AC power supply. ### Claim 5 (depends on 1) The power conversion device according to claim 1, wherein the AC current command is a triangle wave current command having a frequency twice as high as a fundamental frequency of the single-phase AC power supply. ### Claim 6 (depends on 1) The power conversion device according to claim 1, wherein the AC current command is set such that an average value thereof within one cycle is zero. ### Claim 7 (depends on 1) The power conversion device according to claim 1, wherein an amplitude of the AC current command is determined based on of an amplitude target value of ripple voltage or ripple current of the DC capacitor. ### Claim 8 (depends on 1) The power conversion device according to claim 1, wherein an amplitude of the AC current command is determined on the basis of a capacitance target value for the DC capacitor. ### Claim 9 (depends on 1) The power conversion device according to claim 1, wherein in a case where an amplitude of the AC current command is set in advance, the control circuit adjusts DC voltage of the DC capacitor so as to reduce ripple voltage. ### Claim 10 (depends on 1) The power conversion device according to claim 1, wherein an amplitude of the AC current command is equal to or smaller than a value of the DC current command. ### Claim 11 (depends on 1) The power conversion device according to claim 1, wherein the AC/DC converter has a function of converting DC power to AC power to perform power regeneration to the single-phase AC power supply, the control circuit has two operation modes of a power-running mode for performing power transmission from the single-phase AC power supply, and a regeneration mode for performing power regeneration to the single-phase AC power supply, and in generating the output current command for the DC/DC converter by superimposing the AC current command onto the DC current command, in the regeneration mode, the control circuit keeps an amplitude, a frequency, and an initial phase of the AC current command as they are in the power-running mode, and inverts polarities of the AC current command and the DC current command from those in the power-running mode. ### Claim 12 (depends on 1) The power conversion device according to claim 1, wherein the DC capacitor is formed from an aluminum electrolytic capacitor. ### Claim 13 (depends on 1) The power conversion device according to claim 1, wherein a battery load is connected to the DC/DC converter. ### Claim 14 (depends on 2) The power conversion device according to claim 2, wherein the AC current command is set such that an average value thereof within one cycle is zero. ### Claim 15 (depends on 2) The power conversion device according to claim 2, wherein an amplitude of the AC current command is determined based on of an amplitude target value of ripple voltage or ripple current of the DC capacitor. ### Claim 16 (depends on 2) The power conversion device according to claim 2, wherein an amplitude of the AC current command is determined based on of a capacitance target value for the DC capacitor. ### Claim 17 (depends on 2) The power conversion device according to claim 2, wherein in a case where an amplitude of the AC current command is set in advance, the control circuit adjusts DC voltage of the DC capacitor so as to reduce ripple voltage. ### Claim 18 A power conversion device comprising: an AC/DC converter for performing power factor correction control for a single-phase AC power supply and converting AC power from the single-phase AC power supply, to DC power; a DC/DC converter which is connected to a DC side of the AC/DC converter and performs voltage conversion of DC power; a DC capacitor connected between positive and negative DC buses between the AC/DC converter and the DC/DC converter; and a control circuit for performing output control for the AC/DC converter and the DC/DC converter, wherein the control circuit controls the DC/DC converter with a constant duty cycle, generates a voltage command for the DC capacitor so as to contain an AC voltage component, and performs the output control for the AC/DC converter, using an output current command based on the voltage command which has a waveform obtained by full-wave-rectifying a sinewave synchronized with AC voltage of the single-phase AC power supply.