WO2012108267A1 - Appareil de conversion d'énergie et procédé de commande de celui-ci - Google Patents

Appareil de conversion d'énergie et procédé de commande de celui-ci Download PDF

Info

Publication number
WO2012108267A1
WO2012108267A1 PCT/JP2012/051562 JP2012051562W WO2012108267A1 WO 2012108267 A1 WO2012108267 A1 WO 2012108267A1 JP 2012051562 W JP2012051562 W JP 2012051562W WO 2012108267 A1 WO2012108267 A1 WO 2012108267A1
Authority
WO
WIPO (PCT)
Prior art keywords
voltage
detection value
voltage detection
power
switching
Prior art date
Application number
PCT/JP2012/051562
Other languages
English (en)
Japanese (ja)
Inventor
亮二 松井
敏史 伊瀬
友史 三浦
浩明 柿ヶ野
正隆 野村
Original Assignee
シャープ株式会社
国立大学法人大阪大学
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by シャープ株式会社, 国立大学法人大阪大学 filed Critical シャープ株式会社
Publication of WO2012108267A1 publication Critical patent/WO2012108267A1/fr

Links

Images

Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • 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
    • H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
    • H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
    • H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
    • H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H02M7/53—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
    • H02M7/537—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters
    • H02M7/5387—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a bridge configuration
    • H02M7/53871—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a bridge configuration with automatic control of output voltage or current
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • 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
    • H02M1/00—Details of apparatus for conversion
    • H02M1/12—Arrangements for reducing harmonics from ac input or output
    • H02M1/123—Suppression of common mode voltage or current
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • 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
    • H02M1/00—Details of apparatus for conversion
    • H02M1/14—Arrangements for reducing ripples from dc input or output
    • H02M1/15—Arrangements for reducing ripples from dc input or output using active elements

