JP2002034158A - Power converter control device for power storage device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power converter control device for a power storage device, capable of easily corresponding to a condition in the area of use to provide high general purpose usability. SOLUTION: A power converter 4 is arranged between a battery 2 (power storage means) and a power system 3. The power converter 4 is controlled by a power converter control device 6. The power converter control device 6 is provided with a plurality of operating mode execution means 7 to 15 for generating a control command for executing a plurality of operating modes, an operating mode selecting output means 17 for selectively outputting the output of a plurality of the operating mode execution means 7 to 15 assigned by a mode designating means 16, and a drive signal generating means 19 for generating a drive signal based on the control command selected by the operating mode selecting output means 17 to be output from one or more operating mode execution means.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device used for a power converter for a power storage device installed in a power system, and more particularly to a control device for leveling loads and improving power quality. The present invention relates to a power converter control device for a power storage device.

[0002]

2. Description of the Related Art With the recent increase in power demand, the power difference between daytime and nighttime or between seasons tends to increase. This power difference causes a decrease in the utilization factor of the power generation equipment and the power transmission equipment, and hinders efficient operation of the equipment. As one method of solving this, a power storage device combining a battery and an inverter has been proposed, and its effectiveness is currently being verified. Most of the power storage devices currently used mainly occupy a so-called active power control function of storing power at night and supplying power to the system during daytime. On the other hand, maintaining the power quality of the system at a certain level is also an important issue in system operation, and the reactive power control using the phase adjustment equipment plays a role. As an example of power quality management, reactive power control using SVC or SVG is widely used for voltage compensation, and an active filter or the like is separately installed for harmonic suppression. However, many of these compensators have only one function, and at present, almost no inverters that integrate a power storage function and a power quality improvement function have been developed so far. By integrating these functions, one compensating device that has been separately installed can be reduced to one, and space saving can be achieved.

As this type of power storage device, Japanese Patent Application Laid-Open No.
-65588. This conventional power storage device operates so as to always realize both load leveling and power quality stabilization.

[0004]

The power storage devices proposed in the prior art are designed in accordance with the power demand and power quality in the area where the power storage apparatus is used, so that the versatility is poor and the power storage apparatus is not used in the area where the power storage apparatus is used. When the power demand situation or the power quality situation has changed, there has been a problem that it is not possible to quickly respond to the change.

It is an object of the present invention to provide a power converter control device for a power storage device used in a power converter for a power storage device having high versatility and capable of easily responding to the situation in a use area.

[0006]

According to the present invention, there is provided a power converter control device for a power storage device, which is arranged between a power storage device for storing power and a power system and the power storage device. Power conversion for a power storage device that converts AC power from a power system into DC power, charges DC power storage means with DC power, converts DC power stored in the power storage means into AC power, and supplies the AC power to the power system. , Power system state detecting means for detecting the state of the power system, and at least one of the active power and the reactive power output from the power converter for the power storage device, to control the load leveling and power of the power system. In order to realize at least one of the quality improvement of the power storage device, a drive signal for driving the power converter for the power storage device is generated in accordance with the detection output of the power system state detection means and a plurality of predetermined operation modes. ; And a that the power converter controller.

In the present invention, the power converter control device includes a plurality of operation mode executing means for generating control commands for executing the plurality of operation modes, and a plurality of operation modes designated in advance by external operations or the like. An operation mode selection output means for selecting and outputting an output of the mode execution means, and a drive signal for generating a drive signal based on a control command selected by the operation mode selection output means and output from one or more operation mode execution means. Generating means. When such a configuration is employed, the state of the power system in the area where the power storage device is used can be obtained from a plurality of operation mode execution means predetermined in order to achieve at least one of load leveling and power quality improvement of the power system. The operation mode required for leveling the load and / or improving the quality of the power can be arbitrarily selected and designated by an external operation in accordance with the requirements, so that it is possible to easily obtain a power storage device suitable for the use area. This makes it possible to increase the versatility and quickly respond to changes in the power situation in the use area.

