JP6289925B2 - Power converter and control method of power converter - Google Patents

Description

  Embodiments described herein relate generally to a power conversion device and a method for controlling the power conversion device.

  There has been proposed a power conversion device (multilevel power conversion device) in which unit converter cells connected to a storage battery device on the series side are connected in series (cascade) in each phase. In such a power converter, the DC power output from the power storage device is converted into AC by controlling the switching elements of each unit converter cell.

  When the AC side of the unit converter cell is connected in multiple stages, the charge / discharge power flows uniformly to each phase of the U phase, V phase, and W phase, so it is connected to the DC side of each unit converter cell. It was not possible to charge and discharge the storage battery devices individually.

  On the other hand, in order to estimate the deterioration of the storage battery, a method (actual capacity calculation method) has been proposed in which the storage battery is charged from a fully discharged state to a full charge and the battery capacity is calculated by integrating the charging current value.

JP 2011-223734 A

Shigenori Inoue and three others, "6.6kV Transless Power Storage System Using Cascade PWM Converter and Secondary Battery-200V, 10kV, 3.6kWh Mini Model Experimental Verification", IEEJ Transactions D, Vol . 129, no. 1, pp. 67

  An object of an embodiment of the present invention is to provide a highly reliable power conversion device.

According to the embodiment, the semiconductor switch includes a semiconductor switch that switches the connection between the alternating current side and the direct current side, the alternating current side is connected in cascade, and the storage battery device is connected to the direct current side of the unit converter cell; An SOC balance control unit that generates a voltage command value for PWM control so that the remaining energy of the assembled battery becomes equal, and when measuring the battery capacity of the assembled battery individually, the target assembled battery is set, A voltage command value is corrected by adding a preset correction value to the voltage command value of the unit converter cell for the target assembled battery, and a gate signal for the semiconductor switch is generated using the corrected voltage command value. There is provided a power conversion device including a converter control device having a gate signal correction unit.

FIG. 1 is a diagram schematically illustrating a configuration example of a power conversion device according to an embodiment. FIG. 2 is a diagram schematically illustrating a configuration example of a unit converter cell and a storage battery device of the power conversion device illustrated in FIG. 1. FIG. 3 is a diagram schematically illustrating another configuration example of the assembled battery of the storage battery device illustrated in FIG. 2. FIG. 4 is a diagram schematically showing another configuration example of the assembled battery of the storage battery device shown in FIG. 2. FIG. 5 is a block diagram illustrating a configuration example of the converter control device of the power conversion device according to the first embodiment. FIG. 6 is a block diagram illustrating a configuration example of the gate signal generation shown in FIG. FIG. 7 is a diagram for explaining an example of an operation for generating a voltage command value from a voltage command value. FIG. 8 is a flowchart illustrating an example of a method for calculating the battery capacity of the assembled battery in the power conversion device according to the first embodiment. FIG. 9 is a diagram for explaining an example of a method for calculating the actual capacity of the assembled battery. FIG. 10 is a flowchart illustrating an example of a method for calculating the battery capacity of the assembled battery in the power conversion device of the second embodiment. FIG. 11 is a block diagram illustrating another configuration example of the gate signal generation shown in FIG. FIG. 12 is a diagram for explaining another example of the operation for generating the voltage command value from the voltage command value. FIG. 13 is a flowchart for explaining an example of a method for calculating the battery capacity of the assembled battery in the power conversion device of the third embodiment.

  Hereinafter, a power conversion device and a method for controlling the power conversion device according to an embodiment will be described with reference to the drawings.

FIG. 1 is a diagram schematically illustrating a configuration example of the power conversion device according to the first embodiment.
The power conversion device of this embodiment is a three-phase power conversion device including a U phase, a V phase, and a W phase connected in parallel to each other, and a plurality of unit conversions connected in series (cascade) in each phase A storage battery device 2 connected to the DC side of each unit converter cell 1, and a converter control device 10. Note that the number N of unit converter cells 1 connected in series in each phase may be two or more, and a case where N = 6 will be described below as an example.