Definitions

  • the present invention relates to a power conversion device and a control method thereof, and more particularly to a power conversion device linked to a single-phase three-wire power system and a control method thereof.
  • the power converter connected to the single-phase three-wire commercial power system converts the DC power generated by the distributed power supply device into AC power and supplies it to the commercial power system.
  • a configuration is adopted in which AC power of a commercial power system is converted to DC power and supplied to equipment.
  • This type of power converter is composed of an inverter bridge composed of a plurality of switching elements and an interconnected relay.
  • the inverter bridge converts DC power to AC power by PWM (pulse width modulation) control, and connects Some are configured to be supplied to two wires (R-phase wire, T-phase wire) other than the neutral wire of the single-phase three-wire commercial power system via a system relay.
  • a smoothing circuit composed of two capacitors connected in series is connected to the DC side of the inverter bridge in order to suppress fluctuations in the input voltage to the inverter bridge.
  • the midpoint of these two capacitors is connected to the neutral point of the single-phase three-wire commercial power system.
  • the two capacitors do not necessarily output the same voltage due to factors such as changes in the characteristics of the inverter bridge, control errors in PWM control, and leakage from the parasitic capacitance of the wiring. This causes a problem of unbalance. If voltage imbalance occurs between the two capacitors, the ground voltage at the midpoint of the two capacitors may become unstable.
  • the present invention has been made to solve such a problem, and an object of the present invention is to stabilize a ground voltage on the DC side in a power conversion apparatus linked to a single-phase three-wire power system. That is.
  • the power converter is linked to a single-phase three-wire AC power system.
  • the power converter includes a smoothing circuit including first and second capacitors connected in series between a DC positive bus and a DC negative bus, and a DC terminal of the smoothing circuit connected to a DC terminal of the smoothing circuit, and a plurality of switching elements.
  • a power conversion circuit that performs power conversion between the power and AC power of the power system, a DC terminal voltage of the smoothing circuit, a first DC voltage between the DC positive bus and the midpoint of the smoothing circuit, and a DC negative bus,
  • a voltage sensor for detecting a second DC voltage between the middle points of the smoothing circuit and a control device for controlling the power conversion operation of the power conversion circuit are provided.
  • the midpoint of the smoothing circuit is electrically connected to the neutral point of the power system.
  • the control device includes a first switching control unit for switching control of the plurality of switching elements based on a deviation between the DC voltage target value and the voltage detection value between the DC terminals of the voltage sensor, and the first DC of the voltage sensor.
  • a second switching control unit configured to perform switching control of the plurality of switching elements based on a deviation between the voltage detection value and the second DC voltage detection value;
  • the second switching control unit discharges the first capacitor between the smoothing circuit and the power system when the first DC voltage detection value is larger than the second DC voltage detection value.
  • the plurality of switching elements are subjected to switching control so that the current circulation path is formed.
  • the second switching control unit discharges the second capacitor between the smoothing circuit and the power system when the second DC voltage detection value is larger than the first DC voltage detection value.
  • the plurality of switching elements are subjected to switching control so that the current circulation path is formed.
  • the first switching control unit sets the duty ratio of the plurality of switching elements based on a deviation between the DC voltage target value and the DC terminal voltage detection value.
  • the second switching control unit calculates an ON period of the switching element for discharging the first or second capacitor based on a deviation between the first DC voltage detection value and the second DC voltage detection value. Then, the duty ratio is corrected according to the calculated ON period.
  • the power conversion device further includes a wiring for connecting the midpoint of the smoothing circuit and the neutral point of the power system.
  • a method for controlling a power converter connected to a single-phase three-wire power system wherein the power converter is connected in series between a DC positive bus and a DC negative bus.
  • a smoothing circuit comprising the first and second capacitors, and a power converter connected to a DC terminal of the smoothing circuit and performing power conversion between the DC power of the smoothing circuit and the AC power of the power system by a plurality of switching elements Voltage sensor for detecting a circuit, a DC terminal voltage of the smoothing circuit, a first DC voltage between the DC positive bus and the midpoint of the smoothing circuit, and a second DC voltage between the DC negative bus and the midpoint of the smoothing circuit Including.
  • the midpoint of the smoothing circuit is electrically connected to the neutral point of the power system.
  • the control method includes a step of controlling the power conversion operation of the power conversion circuit.
  • the controlling step includes a step of performing switching control of the plurality of switching elements based on a deviation between the DC voltage target value and the voltage detection value between the DC terminals of the voltage sensor, the first DC voltage detection value of the voltage sensor, and the second And switching control of the plurality of switching elements based on a deviation from the detected DC voltage value.
  • the step of performing switching control of the plurality of switching elements based on a deviation between the first DC voltage detection value and the second DC voltage detection value includes the first DC voltage detection value being the second DC voltage detection value.
  • the plurality of switching elements are subjected to switching control so that a current circulation path for discharging the first capacitor is formed between the smoothing circuit and the power system.
  • the step of performing switching control of the plurality of switching elements based on a deviation between the first DC voltage detection value and the second DC voltage detection value includes the second DC voltage detection value being the first DC voltage detection value.
  • the plurality of switching elements are subjected to switching control so that a current circulation path for discharging the second capacitor is formed between the smoothing circuit and the power system.
  • the step of performing switching control of the plurality of switching elements based on the deviation between the DC voltage target value and the detected voltage value between the DC terminals of the voltage sensor includes the deviation between the DC voltage target value and the detected voltage value between the DC terminals. Based on this, the duty ratios of the plurality of switching elements are set.
  • the step of switching controlling the plurality of switching elements based on the deviation between the first DC voltage detection value and the second DC voltage detection value includes the first DC voltage detection value and the second DC voltage detection value. Based on the deviation, the ON period of the switching element for discharging the first or second capacitor is calculated, and the duty ratio is corrected according to the calculated ON period.
  • the voltage of the two capacitors By switching control of the power conversion circuit in accordance with the difference, a current circulation path for discharging the capacitor can be formed between the smoothing circuit and the power system. Thereby, the voltage imbalance of the two capacitors can be kept in balance, and the ground voltage at the midpoint of the smoothing circuit can be stabilized.
  • FIG. 1 is a diagram schematically showing an overall configuration of a DC power supply system to which a power conversion device according to an embodiment of the present invention is applied. It is a circuit diagram which shows the detailed structure of the DC / AC converter in FIG. It is a figure explaining the power conversion operation
  • FIG. 5 is a time waveform diagram for explaining the switching control shown in FIG. 4. It is a figure which shows the control structure of the control part in FIG. It is a figure which shows the modification 1 of the control structure of the control part in FIG.
