JP6852585B2 - AC / DC converter controller - Google Patents

Description

The present invention relates to an AC / DC converter control device that controls an AC / DC converter of a storage battery that charges / discharges active power and ineffective power to an electric power system.

A storage battery is connected to the power system, and when the demand for the power system is high, the storage battery is discharged to the power system, and when there is surplus power in the power system, the storage battery is charged from the power system. On the other hand, the number of re-energy power sources such as solar power generation facilities is increasing instead of the power generation system using synchronous generators. As the number of photovoltaic power generation facilities increases in the power system, the number of synchronous generators connected to the power system decreases.

In the power system, when the load on the power system increases or decreases, the synchronous generator connected to the same system bears the increase or decrease. The synchronous generator has the potential to suppress the frequency of the power system when it fluctuates, and since it is equipped with a speed governor, it suppresses it when the frequency fluctuates. Since the amount of power generation is adjusted in this way, it contributes to frequency stabilization. Since the photovoltaic power generation facility outputs a constant amount of power regardless of fluctuations in the load of the power system, if the number of synchronous generators in the power system is small, the inertial force of the synchronous generator will be lost when the load suddenly changes, and when the load suddenly changes. The change in frequency becomes large.

Therefore, the control device of the power conversion device of the storage battery calculates the operation of the synchronous generator itself corresponding to the load fluctuation or frequency fluctuation of the power system, and the frequency output from the synchronous generator at that time. Fluctuation suppression There is one in which the amount of power generation is output from the storage battery to the power system, and the fluctuation of the frequency is suppressed in the same manner as that of a synchronous generator by controlling the storage battery (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2013-162623

However, in Patent Document 1, the control device of the power conversion device outputs the amount of power generation for suppressing frequency fluctuations output from the power generation system modeled on the synchronous generator to the power system to suppress the frequency changes. , The calculation control content of the control device of the power conversion device becomes complicated.

An object of the present invention is an AC / DC converter control device capable of controlling an AC / DC converter of a storage battery and charging / discharging electric power to the electric power system to suppress a frequency change equivalent to that of a synchronous generator when the load of the electric power system suddenly changes. To provide.

The AC / DC converter control device according to the invention of claim 1 is an AC / DC converter control device that controls an AC / DC converter that charges / discharges active power and invalid power from a storage battery to a power system, and charges / discharges the power system from the storage battery. The phase of the output voltage of the AC / DC converter and the power control unit that outputs a control command to the AC / DC converter so that the active power and the ineffective power to be performed become the target values becomes the phase of the system voltage of the power system. The phase difference between the phase synchronization unit that outputs a signal synchronized with the phase of the system voltage to the power control unit and the system voltage obtained by the circuit having a circuit that delays the response of the phase synchronization unit. Based on this, a generator inertial force generating unit is provided, which calculates a frequency fluctuation suppression amount corresponding to the inertial force of the synchronous generator and adds it to the target value of the active power of the power control unit.

In the invention of claim 1, the AC / DC converter control device according to the invention of claim 2 calculates a frequency adjustment amount corresponding to the governor-free operation of the synchronous generator when the frequency of the power system fluctuates, and the power control unit. It is characterized in that it is provided with a governor-free control unit that adds to the target value of the active power.

According to the invention of claim 1, the generator inertial force generating unit outputs a signal synchronized with the phase of the system voltage to the power control unit so that the phase of the output voltage of the AC / DC converter becomes the phase of the system voltage of the power system. It has a circuit that delays the response of the phase synchronization unit, and calculates the amount of frequency fluctuation suppression equivalent to the inertial force of the synchronous generator based on the phase difference with the system voltage obtained in that circuit, and the power control unit is effective. Since it is added to the target value of electric power, the frequency drop of the electric power system can be greatly improved with a simple circuit.