  In this embodiment, the U phase has six unit converter cells 1U1 to 1U6 and storage battery devices 2U1 to 2U6. Unit converter cells 1U1 to 1U6 are connected in series on the AC side. Storage battery devices 2U1-2U6 are connected to the DC side of unit converter cells 1U1-1U6, respectively. Similarly, the V phase has six unit converter cells 1V1 to 1V6 and storage battery devices 2V1 to 2V6. The unit converter cells 1V1 to 1V6 are connected in series on the AC side. Storage battery devices 2V1 to 2V6 are connected to the DC side of unit converter cells 1V1 to 1V6, respectively. The W phase has six unit converter cells 1W1 to 1W6 and storage battery devices 2W1 to 2W6. Unit converter cells 1W1 to 1W6 are connected in series on the AC side. Storage battery devices 2W1 to 2W6 are connected to the DC side of unit converter cells 1W1 to 1W6, respectively.

  The converter control device 10 controls the unit converter cell 1. The converter control device 10 outputs a gate signal for switching the electrical connection of the switching elements of the plurality of unit converter cells 1.

  FIG. 2 is a diagram schematically illustrating a configuration example of the unit converter cell 1 and the storage battery device 2 of the power conversion device illustrated in FIG. 1.

  The unit converter cell 1 is a full bridge circuit including, for example, a self-excited switching element. The unit converter cell 1 includes a switching element such as an IGBT (Insulated Gate Bipolar Transistor) or a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) connected with an anti-parallel diode, and a smoothing capacitor 1C. These switching elements switch electrical connections according to a control signal from the converter control device 10.

  The storage battery device 2 includes an assembled battery BT, a battery monitoring circuit 21, and a battery management device (BMU: Battery Management Unit) 22.

  The assembled battery BT has a plurality of secondary battery cells 01 to 0m. The secondary battery cells 01 to 0m are, for example, lithium ion batteries. The secondary battery cells 01 to 0m (m is a positive integer) are not limited to lithium ion batteries, and nickel hydride storage batteries, lead storage batteries, nickel / cadmium storage batteries, and the like can also be used.

  The battery monitoring circuit 21 includes a voltage detection circuit that detects a voltage of the secondary battery cells 01 to 0m, a current detection circuit that detects a charging current and a discharging current of the assembled battery BT, and a temperature of at least one location of the assembled battery BT. And a temperature detection circuit for detection. The voltage detection circuit, the current detection circuit, and the temperature detection circuit output the periodically detected voltage, current, and temperature values to the battery management device 22.

  The battery management device 22 calculates the state of charge (SOC) of the assembled battery BT from the voltage, current, and temperature values received from the battery monitoring circuit 21. For example, the battery management device 22 calculates the SOC of the assembled battery BT by integrating the charging current and the discharging current of the assembled battery BT, and transmits the calculated SOC to the converter control device 10. In addition, the battery management device 22 monitors the voltage of the secondary battery cells 01 to 0m, determines whether the assembled battery BT is fully discharged and whether it is fully charged, and completes or fully discharges. It is transmitted to the converter control apparatus 10 that it is charge.

FIG. 3 is a diagram for explaining another configuration example of the assembled battery BT.
In this example, the assembled battery BT includes m units of k secondary battery cells connected in parallel (unit cell parallel-series configuration). When k × m secondary battery cells 011 to 0mk are connected in this way, the capacity of the assembled battery BT can be increased as compared with the case shown in FIG.

FIG. 4 is a diagram for explaining another configuration example of the assembled battery BT.
In this example, the assembled battery BT includes m units of m secondary battery cells connected in series and connected in parallel (unit cell series-parallel configuration). When k × m secondary battery cells 011 to 0 km are connected in this manner, the capacity of the assembled battery BT can be made larger than that shown in FIG.