  • FIG. 1 is a diagram schematically showing an overall configuration of a DC power supply system to which a power converter according to an embodiment of the present invention is applied.
  • the DC power supply system includes a DC bus 1, a photovoltaic power generation system 2, a storage battery system 3, and a grid power system 4.
  • the DC bus 1 supplies DC power to the DC load group 5.
  • the DC load group 5 is, for example, an electric device such as an air conditioner, a refrigerator, a washing machine, a television, a lighting device, or a personal computer used at home. Alternatively, it may be an electric device such as a computer, a copier or a facsimile used in an office, or an electric device such as a showcase or a lighting device used in a store.
  • a solar power generation system 2, a storage battery system 3, and a grid power system 4 are connected to the DC bus 1.
  • DC power supply system a case will be described in which each of DC bus 1, solar power generation system 2, storage battery system 3, grid power system 4, and DC load group 5 is provided.
  • DC bus 1, solar power generation system 2, storage battery system 3, grid power system 4, and DC load group 5 is provided.
  • the DC bus 1 is composed of a positive bus PL and a negative bus NL, which are a pair of power lines.
  • the photovoltaic power generation system 2 includes a solar cell 20 and a DC / DC converter 30.
  • the DC / DC converter 30 is disposed between the solar cell 20 and the DC bus 1, converts the DC power received from the solar cell 20 into a voltage, and supplies it to the DC bus 1.
  • the voltage conversion operation in the DC / DC converter 30 is performed by a control unit (not shown) according to the output voltage of the solar battery 20 and the voltage of the DC bus 1 (the line voltage between the positive bus PL and the negative bus NL). It is controlled according to the switching command.
  • the storage battery system 3 includes a storage battery 10 and a DC / DC converter 12.
  • the storage battery 10 is a chargeable / dischargeable power storage element, and typically includes a secondary battery such as a lithium ion secondary battery or a nickel metal hydride battery. As an example, the storage battery 10 has a rated voltage of 380 V and 10 Ah.
  • the DC / DC converter 12 is disposed between the storage battery 10 and the DC bus 1, converts the DC power received from the storage battery 10 into a voltage, and supplies it to the DC bus 1. Further, the DC / DC converter 12 converts the DC power received from the DC bus 1 into a voltage and supplies it to the storage battery 10.
  • the voltage conversion operation in the DC / DC converter 12 is controlled according to a switching command from a control unit (not shown) according to the output voltage of the storage battery 10 and the voltage of the DC bus 1.
  • the grid power system 4 exchanges DC power with the DC bus 1.
  • the grid power system 4 includes a DC / AC converter 50, an AC / DC converter 70, and a grid power 40.
  • System power 40 is power received from an electric power company or the like (for example, AC 200V).
  • the system power 40 is supplied from a single-phase three-wire commercial AC power system.
  • the neutral wire is grounded via the resistor Rg1
  • AC 200V is supplied using two wires other than the neutral wire (R-phase wire RL and T-phase wire TL). Supply.
  • the DC / AC converter 50 and the AC / DC converter 70 are connected in parallel between the DC bus 1 and the system power 40.
  • the DC / AC converter 50 converts the DC power received from the DC bus 1 into AC power and supplies it to the system power 40.
  • the AC / DC converter 70 converts AC power received from the system power 40 into DC power and supplies it to the DC bus 1.
  • system power is purchased from an electric power company or the like via the AC / DC converter 70 (power purchase), and surplus power is supplied from the electric power company or the like via the DC / AC converter 50. It is possible to sell to (power sale).
  • FIG. 2 is a circuit diagram showing a detailed configuration of the DC / AC converter 50 in FIG.
  • DC / AC converter 50 includes capacitors Ch and Cl, DC / AC converter 52, interconnection reactors 54 and 56, DC voltage detectors 58, 62 and 64, and a controller. 60.
  • the capacitors Ch and Cl are connected in series between the positive bus PL and the negative bus NL constituting the DC bus 1 to constitute a smoothing circuit.
  • Capacitors Ch and Cl have the same capacity. Thereby, an intermediate potential between the positive bus PL and the negative bus NL can be generated at the midpoint of the capacitors Ch and Cl (point B in the figure). Further, the midpoint B of the capacitor Ch and the capacitor Cl is grounded via the resistor Rg2. Therefore, for example, when the line voltage between positive bus PL and negative bus NL is 380 V (rated voltage of storage battery 3), the potentials at positive bus PL, negative bus NL, and midpoint B are +190 V, -190 V, ground potential, respectively. (0V).
  • the DC / AC converter 52 converts the DC power received from the DC bus 1 into AC power according to the switching control signals S1 to S4 from the controller 60, and outputs the AC power to the system power 40.
  • the DC / AC converter 52 includes transistors Q1 to Q4, which are switching elements, and diodes D1 to D4. Transistors Q1 and Q3 are connected in series between positive bus PL and negative bus NL constituting DC bus 1. An intermediate point between transistors Q1 and Q3 is connected to R-phase line RL. Interconnection reactor 54 is connected to R-phase line RL.
  • Transistors Q2 and Q4 are connected in series between positive bus PL and negative bus NL. An intermediate point between transistors Q2 and Q4 is connected to T-phase line TL. Interconnection reactor 56 is connected to T-phase line TL. Between the collector and emitter of each of the transistors Q1 to Q4, diodes D1 to D4 that flow current from the emitter side to the collector side are respectively connected.
  • IGBTs Insulated Gate Bipolar Transistors
  • MOSFET Metal Oxide Semiconductor Field-Effect Transistor
  • the DC voltage detection unit 58 is connected between the positive bus PL and the negative bus NL, detects the DC power voltage Vdc supplied from the DC bus 1 to the DC / AC converter 50, and the detection result is a control unit. Output to 60.
  • the DC voltage detection unit 62 is connected between the positive bus PL and the midpoint B, detects the voltage Vdc_h across the capacitor Ch (corresponding to the voltage between the positive bus PL and the midpoint B), and detects it. The result is output to the control unit 60.
  • the DC voltage detector 64 is connected between the middle point B and the negative bus NL, detects the voltage Vdc_l (corresponding to the voltage between the middle point B and the negative bus NL) at both ends of the capacitor Cl, and detects this. The result is output to the control unit 60.
  • control unit 60 Based on voltage Vdc received from DC voltage detection unit 58, voltage Vdc_h received from DC voltage detection unit 62, and voltage Vdc_l received from DC voltage detection unit 64, control unit 60 follows control structure described below. Switching control signals S1 to S4 for controlling on / off of the transistors Q1 to Q4 are generated, and the DC / AC converter 52 is controlled.
  • the control unit 60 generates the switching control signals S1 to S4 so that the DC voltage Vdc becomes a predetermined voltage target value Vdc *.
  • Voltage target value Vdc * can be determined in advance, such as 380 V, and stored in a storage unit (not shown). Or you may make it acquire a desired voltage value suitably by communicating between the control part 60 and the exterior of a direct-current power feeding system.
  • the control unit 60 uses the transistors Q1 and Q4 as one set of switch pairs, the transistors Q2 and Q3 as another set of switch pairs, and alternately sets two sets of switch pairs. Turn on and off. In FIG. 3, only the switch pair in the on state is represented by a solid line.
  • the control unit 60 turns off the switch pair of the transistors Q2 and Q3, while switching the transistors Q1 and Q4.
  • the pair is turned on / off at a predetermined duty ratio (the ratio of the on period to the switching period of the transistors Q1 to Q4).
  • the current flows from the DC side to the AC side through the transistors Q1 and Q4 during the ON period of the transistors Q1 and Q4, thereby energizing from the DC side to the AC side.
  • the electromagnetic energy in the current smoothing connected reactors 54 and 56 is returned to the DC side through the system power 40 and the diodes D2 and D3. If the electromagnetic energy in the current smoothing reactors 54 and 56 decreases during the off period of the transistors Q1 to Q4, the circuit is not energized.
  • the control unit 60 turns off the switch pair of the transistors Q1 and Q4, while switching the switch pair of the transistors Q2 and Q3. Turn on / off at a predetermined duty ratio.