According to the invention of claim 2, in addition to the effect of the invention of claim 1, the governor-free control unit calculates a frequency adjustment amount corresponding to the governor-free operation of the synchronous generator when the frequency of the power system fluctuates, and power is generated. Since it is added to the target value of the active power of the control unit, the frequency in the governor-free region can be adjusted in addition to suppressing the frequency decrease of the power system by the generator inertial force generating unit.

The block diagram of the AC / DC converter control device which concerns on 1st Embodiment of this invention. FIG. 3 is a waveform diagram of the response of the AC / DC converter control device according to the first embodiment of the present invention when the load of the electric power system suddenly changes. Waveform diagram of the response of the conventional AC / DC converter controller when the load of the power system suddenly changes. The block diagram of the AC / DC converter control device which concerns on 2nd Embodiment of this invention. FIG. 3 is a waveform diagram of the response of the AC / DC converter control device according to the second embodiment of the present invention when the load of the power system suddenly changes. Waveform diagram of the response of a conventional AC / DC converter controller with a governor-free function when the load suddenly changes.

Hereinafter, embodiments of the present invention will be described. FIG. 1 is a configuration diagram of an AC / DC converter control device according to a first embodiment of the present invention. FIG. 1 shows a power generation system 12 having a synchronous generator and an AC / DC converter storage battery system 13 that charges and discharges active power and ineffective power from a storage battery, and is connected to a photovoltaic power generation facility. The illustration of the rechargeable power source such as is omitted.

The power generation system 12 drives the synchronous generator 14 with the prime mover 15 to supply power to the load 16 of the power system 11, and the control device 17 outputs the synchronous generator 14 detected by the voltage detector 18a. The output current of the synchronous generator 14 detected by the voltage and current detector 19a is input, and the prime mover 15 and the synchronous generator 14 are controlled so that the output power reaches the target value.

The AC / DC converter storage battery system 13 controls the AC / DC converter 21 of the storage battery 20 to charge and discharge the active power and the ineffective power to the power system 11, and the AC / DC converter 21 passes through the reactor 22 and the transformer 23. It is connected to the power system 11.

Further, the AC / DC converter 21 is controlled by the AC / DC converter control device 24 according to the first embodiment of the present invention. The AC / DC converter control device 24 is detected by the output voltage (system voltage) of the transformer 23 detected by the voltage detector 18b, the output current of the transformer 23 detected by the current detector 19b1, and the current detector 19b2. The output current of the AC / DC converter 21 is input, and the active power and the ineffective power to be charged and discharged to the power system 11 are controlled to be the target values. At that time, the power corresponding to the inertial force of the synchronous generator 14 is output from the storage battery 20 to enhance the frequency maintenance effect.

The AC / DC converter control device 24 includes a power control unit 25, a phase synchronization unit 26, and a generator inertial force generating unit 27. The power control unit 25 outputs a control command to the AC / DC converter 21 so that the active power and the ineffective power charged / discharged from the storage battery 20 to the power system 11 become target values, and the phase synchronization unit 26 outputs the AC / DC converter 21. A signal synchronized with the phase of the system voltage is output to the power control unit 25 so that the phase of the output voltage of is the phase of the system voltage of the power system 11. Further, the generator inertial force generating unit 27 has a circuit in which the response of the phase synchronization unit 26 is delayed, and is equivalent to the inertial force of the synchronous generator 14 based on the phase difference with the system voltage obtained by the circuit. The amount of frequency fluctuation suppression is calculated and added to the target value of the active power of the power control unit 25.

The power calculation unit 28 of the power control unit 25 inputs the output voltage of the transformer 23 detected by the voltage detector 18b and the output current of the transformer 23 detected by the current detector 19b1 to input the AC / DC converter control device 24. The active power and the ineffective power output from are calculated, and the active power P and the ineffective power Q which are converted into two phases by three-phase and two-phase conversion are output. The active power P calculated by the power calculation unit 28 is input to the adder 29a1, and the reactive power Q calculated by the power calculation unit 28 is input to the adder 29b1. The three-phase / dq conversion unit 30a of the power control unit 25 inputs the output current (three-phase current) of the AC / DC converter 21 detected by the current detector 19b2, performs three-phase two-phase conversion, and performs two-phase conversion. The output current of the AC / DC converter 21 is output to the adders 29a2 and 29b2.