  FIG. 5 is a block diagram illustrating a configuration example of the converter control device 10 of the power conversion device according to the present embodiment.

  The converter control device 10 includes a current command conversion unit 101, a 3-phase-dq current conversion unit 102, a current control unit 103, a 3-phase-dq voltage conversion unit 104, a dq-3 phase conversion unit 105, a gate A signal generation unit 106.

The current command conversion unit 101 determines the d-axis current command value id ^* on the dq coordinate and the q-axis current command value from the active power command value P ^* and the reactive power command value Q ^* received from the host controller. iq ^* .
id ^* = P ^* / Vd
iq ^* = Q ^* / Vd = 0
Here, Vd is a d-axis component of the system voltage V.

  The three-phase-dq current converter 102 receives the U-phase current Iu, the V-phase current Iv, and the W-phase current Iw, and from these values, the d-axis current component Id on the dq coordinate and the q-axis The current component Iq is converted and output to the current control unit 103.

The current control unit 103 calculates a difference between the d-axis current command value id ^* and the d-axis component Id and a difference between the q-axis current command value iq ^* and the q-axis component Iq, and performs proportional integral (PI) control. A d-axis component and a q-axis component of the voltage control value at which the difference is zero are output.

  The three-phase-dq voltage converter 104 receives the U-phase voltage Vu, the V-phase voltage Iv, and the W-phase voltage Vw, and from these values, the d-axis voltage component Vd on the dq coordinate and the q-axis It converts into voltage component Vq and outputs.

The d-axis voltage component Vd and the d-axis component of the voltage control value output from the current control unit 103 are input to the differentiator, and the d-axis voltage command Vd ^* is calculated. The q-axis voltage component Vq and the q-axis component of the voltage control value output from the current control unit 103 are input to the differentiator, and the q-axis voltage command Vq ^* is calculated.

The dq-3 phase conversion unit 105 receives the d axis voltage command Vd ^* and the q axis voltage command Vq ^* , performs reverse dq conversion, and performs voltage command values for each phase, that is, U phase voltage commands VuP, V The phase voltage command VvP and the W phase voltage command VwP are output.

  The gate signal generation unit 106 includes a U-phase voltage command VuP, a V-phase voltage command VvP, a W-phase voltage command VwP, an SOC of each assembled battery BT (SOCu1, SOCu2,... SOCwN,), a d-axis current component Id, and q The shaft current component Iq is received.

The gate signal generation unit 106 performs SOC balance control for equalizing the SOC of each assembled battery BT, and corrects the gate signal to calculate the capacity of the storage battery of the assembled battery BT.

  FIG. 6 is a block diagram illustrating a configuration example of the gate signal generation unit 106 shown in FIG. The gate signal generation unit 106 includes an interphase SOC balance control unit 1061, an interstage SOC balance control unit 1062, and a gate signal correction unit 1063.

  The inter-phase SOC balance control unit 1061 and the inter-stage SOC balance control unit 1062 intentionally slightly change the charging / discharging power of the assembled battery, thereby suppressing SOC non-uniformity due to element variations and errors. Means. This is because when the SOC non-uniformity increases, one assembled battery BT may reach full charge or complete discharge earlier than the others, and in this case, other assembled batteries BT can still be charged or discharged. This is because charging or discharging of all the assembled batteries BT is stopped regardless.

  The inter-phase SOC balance control unit 1061 receives the SOC (SOCu1, SOCu2... SOCwN), the d-axis current component Id, and the q-axis current component Iq of the assembled battery BT.

  The inter-phase SOC balance control unit 1061 calculates the average SOC (SOCu, SOCv, SOCw) of each phase and the average SOC (SOCave) of all the assembled batteries BT, and causes the average SOC of each phase to follow the SOCave. Here, the average SOC of each phase is the average SOC of N assembled batteries BT of each phase. For example, the average SOCu of the U phase is (SOCu1 + SOCu2 +... + SOCuN) / N. The average SOC (SOCave) of all the assembled batteries BT is (SOCu + SOCv + SOCw) / 3.