  • this period 2 current flows from the DC side to the AC side through the transistors Q 2 and Q 3 during the ON period of the transistors Q 2 and Q 3, thereby energizing from the DC side to the AC side.
  • the off period of the transistors Q1 to Q4 the electromagnetic energy in the current smoothing connected reactors 54 and 56 is returned to the DC side through the system power 40 and the diodes D1 and D4. If the electromagnetic energy in the current smoothing reactors 54 and 56 decreases during the off period of the transistors Q1 to Q4, the circuit is not energized.
  • the voltage Vdc_h of the capacitor Ch with respect to the original switching control signals S1 to S4 generated based on the voltage target value Vdc *. And a correction process for compensating for an imbalance between the voltage Vdc_l of the capacitor Cl.
  • FIG. 4 is a diagram for explaining switching control for compensating for the voltage imbalance of the capacitors Ch and Cl.
  • phase point potential correction period A period for correcting the potential at the middle point B of the smoothing circuit (hereinafter referred to as “middle point potential correction period”) is provided between the periods.
  • the controller 60 fixes the transistors Q1 to Q4 on and off so that the voltage Vdc_h of the capacitor Ch and the voltage Vdc_l of the capacitor Cl are equal. For example, when the voltage Vdc_h of the capacitor Ch is larger than the voltage Vdc_l of the capacitor Cl, the transistor Q1 is fixed on and the transistors Q2 to Q4 are fixed off as shown in FIG.
  • the transistor Q1 to the interconnection reactor 54 to the R phase line RL to the neutral point A to the resistance Rg1 to A current circulation path from the ground to the resistance Rg2 to the middle point B for discharging the capacitor Ch is formed, and a discharge current flows through the current circulation path.
  • the voltage Vdc_h of the capacitor Ch is equal to the voltage Vdc_l of the capacitor Cl and the midpoint potential correction period ends, all of the transistors Q1 to Q4 are turned off.
  • FIG. 6 is a time waveform diagram for explaining the switching control shown in FIG.
  • FIG. 6 shows time waveforms of the switching control signals S1 and S4 in the period 1 shown in FIGS.
  • FIG. 6 shows switching control signals S1, S4 for controlling on / off of the transistors Q1, Q4.
  • the switching control signals S2 and S3 for turning on / off the transistors Q2 and Q3 are fixed to the L (logic low) level in the period 1, and therefore are not shown.
  • switching control signals S1, S4 having a predetermined duty ratio are output from the control unit 60.
  • the transistors Q1 and Q4 are both turned on.
  • transistors Q1 and Q4 are both turned off.
  • Control unit 60 calculates a voltage deviation from the difference between voltage Vdc_h received from DC voltage detection unit 62 and voltage Vdc_l received from DC voltage detection unit 64, and calculates a midpoint potential correction period according to the voltage deviation. To do.
  • the switching control signals S1 and S4 have the ⁇ T when the switching control signal S1 is at the H level. It is corrected so as to become longer.
  • the switching control signal S1 is corrected so that the period during which it is at the H level is T + ⁇ T / 2
  • the switching control signal S4 is such that the period during which it is at the H level is T ⁇ T / 2. It is corrected.
  • the transistor Q1 can be fixed on, while the transistor Q4 can be fixed off, and a current circulation path for discharging the capacitor Ch shown in FIG. 5 is formed. Can do.
  • the switching control signals S1 and S4 have a period during which the switching control signal S4 is H level longer by the midpoint potential correction period ⁇ T. It is corrected as follows. Thereby, in the midpoint potential correction period, the transistor Q4 can be fixed on, while the transistor Q1 can be fixed off, and a current circulation path for discharging the capacitor Cl can be formed.
  • the middle point B of the capacitors Ch and Cl is electrically connected to the neutral point A of the single-phase three-wire commercial AC power system.
  • a current circulation path for discharging the capacitor Ch or Cl can be formed between the smoothing circuit and the system power 40 via the DC / AC converter 50.
  • the voltage Vdc_h of the capacitor Ch and the voltage Vdc_l of the capacitor Cl can be kept in balance, and the ground voltage at the midpoint B of the smoothing circuit can be stabilized.
  • FIG. 7 is a diagram showing a control structure of the control unit 60 in FIG.
  • control unit 60 includes subtraction units 600, 603 to 605, addition units 601, 602, PI control units 610, 615, carrier wave comparators 611-614, NOT circuits 621, 624, including.
  • the subtraction unit 600 calculates a voltage deviation from the difference between the DC voltage Vdc and the voltage target value Vdc *, and outputs the voltage deviation to the PI control unit 610.
  • the PI control unit 610 includes at least a proportional element (P) and an integral element (I: integral element). When the voltage deviation is received from the subtraction unit 600, the PI control unit 610 corresponds to the input voltage deviation.
  • a duty ratio d is calculated as a ratio of the on period to the switching period (carrier wave signal period) of each of the transistors Q1 to Q4.
  • the subtraction unit 605 calculates a voltage deviation from the difference between the voltage Vdc_h and the voltage Vdc_l and outputs the voltage deviation to the PI control unit 615.
  • the PI controller 615 When the PI controller 615 receives the voltage deviation from the subtractor 605, the PI controller 615 calculates the ON period of the transistor as the midpoint potential correction period according to the input voltage deviation. Then, the PI control unit 615 calculates a correction amount ⁇ d of the duty ratio necessary to ensure the calculated on period.
  • the addition unit 601 adds the duty ratio correction amount ⁇ d input from the PI control unit 615 to the duty ratio d input from the PI control unit 610 to generate a duty ratio command (d + ⁇ d). Adder 601 outputs the generated duty ratio command to carrier wave comparator 611.
  • the addition unit 602 adds the duty ratio correction amount ⁇ d input from the PI control unit 615 to the duty ratio d input from the PI control unit 610 to generate a duty ratio command (d + ⁇ d). Adder 602 outputs the generated duty ratio command to carrier wave comparator 612.
  • the subtraction unit 603 subtracts the duty ratio correction amount ⁇ d input from the PI control unit 615 from the duty ratio d input from the PI control unit 610 to generate a duty ratio command (d ⁇ d).
  • Adder 601 outputs the generated duty ratio command to carrier wave comparator 613.
  • the subtraction unit 604 subtracts the duty ratio correction amount ⁇ d input from the PI control unit 615 from the duty ratio d input from the PI control unit 610 to generate a duty ratio command (d ⁇ d).
  • Adder 602 outputs the calculated duty ratio command to carrier wave comparator 614.
  • the carrier wave comparator 611 compares the duty ratio command (d + ⁇ d) with a carrier wave signal (for example, a triangular wave signal), inverts a binary signal corresponding to the comparison result by the NOT circuit 621, and turns on / off the transistor Q1.
  • a switching control signal S1 for controlling OFF is generated.
  • the carrier wave comparator 612 compares the duty ratio command (d + ⁇ d) and the carrier wave signal, and generates a switching control signal S2 for controlling on / off of the transistor Q2 composed of a binary signal according to the comparison result.
  • the carrier wave comparator 613 compares the duty ratio command (d ⁇ d) with the carrier wave signal, and generates a switching control signal S3 for controlling on / off of the transistor Q3 composed of a binary signal according to the comparison result. To do.
  • the carrier wave comparator 614 compares the duty ratio command (d ⁇ d) with the carrier wave signal, inverts a binary signal corresponding to the comparison result by the NOT circuit 624, and controls on / off of the transistor Q4.
  • the switching control signal S4 is generated.
  • FIG. 7 the configuration in which the switching control signals S1 to S4 are corrected by adding / subtracting the correction amount ⁇ d to / from the duty ratio d of each switching control signal has been described. As shown, only one of the two switching control signals respectively corresponding to the two transistors constituting one switch pair may be corrected.
  • a period during which only the transistor Q1 is turned on by controlling the switching control signal S1 to be continuously at the H level even after the switching control signal S4 has transitioned to the L level (midpoint potential correction period).
  • the midpoint potential correction period may be provided at any timing.