In the adder 29a1, the added value (P1 + Pi) obtained by adding the frequency fluctuation suppression amount Pi corresponding to the inertial force of the synchronous generator 14 output from the generator inertial force generating unit 27, which will be described later, to the active power target value P1 by the adder 29d1. And the difference ΔP from the active power P output from the AC / DC converter control device 24 is calculated and output to the active power regulator 31. Similarly, the adder 29b1 calculates the difference ΔQ between the invalid power target value Q1 and the invalid power Q output from the AC / DC converter control device 24 and outputs the difference ΔQ to the invalid power regulator 32.

The adder 29a2 calculates the difference between the output of the active power regulator 31 and the d-axis current converted into two-phase by the three-phase / dq converter 30a and outputs the difference to the d-axis current regulator 33. For the output of the d-axis current regulator 33, the adder 29a3 calculates the active power command value for charging / discharging by adding the phase angle signal from the phase synchronization unit 26 described later. Similarly, the adder 29b2 calculates the difference between the output of the ineffective power regulator 32 and the q-axis current converted into two-phase by the three-phase / dq converter 30a and outputs the difference to the q-axis current regulator 34. For the output of the q-axis current regulator 34, the adder 29b3 calculates an invalid power command value for charging / discharging by adding a phase angle signal from the phase synchronization unit 26 described later.

The active power command value from the adder 29a3 and the invalid power command value from the adder 29b3 are input to the dq / three-phase conversion unit 35, converted into two-phase and three-phase, and are converted into two-phase and three-phase, and the AC / DC converter 21 is transmitted via the gate pulse generator 36. Is entered in. As a result, the AC / DC converter 21 is controlled so that the active power and the ineffective power become target values, and the active power is obtained by adding the power corresponding to the inertial force of the synchronous generator 14 from the storage battery 20. To.

Next, the phase synchronization unit 26 outputs a signal synchronized with the phase of the system voltage to the power control unit 25 so that the phase of the output voltage of the AC / DC converter 21 becomes the phase of the system voltage of the power system 11. It is composed of a phase-locked loop PLL (Phase Locked Loop).

The three-phase / dq conversion unit 30b of the phase synchronization unit 26 inputs the output voltage (system voltage) of the transformer 23 detected by the voltage detector 18b, converts the three-phase system voltage into two phases, and at the same time, performs two phases. The phase angles (cosθH, sinθH) of the two-phase components of the internal signal (output voltage of the AC / DC converter 21) obtained by the phase component calculation unit 37a are input, and the phase of the system voltage and the phase of the internal signal are compared. Then, the comparison result is output as a phase angle signal to the adders 29a3 and 29b3 of the power control unit 25 and output to the phase difference detection unit 38a.

The phase difference detecting unit 38a calculates the phase difference ΦH between the phase of the system voltage and the phase of the internal signal and outputs the phase difference ΦH to the phase difference adjusting unit 39a. The phase difference adjusting unit 39a calculates an adjustment amount so that the phase difference ΦH becomes zero and outputs it to the adder 29c. The adder 29c adds the adjustment amount from the phase difference adjusting unit 39a and the reference frequency (frequency of the system voltage) to obtain the angular frequency ωH of the internal signal. The angular frequency ωH of the internal signal is input to the integrating element 40a, and the phase angle θH is obtained by the integrating element 40a. The phase angle θH obtained by the integrating element 40a is input to the two-phase component calculation unit 37a, and the phase angle (cos θH) of the two-phase component of the internal signal (output voltage of the AC / DC converter 21) is input by the two-phase component calculation unit 37a. , SinθH).