  The inter-phase SOC balance control unit 1061 calculates the difference between the average SOC (SOCu1, SOCu2... SOCwN) of each phase and SOCave, and based on this difference, the U-phase voltage command VuP, the V-phase voltage command VvP, and the W-phase voltage A value for adjusting the command VwP is calculated. At this time, the inter-phase SOC balance control unit 1061 prevents the total power of all phases from changing so as not to affect the system current.

  The output of the interphase SOC balance control unit 1061 is added to the voltage command values VuP, VvP, and VwP of each phase, and the voltage command value of each unit converter cell 1 is calculated by multiplying by 1 / N.

  The interstage SOC balance control unit 1062 causes the SOC of each assembled battery BT to follow each phase average SOC (SOCu, SOCv, SOCw) of that phase. By combining the interphase balance control and the interstage balance control, the SOCs of all the assembled batteries BT can be equalized.

  The interstage SOC balance control unit 1062 receives the SOC (SOCu1, SOCu2,... SOCwN) of the assembled battery BT and calculates the average SOC (SOCu, SOCv, SOCw) of each phase. The interstage SOC balance control unit 1062 calculates a value for adjusting the voltage command value of the unit converter cell 1.

  The output of the interstage SOC balance control unit 1062 and the output of the 1 / N device are added and input to the gate signal correction unit 1063.

  The gate signal correction unit 1063 generates a gate signal from the input voltage command value of the unit converter cell 1.

  FIG. 7 is a diagram for explaining an example of an operation of generating a voltage command value from the voltage command value in the gate signal correction unit 1063. FIG. 7 shows an example of the relationship between the voltage command value, the carrier wave of the six-stage unit converter cell 1 of each phase, the gate signal of the unit converter cell 1, and the phase voltage.

  The gate signal correction unit 1063 receives the voltage command value of the unit converter cell 1 and generates a gate signal using the carrier wave corresponding to each unit converter cell 1. Specifically, the gate signal correction unit 1063 generates a remarkable carrier wave by shifting the phase, and generates a gate signal by comparison with the voltage command. The semiconductor switch of the unit converter cell is turned on / off by a gate signal.

  In FIG. 7, for example, one curve is shown as the U-phase voltage command value. In addition, since the curve of a voltage command value is produced | generated also about the V phase and W phase which are other three-phase alternating currents, the curve of three voltage command values exists in total in three-phase alternating current. In addition, FIG. 7 shows an example of a unit conversion cell of six stages, and each gate signal of each stage is indicated by a triangular wave at the top of the figure.

  At this time, when calculating the battery capacity of the assembled battery BT, the gate signal correcting unit 1063 selects the assembled battery BT for calculating the battery capacity, and converts the output power of the assembled battery BT. Correct the voltage command value. Hereinafter, the correction operation of the voltage command value will be described.

  FIG. 8 is a flowchart for explaining an example of a method for generating a gate signal to the unit converter cell in the power conversion device of the first embodiment.

  After the voltage command calculation, the gate signal correction unit 1063 determines whether to calculate the actual capacity of the assembled battery BT (step SA1). When the actual capacities of a plurality of assembled batteries BT are regularly calculated sequentially, for example, it is determined that the practical amount of the assembled batteries BT is calculated when the value of the counter exceeds a predetermined value.

  When it is determined that the practical amount of the assembled battery BT is not calculated, the gate signal correction unit 1063 generates a gate signal without correcting the received voltage command value (correction value = 0).

  When it is determined that the actual capacity of the assembled battery BT is calculated, the gate signal correction unit 1063 selects the unit converter cell 1 corresponding to the assembled battery BT for which the practical amount is calculated (step SA2). Here, the U-phase N-stage unit converter cell 1uN will be described as the selected target unit converter cell.