No matter how large the capacity of the power storage means is, there is a limit to the increase in the capacity. Therefore, the capacity of the power storage means is used as efficiently as possible to achieve load leveling and improvement of power quality. It is preferable to operate the power storage means in such a manner. There is a difference between the operation modes executed by the plurality of operation mode execution means in the effects obtained by executing the operation modes. For this reason, prioritizing the operation modes executed by the plurality of operation mode execution means in advance and executing the specific operation mode execution means with priority in a specific situation makes it possible to maximize the capacity of the power storage means. This makes it possible to achieve load leveling and power quality improvement. Therefore, in order to realize this, when two or more operation mode execution units are selected from among the plurality of operation mode execution units, one of the predetermined high-priority priority units is selected.
When the above operation mode execution means is selected and the output is output from the one or more operation mode execution means having the higher priority, the output of the selected operation mode execution means having the other lower priority is driven. The operation mode selection means may be configured to select the outputs of the plurality of operation mode execution means so as not to output the signal to the signal generation means.

The plurality of operation mode execution means include a constant power charge / discharge operation mode execution means for controlling active power for leveling the load, a pattern operation mode execution means, and a load following operation mode. One operation mode execution means selected from the execution means, a power fluctuation suppression operation mode execution means for controlling active power for improving power quality, and a voltage fluctuation suppression operation for controlling reactive power for improving power quality. It is preferable to include at least one of a mode execution unit, a sag suppression operation mode execution unit, a voltage imbalance suppression operation mode execution unit, a flicker suppression operation mode execution unit, and a harmonic suppression operation mode execution unit. At the present time, the versatility is highest when all the operation mode execution means are included. However, when implementing the present invention, it is not necessary to include all the operation mode execution means.

When such a specific operation mode execution means is used, the power fluctuation suppression operation mode execution means, the instantaneous sag suppression operation mode execution means and the flicker suppression operation mode execution means are assigned higher priority. Preferably, there is at least one operation mode executing means. When the priorities are determined in this manner, the power of the power storage means can be concentrated on the execution of the operation mode with a high effect, and the leveling of the load and the quality of the power can be more effectively improved.

Even when the operation modes are prioritized as described above, from the viewpoint of the execution effect, the priorities of the power fluctuation suppression operation mode execution means and the instantaneous sag suppression operation mode execution means are changed to the flicker suppression operation mode. Preferably it is higher than the execution means.

[0012]

Embodiments of the present invention will be described below. In order to facilitate understanding of embodiments of the present invention, while describing the results of development performed to invent a power converter control device for a power storage device of the present invention,
An embodiment of the present invention will also be described. The development was conducted under the guidance of Akira Oyama and Katsu Utsunomiya of Kyushu Transformer Co., Ltd., and simulations were requested from Masatoshi Nakahara and Kosuke Harada of Sojo University. Hereinafter, a 100 kW class multifunctional inverter device combining a power storage function and a power quality improvement function (a generic name including a power converter for a power storage device and a power converter control device used in the description of an embodiment below, The development of a multifunctional inverter device) and its control method will be described. This multifunctional inverter device has four active power control functions and five reactive power control functions (functions corresponding to a plurality of operation mode execution means used in the description of the embodiment below), and combines these functions. It is configured so that it can be used. In a specific example, three-phase / dq-axis coordinate conversion is used to separate target frequency components for the purpose of simultaneously controlling active power and reactive power. In addition, the parameters of the actual machine controller are adjusted smoothly, and system disturbances such as flicker and harmonics, which are difficult in actual machine experiments, can be easily generated. planned. Finally, the effectiveness of the multifunctional inverter was verified by an experiment using a 100 kW multifunctional inverter device.

This multi-function inverter device has a power storage function as a constant power charge / discharge, a pattern operation, and a load following function, as well as a power quality improvement function such as voltage fluctuation suppression, voltage sag suppression, voltage imbalance suppression, and flicker suppression. It has nine functions (operation mode execution means) of harmonic suppression and power fluctuation suppression. Each of these functions can be divided into a normal operation function and a standby operation function, and these can be used in combination.