  • the switching control signal S1 may be shifted to the H level before the switching control signal S4.
  • a period in which only the switching control signal S1 is at the H level may be provided at a timing different from the period in which the switching control signals S1 and S4 are at the H level.
  • the bipolar switching system has been described as the switching control of the power converter, but the application of the present invention is not limited to the bipolar switching system.
  • the present invention applies to all switching methods in which an energy transmission period for turning on the transistors Q1 and Q4 or the transistors Q2 and Q3 and a midpoint potential correction period for turning on any one of the transistors Q1 to Q4 are provided. It is possible to apply.
  • FIG. 8 is a diagram showing a first modification of the control structure of the control unit 60 in FIG.
  • control unit 60A according to the first modification is different from the control unit 60 shown in FIG. 7 in that the subtraction units 603 and 604 are not provided.
  • the adding unit 601 adds the duty ratio correction amount ⁇ d input from the PI control unit 615 to the duty ratio d input from the PI control unit 610 to generate a duty ratio command (d + ⁇ d). Generate.
  • the carrier wave comparator 611 compares the duty ratio command (d + ⁇ d) with the carrier wave signal, inverts a binary signal corresponding to the comparison result by the NOT circuit 621, and performs switching for controlling on / off of the transistor Q1.
  • a control signal S1 is generated.
  • the addition unit 602 adds the duty ratio correction amount ⁇ d input from the PI control unit 615 to the duty ratio d input from the PI control unit 610 to generate a duty ratio command (d + ⁇ d).
  • the carrier wave comparator 612 compares the duty ratio command (d + ⁇ d) and the carrier wave signal, and generates a switching control signal S2 for controlling on / off of the transistor Q2, which is a binary signal corresponding to the comparison result.
  • the carrier wave comparator 613 compares the duty ratio d with the carrier wave signal, and generates a switching control signal S3 for controlling on / off of the transistor Q3 composed of a binary signal according to the comparison result.
  • the carrier wave comparator 614 compares the duty ratio d and the carrier wave signal, inverts a binary signal corresponding to the comparison result by the NOT circuit 624, and controls the switching control signal S4 for controlling on / off of the transistor Q4. Is generated.
  • the midpoint is obtained by adding the correction amount ⁇ d to the duty ratio d of one of the two switching control signals respectively corresponding to the two transistors constituting one switch pair. A potential correction period is secured.
  • FIG. 9 is a diagram illustrating a second modification of the control structure of the control unit 60 in FIG.
  • control unit 60B according to the second modification is different from the control unit 60 illustrated in FIG. 7 in that the addition units 601 and 602 are not provided.
  • the subtracting unit 603 subtracts the duty ratio correction amount ⁇ d input from the PI control unit 615 from the duty ratio d input from the PI control unit 610 to obtain a duty ratio command (d ⁇ d ) Is generated.
  • the carrier wave comparator 611 compares the duty ratio command (d ⁇ d) with the carrier wave signal, inverts a binary signal corresponding to the comparison result by the NOT circuit 621, and controls on / off of the transistor Q1. Switching control signal S1 is generated.
  • the subtraction unit 604 subtracts the duty ratio correction amount ⁇ d input from the PI control unit 615 from the duty ratio d input from the PI control unit 610 to generate a duty ratio command (d ⁇ d).
  • the carrier wave comparator 612 compares the duty ratio command (d ⁇ d) with the carrier wave signal, and generates a switching control signal S2 for controlling on / off of the transistor Q2 composed of a binary signal according to the comparison result. To do.
  • the carrier wave comparator 613 compares the duty ratio d with the carrier wave signal, and generates a switching control signal S3 for controlling on / off of the transistor Q3 composed of a binary signal according to the comparison result.
  • the carrier wave comparator 614 compares the duty ratio d and the carrier wave signal, inverts a binary signal corresponding to the comparison result by the NOT circuit 624, and controls the switching control signal S4 for controlling on / off of the transistor Q4. Is generated.
  • the midpoint is obtained by subtracting the correction amount ⁇ d from one duty ratio d of two switching control signals respectively corresponding to two transistors constituting one switch pair. A potential correction period is secured.
  • the middle point B and the single-phase three-wire are grounded by grounding the middle point B of the capacitors Ch and Cl constituting the smoothing circuit via the resistor Rg2.
  • the DC / AC converter in which the neutral point A of the AC power system is electrically connected has been illustrated, but the present invention relates to the neutral point B of the smoothing circuit and the neutrality of the single-phase three-wire AC power system.
  • the present invention can be applied to a DC / AC converter in which the point A is electrically connected.
  • the present invention is applicable to a configuration in which the midpoint B of the smoothing circuit is connected to a neutral line of a single-phase three-wire AC power system.
  • a resistor Rg ⁇ b> 3 is inserted and connected to the neutral line connecting the neutral point B of the smoothing circuit and the neutral point A of the single-phase three-wire AC power system.
  • the resistor Rg3 is connected to prevent an excessive current from flowing between the neutral point B and the neutral point A.
  • the resistor Rg3 does not necessarily need to be connected to the neutral line.
  • the resistance Rg3 includes a wiring impedance of a neutral line connecting the neutral point B and the neutral point A.
  • FIG. 11 is a circuit diagram showing a detailed configuration of the AC / DC converter 70 in FIG.
  • AC / DC converter 70 has basically the same circuit configuration as DC / AC converter 50 shown in FIG. 2, and includes capacitors Ch and Cl, AC / DC converter 72, and the like. Interconnection reactors 74, 76, DC voltage detection units 78, 82, 84, and control unit 80.
  • Capacitors Ch and Cl are connected in series between the positive bus PL and the negative bus NL. A midpoint B of the capacitors Ch and Cl is grounded via a resistor Rg2.
  • the AC / DC converter 72 converts the AC power received from the system power 40 into DC power according to the switching control signals S11 to S14 from the controller 80, and outputs the DC power to the DC bus 1.
  • AC / DC conversion unit 72 includes transistors Q11 to Q14, which are switching elements, and diodes D11 to D14.
  • Transistors Q11 and Q13 are connected in series between positive bus PL and negative bus SL.
  • An intermediate point between transistors Q11 and Q13 is connected to R-phase line RL.
  • Interconnection reactor 74 is connected to R-phase line RL.
  • Transistors Q12 and Q14 are connected in series between positive bus PL and negative bus SL. An intermediate point between transistors Q12 and Q14 is connected to T-phase line TL. Interconnection reactor 76 is inserted and connected to T-phase line TL. Between the collector and emitter of each of the transistors Q11 to Q14, diodes D11 to D14 that flow current from the emitter side to the collector side are respectively connected.
  • IGBTs can be used as the transistors Q11 to Q14.
  • a power switching element such as a power MOSFET may be used.
  • DC voltage detector 78 is connected between positive bus PL and negative bus NL, detects voltage value Vdc of DC power supplied from AC / DC converter 72 to DC bus 1, and controls the detection result. To the unit 80.
  • DC voltage detection unit 82 is connected between positive bus PL and midpoint B, and detects voltage Vdc_h across capacitor Ch (corresponding to the voltage between positive bus PL and midpoint B) and detects it. The result is output to the control unit 80.
  • the DC voltage detector 84 is connected between the middle point B and the negative bus NL, detects the voltage Vdc_l (corresponding to the voltage between the middle point B and the negative bus NL) at both ends of the capacitor Cl, and detects that. The result is output to the control unit 80.
  • control unit 80 Based on voltage Vdc received from DC voltage detection unit 78, voltage Vdc_h received from DC voltage detection unit 82, and voltage Vdc_l received from DC voltage detection unit 84, control unit 80 follows control structure described below. Switching control signals S11 to S14 for controlling on / off of the transistors Q11 to Q14 are generated, and the AC / DC converter 72 is controlled.
