WO2022149288A1 - 電力変換システム及び電力変換制御方法 - Google Patents
電力変換システム及び電力変換制御方法 Download PDFInfo
- Publication number
- WO2022149288A1 WO2022149288A1 PCT/JP2021/000585 JP2021000585W WO2022149288A1 WO 2022149288 A1 WO2022149288 A1 WO 2022149288A1 JP 2021000585 W JP2021000585 W JP 2021000585W WO 2022149288 A1 WO2022149288 A1 WO 2022149288A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- current
- converter
- voltage reference
- phase
- power
- Prior art date
Links
- 238000006243 chemical reaction Methods 0.000 title claims abstract description 128
- 238000000034 method Methods 0.000 title claims description 19
- 238000004804 winding Methods 0.000 claims description 23
- 239000013598 vector Substances 0.000 claims description 19
- 239000011159 matrix material Substances 0.000 claims description 8
- 238000004364 calculation method Methods 0.000 claims description 6
- 238000005070 sampling Methods 0.000 description 31
- 238000010586 diagram Methods 0.000 description 18
- 102100024633 Carbonic anhydrase 2 Human genes 0.000 description 16
- 101000760643 Homo sapiens Carbonic anhydrase 2 Proteins 0.000 description 16
- 239000003990 capacitor Substances 0.000 description 13
- 239000000969 carrier Substances 0.000 description 7
- 239000013256 coordination polymer Substances 0.000 description 7
- 230000004043 responsiveness Effects 0.000 description 6
- 230000009466 transformation Effects 0.000 description 6
- 238000012986 modification Methods 0.000 description 4
- 230000004048 modification Effects 0.000 description 4
- 238000012545 processing Methods 0.000 description 4
- 238000004088 simulation Methods 0.000 description 3
- 230000007423 decrease Effects 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 230000007935 neutral effect Effects 0.000 description 2
- 230000000737 periodic effect Effects 0.000 description 2
- 239000004065 semiconductor Substances 0.000 description 2
- 102100024650 Carbonic anhydrase 3 Human genes 0.000 description 1
- 101000760630 Homo sapiens Carbonic anhydrase 3 Proteins 0.000 description 1
- 230000003111 delayed effect Effects 0.000 description 1
- 238000004146 energy storage Methods 0.000 description 1
- 230000002708 enhancing effect Effects 0.000 description 1
- 230000005669 field effect Effects 0.000 description 1
- 238000007429 general method Methods 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
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
- H02M7/483—Converters with outputs that each can have more than two voltages levels
- H02M7/49—Combination of the output voltage waveforms of a plurality of converters
Definitions
- An embodiment of the present invention relates to a power conversion system and a power conversion control method.
- a power conversion system that is configured to include a power converter with a switching element and is connected to a multi-phase AC power system.
- the operation of the power converter causes switching ripple on the power system side, and it is desired to reduce this switching ripple.
- the power conversion system may be required to further enhance the control responsiveness of the current control on the power system side.
- An object to be solved by the present invention is to provide a power conversion system and a power conversion control method capable of further enhancing the control responsiveness of current control on the power system side.
- the power conversion system of the embodiment is connected to a multi-phase AC power system.
- the power conversion system includes a plurality of converters and a control unit.
- the plurality of converters are provided in parallel with each phase of the power system.
- the control unit controls the plurality of converters by carrier comparison type PWM control using a plurality of carrier signals having a predetermined phase difference from each other.
- four or more even-numbered timings are set at predetermined time intervals in one cycle of a specific carrier signal among the plurality of carrier signals, and the four or more even-numbered timings are set.
- the currents on the primary side of the plurality of converters are detected, respectively.
- the control unit generates a voltage reference for the PWM control using the detected value of the current on the primary side and the value of the current reference on the primary side, and performs the four or more even times.
- the voltage reference is updated at the timing of.
- the control unit controls a specific converter among the plurality of converters by using the specific carrier signal and the updated voltage reference.
- the figure for demonstrating the result of the simulation of the circuit structure of FIG. The figure for demonstrating the timing of the current sampling and the update of the voltage reference of the modification of the 1st Embodiment.
- the block diagram of the model of the power conversion system which made 5 converters of the 2nd Embodiment in parallel.
- the block diagram of the converter control part of the 2nd Embodiment The figure for demonstrating the timing of the current sampling and the update of the voltage reference of the 3rd Embodiment.
- the power conversion system described below supplies desired AC power to an electric motor (motor), which is an example of a load.
- the power conversion system of the embodiment includes a power converter formed to be connected to an AC power system.
- the description of connecting in the embodiment includes connecting electrically.
- FIG. 1 is a diagram showing an example of the power conversion system 1 of the embodiment.
- the power conversion system 1 includes, for example, a transformer 201, a power converter 30, and a control unit 601.
- the power conversion system 1 includes AC input terminals R, S, and T, and is connected to the AC power supply 101 (power system) via these terminals.
- the power conversion system 1 includes AC output terminals U, V, and W, and is connected to the motor 401 via these terminals.
- the primary winding of the transformer 201 is connected to the AC input terminals R, S, and T, and the AC input side of the power converter 30 is connected to the secondary winding of the transformer 201.
- the AC output side is connected to the AC output terminals U, V, and W.
- the control unit 601 controls the on / off of the switching element inherent in the cell converters 30U, 30V, and 30W.
- the cell converters 30U, 30V, and 30W are collectively referred to as a plurality of cell converters 30X.
- the transformer 201 includes a primary side winding and a secondary side winding having a three-group configuration.
- the primary winding is formed in a three-phase star connection.
- the secondary windings are formed in a three-phase open delta connection that is isolated from each other.
- Three-phase AC power is supplied to the transformer 201 from the AC power supply 101.
- the transformer 201 transforms the voltage of the AC power supplied from the AC power supply 101 to a desired voltage based on the turns ratio, and supplies the AC power of the transformed voltage to each of the plurality of cell converters 30X.
- the power converter 30 includes a plurality of cell converters 30X.
- the plurality of cell converters 30X are three first phase cell converters 30U (30U1, 30U2, 30U3) and three second phase cell converters 30V (30V1, 30V2, 30V3). , And three phase 3 cell transducers 30W (30W1, 30W2, 30W3).
- Each cell converter 30X is a single-phase converter, converts the single-phase AC power supplied from the secondary winding of the transformer 201 into DC power, and converts the converted DC power into a single unit having a desired frequency and voltage. Converts to phase AC power and outputs.
- Each cell converter 30X has the same circuit configuration. The details of this will be described later.