In this way, the phase synchronization unit 26 has a phase angle on the adders 29a3 and 29b3 of the power control unit 25 so that the phase of the internal signal (output voltage of the AC / DC converter 21) is the phase of the system voltage of the power system 11. It is output as a signal. As a result, the phase of the output voltage of the AC / DC converter 21 is adjusted so as to match the phase of the system voltage of the power system 11.

Next, the generator inertial force generating unit 27 has a circuit in which the response of the phase synchronization unit 26 is delayed, and the inertial force of the synchronous generator 14 is based on the phase difference with the system voltage obtained by the circuit. A considerable amount of frequency fluctuation suppression is calculated and added to the target value of the active power of the power control unit 25.

The phase-locked loop PLL of the generator inertial force generation unit 27 is composed of a three-phase / dq conversion unit 30c, a two-phase component calculation unit 37b, a phase difference detection unit 38b, a phase difference adjustment unit 39b, an adder 29c2, and an integrating element 40b. The phase-locked loop PLL of the phase-locked loop unit 26 (three-phase / dq conversion unit 30b of the phase synchronization unit 26, two-phase component calculation unit 37a, phase difference detection unit 38a, phase difference adjustment unit 39a, adder 29c1, integration element. The circuit configuration is the same as that of 40a). The phase-locked loop PLL of the generator inertial force generating unit 27 is a circuit in which the response of the phase-locked loop PLL of the phase-locked loop unit 26 is delayed.

The AC / DC converter 21 needs to instantly calculate what kind of voltage is generated with respect to the system voltage and control the output power of the storage battery 20 to become a desired power. That is, if the system voltage is different from the actual one, it is difficult to make the output power of the storage battery 20 the desired power. Therefore, it is necessary to keep the system voltage as close to the actual one as possible. Therefore, the control constant of the phase difference adjusting unit 39a of the phase synchronization unit 26 is determined so that the phase synchronization circuit PLL of the phase synchronization unit 26 has a faster response speed. On the other hand, the control constant of the phase difference adjusting unit 39b of the generator inertial force generating unit 27 is set so that the response is slower than the control constant of the phase difference adjusting unit 39a of the phase synchronization unit 26. This is because when the frequency of the power system 11 fluctuates due to a sudden change in the load 16 of the power system 11, the response is such that the frequency fluctuation of the power system 11 is suppressed in the same manner as the characteristics of the synchronous generator 14.

Since the phase-locked loop PLL of the phase-locked loop unit 26 responds faster than the phase-locked loop PLL of the generator inertial force generating unit 27, in FIG. 1, the various quantities of the phase-locked loop PLL of the phase-locked loop unit 26 are subscript H. Is attached, and a subscript L is attached to various quantities of the phase-locked loop PLL of the generator inertial force generating unit 27.

Then, the generator inertial force generation unit 27 is a phase-locked loop PLL of the generator inertial force generation unit 27 (three-phase / dq conversion unit 30b of the phase synchronization unit 26, two-phase component calculation unit 37a, phase difference detection unit 38a, In addition to the phase difference adjusting unit 39a, adder 29c1, and integrating element 40a), the inertia of the synchronous generator 14 is based on the phase difference ΦL with the system voltage obtained by the phase-locked loop PLL of the generator inertial force generating unit 27. It has an inertial force calculation unit 41 that calculates a frequency fluctuation suppression amount Pi corresponding to the force. The inertial force calculation unit 41 calculates the electric output {Pi = (1 / XT) * sinΦL} output by the synchronous generator 14 when the load suddenly changes, as the frequency fluctuation suppression amount Pi corresponding to the inertial force of the synchronous generator 14. XT is the reactance on the AC side of the AC / DC converter 21 (mainly the reactance of the AC reactor or the transformer), and ΦL is the phase difference between the phase of the system voltage and the phase of the internal signal (output voltage of the AC / DC converter 21).