  Subsequently, the gate signal correction unit 1063 sets the correction value VuPP-N for the voltage command value of the target unit converter cell 1uN to a preset value (step SA3). The gate signal correction unit 1063 corrects the voltage command value of the target unit converter cell 1uN with the correction value, and generates a gate signal using the corrected voltage command value (step SA4). At this time, the gate signal correction unit 1063 generates a gate signal with a voltage command value other than the target unit converter cell 1uN set to a correction value of zero, or generates a gate signal using a voltage command value that is not corrected.

FIG. 9 is a diagram for explaining an example of a method for calculating the actual capacity of the assembled battery.
When calculating the actual capacity of the assembled battery BT, first, the assembled battery BT for calculating the actual capacity is discharged until the voltage reaches the end-of-discharge voltage, and the converter control device 10 sets the discharge power state at this time to 0 Wh. And the SOC is set to 0% (timing A). If there is an error in the discharge power value at this time, the value is corrected.

  Subsequently, the assembled battery BT is charged with a constant power and charged until the voltage reaches the end-of-charge voltage. At that time, the converter control device 10 integrates the charging power of the assembled battery BT and calculates the charging power amount [Wh] (timing B). The integrated power value when the end-of-charge voltage is reached is defined as the charge capacity. At this time, if there is an error between the charge capacity held inside and the calculated charge capacity, the latest integrated value is set as the charge capacity.

  Subsequently, the assembled battery BT is discharged at a constant power at a rated power, and is discharged again until the voltage reaches a discharge end voltage (timing C). At that time, the converter control device 10 monitors the voltage and current of the battery pack BT, integrates the discharge power of the battery pack BT, and calculates the discharge power amount [Wh]. The integrated power value at the time when the end-of-discharge voltage is reached is defined as the discharge capacity. At this time, if there is an error between the discharge capacity held inside and the calculated discharge capacity, the latest integrated value is set as the discharge capacity. Subsequently, the selected assembled battery BT is charged so as to be uniform with the capacity of the other assembled battery BT.

  Therefore, the voltage command value is corrected so that the assembled battery BT is discharged first, and after the voltage of the selected assembled battery BT becomes the end-of-discharge voltage, the voltage command value is corrected so as to charge the assembled battery BT, After the voltage of the selected assembled battery BT reaches the end-of-charge voltage, the correction value VuPP-N is set so that the voltage command value is corrected so that the assembled battery BT is discharged again. Thus, in order to set the correction value VuPP-N, the gate signal correction unit 1063 may receive the voltage value of the assembled battery BT and switch the correction value VuPP-N.

  The gate signal correction unit 1063 corrects the voltage command value by adding the correction value VuPP-N to the voltage command value of the target unit converter cell 1uN, and generates a gate signal by comparing with the carrier wave. The voltage command value of the other unit converter cell 1 is not corrected (corrected value is zero), and is compared with the carrier wave to generate a gate signal.

  When the target unit converter cell 1uN is controlled by the gate signal generated from the voltage command value corrected in this way, and the other unit converter cell 1 is controlled by the gate signal generated from the voltage command value not corrected, the selected assembled battery It is possible to calculate the actual capacity for BT. That is, the other assembled batteries BT are controlled so that the SOC is equalized by the SOC balance control, but the selected assembled battery BT is charged from a fully discharged state to a fully charged state, and then completely discharged again. It becomes.

  As a result, the converter control device 10 calculates the charge electric energy and the discharge electric energy of the assembled battery BT by integrating the charging / discharging current of the selected assembled battery BT, and the deterioration of the assembled battery BT from these values. Degree can be judged.

  Similarly, the gate signal correction unit 1063 corrects the voltage command value of the unit converter cell 1 for the other assembled batteries BT to calculate the charging power amount and the discharging power amount, and all the assembled batteries BT The degree of deterioration can be determined sequentially. Therefore, the converter control device 10 can perform control according to the degree of deterioration for each assembled battery BT, and the power conversion device frequently stops due to complete discharge or full charge of one assembled battery BT, It is possible to avoid a decrease in output power.