- the first phase of the first group on the secondary side of the transformer 201 is connected to the input of the cell converter 30U1.
- the second phase of the first group on the secondary side of the transformer 201 is connected to the input of the cell converter 30V1.
- the third phase of the first group on the secondary side of the transformer 201 is connected to the input of the cell converter 30W1.
- the first phase of the second group on the secondary side of the transformer 201 is connected to the input of the cell converter 30U2.
- the second phase of the second group of the secondary side of the transformer 201 is connected to the input of the cell converter 30V2.
- the third phase of the second group of the secondary side of the transformer 201 is connected to the input of the cell converter W2.
- the first phase of the third group on the secondary side of the transformer 201 is connected to the input of the cell converter 30U3.
- the second phase of the third group on the secondary side of the transformer 201 is connected to the input of the cell converter 30V3.
- the third phase of the third group on the secondary side of the transformer 201 is connected to the input of the cell converter W3.
- the outputs of the three first-phase cell converters 30U1, 30U2, 30U3 are connected in series in this order.
- three second-phase cell converters 30V1, 30V2, 30V3 and three third-phase cell converters 30W1, 30W2, 30W3 are also connected in series for each phase.
- the outputs of the transducer 30W1 are connected to each other to form a neutral point of the three-phase alternating current of the load circuit.
- the output of the cell converter 30U3 on the side not connected to the cell converter 30U2 is connected to the AC output terminal U and is connected to the U-phase winding of the motor 401 via the AC output terminal U.
- the output of the cell converter 30V3 on the side not connected to the cell converter 30V2 is connected to the AC output terminal V and is connected to the V-phase winding of the motor 401 via the AC output terminal V.
- the output of the cell converter 30W3 on the side not connected to the cell converter 30W2 is connected to the AC output terminal W and is connected to the W-phase winding of the motor 401 via the AC output terminal W.
- the control unit 601 controls a plurality of cell converters 30X.
- the control unit 601 includes a first control unit 610, a second control unit 620, and a third control unit 630.
- the first control unit 610 controls a plurality of cell converters 30X applied as converters described later.
- the first control unit 610 includes, for example, a converter control unit 611.
- the second control unit 620 controls a plurality of cell converters 30X applied as an inverter described later.
- the second control unit 620 includes, for example, an inverter control unit 621.
- the third control unit 630 monitors the control state of the power conversion system 1 and adjusts it so that it is controlled stably.
- the third control unit 630 includes a timer and generates an interrupt signal having a predetermined period.
- the converter control unit 611 applies the converter control unit 30X to each cell converter 30X based on the information indicating the current flowing through the secondary windings (FIGS. 2A and 2B) of the transformer 201 detected by the current sensor 301 (FIG. 3A) described later.
- Each cell converter 30X is controlled by sending a signal for controlling the included switching element to each cell converter 30X.
- the power conversion system 1 can convert the AC power supplied from the AC power supply 101 into three-phase AC power having a desired frequency and a desired voltage and supply the AC power to the motor 401. Details of the converter control unit 611 will be described later.
- the primary winding (input side) has a star (Y) connection, but this is an example, and a delta ( ⁇ ) connection may be used.
- the secondary winding (output side) is an open winding in which the three-phase winding is electrically separated into a single phase.
- the voltages applied between RN, SN, and TN are each multiplied by the number of turns, and the first on the secondary side. It appears between Rs1-Na1 and Ss1-Nb1 and Ts1-Nc1 in the group.
- the Rs1-Na1, Ss1-Nb1, and Ts1-Nc1 sections of the secondary side first group correspond to the first phase, second phase, and third phase of the secondary side first group, respectively.
- Rs2-Na2, Ss2-Nb2, and Ts2-Nc2 of the secondary side second group correspond to the first phase, the second phase, and the third phase of the secondary side second group, respectively.
- FIG. 3A to 3C are circuit diagrams showing the internal configuration of the cell converter 30X (X: U, V, W) of the embodiment.
- the cell converter 30X has input terminals IN1 and IN2 and output terminals OUT1 and OUT2.
- the cell converter 30X includes a current sensor (current transformer) 301 and a cell converter main body 302.
- the current sensor 301 detects the current flowing between the input terminals IN1 and IN2.
- the magnitude of this current is indicated by ix.
- x is an identifier that identifies the number of stages, and may be, for example, a natural number.
- FIGS. 3B and 3C show configuration examples when the cell converter 30X is a so-called two-level converter and a so-called three-level converter, respectively, and either of them may be adopted.
- the cell converter main body 302 shown in FIG. 3B includes a two-level converter in which the AC side potential changes in two stages.
- the cell converter 30X has single-phase converters on the input side and the output side, respectively, and their DC portions are connected back to back to each other.
- An energy storage element such as a capacitor C1 is connected to the DC unit.
- the voltage Vdcx is a voltage (referred to as a capacitor voltage) applied to the terminal of the capacitor C1.
- the cell converter main body 303 shown in FIG. 3C includes a diode clamp type three-level converter configured so that the AC side potential changes in three stages.
- the DC portion has capacitors CP and CN.
- the capacitor voltage it means the total voltage (Vdcx) of the capacitors CP and CN.
- IGBTs Insulated-Gate Bipolar Transistors
- MOSFETs Metal-Oxide-Semiconductor Field-Effect Transistors
- GTO Gate Turn-Off
- GCT Gate Commutated Turn-off
- FWD Free-Wheeling Diode
- the single-phase converter on the input side performs forward conversion (from alternating current).
- the single-phase converter on the output side performs reverse conversion (conversion from direct current to alternating current). Therefore, the single-phase converter on the input side is called a converter, and the single-phase converter on the output side is called an inverter.
- the cell converter main body 302 shown in FIG. 3B may be configured as a circuit unit in which the converter 3021 and the inverter 3022 are separated.
- the capacitor C1 may be a separate body from the converter 3021 and the inverter 3022, or may be housed in any circuit unit.
- the cell converter main body 302 may be configured by housing the converter 3021, the inverter 3022, and the capacitor C1 in one circuit unit.
- the cell converter main body 303 shown in FIG. 3C may be configured as a circuit unit in which the converter 3031 and the inverter 3032 are separated.
- the capacitors CP and CN may be separate from the converter 3031 and the inverter 3032, or may be housed in any circuit unit.
- the cell converter main body 303 may be configured by housing the converter 3031, the inverter 3032, and the capacitors CP and CN in one circuit unit.