[Configuration of Multifunctional Inverter Apparatus] FIG. 1 shows the configuration of the test circuit, and Table 1 shows the specifications of the inverter.

[0015]

[Table 1] This test circuit includes an inverter (power converter), a power supply, a line impedance, a load, and a disturbance generator. Note that a power converter control device for driving and controlling an inverter (power converter) is not shown. The inverter has an output capacity of 100 kVA, and as the power element, IGBTs rated at 1200 V and 1000 A are used in parallel with the upper and lower arms of each phase, and a current capacity of 4000 A is secured. Further, the PWM control of each power element is 2
An arm modulation method is used. This is the phase voltage eu, e
This is a method in which the third harmonic is superimposed on v and ew. This two-arm modulation method is a method of controlling the line voltage, and 1) can reduce the switching loss as compared with the triangular wave comparison method.
2) The maximum output voltage is about 15% compared to the triangular wave comparison method.
There is a feature that it can be enlarged.

This inverter is connected to a 660 through a low-pass filter for removing switching ripples and an interconnection transformer.
It is connected to the 0V system. The control unit (power converter control device) uses a 16-bit, 20 MHz, fixed-point arithmetic DSP, and calculates the compensation amount and PW
All-digital control for generating M signals is realized.

[Multi-function operation function] Table 2 shows the operation functions of the multi-function inverter device.

[0018]

[Table 2] As shown in the above table, the active power control function includes a constant power charging / discharging function of controlling input / output power from an inverter (power converter) to a constant value (in the description of the following embodiments,
A function executed by the constant power charge / discharge operation mode execution means), a pattern operation function of automatically operating according to a preset charge / discharge power value and an operation time in a preset pattern (pattern operation mode execution in the description of the embodiment below). (A function executed by the means), a load following function for causing the inverter output power (discharge power) to follow the load power according to the magnitude of the load power (the load following operation mode executing means executes the load following operation mode executing means in the description of the following embodiments). Function), a power fluctuation suppression function for the purpose of suppressing system fluctuations (suppressing steep fluctuations of the active power) by inputting / outputting active power from the inverter in accordance with fluctuations in the system frequency (power fluctuations will be described in the following embodiments). (A function executed by the suppression operation mode execution means). Also,
As the reactive power control function, a voltage fluctuation suppression function (arbitrarily controlling the reactive power so as to compensate for the fluctuation / decrease of the bus voltage) arbitrarily controlling the voltage at the interconnection point with the system (in the description of the embodiment below) A function executed by the voltage fluctuation suppressing operation mode executing means), a voltage sag suppressing function for suppressing an instantaneous voltage drop of about 0.07 to 1.0 second (the voltage sag suppressing operation mode execution in the description of the embodiment below). A function executed by the means), a voltage unbalance suppression function for suppressing the unbalance of the bus voltage by controlling the reactive power individually for each phase (in the description of the embodiment below, the voltage unbalance suppression operation mode execution means Function to be executed), and a flicker suppression function for compensating for a flicker voltage of 10 Hz (in the following description of the embodiment,
Function executed by the voltage imbalance suppression operation mode executing means),
There is a harmonic suppression function of analyzing the harmonics of the load current and outputting a current in the same phase and opposite direction to each component (a function executed by the harmonic suppression operation mode execution means in the description of the embodiment below). .

As the selection of the operation function, one can be selected from the common functions of the active power control and a plurality of selections can be made from the common functions of the reactive power control. Further, a plurality of standby functions for active power control and reactive power control can be selected. However, if the sag suppression function and the flicker suppression function operate simultaneously,
The sag suppression function is given priority. Note that the standby function and the regular function are defined as follows.

Standby function: A function that is activated only when the event occurs in the system, and automatically stops after the event is removed. When the standby function is activated, all the normal functions are stopped and the entire capacity of the inverter is allocated to the standby function.