  As described above, according to the present embodiment, it is possible to provide a highly reliable power converter and a method for controlling the power converter.

  Next, the power converter of 2nd Embodiment and the control method of a power converter are demonstrated with reference to drawings. In the following description, the same components as those in the first embodiment described above are denoted by the same reference numerals and description thereof is omitted.

In the present embodiment, the operation of the gate signal correction unit 1063 receiving the active power command P ^* from the host control device and the operation of setting the correction value of the voltage command value in the gate signal correction unit 1063 are described in the first embodiment. Is different.

  FIG. 10 is a flowchart for explaining an example of a method for generating a gate signal to the unit converter cell in the power conversion device of the present embodiment.

  After the voltage command calculation, the gate signal correction unit 1063 determines whether to calculate the actual capacity of the assembled battery BT (step SB1). Similarly to the first embodiment described above, when the actual capacity of a plurality of assembled batteries BT is sequentially calculated periodically, for example, when the counter value exceeds a predetermined value, the practical amount of the predetermined assembled battery BT is calculated. to decide.

  When it is determined that the practical amount of the assembled battery BT is not calculated, the gate signal correction unit 1063 generates a gate signal without correcting the received voltage command value (correction value = 0).

  When it is determined that the actual capacity of the assembled battery BT is calculated, the gate signal correction unit 1063 selects the unit converter cell 1 corresponding to the assembled battery BT for which the practical amount is calculated (step SB2). Here, the U-phase N-stage unit converter cell 1uN will be described as the selected target unit converter cell.

Subsequently, the gate signal correction unit 1063 determines whether or not the active power command P ^* is greater than zero (step SB3). The gate signal correction unit 1063 receives the active power command P ^* from the host control device.

When the power command P ^* is input (P ^* ≦ 0), the gate signal correction unit 1063 sets the target battery pack BT to complete discharge or full charge before other battery packs BT. The command value correction amount VuPp−N> 0 is set (step SB4). If the output P ^* ≧ 0, the voltage command value correction amount VuPp−N ≦ 0 is set (step SB5). The correction amount VuPp-N is a fixed value set by parameter setting or the like.

  The gate signal correction unit 1063 generates a gate signal of the target unit converter cell 1uN using the corrected voltage command value (step SB6). At this time, the gate signal correction unit 1063 generates a gate signal with a voltage command value other than the target unit converter cell 1uN set to a correction value of zero, or generates a gate signal using a voltage command value that is not corrected.

  When the voltage command value is corrected as described above, when charging / discharging the power converter, only the target battery pack BT can be completely discharged or fully charged, and the battery capacity of the target battery pack BT is set. Can be calculated.

  Further, when the voltage command value is corrected as described above, when charging a plurality of assembled batteries BT in the power conversion device, the charge amount of the target assembled battery BT becomes larger than that of the other assembled batteries BT, When discharging a plurality of assembled batteries BT in the conversion device, the discharge amount of the target assembled battery BT is larger than that of the other assembled batteries BT. Therefore, the time required for the actual capacity of the target assembled battery BT can be shortened.

  That is, according to the power conversion device and the power conversion device control method of the present embodiment, it is possible to provide a highly reliable power conversion device and a power conversion device control method as in the first embodiment.

  Next, the power converter of 3rd Embodiment and the control method of a power converter are demonstrated with reference to drawings.

  FIG. 11 is a block diagram illustrating a configuration example of the gate signal generation unit 106 of the power conversion device according to the present embodiment.

  In the present embodiment, the gate signal generation unit 106 further includes an inversion unit 1064 disposed in the previous stage of the gate signal correction unit 1063.

  The inversion unit 1064 receives the voltage command value to the unit converter cell, sets the voltage command value to the target unit converter cell in reverse phase, and outputs the other voltage command value to the gate signal correction unit 1063 as it is.