The inertial force calculation unit 41 outputs the calculated frequency fluctuation suppression amount Pi to the adder 29d1. The adder 29d1 adds the frequency fluctuation suppression amount Pi to the target value P1 of the active power of the power control unit 25. As a result, the frequency fluctuation suppression amount Pi corresponding to the inertial force of the synchronous generator is added to the target value P1 of the active power, so that the frequency decrease of the power system 11 can be significantly improved when the load 16 of the power system 11 suddenly changes.

FIG. 2 is a waveform diagram of the response of the AC / DC converter control device according to the first embodiment of the present invention when the load of the power system suddenly changes, and FIG. 2 (a) is a waveform diagram of the generator output and the storage battery output with respect to the load fluctuation. 2 (b) is a waveform diagram of frequency fluctuation in the case of FIG. 2 (a). FIG. 2B shows a case where the reference frequency of the power system 11 is 50 Hz.

In FIG. 2A, it is assumed that the load of the power system 11 has rapidly increased from 2000 kW to 2500 kW at the time point t1. Since the synchronous generator 14 is connected to the electric power system 11, the synchronous generator 14 increases the output according to the load fluctuation of the electric power system. Further, since the AC / DC converter control device according to the first embodiment of the present invention has a generator inertial force generating function, power is generated from the storage battery 20 in response to a sudden load change in the power system 11. Is output to the power system 11. Therefore, as shown in FIG. 2B, the frequency fluctuation of the power system 11 fluctuates only about 0.3 Hz at the time t1 when the load suddenly increases.

FIG. 3 is a waveform diagram of the response of the conventional AC / DC converter controller when the load of the power system suddenly changes, FIG. 3 (a) is a waveform diagram of the generator output and the storage battery output with respect to the load fluctuation, and FIG. 3 (b) is a waveform diagram. It is a waveform diagram of the frequency fluctuation in the case of FIG. FIG. 3 is shown as a comparative example of FIG.

In FIG. 3A, it is assumed that the load of the power system 11 has suddenly increased from 2000 kW to 2500 kW at the time point t1. Since the synchronous generator 14 is connected to the electric power system 11, the synchronous generator 14 increases the output according to the load fluctuation of the electric power system. On the other hand, since the conventional AC / DC converter control device does not have a generator inertial force generating function, no additional power is output from the storage battery 20 due to a sudden change in the load of the power system 11. Therefore, as shown in FIG. 3B, the frequency fluctuation of the power system 11 greatly fluctuates from the time point t1 when the load suddenly increases to the time point t2 until the load fluctuation converges. As can be seen from FIGS. 2 and 3, according to the first embodiment of the present invention, the frequency drop of the power system 11 can be significantly improved when the load 16 of the power system 11 suddenly changes. Further, since the generator inertial force generation function can be realized by the phase-locked loop PLL, it can be realized by a simple circuit.

Next, a second embodiment of the present invention will be described. FIG. 4 is a configuration diagram of an AC / DC converter control device according to a second embodiment of the present invention. In this second embodiment, with respect to the first embodiment shown in FIG. 1, the frequency adjustment amount corresponding to the governor-free operation of the synchronous generator is calculated when the frequency of the power system fluctuates, and the active power of the power control unit 25 is calculated. The governor-free control unit 42 to be added to the target value of is additionally provided. The same elements as those in FIG. 1 are designated by the same reference numerals, and redundant description will be omitted.

The governor-free control unit 42 calculates the frequency adjustment amount ΔPf corresponding to the governor-free operation of the synchronous generator 14 when the system frequency of the power system 11 fluctuates. The governor-free operation outputs a frequency adjustment amount ΔPf that absorbs fluctuations in the system frequency for several seconds to several tens of seconds (up to about 1 to 2 minutes). The suppression of frequency fluctuations due to the inertial force of the synchronous generator 14 outputs a frequency fluctuation suppression amount Pi that absorbs fluctuations in the system frequency for 0 to a dozen seconds.