  • the control unit 80 generates the switching control signals S11 to S14 so that the DC voltage Vdc becomes a predetermined voltage target value Vdc *.
  • Voltage target value Vdc * can be determined in advance, such as 380 V, and stored in a storage unit (not shown). Or you may make it acquire a desired voltage value suitably by communicating between the control part 80 and the exterior of a direct current power supply system.
  • control unit 80 turns off the switch pair of transistors Q11 and Q12 while turning on / off the switch pair of transistors Q13 and Q14 at a predetermined duty ratio.
  • period 1_1 electromagnetic current is accumulated in interconnection reactors 74 and 76 due to current flowing through transistors Q13 and Q14.
  • the connection point between the diodes D11 and D13 and the connection point of the diodes D12 and D14 is between.
  • the electromagnetic energy emitted from the interconnecting reactors 74 and 76 is received, and this electromagnetic energy is rectified to DC power.
  • the transistors Q11 to Q14 are all turned off in the period 2 in which AC power is rectified to DC power by the diodes D11 and D14 constituting the bridge circuit. It is good also as composition which carries out synchronous rectification as an ON state.
  • the control unit 80 When the DC voltage Vdc is larger than the voltage target value Vdc *, the control unit 80 reduces the duty ratio of the switch pair so as to reduce the energy transmitted to the DC side, that is, to shorten the period 1_1. Let On the other hand, when the DC voltage Vdc is smaller than the voltage target value Vdc *, the control unit 80 increases the duty ratio of the switch pair so as to increase the energy transmitted to the DC side, that is, to lengthen the period 1_1. Increase.
  • FIG. 13 shows a state where the power conversion operation is performed by a control mode different from FIG.
  • control unit 80 turns off the switch pair of transistors Q13 and Q14, and turns on / off the switch pair of transistors Q11 and Q12 at a predetermined duty ratio.
  • period 1_2 In the on period of transistors Q11 and Q12 (hereinafter referred to as “period 1_2”), current flows through transistors Q11 and Q12, and electromagnetic energy is accumulated in interconnection reactors 74 and 76.
  • the interconnection reactor 74 between the connection point of the diodes D11 and D13 and the connection point of the diodes D12 and D14, the electromagnetic energy emitted from 76 is received, and this electromagnetic energy is rectified into DC power.
  • the control unit 80 When the DC voltage Vdc is larger than the voltage target value Vdc *, the control unit 80 reduces the duty ratio of the switch pair so as to reduce the energy transmitted to the DC side, that is, to shorten the period 1_2. Let On the other hand, when the DC voltage Vdc is smaller than the voltage target value Vdc *, the control unit 80 increases the duty ratio of the switch pair so as to increase the energy transmitted to the DC side, that is, to lengthen the period 1_2. Increase.
  • FIG. 13 in the ON period (period 1_2) of the transistors Q11 and Q12, as shown in FIG. 13A, electromagnetic energy is accumulated in the interconnecting reactors 74 and 76, and at the same time, FIG.
  • the neutral point A, the resistance Rg1, the ground, the resistance Rg2, the middle point B, the capacitor Ch, the transistor Q11, and the interconnection reactor 74 in order to discharge the capacitor Ch between the smoothing circuit and the system power 40, the neutral point A, the resistance Rg1, the ground, the resistance Rg2, the middle point B, the capacitor Ch, the transistor Q11, and the interconnection reactor 74, as shown in FIG.
  • Current circulation path is formed, and a discharge current flows through this current circulation path. That is, the capacitor Ch is discharged during the ON period (period 1_2) of the transistors Q11 and Q12.
  • the capacitor Cl is discharged in the on-period (period 1_1) of the transistors Q13 and Q14.
  • capacitor Ch is discharged during the on period (period 1_2) of transistors Q11 and Q12.
  • the control mode of FIG. 12 and the control mode of FIG. 13 are switched and executed.
  • FIG. 14 is a diagram for explaining switching control for compensating for the voltage imbalance of the capacitors Ch and Cl.
  • control unit 80 compares voltage Vdc_h of capacitor Ch with voltage Vdc_l of capacitor Ch, and according to the comparison result, FIG. One of the switching control shown in A) and the switching control shown in FIG.
  • transistors Q11 and Q12 are turned off in a half cycle of the system power as described in FIG.
  • Transistors Q13 and Q14 are turned on / off at a predetermined duty ratio.
  • the capacitor Cl can be discharged in the on period (period 1_1) of the transistors Q13 and Q14.
  • the middle point B of the capacitors Ch and Cl is electrically connected to the neutral point A of the single-phase three-wire commercial AC power system.
  • a current circulation path for discharging the capacitor Ch or Cl can be formed between the smoothing circuit and the system power 40 via the AC / DC converter 70.
  • the voltage Vdc_h of the capacitor Ch and the voltage Vdc_l of the capacitor Cl can be kept in balance, and the ground voltage at the midpoint B of the smoothing circuit can be stabilized.
  • FIG. 15 is a diagram showing a control structure of the control unit 80 in FIG.
  • control unit 80 includes a subtraction unit 800, a PI control unit 802, a carrier wave comparator 804, a selection unit 806, and a comparison unit 808.
  • the subtraction unit 800 calculates a voltage deviation from the difference between the DC voltage Vdc and the voltage target value Vdc *, and outputs the voltage deviation to the PI control unit 802.
  • the PI control unit 802 includes at least a proportional element P and an integration element I.
  • the PI control unit 802 changes the switching period (carrier wave) of each of the transistors Q11 to Q14 according to the input voltage deviation.
  • the duty ratio d as a ratio of the ON period to the signal period) is calculated.
  • the carrier wave comparator 804 compares the duty ratio d with a carrier wave signal (for example, a triangular wave signal), and performs switching control for controlling on / off of the transistors Q11 to Q14 composed of binary signals according to the comparison result. Signals S11 to S14 are generated. Specifically, carrier wave comparator 804 uses switching control signals S11 and S12 for controlling on / off of the switch pair of transistors Q11 and Q12 as one set of switching control signals, and sets the switch pair of transistors Q13 and Q14. Two sets of switching control signals (S11, S12) and (S13, S14) are generated using the switching control signals S13 and S14 as another set of switching control signals in order to control on / off.
  • a carrier wave signal for example, a triangular wave signal
  • the comparison unit 808 compares the voltage Vdc_h received from the DC voltage detection unit 82 and the voltage Vdc_l received from the DC voltage detection unit 84. Then, the comparison unit 808 outputs a signal indicating the comparison result to the selection unit 806.
  • the selection unit 806 selects one of the two sets of switching control signals (S11, S12) and (S13, S14) based on the comparison result signal received from the comparison unit 808. Specifically, when it is determined from the comparison result signal that the voltage Vdc_h is larger than the voltage Vdc_l, the selection unit 806 selects the switching control signal (S11, S12). In this case, the selection unit 806 fixes the non-selected switching control signals (S13, S14) to the L level.
  • the selection unit 806 selects the switching control signal (S13, S14). In this case, the selection unit 806 fixes the non-selected switching control signals (S11, S12) to the L level.
  • the AC / DC converter in this embodiment is provided with a midpoint potential correction period by the control method shown in FIG. 14, but as shown in FIG. 4B, any of the transistors Q11 to Q14 is provided.
  • the potential at the midpoint B may be corrected by providing a period during which one of them is turned on.
  • the middle point B and the single-phase three-wire are connected by grounding the middle point B of the capacitors Ch and Cl constituting the smoothing circuit via the resistor Rg2.
  • the AC / DC converter in which the neutral point A of the AC power system is electrically connected is illustrated.
  • the present invention relates to the neutral point B of the smoothing circuit and the neutrality of the single-phase three-wire AC power system.
  • the present invention can be applied to an AC / DC converter in which the point A is electrically connected.
  • the present invention is applicable to a configuration in which the midpoint B of the smoothing circuit is connected to a neutral line of a single-phase three-wire AC power system.
  • the present invention can be used for a power converter connected to a single-phase three-wire AC power system.