Regular function: A function that is always activated when selected, regardless of whether or not the event has occurred.

[Control system design of power converter control device] In order to realize each of the above-mentioned operation functions, three-phase alternating current is coordinate-converted to a two-axis rotating coordinate system rather than directly treating three-phase alternating current. Is easier to control if you control the amount of So first,
The conversion from the three-phase alternating current to the two-axis rotating coordinate system will be described. Next, by controlling which frequency component after the coordinate transformation,
It shows whether the driving function can be realized. FIG. 2 is a block diagram of the entire control system.

When converting the three-phase AC currents iu, iv, and iw into currents on a two-axis rotating coordinate system, three-phase / positive-phase dq-axis coordinate conversion that takes rotational coordinates in the same direction as phase rotation, and phase rotation A three-phase / negative-phase dq-axis coordinate transformation that takes rotation coordinates in the opposite direction is defined. Also, positive-phase dq-axis / 3-phase coordinate conversion which is an inverse conversion from the positive-phase dq-axis to three-phase AC, and negative-phase dq-axis / normal-phase dq-axis which is a conversion from the negative-phase dq-axis to the positive-phase dq-axis Coordinate transformations are also defined, which can be expressed as (1) to (4) below. However, iu, iv, and iw do not include the zero-phase current. Here, ipd and ipq are the d-axis and q-axis currents on the positive-phase dq axes, and iNd and iNq are the d-axis and q-axis currents on the negative-phase dq axes. The normal phase dq / 3-phase coordinate conversion matrix is the right inverse matrix of the three-phase / normal phase dq-axis coordinate conversion matrix.

[0024]

(Equation 1) The three-phase AC currents iu, iv, iw not including the zero-phase component are defined by the following equation (5). However, the first term on the right side of iu, iv, iw represents the positive phase component, and the second term on the right side represents the negative phase component.

[0025]

(Equation 2) Here, Ipn is the effective value of the positive-phase current, INn is the effective value of the negative-phase current, and φn and θn are the phase difference between the positive and negative phases of the nth harmonic. By substituting equation (5) into equations (1) and (2) and rearranging, the following equation is obtained.

[0026]

(Equation 3) However, a value with a horizontal line above ipd and ipq is ip
DC components of d and ipq, respectively,
Represents the fundamental reactive current. Also, ipd (2ω),
The value with a wavy line above ipq (2ω) is ipd, ip
The value of the 2ω component of q and the wavy line above ipd and ipq are the direct current of ipd and ipq and harmonic currents other than 2ω. Further, the value with a horizontal line above iNd, iNq is the DC component of iNd, iNq, and the reverse-phase current is iNd, iNq.
A value with a dashed line above d, iNq represents a harmonic current other than DC of iNd, iNq.

Here, in the constant power charging / discharging and load following of the inverter, the above-mentioned fundamental wave active current may be controlled to control the active power, and the active power corresponding to the difference from the reference frequency may be controlled even in the power fluctuation suppression. , So that the fundamental wave effective current is similarly controlled. In the voltage fluctuation suppression and the sag suppression, the reactive power is controlled to control the system voltage, and the fundamental wave reactive current is controlled. In the unbalance suppression, the negative phase current is suppressed. Further, in the flicker suppression, the fundamental current and the harmonic current are controlled, and in the harmonic suppression, the harmonic current is suppressed. Table 3 summarizes these.
By controlling each of the current components shown in Table 2, the operation functions shown in Table 2 can be realized.