In FIG. 4, the system frequency f of the power system 11 is detected by the frequency detector 43, and the system frequency f detected by the frequency detector 43 is input to the adder 29e. The adder 29e calculates the difference between the system frequency f and the reference frequency f0 and outputs it to the function generator 44 as a frequency deviation Δf. The function generator 44 generates a frequency adjustment amount ΔPf corresponding to the governor-free operation of the synchronous generator 14 based on the frequency deviation Δf. The function generator 44 has a dead zone in which the frequency adjustment amount ΔPf becomes zero in a predetermined width with the frequency deviation Δf centered on zero, and when the absolute value of the frequency deviation Δf exceeds a predetermined value, the frequency adjustment amount ΔPf becomes a constant value. Has a function that In the range where the frequency deviation Δf does not exceed the dead zone and the absolute value does not exceed a predetermined value, the frequency adjustment amount ΔPf is represented by Pf = −K · Δf. K is the reciprocal of the speed arbitration rate (K = 1 / speed arbitration rate) in the synchronous generator 14.

When the system frequency f is lower than the reference frequency f0 and deviates from the dead zone, the frequency deviation Δf is negative, so that the frequency adjustment amount ΔPf that increases the discharge of the storage battery 20 is output from the function generator 44. On the contrary, when the system frequency f rises above the reference frequency f0 and deviates from the dead zone, the frequency deviation Δf is positive, so that the frequency adjustment amount ΔPf for reducing the discharge of the storage battery 20 is output from the function generator 44. To.

The frequency adjustment amount ΔPf from the governor-free control unit 42 is output to the adder 29d2. The adder 29d2 adds the frequency adjustment amount ΔPf from the governor-free control unit 42 and the frequency fluctuation suppression amount Pi corresponding to the inertial force of the synchronous generator 14 output from the generator inertial force generating unit 27, and addser 29d2. Output to. The adder 29d2 adds the frequency adjustment amount ΔPf and the frequency fluctuation suppression amount Pi and outputs an addition value (ΔPf + Pi) to the adder 29d1. The adder 29d1 adds the added value (ΔPf + Pi) to the target value P1 of the active power of the power control unit 25. As a result, the added value (ΔPf + Pi) of the frequency adjustment amount ΔPf from the governor-free control unit 42 and the frequency fluctuation suppression amount Pi corresponding to the inertial force of the synchronous generator is added to the target value P1 of the active power. When the load 16 suddenly changes, the frequency drop of the power system 11 can be significantly improved.

FIG. 5 is a waveform diagram of the response of the AC / DC converter control device according to the second embodiment of the present invention when the load of the power system suddenly changes, and FIG. 5 (a) is a waveform diagram of the generator output and the storage battery output with respect to the load fluctuation. 5 (b) is a waveform diagram of frequency fluctuation in the case of FIG. 5 (a). FIG. 5B shows a case where the reference frequency of the power system 11 is 50 Hz.

In FIG. 5A, it is assumed that the load of the power system 11 has suddenly increased from 2000 kW to 2500 kW at the time point t1. Since the synchronous generator 14 is connected to the electric power system 11, the synchronous generator 14 increases the output according to the load fluctuation of the electric power system. Further, since the AC / DC converter control device according to the second embodiment of the present invention has a generator inertial force generating function and a governor-free function, the load suddenly changes from the storage battery 20 as the load of the power system 11 suddenly changes. Correspondingly, power is output to the power system 11. Therefore, as shown in FIG. 2B, the frequency fluctuation of the power system 11 fluctuates only about 0.2 Hz at the time t1 when the load suddenly increases.

FIG. 6 is a waveform diagram of the response of a conventional AC / DC converter controller having a governor-free function when the load suddenly changes, and FIG. 6A is a waveform diagram of the generator output and the storage battery output with respect to the load fluctuation, FIG. b) is a waveform diagram of frequency fluctuation in the case of FIG. 6A. FIG. 6 is shown as a comparative example of FIG.