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Inverter Devices (AREA)

Abstract

L'invention concerne un convertisseur CC/CA (50) raccordé à un réseau de distribution électrique à courant alternatif de type monophasé à trois fils (40). Un circuit de lissage, comprenant des condensateurs (Ch, Cl) branchés en série, se trouve du côté CC du convertisseur CC/CA (50). Le point central (B) du circuit de lissage est raccordé au point neutre du réseau de distribution électrique à courant alternatif (40). Une unité de commande (60) comprend : une première unité de commande de commutation qui commande la commutation des transistors (Q1-Q4) composant un circuit en pont complet en fonction d'un écart entre une valeur de tension CC voulue et une valeur de tension entre les bornes CC détectée par un détecteur de tension (58) ; et une deuxième unité de commande de commutation qui commande la commutation des transistors (Q1-Q4) en fonction de l'écart entre une valeur de tension CC détectée par un détecteur de tension (62) et une valeur de tension CC détectée par un détecteur de tension (64).
PCT/JP2012/051562 2011-02-10 2012-01-25 Appareil de conversion d'énergie et procédé de commande de celui-ci WO2012108267A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2011-027481 2011-02-10
JP2011027481A JP5734010B2 (ja) 2011-02-10 2011-02-10 電力変換装置およびその制御方法