  The gate signal correction unit 1063 receives the voltage command value from the inversion unit 1064, and multiplies the voltage command value of another unit converter cell in phase with the target unit converter cell by (N + 1) / (N-1) to generate a voltage. The command value is corrected, and a gate signal is generated using the corrected voltage command value.

  FIG. 12 is a diagram for explaining an example of an operation for generating a voltage command value from a voltage command value in the power conversion device of the present embodiment. FIG. 12 shows an example of the relationship between the voltage command value, the carrier wave of the six-stage unit converter cell 1 of each phase, the gate signal of the unit converter cell 1, and the phase voltage.

  Similarly to the first embodiment, the gate signal correction unit 1063 generates a remarkable carrier wave by shifting the phase, and generates a gate signal by comparison with a voltage command. Here, the gate signal correction unit 1063 generates a gate signal using the corrected voltage command value. That is, the voltage command value of the target unit converter cell (the sixth stage in FIG. 12) is in reverse phase. In addition to the target unit converter cell, a gate signal is generated using a voltage command value corrected by multiplying by a coefficient of (N + 1) / (N-1).

  In FIG. 12, one curve is shown as the voltage command value other than the target unit converter cell, but the voltage command value is adjusted for a plurality of unit converter cells 1 in each phase by interstage SOC balance control. In this case, the voltage command value is the number of stages in each phase.

  In the power conversion device of the present embodiment, since the voltage command value before correction is generated so as to make the SOC of the plurality of assembled batteries BT uniform, the gate signal to the target unit converter cell is reversed as described above. In the phase, the difference between the SOC of the target assembled battery BT and the average value of the SOC gradually increases, and complete discharge or full charge can be achieved individually.

  FIG. 13 is a flowchart for explaining an example of a method for generating a gate signal to a unit converter cell in the power conversion device of this embodiment.

  After the voltage command calculation, the gate signal generation unit 106 determines whether or not to calculate the actual capacity of the assembled battery BT (step SC1). Similarly to the first embodiment described above, when the actual capacity of a plurality of assembled batteries BT is sequentially calculated periodically, for example, when the counter value exceeds a predetermined value, the practical amount of the predetermined assembled battery BT is calculated. to decide.

  When it is determined that the practical amount of the assembled battery BT is not calculated, the gate signal generation unit 106 generates a gate signal without correcting the received voltage command value.

  When it is determined that the actual capacity of the assembled battery BT is calculated, the gate signal generation unit 106 selects the unit converter cell 1 corresponding to the assembled battery BT for which the practical amount is calculated (step SC2). Here, the U-phase N-stage unit converter cell 1uN will be described as the selected target unit converter cell.

  Subsequently, the gate signal generation unit 106 reverses the voltage command value VuP-N of the target unit converter cell 1uN in the inversion unit 1064 (step SC3), and in the gate signal correction unit 1063, The voltage command value of the other target unit converter cell is multiplied by (N + 1) / (N-1) (step SC4).

  The gate signal generation unit 106 generates a gate signal using the voltage command value corrected as described above (step SC5). At this time, for the phase not including the target assembled battery BT, the gate signal generation unit 105 generates a gate signal by setting the correction value of the voltage command value to zero, or generates a gate signal using a voltage command value that is not corrected. To do.

  When the voltage command value is corrected as described above, when charging / discharging the power conversion device, only the assembled battery BT targeted individually can be completely discharged or fully charged without changing the phase energy. The battery capacity of the assembled battery BT can be calculated.