- the cell converter 30X is converted into a converter (3021, 3032) by regarding the combination of the above capacitors (C1, CP, CN) and the inverter (3032, 3032) as a DC power supply DC. It can be equivalent to the combination of 3031) and the DC power supply DC.
- the converter control unit 611 of the present embodiment generates the gate pulse of the converter (3021, 3031) of the cell converter 30X by the following method.
- -A triangular wave carrier signal (referred to as a triangular wave PWM carrier (triangular wave carrier signal)) is used for PWM control of the converters (3021, 3031).
- the triangular wave PWM carrier includes, in one cycle, a first period in which the amplitude increases at a predetermined rate of change and a second period in which the amplitude decreases at a predetermined rate of change, the first period and the second period.
- the lengths of the periods are determined to be equal to each other.
- -A phase difference is provided so that the phases of the triangular wave PWM carriers in each stage are not aligned.
- the basic triangular wave PWM carrier is shifted so that the phases of the triangular wave PWM carriers in each stage have a predetermined phase difference.
- the phase difference is set to 180 / N (deg / stage), and the phase of the triangular wave PWM carrier of each stage is determined in order.
- the phase of the first-stage triangular wave PWM carrier is set to 0 by aligning with the phase of the basic triangular wave PWM carrier.
- the phase of the second-stage triangular wave PWM carrier is set to the phase of the basic triangular-wave PWM carrier plus 180 / N (deg / stage).
- the phase of the third-stage triangular wave PWM carrier is set to the phase of the basic triangular-wave PWM carrier plus 180x2 / N (deg / stage).
- the phase of each stage is determined in the same manner.
- the polarities of the voltage reference given to the input IN1 and the input IN2 of the cell converter 30X shown in FIG. 3A are inverted (referred to as single-phase unipolar modulation).
- the inverter control unit 621 may use the same triangular wave PWM carrier as described above for the PWM control of the inverters (3022, 3032) to perform control with the same phase difference. Alternatively, the inverter control unit 621 may apply another control method.
- FIG. 4 is a configuration diagram of a simplified power conversion system 1 of the embodiment.
- the DC side of the equivalent circuit of the power conversion system 1 shown in FIG. 4 is an ideal power supply, and the circuit type on the AC side is a single-phase circuit.
- the cell converters 30S1 and 30S2 correspond to the cell converters 30X.
- the input voltages of the cell converter 30S1 and the cell converter 30S2 are shown by voltage v1 and voltage v2, and the system voltage of the AC power supply is shown by voltage vs.
- the input currents of the cell converter 30S1 and the cell converter 30S2 are indicated by the current i1 and the current i2, and the system current of the AC power supply is indicated by the current is.
- L is an equivalent reactance corresponding to the transformer 201 and the like.
- the above equation (4) shows that the system current is can be controlled by using the combined voltage (v1 + v2) based on the input voltage of the cell converter 30S1 and the cell converter 30S2.
- FIG. 5 is a diagram for explaining the timing of current sampling and voltage reference update of the embodiment.
- two triangular wave PWM carriers for example, referred to as a first cell carrier Car1 (first carrier signal) and a second cell carrier Car2 (second carrier signal)
- a leg A On the upper side of the timing chart shown in FIG. 5, two triangular wave PWM carriers (for example, referred to as a first cell carrier Car1 (first carrier signal) and a second cell carrier Car2 (second carrier signal)) and a leg A.
- the change between the voltage reference vA * of the leg B and the voltage reference vB * of the leg B is shown respectively.
- the difference between the voltage reference vA * and the voltage reference vB * corresponds to the input voltage v1.
- the change in the combined voltage (v1 + v2) is shown at the bottom of the timing chart.
- Each of the times t1 to t17 is determined to have a predetermined period (Tsmp), and each is the timing of current sampling and voltage reference update.
- phase of the carrier (referred to as cell carrier) of the cell converter 30X in each stage is shifted by about a quarter cycle.
- the phase of the second cell carrier Car2 in the example shown in FIG. 5 is delayed from the phase of the first cell carrier Car1 by about one-fourth of one cycle of the triangular wave PWM carrier.
- the voltage reference of the cell converter 30S1 and the cell converter 30S2 is an example in which the polarity is inverted with the same amplitude.
- each vertex of the first cell carrier Car1 and the second cell carrier Car2, and each intermediate point between the two vertices adjacent to each other in the time axis direction (hereinafter, simply referred to as each intermediate point).
- the timing of the current sampling of the first-stage cell converter 30S1 and the update of the voltage reference may be determined based on the timing of.
- the timing of the current sampling of the second-stage cell converter 30S2 and the update of the voltage reference may be performed at the above timing.
- the apex of the cell carrier in each stage includes one or both of a positive value spire value (extreme value) and a negative value spire value (extreme value).
- the above timing may be determined by associating the points having adjacent positive spiers (extreme values) or the adjacent negative spiers (extreme).
- the timing of the apex of the first cell carrier Car1 is t1, t5, t9, t13, t17 in FIG.
- the timings of the vertices of the second cell carrier Car2 are t3, t7, t11, and t15 in FIG.
- the timing of each intermediate point is t2, t4, t6, t8, t10, 12, t14, and t16 in FIG.
- each timing from t1 to t17 becomes the timing of the current sampling of each cell converter 30X and the update of the voltage reference.
- the current sampling of the cell converter 30S1 in the first stage and the timing of updating the voltage reference are used.
- the timing of the current sampling of the second-stage cell converter 30S2 and the update of the voltage reference match. According to this, the current sampling and the voltage reference update are performed at each vertex and each intermediate point of each cell carrier of the cell converter 30S1 and the cell converter 30S2.
- the voltage reference vA * of the leg A For example, based on the magnitude relationship between the sizes of the two triangular wave PWM carriers (first cell carrier Car1 and second cell carrier Car2), the voltage reference vA * of the leg A, and the voltage reference vB * of the leg B. , It is possible to generate a combined voltage that exhibits a voltage quantized to multiple values.
- the voltage reference vA * is smaller than both the first cell carrier Car1 and the second cell carrier Car2, and the voltage reference vB * is larger than both the first cell carrier Car1 and the second cell carrier Car2.
- each switching element of each converter is controlled so that the combined voltage (v1 + v2) becomes (-2E).
- the voltage reference vA * is smaller than the first cell carrier Car1 and larger than the second cell carrier Car2, and the voltage reference vB * is larger than both the first cell carrier Car1 and the second cell carrier Car2.
- each switching element of each converter is controlled so that the combined voltage (v1 + v2) becomes ( ⁇ E).