Publications (1)

Publication Number Publication Date
WO2012108267A1 true WO2012108267A1 (fr) 2012-08-16

Family

ID=46638484

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2012/051562 WO2012108267A1 (fr) 2011-02-10 2012-01-25 Appareil de conversion d'énergie et procédé de commande de celui-ci

Country Status (2)

Country Link
JP (1) JP5734010B2 (fr)
WO (1) WO2012108267A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US12021476B2 (en) 2021-10-29 2024-06-25 Stmicroelectronics S.R.L. Adaptive rectification for preventing current inversion in motor driving

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP6048928B2 (ja) * 2012-10-23 2016-12-21 パナソニックＩｐマネジメント株式会社 電力変換装置
JP6025045B2 (ja) * 2012-12-04 2016-11-16 富士電機株式会社 インバータ
JP2014240767A (ja) * 2013-06-11 2014-12-25 シャープ株式会社 地絡検出装置
JP6155983B2 (ja) * 2013-08-30 2017-07-05 オムロン株式会社 パワーコンディショナおよび分散型電源システム
DE102015111804B3 (de) * 2015-07-21 2016-12-15 Sma Solar Technology Ag Verfahren zum betrieb eines wechselrichters und wechselrichter, sowie photovoltaikanlage
JP6545566B2 (ja) * 2015-08-07 2019-07-17 シャープ株式会社 電力変換装置

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH06233537A (ja) * 1993-02-01 1994-08-19 Toshiba Corp 中性点クランプ式コンバータの制御装置
JPH0775345A (ja) * 1993-09-01 1995-03-17 Hitachi Ltd 電力変換装置
JPH0974766A (ja) * 1995-09-08 1997-03-18 Hitachi Ltd 電力変換装置
JPH09121559A (ja) * 1995-10-24 1997-05-06 Toshiba Fa Syst Eng Kk インバータ装置
JP2008289211A (ja) * 2007-05-15 2008-11-27 Shindengen Electric Mfg Co Ltd 系統連系インバータ装置
JP2009201248A (ja) * 2008-02-21 2009-09-03 Toshiba Mitsubishi-Electric Industrial System Corp クランプ式電力変換装置

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH06233537A (ja) * 1993-02-01 1994-08-19 Toshiba Corp 中性点クランプ式コンバータの制御装置
JPH0775345A (ja) * 1993-09-01 1995-03-17 Hitachi Ltd 電力変換装置
JPH0974766A (ja) * 1995-09-08 1997-03-18 Hitachi Ltd 電力変換装置
JPH09121559A (ja) * 1995-10-24 1997-05-06 Toshiba Fa Syst Eng Kk インバータ装置
JP2008289211A (ja) * 2007-05-15 2008-11-27 Shindengen Electric Mfg Co Ltd 系統連系インバータ装置
JP2009201248A (ja) * 2008-02-21 2009-09-03 Toshiba Mitsubishi-Electric Industrial System Corp クランプ式電力変換装置

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US12021476B2 (en) 2021-10-29 2024-06-25 Stmicroelectronics S.R.L. Adaptive rectification for preventing current inversion in motor driving

Also Published As

Publication number Publication date
JP5734010B2 (ja) 2015-06-10
JP2012170189A (ja) 2012-09-06

Similar Documents

Publication Publication Date Title
US8508957B2 (en) Power conversion device for converting DC power to AC power
US8842452B2 (en) 3-phase high power UPS
US8116103B2 (en) Device for feeding electric energy into a power grid and DC converter for such a device
US8228699B2 (en) Power converting apparatus including half-bridge inverters connected between positive and negative terminals of a DC power supply
US9041251B2 (en) Boost converter with multiple inputs and inverter circuit
US8994216B2 (en) Power conversion apparatus
US8400792B2 (en) Power conversion apparatus
US8154893B2 (en) Three-phase power converting apparatus
JP6558506B2 (ja) 電力変換器
JP3221828B2 (ja) 電力変換方法及び電力変換装置
JP5734010B2 (ja) 電力変換装置およびその制御方法
WO2012144399A1 (fr) Système d'alimentation électrique en c.c.
US12003193B2 (en) Coupled inductors inverter topology
US20200091831A1 (en) Power Conversion Device and Three-Phase Power Conversion Device
US11196290B2 (en) Uninterruptible power supply apparatus
US11336114B2 (en) Uninterruptible power supply apparatus
KR101627620B1 (ko) 무정전 전원장치
KR102391590B1 (ko) 전력 변환 장치
JP2011229347A (ja) 電力変換装置
US11955908B2 (en) Auto-configurable energy storage system
CN110308341B (zh) 能量变换系统中的逆变模块检测方法、装置及系统
JP2022189601A (ja) パワーコンディショナ
Kalpana et al. Unity power factor operation of three-phase AC-DC converter based on modular approach for telecom applications

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 12745141

Country of ref document: EP

Kind code of ref document: A1

DPE2 Request for preliminary examination filed before expiration of 19th month from priority date (pct application filed from 20040101)
NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 12745141

Country of ref document: EP

Kind code of ref document: A1