[0028]

[Table 3] FIG. 2 shows an example of a specific control block. 3 and 4 are partially enlarged views of FIG. The control block is roughly divided into an active power / reactive power calculation unit A, a control unit B that extracts a current component shown in Table 3 and compares it with a target value to calculate a control amount, and a non-interference between active power and reactive power. It is composed of a PQ non-interference control section C for performing the conversion, a current feedback section D for overcurrent prevention, and a PWM signal generation section E. For example, in the constant power charging / discharging, the active power and the reactive power output from the inverter are compared with a target value, and a current command value is output from the PI controller according to each error so that the inverter low voltage side current follows the current command value. To do. An error between the current command value and the inverter low-voltage side current is converted into a voltage command value in the PQ non-interference part C, and is added to the interconnection point voltage as a voltage change.
Further, by performing the positive-phase dq-axis / 3-phase conversion, a three-phase voltage command value is obtained, and this three-phase voltage command value is converted into a PWM signal. The phase reference of the coordinate conversion is based on the U-phase voltage of the interconnection point, and the calculation of the active / reactive power of the inverter is performed based on the interconnection point phase voltage similarly calculated by converting the output current of the high-voltage side inverter into three-phase / positive-phase dq axes. Is multiplied by a line voltage obtained by performing a three-phase / positive-phase dq-axis coordinate conversion. This makes it possible to calculate the active / reactive power for each sample point. In these figures, the selection / non-selection switch is turned on when each function is selected, and the compensation amount from the non-selected function is zero when the function is not selected. Furthermore, as for the standby function, the compensation amount is set to zero only by selecting the standby function, and the switch is switched from standby to operation only when the event occurs, thereby suppressing the occurrence event.

FIG. 5 is a block diagram schematically showing the configuration of an embodiment of the power converter control device for a power storage device according to the present invention, using the example of FIG. In FIG. 5, the power storage device 1 includes a storage battery 2 serving as a power storage unit for storing power.
And a power source disposed between the power system 3 and the storage battery 2 to convert AC power from the power system 3 into DC power, charge the storage battery 2 with the DC power, and convert the DC power stored in the storage battery 2 into AC power. The power converter includes a power converter for a power storage device that converts and supplies the converted power to a power system, a power system state detection unit that detects various states of the power system, and a power converter control device. The power converter control device 6 controls at least one of the active power and the reactive power output from the power converter 4 for the power storage device, and performs at least one of the leveling of the load of the power system 3 and the improvement of the power quality. A configuration for generating a drive signal for driving the power converter 4 for a power storage device in accordance with the detection output of the power system state detection means 5 and the outputs of a plurality of predetermined operation mode effecting means 7 to 15 for realization. have.

Specifically, the power converter control device 6
Nine operation mode execution means 7 to 15 for generating control commands for executing a plurality of operation modes, and a plurality of operation mode execution means (not shown in FIG. 2) operated by a mode designating means 16 (not shown in FIG. 2). Operation mode selection output means 17 (indicated by a switch symbol in FIG. 2) for selecting and outputting the output of the means, and output from one or more operation mode execution means selected by the operation mode selection output means 17 And a drive signal generating means 19 for generating a drive signal based on the control command added by the adder 18. As the nine operation mode execution means, specifically, a constant power charge / discharge operation mode execution means 7 for controlling active power for load leveling,
Pattern operation mode execution means 8, load following operation mode execution means 9, power fluctuation suppressing operation mode execution means 10 for controlling active power for improving power quality, and reactive power control for improving power quality A voltage fluctuation suppression operation mode executing means 11, a voltage imbalance suppression operation mode execution means 12, a voltage sag suppression operation mode execution means 13, a flicker suppression operation mode execution means 14, and a harmonic suppression operation mode execution means 15 are provided.

When such a configuration is adopted, the power system 3
A plurality of predetermined operation mode executing means 7 for realizing at least one of load leveling and power quality improvement.
From 15, the operation mode necessary for leveling the load and / or improving the quality of the electric power can be arbitrarily selected from the outside according to the state of the electric power system in the area where the electric power storage device is used.
Since it is possible to specify the power storage device, it is possible to easily obtain a power storage device adapted to the area of use. Further, by changing the selection of the operation mode effective means, it is possible to quickly respond to a change in the power situation in the use area.