- each switching element of each converter is controlled so that the combined voltage (v1 + v2) becomes (-0).
- the voltage reference vA * is larger than both the first cell carrier Car1 and the second cell carrier Car2, and the voltage reference vB * is smaller than the first cell carrier Car1 and larger than the second cell carrier Car2. Or, if the voltage reference vB * is smaller than both the first cell carrier Car1 and the second cell carrier Car2, and the voltage reference vA * is smaller than the first cell carrier Car1 and larger than the second cell carrier Car2.
- Each switching element of each converter is controlled so that the combined voltage (v1 + v2) becomes (+ E).
- the voltage reference vA * is larger than both the first cell carrier Car1 and the second cell carrier Car2, and the voltage reference vB * is smaller than both the first cell carrier Car1 and the second cell carrier Car2.
- each switching element of each converter is controlled so that the combined voltage (v1 + v2) becomes (+ 2E).
- Tsmp section the combined voltage (v1 + v2) of each section (referred to as the Tsmp section) divided by the period Tsmp.
- the magnitude of the combined voltage (v1 + v2) in each Tsmp interval changes discretely with the passage of time and takes multiple values.
- the converter control unit 611 controls each converter by the PWM method so that the voltage reference vA * in each Tsmp section is equal to the time average value of the instantaneous value of the combined voltage (v1 + v2) in the Tsmp section. That is, when the equation (4) is established in each of the above Tsmp intervals, the following equation (5) is also satisfied.
- the two converters 3021 connected in parallel in FIG. 4 are equivalent to a three-phase two-level inverter by repeating current sampling and voltage reference update with a periodic Tsmp. Current controllability can be obtained.
- the converter control unit 611 updates the voltage reference a plurality of times within half a cycle of the triangular wave PWM carrier as shown in FIG.
- the voltage reference vA * and the triangular wave PWM carrier intersect a plurality of times within the half cycle of the triangular wave PWM carrier.
- the timings related to the current sampling and the update of the voltage reference exist four or more even times.
- a pulse having a relatively narrow width is included.
- a pulse having a relatively narrow width for example, a pulse with a width less than the specified width, a pulse having a relatively narrow width is obtained by not switching the switching element of the converter 3021. Can be restricted from occurring.
- FIG. 6 is a diagram for explaining the result of the simulation of the circuit configuration of FIG.
- FIG. 6A shows a sampling result (I_U1_S: solid line) of the detected value (I_U1: broken line) of the current (CNV current) of the converter in the first stage.
- FIG. 6B in FIG. 6 shows a sampling result (I_U2_S: solid line) of the detected value (I_U2: broken line) of the current (CNV current) of the second-stage converter.
- C in FIG. 6 shows the change in the system current.
- the amplitude of this system current is the sampling result (I_U1_S) of the current of the first stage converter shown in (a) of FIG. 6 and the second stage shown in (b) of FIG. It is the sum with the sampling result (I_U2_S) of the current of the converter.
- the switching ripple of the system current is shown in FIG. 6 (c) is smaller than the sampling result of the current of each converter.
- the above equation (5) is established with an N-stage circuit configuration when current sampling and voltage reference update are performed at each vertex and each intermediate point of each cell carrier.
- the carrier frequency fcar of each stage and the period Tsmp have the relationship of the following equation (6).
- the period Tsmp becomes shorter as the number of stages N increases, and the control characteristics can be expected to improve accordingly.
- the circuit configuration in the case of N stages is equivalent to the circuit configuration in which N converters are connected in parallel on the secondary side of the transformer 201.
- the plurality of cell converters 30X of the power conversion system 1 are provided in parallel with each phase of the AC power supply 101 (power system).
- the converter control unit 611 controls a plurality of cell converters 30X by carrier comparison type PWM control using a plurality of carrier signals having predetermined phase differences with each other.
- the converter control unit 611 determines the timing of four or more even times with a period Tsmp (predetermined time interval) in one cycle of a specific carrier signal among a plurality of carrier signals, and four or more even times.
- the currents on the primary side of the plurality of cell converters 30X are detected at the timing of.
- the converter control unit 611 generates a voltage reference for PWM control using the detected current value ix on the primary side and the current reference value on the primary side, and timings four or more even times. Update the voltage standard respectively.
- the converter control unit 611 controls a specific cell converter among a plurality of cell converters 30X by using a specific carrier signal and an updated voltage reference. As a result, the power conversion system 1 can further enhance the control responsiveness of the current control on the AC power supply 101 side.
- FIG. 7 is a diagram for explaining the timing of current sampling and updating of the voltage reference of the modified example of the first embodiment.
- circuit of FIG. 4 described above has a path (referred to as a circulating current path) in which the current can be circulated inside the power converter 30 without affecting the system current is.
- a path referred to as a circulating current path
- the difference between the equation (2) and the equation (3) is taken and converted into an integral system to obtain the following equation (7).
- the above equation (7) shows that the circulating current (i1-i2) can be controlled by the differential voltage (v1-v2) of each converter in the power converter 30.
- current sampling and voltage reference are performed at the timing of each vertex of each cell carrier without performing current sampling and voltage reference update at both the timing of each vertex of each cell carrier and each intermediate point.
- the control can be performed in the same manner as in the first embodiment.
- the period Tsmp can be made relatively longer than that of the first embodiment. If the period Tsmp is lengthened, the responsiveness of the current control may decrease, but the concentration (density) of the arithmetic processing in each period Tsmp can be reduced.
- the timing of each vertex of each cell carrier can be changed to the timing of each intermediate point of each cell carrier.
- the switching ripple of the system current is compared with the sampling result of the current of the converter in each stage. Can be made smaller.
- Comparing the first embodiment with its modified example it is possible to improve the responsiveness of the system current is as compared with the method of the modified example of the first embodiment by applying the method of the first embodiment. It is possible. Even if the length of the periodic Tsmp is adjusted to change the density of the current sampling timing, the system current is can be stably controlled by the converter.
- the second embodiment will be described.
- the system current is is the addition of N currents corresponding to the number of parallels of each converter. Since each converter is controlled individually, the current value of each converter is not uniform. In order to reduce the influence of the variation of the current of each converter, it is preferable to calculate the average of N currents so as to match the weights of the current values of each converter, and control the system current is based on this.
- the remaining (N-1) components correspond to the circulating current components.
- Various methods can be considered for allocating the components of this circulating current, and an example is shown in the following equations (8) to (13).
- the current component corresponding to the AC side of each converter is indicated by an.