In FIG. 6A, it is assumed that the load of the power system 11 has rapidly increased from 2000 kW to 2500 kW at the time point t1. Since the synchronous generator 14 is connected to the electric power system 11, the synchronous generator 14 increases the output according to the load fluctuation of the electric power system. On the other hand, the conventional AC / DC converter control device has a governor-free function but does not have a generator inertial force generation function, so that power is additionally output from the storage battery 20 due to a sudden change in the load of the power system 11. Only those based on the governor-free function will be done. Therefore, as described above, the governor-free function outputs the frequency adjustment amount ΔPf that absorbs the fluctuation of the system frequency for several seconds to several tens of seconds (up to about 1 to 2 minutes), and the fluctuation of the system frequency is 0. The frequency fluctuation suppression amount Pi that absorbs the fluctuation of the system frequency for about ten and several seconds is not output. From this, as shown in FIG. 3B, the frequency fluctuation of the power system 11 greatly fluctuates from the time point t1 when the load suddenly increases to the time point t2 until the load fluctuation converges. When the generator has the inertial force generating function, as can be seen from FIG. 5, the frequency drop of the power system 11 can be significantly improved when the load 16 of the power system 11 suddenly changes. In the case of the second embodiment of the present invention, since it has a governor-free function, it is possible to absorb fluctuations in the system frequency from several seconds to several tens of seconds (up to about 1 to 2 minutes).

According to the second embodiment of the present invention, the frequency decrease can be significantly improved by adding the inertial force generation function in addition to the governor-free function to the AC / DC converter 21 of the storage battery system 13. Further, since the generator inertial force generation function can be realized by the phase-locked loop PLL, it can be realized by a simple circuit.

Although some embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other embodiments, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are also included in the scope of the invention described in the claims and the equivalent scope thereof.

11 ... Electric power system 12 ... Power generation system 13 ... AC / DC converter Storage battery system 14 ... Synchronous generator 15 ... Motor 16 ... Load 17 ... Control device 18 ... Voltage detector 19 ... Current detector 20 ... Storage battery 21 ... AC / DC converter 22 ... Reactor 23 ... Transformer 24 ... AC / DC converter control device 25 ... Power control unit 26 ... Phase synchronization unit 27 ... Generator inertial force generation unit 28 ... Power calculation unit 29 ... Adder 30 ... Three-phase / dq conversion unit 31 ... Effective Power regulator 32 ... Invalid power regulator 33 ... p-axis current regulator 34 ... q-axis current regulator 35 ... dq / three-phase conversion unit 36 ... Gate pulse generator 37 ... Two-phase component calculation unit 38 ... Phase difference detection unit 39 ... Phase difference adjusting unit 40 ... Integrating element 41 ... Inertial force calculation unit 42 ... Governor-free control unit 43 ... Frequency detector 44 ... Function generator

Claims (2)

In the AC / DC converter control device that controls the AC / DC converter of the storage battery that charges and discharges active power and invalid power to the power system.
A power control unit that outputs a control command to the AC / DC converter so that the active power and the ineffective power charged / discharged from the storage battery to the power system become target values.
A phase synchronization unit that outputs a signal synchronized with the phase of the system voltage to the power control unit so that the phase of the output voltage of the AC / DC converter becomes the phase of the system voltage of the power system.
The power control unit has a circuit in which the response of the phase synchronization unit is delayed, and the frequency fluctuation suppression amount corresponding to the inertial force of the synchronous generator is calculated based on the phase difference from the system voltage obtained in the circuit. An AC / DC converter control device including a generator inertial force generating unit that adds to the target value of active power. It is characterized by having a governor-free control unit that calculates a frequency adjustment amount corresponding to the governor-free operation of the synchronous generator when the frequency of the power system fluctuates and adds it to the target value of the active power of the power control unit. The AC / DC converter control device according to claim 1.

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