The operation modes executed by the nine operation mode execution means 7 to 15 have different effects obtained by executing the operation modes. Therefore, in this example, the power fluctuation suppression operation mode execution means 10, the instantaneous sag suppression operation mode execution means 13, and the flicker suppression operation mode execution means 14 are replaced by operation mode execution means having a higher priority than other operation mode execution means. And When the priorities are determined in this manner, the power of the storage battery can be concentrated on the execution of the operation mode having a high effect, and the load leveling and the power quality can be more effectively improved.

Even when the priority is given to the operation mode execution means as described above, considering the execution effect,
It is preferable that the power fluctuation suppressing operation mode executing means 10 and the instantaneous sag suppressing operation mode executing means 13 have a higher priority than the flicker suppressing operation mode executing means 14.

The control system configuration shown in FIG. 2 and the embodiment shown in FIG. 5 demonstrate that the operation functions shown in Table 2 can be realized.
The results are shown by AT simulation and actual experiments of a 100 kW multifunctional inverter device. The SCA used this time
The T simulator has 3 phase / normal phase dq axis coordinate conversion, 3 phase /
A negative phase dq axis coordinate conversion, a positive phase dq axis / 3-phase coordinate conversion, a negative phase dq axis / positive phase dq axis coordinate conversion, and a frequency detection circuit are added. In addition, in order to verify the response in the case where no restriction is provided for each function in the simulation, the simulation was performed by modeling only the target driving function without providing the dead zone and the limiter in FIG.

FIG. 6 shows an SCAT simulation circuit for constant power charging / discharging when a control signal from the constant power charging / discharging operation mode execution means is used. However, in the actual machine, four IGBTs are used in parallel for each phase upper and lower arm, but here there is no variation in the four parallel IGBTs,
It is assumed that the IGBT is turned off, and the simulation circuit is represented by one IGBT. The main circuit is 3
Simple configuration of phase constant voltage power supply, line impedance and load. In the constant power charge and discharge, the active power output from the inverter (power converter) is made to follow a target value, and at the same time, by controlling the reactive power to zero, the constant active power is output from the inverter while maintaining the power factor at almost 1. It is a function.
FIGS. 7A and 7B show active power and reactive power responses of the inverter when constant power discharge is performed. FIG. 7A shows a simulation result, and FIG. 7B shows an experimental result. From this, 100
It can be seen that kW discharge and charge were realized. The output error of the inverter with respect to 100 kW of discharge and 100 kW of charge was 0.3
%, 0.6%, and in the experiment, the error was ± 1% or less with respect to the designed value ± 3%. Here, the active power response is not stepped, but from 0 kW to 100 kW or from 0 kW.
The reason why the slope is changed to 100 kW is to suppress sudden input / output of the battery current.

The result when the control signal from the power fluctuation suppressing operation mode executing means is used will be described.

The power fluctuation suppression is a function of detecting a fluctuation of the system frequency f and outputting an active power from the inverter according to a difference from the reference frequency fref (= 60). Give in.

Pref = KF (fref-f) where KF [kW / Hz] is a coefficient for converting frequency into active power, and KF = 30 [kW / Hz]. FIG. 8 shows the response when the system frequency was changed from 60 Hz to 59 Hz. FIGS. 8A and 8B show the simulation results, and FIG. 8C shows the experimental results. FIG. 8A shows that 30 kW of active power is output from the inverter when the system frequency is changed from 60 Hz to 59 Hz. FIGS. 8B and 8C show simulation results and experiment results of the interconnection point U-phase voltage and the inverter U-phase current. (B) From the simulation result in the figure, the peak value from the inverter is 35 immediately after the power fluctuation suppression function is started.
The current of A flows because the active power target value is added stepwise immediately after switching. In addition, it can be seen from the simulation and experimental results that the inverter output current is settled in about 4 to 5 cycles after the activation of the power fluctuation suppression function. However, since the power supply is not a generator model but a constant voltage power supply, there is no improvement in system frequency even if the inverter emits active power, but it can be confirmed that the inverter is operating normally.