- n is an identification number of each converter. Since the system current is is electrically equal to zero, its acronym is taken and indicated by z. Circulating current is an acronym for circulation and is indicated by c 1 ... c n-1 .
- the conversion of the current component a n corresponding to each converter into the system current z and the circulating current c 1 ... c n-1 is called zc conversion.
- the reverse conversion of the zc conversion is called the reverse zc conversion.
- the component of each current indicated by an is the current before zc conversion.
- the component of each current indicated by z and c 1 ... c n-1 is the current after zc conversion.
- Equation (8) is an arithmetic expression for zc conversion
- equation (9) is an arithmetic expression for inverse zc conversion.
- Equation (12) is an arithmetic expression for zc conversion
- equation (13) is an arithmetic expression for inverse zc conversion.
- the components of the current after the zc conversion can be divided into the system current z and the circulating currents c 1 ... c n-1 .
- N By adjusting each component of the system current z and circulating current c 1 ... c n-1 after zc conversion and controlling N parallel converters based on the result of the adjustment, N It enables current control of parallel converters.
- FIG. 8 is a configuration diagram of a model of a power conversion system in which five converters of the second embodiment are arranged in parallel.
- the power converter 30 includes cell converters 30U1 to 30U5, cell converters 30V1 to 30V5, and cell converters 30W1 to 30W5.
- FIG. 9 is a configuration diagram of the converter control unit 611 of the second embodiment.
- FIG. 9 shows a converter control unit 611 and a power converter 30 related thereto.
- the power converter 30 outputs each of the current values (current values) detected by the converters in each stage.
- i_1 ⁇ uvw indicates the current value of the first stage converter.
- the current value of the first-stage converter is a value indicating the magnitude of the current detected by the current sensor 301 in the first-stage converter. The same applies below.
- the character string following "_" indicates that it is a subscript, and the character string following " ⁇ " (hat) indicates that it is a superscript.
- i_2 ⁇ uvw indicates the current value of the second stage converter.
- i_5 ⁇ uvw indicates the current value of the fifth stage converter.
- the current values (i1u, i1v, i1w (FIG.
- i_1 ⁇ uvw i_2 ⁇ uvw to i_5 ⁇ uvw.
- v1u to v5u in FIG. 8 indicate the input voltages of the U-phase cell converters 30U1 to 30U5.
- the converter control unit 611 is, for example, a dq0 conversion unit 6111, a ZC conversion unit 6112, a current control unit 6113, an inverse ZC conversion unit 6114, an inverse dq0 conversion unit 6115, a PWM control unit 6116, and a gate pulse generation unit.
- a 6117 and a current reference generation unit 6118 are provided.
- the dq0 conversion unit 6111 performs general dq0 conversion based on the current value of the converter in each stage by using the phase reference ⁇ 0 respectively.
- the dq0 transformation is a coordinate transformation that transforms a component of the stationary coordinate system into a component of the dq0 coordinate system, which is a rotating coordinate system that rotates according to the phase reference ⁇ 0.
- i_1 ⁇ dqz indicates the current vector after dq0 conversion of the first-stage converter.
- i_2 ⁇ dqz shows the current vector after dq0 conversion of the second stage converter.
- i_5 ⁇ dqz indicates the current vector after dq0 conversion of the fifth-stage converter.
- i_1 ⁇ dqz to i_5 ⁇ dqz are vectors of current components in the dq0 coordinate system.
- the ZC conversion unit 6112 performs zc conversion on the current component in the dq0 coordinate system after the dq0 conversion.
- i_z ⁇ dqz is a current vector of the system current z after zc conversion.
- i_c1 ⁇ dqz to i_c4 ⁇ dqz are current vectors of the circulating current after zc conversion.
- the current reference generation unit 6118 generates a current reference based on the magnitude of the DC voltage of each stage. A general method may be applied to generate this current reference.
- the current control unit 6113 (the description in the figure is ACR) performs current control based on the current reference generated by the current reference generation unit 6118 and determined in association with the control cycle and the current vector after zc conversion. Perform each to generate a voltage reference.
- the current vector after zc conversion includes the above i_z ⁇ dqz and i_c1 ⁇ dqz to i_c4 ⁇ dqz as elements.
- v_z ⁇ dqz * indicates a voltage reference corresponding to the system current z after zc conversion.
- v_c1 ⁇ dq * z to v_c4 ⁇ dqz * indicate the voltage reference corresponding to the circulating current after the inverse zc conversion.
- the current control unit 6113 performs an operation using a current vector including the magnitude of one system current is and the magnitude of (N-1) circulating currents as elements, and an Nth-order square matrix. It is advisable to carry out current control including. Even if the current control unit 6113 performs current control including an operation using a current vector including one system current is, (N-1) circulating currents as elements, and an Nth-order square matrix. good. By this calculation, the current control unit 6113 elements the combined voltage (v_z ⁇ dqz *) on the AC power supply 101 side and the (N-1) voltage reference corresponding to each (N-1) circulating current. It is advisable to generate a voltage vector included in the current and perform current control including this calculation.
- the inverse ZC conversion unit 6114 performs an inverse zc conversion on the voltage reference generated by the current control unit 6113, and generates the voltage reference of the dq0 coordinate system in association with each stage.
- v_1 ⁇ dqz * to v_5 ⁇ dqz * indicate the voltage reference of each stage after the inverse zc conversion.
- the inverse dq0 conversion unit 6115 performs an inverse dq0 conversion with respect to the voltage reference of each stage of the dq0 coordinate system generated by the inverse ZC conversion unit 6114 to generate the voltage reference of each stage of the uvw coordinate system.
- v_1 ⁇ uvw * to v_5 ⁇ uvw * indicate the voltage reference of each stage of each phase after the inverse dq0 conversion.
- the PWM control unit 6116 includes a carrier generation unit 6116c. Based on the triangular carrier generated by the carrier generation unit 6116c and the voltage reference of each stage generated by the inverse dq0 conversion unit 6115, a gate signal for controlling each switch of the power converter 30 is generated to generate a gate. A gate pulse based on the gate signal is supplied to each switch of the power converter 30 via the pulse generation unit 6117. As a result, the conduction state of each switch of the power converter 30 is controlled.
- the current reference vector I ⁇ d *, the current FBK vector I ⁇ d, and the voltage reference vector V ⁇ d * of each parallel converter with respect to the d-axis component are defined by Eq. (14).
- K_z is the current control gain for the system current is
- K_c1 is the current control gain for the circulating current.