  That is, according to the power conversion device and the power conversion device control method of the present embodiment, it is possible to provide a highly reliable power conversion device and a power conversion device control method as in the first embodiment.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  BT ... assembled battery, 1 ... unit converter cell, 1U1-1U6 ... unit converter cell (U phase), 1V1-1V6 ... unit converter cell (V phase), 1W1-1W6 ... unit converter cell (W phase) DESCRIPTION OF SYMBOLS 2 ... Storage battery device, 2U1-2U6 ... Storage battery device (U phase), 2V1-2V6 ... Storage battery device (V phase), 2W1-2W6 ... Storage battery device (W phase), 10 ... Converter control device, 106 ... Gate signal Generation unit, 1061... Inter-phase SOC balance control unit, 1062... Interstage SOC balance control unit, 1063... Gate signal correction unit, 1064.

Claims (7)

A plurality of unit converter cells having a semiconductor switch for switching the connection between the AC side and the DC side, the AC side being connected in cascade,
A storage battery device including an assembled battery connected to the DC side of the unit converter cell;
An SOC balance control unit that generates a voltage command value for PWM control so that the remaining energy of the assembled battery is equalized, and when measuring the battery capacity of the assembled battery individually, setting a target assembled battery, A gate that corrects a voltage command value by adding a preset correction value to the voltage command value of the unit converter cell for the target assembled battery, and generates a gate signal of the semiconductor switch using the corrected voltage command value power conversion device and a transducer controller having a signal correction unit. The gate signal correcting unit is configured as a positive value of the correction value when charging the power converter, the power converter according to claim 1, wherein a negative value of the correction value when discharging the power converter. A plurality of unit converter cells having a semiconductor switch for switching the connection between the AC side and the DC side, the AC side being connected in cascade,
A storage battery device including an assembled battery connected to the DC side of the unit converter cell;
An SOC balance control unit that generates a voltage command value for PWM control so that the remaining energy of the assembled battery is equalized;
When individually measuring the battery capacity of the assembled battery, a target assembled battery is set, an inversion unit that reverses the voltage command value of the unit converter cell with respect to the target assembled battery, and N is the target assembled battery the unit converter when the number of stages of the cell to the voltage command value of the target assembled battery and other of said unit converters cell phase (N + 1) / (N -1) is multiplied by the correction contained in phase with, power conversion device and a transducer controller with a gate signal correction unit, a generating a gate signal of the semiconductor switch with a voltage command value after correction.   The power converter device of any one of Claim 1 thru | or 3 provided with the phase where the said unit converter cell was cascade-connected. A plurality of unit converter cells having a semiconductor switch for switching the connection between the AC side and the DC side, the AC side being connected in cascade,
A storage battery device including an assembled battery connected to the DC side of the unit converter cell, and a control method of a power converter comprising:
Generate a voltage command value for PWM control so that the remaining energy of the assembled battery is equal,
Determine whether to measure the battery capacity of the assembled battery individually,
When measuring the battery capacity of the assembled battery individually, set the target assembled battery,
Correct the voltage command value by adding a preset correction value to the voltage command value of the unit converter cell for the target assembled battery,
Generating a gate signal of the semiconductor switch using the corrected voltage command value ;
Control method of power converter. 6. The power according to claim 5, wherein in the step of correcting the voltage command value, the correction value is a positive value when charging the power conversion device, and the correction value is a negative value when discharging the power conversion device. Control method of conversion device. A plurality of unit converter cells having a semiconductor switch for switching the connection between the AC side and the DC side, the AC side being connected in cascade,
A storage battery device including an assembled battery connected to the DC side of the unit converter cell, and a control method for a power conversion device comprising:
Generate a voltage command value for PWM control so that the remaining energy of the assembled battery is equal,
Determine whether to measure the battery capacity of the assembled battery individually,
When measuring the battery capacity of the assembled battery individually, set the target assembled battery,
An inversion unit that reverses the voltage command value of the unit converter cell with respect to the target assembled battery, and the target assembled battery when N is the number of stages of the unit converter cell included in the same phase as the target assembled battery a voltage command value of the other of said unit converters cell-phase multiplied by the (N + 1) / (N -1) is corrected,
Generating a gate signal of the semiconductor switch using the corrected voltage command value ;
Control method of power converter.

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