Next, the case where the control signal from the voltage fluctuation suppressing operation mode executing means is used will be described. FIG. 9 shows that t = 0
A constant power operation of 30 kW is performed until 0.12 sec.
It is a response waveform at the time of starting the voltage fluctuation suppression function of the target voltage of 6640 V from 0.12 sec. t = 0 to 0.1
It can be seen that the reactive power is zero since the voltage fluctuation suppression function has not been activated until 2 sec, but after 0.12 sec, the inverter outputs the reactive power because the voltage fluctuation suppression function is working. In addition, it can be confirmed from the figure that the active power and the interconnection point voltage can be controlled, respectively, and the power storage function and the power quality improvement function can be simultaneously achieved. FIGS. 7B and 7C show the results of simulation and experiment of U-phase voltage and current. After the voltage fluctuation suppression function has been activated, the inverter has performed simulations and experiments of the delay current, and it can be confirmed that the two agree well.

FIG. 10 shows a constant power operation of 30 kW, and t
12 is a response waveform when the voltage fluctuation suppression function of the target voltage of 6560 V is started from 0.12 sec. It can be seen from the figure that the active power and the interconnection point voltage can be simultaneously controlled in the voltage decreasing direction.

Next, the case where the control signal from the unbalance suppression operation mode executing means is used will be described. The unbalanced voltage is represented by the sum of the positive-sequence voltage and the negative-sequence voltage. If the negative-sequence voltage can be reduced, the degree of unbalance of the voltage is also reduced. FIG. 11 is a simulation result of the positive-phase voltage and the negative-phase voltage of the interconnection point voltage when the unbalance suppression is performed and when it is not performed.
By performing the imbalance suppression, the positive phase component was not changed, but the reverse phase component was confirmed to have a reduction effect of about 50%.

Next, the case where the control signal from the harmonic suppression operation mode executing means is used will be described. FIG. 12 shows the frequency components of the U-phase line current when harmonic suppression is not performed and when harmonic suppression is performed. For the harmonic load, use a capacitor input type load.
The second and eleventh components are remarkably contained. It was confirmed that the effect of reducing harmonic components by 22% was obtained by performing harmonic suppression.

Next, test results obtained by combining a plurality of operation modes will be described. FIG. 13 is an example of the multi-function control operation, and is an experimental result of the active power and the U-phase inverter current when the sag is suppressed. After detecting a sag,
It can be seen that the constant power charging / discharging and voltage fluctuation suppression, which are common functions, are stopped, and the instantaneous sag suppression function is activated. It can be seen that, after the sag suppression, the constant power charge / discharge and voltage fluctuation suppression functions are activated again to return to the original state. From the output current of the inverter, it can be seen that the sag suppression is stable in about two to three cycles after startup.

[0044]

According to the present invention, a plurality of operation mode execution means determined in advance for realizing at least one of load leveling and power quality improvement of a power system can be used to generate power in an area where a power storage device is used. The operation mode required for load leveling and / or power quality improvement can be arbitrarily selected and specified by external operation according to the system status, so that the power storage device can be easily adapted to the area of use. Therefore, there is an advantage that versatility is enhanced and that it is possible to quickly respond to a change in the power situation in the use area.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a test circuit of a multifunctional inverter device.

FIG. 2 is a block diagram of the entire control system.

FIG. 3 is a partially enlarged view of FIG. 2;

FIG. 4 is a partially enlarged view of FIG. 2;

FIG. 5 is a block diagram illustrating an example of an embodiment of the present invention.

FIG. 6 is a diagram showing an SCAT simulation circuit for constant power charging and discharging.

FIGS. 7A and 7B show active power and reactive power responses of an inverter when constant power discharge is performed. FIG. 7A shows a simulation result, and FIG. 7B shows an experimental result.

FIGS. 8A and 8B show responses when the system frequency is changed from 60 Hz to 59 Hz. FIGS. 8A and 8B show simulation results, and FIG. 8C shows experimental results.