- the voltage reference vector V ⁇ d * is obtained by controlling the current difference (I ⁇ (d *)-I ⁇ d) in the parallel converter format. It turns out that it is equivalent to being calculated.
- the transformation matrix M' By calculating the transformation matrix M'using the equation (17) in advance, the transformation matrix M'can be used for the calculation, and the calculation load for each control cycle can be reduced.
- FIG. 10 is a diagram for explaining the timing of current sampling and voltage reference update according to the third embodiment.
- the difference from FIG. 5 described above is that the number of carriers has changed from 2 to 3 because the number of parallels has changed from 2 to 3.
- the number of third cell carriers Car3 having a predetermined phase lag from the second cell carrier Car2 is increasing.
- the phase difference of each cell carrier is evenly spaced as described above.
- the number of timings of current sampling and voltage reference update is eight times for one cycle of the cell carrier. Since the number of parallels is 3, the combined voltage (v1 + v2 + v3) has a total of 7 stages of -3E, -2E, -E, 0, + E, + 2E, and + 3E.
- the above desired combined voltage can be generated even when the number of parallel converters is three. As the number of parallel converters increases in this way, the ratio of the step of changing the value of the quantized combined voltage to the total amplitude becomes smaller, which contributes to reducing ripple noise.
- STATCOM self-excited asynchronous compensator
- the control unit of the above-mentioned inverter (corresponding to the above-mentioned converter control unit 611) switches the above-mentioned operation mode by adjusting the circulating current flowing in the plurality of cell converters 30X, and switches the above-mentioned operation mode to obtain an AC power source (electric power). It is advisable to compensate for the ineffective power of the system) 101.
- the battery may be connected to the DC side thereof to configure the power conversion system 1A as a battery power storage device.
- the battery it is possible to charge the battery with the DC power converted from the AC power, or discharge the DC power stored in the battery as the converted AC power from the battery.
- the same control method can be applied to a system other than the drive system.
- the power conversion system is interconnected with a polyphase AC power system.
- the power conversion system includes a plurality of converter main bodies and a control unit.
- the plurality of converter bodies are provided in parallel with each phase of the power system.
- the control unit controls the plurality of converter bodies by carrier comparison type PWM control using a plurality of carrier signals having a predetermined phase difference from each other.
- four or more even-numbered timings are set at predetermined time intervals in one cycle of a specific carrier signal among the plurality of carrier signals, and the four or more even-numbered timings are set.
- Each of the plurality of converters detects the current on the primary side of the main body.
- the control unit generates a voltage reference for the PWM control using the detected value of the current on the primary side and the value of the current reference on the primary side, and performs the four or more even times.
- the voltage reference is updated at the timing of.
- the control unit controls a specific converter body among the plurality of converter bodies by using the specific carrier signal and the updated voltage reference. As a result, the power conversion system can further enhance the control responsiveness of the current control on the power system side.
- the above-mentioned control unit 601 (computer) includes, for example, a storage unit, a CPU (central processing unit), a drive unit, and an acquisition unit.
- the storage unit, the CPU, the drive unit, and the acquisition unit are connected in the control unit via, for example, a BUS.
- the storage unit includes a semiconductor memory.
- the CPU includes a processor that executes a desired process according to a software program.
- the drive unit generates a control signal for each unit of the power conversion system 1 according to the control of the CPU.
- the acquisition unit acquires the detection results of each current sensor and voltage sensor.
- the CPU of the control unit 601 controls the main circuit of each phase by the drive unit based on the detection results of the current sensor and the voltage sensor acquired by the acquisition unit.
- the control unit 601 may realize a part or all of the processing by the processing of the software program as described above, or may be realized by hardware instead. Further, the control unit 601 may be appropriately divided and configured, thereby ensuring the insulation of the circuit
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Inverter Devices (AREA)
Abstract
Description
・各段の三角波PWMキャリアの位相が揃わないように位相差を設けている。
具体的には、各段の三角波PWMキャリアの位相がを所定の位相差になるように、基本の三角波PWMキャリアをシフトしている。N段構成の場合には、その位相差を180 / N(deg / 段)にして、各段の三角波PWMキャリアの位相を順に決定している。例えば、1段目の三角波PWMキャリアの位相を、基本の三角波PWMキャリアの位相に揃えて0にする。2段目の三角波PWMキャリアの位相を、基本の三角波PWMキャリアの位相に180 / N(deg / 段)を加えた位相にする。3段目の三角波PWMキャリアの位相を、基本の三角波PWMキャリアの位相に180x2 / N(deg / 段)を加えた位相にする。以下、同様に各段の位相を決定する。
・図3Aに示すセル変換器30Xの入力IN1と、入力IN2に与える電圧基準の極性を反転させている(単相ユニポーラ変調という。)。
図5は、実施形態の電流サンプリングと電圧基準の更新のタイミングについて説明するための図である。
図6は、図4の回路構成のシミュレーションの結果を説明するための図である。図6中の(a)に、第1段目のコンバータの電流(CNV電流)の検出値(I_U1:破線)のサンプリング結果(I_U1_S:実線)を示す。図6中の(b)に、第2段目のコンバータの電流(CNV電流)の検出値(I_U2:破線)のサンプリング結果(I_U2_S:実線)を示す。図6中の(c)に、系統電流の変化を示す。この系統電流の振幅は、上記の図6中の(a)に示した第1段目のコンバータの電流のサンプリング結果(I_U1_S)と、図6中の(b)に示した第2段目のコンバータの電流のサンプリング結果(I_U2_S)との和である。図6中の(c)に示す系統電流isのスイッチングリップルは、各コンバータの電流のサンプリング結果に比べて小さくなっている。
第1の実施形態の変形例について説明する。
第1の実施形態において、各セルキャリアの各頂点と、各中間点とにおいて、電流サンプリングと電圧基準の更新を繰り返す事例について説明した。これに代えて、本変形例では、第1の実施形態の事例に対して各セルキャリアの各中間点を、制御に関わるタイミングから除き、各セルキャリアの各頂点において、電流サンプリングと電圧基準の更新を繰り返す事例について説明する。
第2の実施形態について説明する。
第2の実施形態では、第1の実施形態に示した手法を、並列数Nのコンバータに拡張した事例について説明する。系統電流isは、各コンバータの並列数に対応するN個の電流の加算になる。各コンバータは、個別に制御されるために、各コンバータの電流の値は一律にならない。各コンバータの電流のばらつきの影響を軽減させるために、各コンバータの電流値の重みを合わせるように、N個の電流の平均を算出して、系統電流isをこれに基づいて制御するとよい。なお、残りの(N-1)個の成分は、循環電流の成分に対応する。この循環電流の成分の割り付け方は様々な取り方が考えられるが、次の式(8)から式(13)にその一例を示す。
第3の実施形態について説明する。
第3の実施形態では、上述した手法を、並列数が3個のコンバータに適用した事例について説明する。この場合の構成は、図1の構成に相当する。
第4の実施形態について説明する。
第4の実施形態では、上述した手法を、電動機401を駆動させるドライブシステム以外に適用する事例について説明する。
前述の図4に示した構成例は、自励式無効電力補償装置(Static synchronous compensator(STATCOM))に適用可能である。これを等価回路ではなく、電力変換システム1Aの主回路の概略構成とする。STATCOMの場合には、複数のセル変換器30Xを、自励式インバータとして機能させる。換言すれば、セル変換器30Xのインバータ回路を除いて構成してもよい。
さらに、電池を、その直流側に接続して、電力変換システム1Aを電池電力貯蔵装置として構成してもよい。この場合、交流電力から変換した直流電力で電池を充電したり、電池に蓄えた直流電力を変換した交流電力として、電池から放電させたりすることが可能なる。
Claims (13)
- 多相交流の電力系統に連系する電力変換システムであって、
複数のスイッチを含み、前記電力系統の各相に、相ごとに並列になるように設けられた複数の変換器と、
互いに所定の位相差を有する複数のキャリア信号を用いて、前記複数の変換器をキャリア比較型のPWM制御によって制御する制御部と
を備え、
前記制御部は、
前記複数のキャリア信号の中の特定のキャリア信号の1周期の中に所定の時間間隔で4回以上の偶数回のタイミングが定められ、前記4回以上の偶数回のタイミングに夫々前記複数の変換器の1次側の電流を検出し、
前記検出した1次側の電流の値と、前記1次側の電流基準の値とを用いて前記PWM制御のための電圧基準を生成して、前記4回以上の偶数回のタイミングに夫々前記電圧基準を更新して、
前記特定のキャリア信号と前記更新された電圧基準とを用いて、前記複数の変換器の中の特定の変換器を制御する、
電力変換システム。 - 前記4回以上の偶数回のタイミングには、前記複数のキャリア信号の何れかの振幅が尖塔値になるタイミングに係る第1タイミングが含まれる、
請求項1に記載の電力変換システム。 - 前記4回以上の偶数回のタイミングには、前記複数のキャリア信号の振幅が夫々尖塔値になる第1タイミングの間のタイミングに係る第2タイミングが含まれる、
請求項1に記載の電力変換システム。 - 前記第2タイミングは、時間軸上で時間軸方向に互いに隣接する前記複数のキャリア信号の振幅が夫々尖塔値になる2つのタイミングの中間に決定されている
請求項3に記載の電力変換システム。 - 前記第2タイミングは、前記複数のキャリア信号のうち先行する第1キャリア信号が尖塔値になる第1尖塔タイミングと、前記第1キャリア信号に続く第2キャリア信号が尖塔値になる第2尖塔タイミングとの中間に決定されている
請求項3に記載の電力変換システム。 - 前記4回以上の偶数回のタイミングの回数は、前記相ごとに並列になるように設けられた複数の変換器の個数に基づいて決定されている、
請求項1に記載の電力変換システム。 - 前記相ごとに並列になるように設けられる前記複数の変換器の個数は、N個(Nは、2以上の整数。)であり、
前記制御部は、
前記電力系統に流れる系統電流の大きさと、前記N個の変換器に流す(N-1)個の循環電流との大きさを要素に含む電流ベクトルと、N次の正方行列とを用いた演算を含む電流制御によって決定する、
請求項1に記載の電力変換システム。 - 前記制御部は、
1つの前記系統電流と、前記(N-1)個の循環電流とを要素に含む電流ベクトルをさらに用いた前記演算を含む電流制御を実施する、
請求項7に記載の電力変換システム。 - 前記制御部は、
1つの前記電力系統側の合成電圧と、前記(N-1)個の循環電流に対応する電圧基準とを要素に含む電圧ベクトルを生成する前記演算を含む電流制御を実施する、
請求項7に記載の電力変換システム。 - 前記制御部は、
前記検出した1次側の電流の値に基づいて、位相基準θ0を用いて回転座標系における電流成分の情報に変換するdq0変換を実施するdq0変換部と、
前記dq0変換後の電流成分に基づいて、前記電力系統に流れる系統電流の成分と循環電流の成分とに分けるzc変換を実施するZC変換部と、
決定された電流基準と、前記zc変換後の前記系統電流の成分と前記循環電流の成分とに基づいた電流制御によって、電圧基準を生成する電流制御部と、
前記電圧基準に対して、前記zc変換の逆の変換に係る逆zc変換を実施して、前記回転座標系の電圧基準を、前記各段に対応付けて生成する逆ZC変換部と、
前記各段の前記回転座標系の電圧基準に対して前記dq0変換の逆の変換に係る逆dq0変換を前記位相基準θ0を用いて実施して、静止座標系の各段の電圧基準を生成する逆dq0変換部と、
三角波キャリア信号と、前記各段の電圧基準とに基づいて、前記特定の変換器の各スイッチング素子を制御するためのゲート信号を生成するPWM制御部と
を備える請求項1に記載の電力変換システム。 - 1次側巻線が3相スター結線であり、2次側巻線が互いに絶縁された3相オープンデルタ結線の変圧器
を備え、
前記2次側巻線には、前記複数の変換器が接続され、
前記1次側巻線には、前記電力系統から3相の交流電力が供給される、
請求項1に記載の電力変換システム。 - 多相交流の電力系統に連系する電力変換システムであって、
前記電力系統の各相に、相ごとに並列になるように設けられた第1変換器と第2変換器と、
互いに所定の位相差を有する第1キャリア信号と第2キャリア信号を含む複数のキャリア信号を用いて、前記第1変換器と前記第2変換器とをキャリア比較型のPWM制御によって制御する制御部と
を備え、
前記制御部は、
前記第1キャリア信号の1周期の中に所定の時間間隔で4回以上の偶数回のタイミングが定められ、前記4回以上の偶数回のタイミングに前記第1変換器と前記第2変換器との1次側の電流を検出し、
前記検出した1次側の電流の値と、前記1次側の電流基準の値とを用いて前記PWM制御のための電圧基準を生成して、前記4回以上の偶数回のタイミングに夫々前記電圧基準を更新して、
前記第1キャリア信号と前記更新された電圧基準とを用いて前記第1変換器を制御して、前記第2キャリア信号と前記更新された電圧基準とを用いて前記第2変換器を制御する、
電力変換システム。 - 多相交流の電力系統に連系する電力変換システムの電力変換制御方法であって、
前記電力系統の各相に、相ごとに並列になるように設けられた複数の変換器に含まれる複数のスイッチを、互いに所定の位相差を有する複数のキャリア信号を用いて制御するキャリア比較型のPWM制御において、
コンピュータによって、
前記複数のキャリア信号の中の特定のキャリア信号の1周期の中に所定の時間間隔で4回以上の偶数回のタイミングが定められ、前記4回以上の偶数回のタイミングに夫々前記複数の変換器の1次側の電流を検出させ、
前記検出した1次側の電流の値と、前記1次側の電流基準の値とを用いて前記PWM制御のための電圧基準を生成して、前記4回以上の偶数回のタイミングに夫々前記電圧基準を更新させて、
前記特定のキャリア信号と前記更新された電圧基準とを用いて、前記複数の変換器の中の特定の変換器を制御する過程、
を含む電力変換制御方法。
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/JP2021/000585 WO2022149288A1 (ja) | 2021-01-08 | 2021-01-08 | 電力変換システム及び電力変換制御方法 |