FIG. 9 shows a 30 kW constant power operation from t = 0 to 0.12 sec, and a target voltage 664 from t = 0.12 sec.
It is a response waveform at the time of starting the voltage fluctuation suppression function of 0V.

FIG. 10 shows a constant power operation of 30 kW, and t = 0.1
It is a response waveform at the time of starting the voltage fluctuation suppression function of the target voltage of 6560 V from 2 sec.

FIG. 11 is a diagram illustrating simulation results of the positive-phase voltage and the negative-phase voltage of the interconnection point voltage when unbalance suppression is performed and not performed.

FIG. 12 shows frequency components of U-phase line current when harmonic suppression is not performed and when harmonic suppression is performed.

FIG. 13 is a diagram showing experimental results of active power and U-phase inverter current when voltage sag is suppressed.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 power storage device 2 storage battery (power storage means) 3 power system 4 power storage device power converter 5 power system state detection means 6 power converter control device 7 to 15 operation mode execution means 16 mode designation means 17 operation mode selection output Means 18 Adder 19 Drive signal generating means

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Masahiko Suzuki 2-1-1 Hanamihama, Fukuma-cho, Munakata-gun, Fukuoka Inside Kyushu Transformer Co., Ltd. (72) Hiroshi Fukushima Hanami, Fukuma-cho, Munakata-gun, Fukuoka No. 1-1, Hama 2-chome Kyushu Transformer Co., Ltd. F term (reference) 5G066 EA03 FA01 FB13 FC11 GC01 HA15 HA19 HB09 JA01 JA05 JB03

Claims (4)

[Claims] A power storage means for storing power; a power storage means disposed between a power system and the power storage means, for converting AC power from the power system into DC power, and for storing the power with the DC power. A power converter control device for a power storage device used in a power converter for a power storage device that converts the DC power stored by the power storage means into AC power and supplies the AC power to the power system, Power system state detection means for detecting the state of the power system, controlling at least one of the active power and the reactive power output from the power converter for the power storage device, leveling the load of the power system and power In order to achieve at least one of the quality improvements, the power storage device power converter is driven in accordance with the detection output of the power system state detection means and a plurality of predetermined operation modes. Power converter control device for generating a drive signal for executing the plurality of operation modes, a plurality of operation mode execution units for generating control commands for executing the plurality of operation modes, and outputs of the plurality of operation mode execution units specified in advance Operation mode selection output means for selecting and outputting a driving signal; and a drive signal generating means for generating the drive signal based on the control command output from one or more operation mode execution means selected by the operation mode selection output means. And a power converter control device for a power storage device. 2. The method according to claim 1, wherein the operation mode selection unit is configured to, when at least two of the plurality of operation mode execution units are selected, select one or more of the operation modes having a predetermined higher priority. When the execution means is selected and the output is output from the one or more operation mode execution means having the higher priority, the output of the selected operation mode execution means having the other lower priority is output to the drive signal. 2. The output of the plurality of operation mode execution means is selected so as not to output to the generation means.
3. The power converter control device for a power storage device according to claim 1. 3. A constant power charge / discharge operation mode execution means for controlling the active power for leveling the load, a pattern operation mode execution means, and a load following operation mode. One operation mode execution means selected from the execution means, a power fluctuation suppressing operation mode execution means for controlling the active power for improving power quality, and a voltage fluctuation for controlling the reactive power for improving power quality. At least one operation mode execution means of the suppression operation mode execution means, the voltage sag suppression operation mode execution means, the voltage imbalance suppression operation mode execution means, the flicker suppression operation mode execution means, and the harmonic suppression operation mode execution means. The power fluctuation suppression operation mode execution means, the instantaneous sag suppression operation mode execution means, and the flicker suppression operation mode execution means But the power storage device for a power converter control apparatus according to claim 2 is a high one or more of the operation mode execution means of said priority. 4. The power storage according to claim 3, wherein the power fluctuation suppression operation mode execution means and the instantaneous sag suppression operation mode execution means have a higher priority than the flicker suppression operation mode execution means. Device power converter control device.