CN202180038701.2A CN115668738A (zh) | 2021-01-08 | 2021-01-08 | 电力转换系统及电力转换控制方法 |
JP2022506887A JP7313541B2 (ja) | 2021-01-08 | 2021-01-08 | 電力変換システム及び電力変換制御方法 |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/JP2021/000585 WO2022149288A1 (ja) | 2021-01-08 | 2021-01-08 | 電力変換システム及び電力変換制御方法 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2022149288A1 true WO2022149288A1 (ja) | 2022-07-14 |
Family
ID=82357906
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2021/000585 WO2022149288A1 (ja) | 2021-01-08 | 2021-01-08 | 電力変換システム及び電力変換制御方法 |
Country Status (3)
Country | Link |
---|---|
JP (1) | JP7313541B2 (ja) |
CN (1) | CN115668738A (ja) |
WO (1) | WO2022149288A1 (ja) |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2015033218A (ja) * | 2013-08-02 | 2015-02-16 | 川崎重工業株式会社 | 電力変換装置の制御装置及び制御方法 |
JP2018113792A (ja) * | 2017-01-12 | 2018-07-19 | 富士電機株式会社 | 状態検出装置 |
WO2020105121A1 (ja) * | 2018-11-20 | 2020-05-28 | 東芝三菱電機産業システム株式会社 | 電力変換装置 |
-
2021
- 2021-01-08 WO PCT/JP2021/000585 patent/WO2022149288A1/ja active Application Filing
- 2021-01-08 CN CN202180038701.2A patent/CN115668738A/zh active Pending
- 2021-01-08 JP JP2022506887A patent/JP7313541B2/ja active Active
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2015033218A (ja) * | 2013-08-02 | 2015-02-16 | 川崎重工業株式会社 | 電力変換装置の制御装置及び制御方法 |
JP2018113792A (ja) * | 2017-01-12 | 2018-07-19 | 富士電機株式会社 | 状態検出装置 |
WO2020105121A1 (ja) * | 2018-11-20 | 2020-05-28 | 東芝三菱電機産業システム株式会社 | 電力変換装置 |
Also Published As
Publication number | Publication date |
---|---|
CN115668738A (zh) | 2023-01-31 |
JP7313541B2 (ja) | 2023-07-24 |
JPWO2022149288A1 (ja) | 2022-07-14 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
Beig et al. | Space-vector-based synchronized three-level discontinuous PWM for medium-voltage high-power VSI | |
Huang et al. | Extended operation of flying capacitor multilevel inverters | |
Edpuganti et al. | Optimal pulsewidth modulation for common-mode voltage elimination scheme of medium-voltage modular multilevel converter-fed open-end stator winding induction motor drives | |
Yu et al. | Virtual voltage vector-based model predictive current control for five-phase VSIs with common-mode voltage reduction | |
Edpuganti et al. | Fundamental switching frequency optimal pulsewidth modulation of medium-voltage cascaded seven-level inverter | |
Peddapelli | Pulse width modulation: analysis and performance in multilevel inverters | |
Corzine | A hysteresis current-regulated control for multi-level drives | |
EP3389174A1 (en) | Power conversion device | |
JP2014143831A (ja) | 電力変換装置 | |
JP2004266884A (ja) | スイッチング電源式電源装置およびそれを用いた核磁気共鳴イメージング装置 | |
Ito et al. | Independent control of two permanent-magnet synchronous motors fed by a four-leg inverter | |
Jones et al. | A simple multi-level space vector modulation algorithm for five-phase open-end winding drives | |
Hussein et al. | Detailed Simulink implementation for induction motor control based on space vector pulse width modulation SVPWM | |
Sarkar et al. | A hybrid symmetric cascaded H-bridge multilevel converter topology | |
Salem | Design, implementation and control of a SiC-based T5MLC induction drive system | |
Iqbal et al. | Model predictive current control of a three-level five-phase NPC VSI using simplified computational approach | |
da Silva et al. | Voltage balancing in flying capacitor converter multilevel using space vector modulation | |
Zhang et al. | Leg-by-leg-based finite-control-set model predictive control for two-level voltage-source inverters | |
Saied et al. | On three-phase six-switches voltage source inverter: A 150° conduction mode | |
Salari et al. | A novel 49-level asymmetrical modular multilevel inverter: analysis, comparison and validation | |
JPWO2019167244A1 (ja) | 電力変換装置および電動機システム | |
CN114946116A (zh) | 旋转电机控制装置 | |
WO2022149288A1 (ja) | 電力変換システム及び電力変換制御方法 | |
Shashibhushan et al. | Starting torque and torque ripple reduction using SVPWM based vector control of induction motor with nine-level cascaded multilevel inverter fed with solar PV power | |
Zakzewski et al. | Hybrid Neutral Point Clamped Converter: Review and Comparison to Traditional Topologies |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
ENP | Entry into the national phase |
Ref document number: 2022506887 Country of ref document: JP Kind code of ref document: A |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 21917514 Country of ref document: EP Kind code of ref document: A1 |
|
WWE | Wipo information: entry into national phase |
Ref document number: 18007214 Country of ref document: US |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 21917514 Country of ref document: EP Kind code of ref document: A1 |