JP4049079B2 - Isolated operation detection method and power supply apparatus - Google Patents

Description

  The present invention converts a natural energy such as a solar battery or wind power generation into a power, detects a single operation of a grid-connected inverter linked to a grid, and optimally controls a voltage supplied to a load to increase a power saving effect. About.

  Conventionally, this kind of power-saving device is known for home use or business use, which has a function of reducing an excessive voltage of an alternating voltage and reducing power consumption (for example, see Patent Document 1).

  The power saving device will be described below with reference to FIG.

  As shown in the figure, a power saving apparatus 101 includes a series transformer 104 disposed between an AC power supply 102 and a load 103, and a regenerative inverter 105 whose output side is connected to the secondary winding of the series transformer 104. As a result, the voltage applied to the load 103 is controlled. Also, with this configuration, by continuously controlling the output of the regenerative inverter 105, the voltage applied to the load 103 can be continuously controlled, and stable power saving power can be supplied to the load 103 side.

  In addition, with respect to detection of isolated operation of a grid-connected inverter linked to a grid, a method is known in which a disturbance signal is output to the grid by an active method and detected by divergence of the disturbance signal (for example, Patent Document 2). reference).

  Hereinafter, the detection of the isolated operation will be described with reference to FIG.

As shown in the figure, a power supply device 106 that outputs DC power, such as a solar cell, an inverter circuit 107 that converts DC power output from the power supply device 106 into AC power, and a load 108 that is linked to the inverter circuit 107. Based on the voltage at the connection point detected by the voltage detection means 110, the voltage detection means 110 for detecting the voltage at the connection point between the inverter circuit 107 and the commercial power system 109. , The commercial power system 109 is stopped, the single operation determination unit 111 that determines that the commercial power system 109 is in the single operation state, the active fluctuation creation unit 112 that varies the output current of the inverter circuit 107, and the commercial power system 109 are stopped. When the single operation determination unit 111 determines that it is in the single operation state, the inverter circuit 107 and the commercial power system 109 are disconnected. The grid interconnection protection device 113 includes a random fluctuation output unit 114 when the output current of the inverter circuit 107 varies, so that a random value can be selected from a certain range of numerical values. The active variation signal is output at a random value variation amount at predetermined time intervals. By giving a random value variation, it is possible to detect an isolated operation even when a power generation facility that employs an active method is connected to the same wiring.
JP 2002-270884 A (Summary, FIG. 1) Japanese Patent No. 3402159 (FIG. 1)

  In such a conventional power saving device, it is possible to control the load voltage continuously by using an inverter, and to improve the power saving effect by supplying stable power saving power to the load. Yes, but you can't use natural energy. In addition, the grid-connected inverter can be used by converting the power extracted from natural energy into usable energy and linking it with the grid power supply. However, the load voltage is continuously controlled to save power to the load. There is a problem that it is impossible to control electric power and make effective use of electric power. From the viewpoint of preventing environmental destruction and global warming, effective use of electric power and energy saving using natural energy are strongly demanded.

  In addition, the isolated operation detection in the conventional photovoltaic power generation system outputs a disturbance signal to the system in an active manner, but the disturbance directly affects the load, and the instantaneous operation when the islanding state is entered. Has a problem of adversely affecting the load, and stability with respect to power supply is required.

  The present invention solves such a conventional problem, and uses power generated from natural energy by connecting a power generation device to a power saving device and effectively controlling an inverter. By supplying stable power saving power to the load as much as possible, it is possible to achieve both effective use of power and energy saving, and at the same time detecting the independent operation of the energy generating means in the compensation section of the power saving device or voltage stabilizing device, It is an object of the present invention to provide a power supply apparatus that can reduce disturbance output from a power supply supplied to the power supply to detect isolated operation.

  In order to achieve the above object, the isolated operation detection method of the present invention and the power supply apparatus thereof are a full-bridge converter composed of three arms in which diodes antiparallel to switching elements are connected in series vertically, and one arm is a full bridge. A full bridge inverter shared with the converter, a capacitor connected in parallel to the three arms, an AC power supply and a primary winding are connected in series, and a secondary winding is connected in series from the output of the full bridge inverter through a reactor. In the power saving device constituted by the main transformer which controls the series transformer, the full bridge converter and the full bridge inverter, or the voltage stabilizing device, the power generation means connected in parallel to the capacitor, and the full bridge converter Control as a grid-connected inverter of the power generation means And a grid interconnection control means for generating a disturbance signal for detecting an independent operation of the power generation means, a disturbance reduction control means for controlling the full-bridge inverter so that the disturbance signal is reduced, and power generation from the power generation means A power storage means for temporarily storing electric power, a charge / discharge means for charging or discharging the power storage means, and an amount of charge to the power storage means is changed when a disturbance signal increases by a certain amount, thereby detecting acceleration independently. The charging acceleration detecting means is provided.

  By this means, the power generation means is linked to the AC power source, and the power is generated in the reverse power flow, and the disturbance signal output for detecting the isolated operation is reduced from the power supply that supplies the load, so that the power generated from the natural energy can be reduced. In addition, since stable power saving power can be supplied to the load as before, it is possible to achieve both effective use of power and energy saving, and the energy saving device or voltage stabilization device compensation unit can be operated independently. In addition, it is possible to reduce the disturbance output for detecting the isolated operation from the power source supplied to the load, and to further increase the detection speed of the isolated operation by the charge acceleration detecting means. An operation detection method or a power supply device is obtained.

  In addition, a full bridge converter constituted by three arms in which diodes antiparallel to the switching element are connected in series up and down, a full bridge inverter sharing one arm with the full bridge converter, and the three arms connected in parallel. A capacitor, an AC power source, and a primary winding connected in series, and a series transformer in which a secondary winding is connected in series from the output of the full bridge inverter through a reactor, and the main controller that controls the full bridge converter and the full bridge inverter. In a power saving device or a voltage stabilization device configured by a circuit control unit, the power generation means connected in parallel to the capacitor, the full bridge converter is controlled as a grid-connected inverter of the power generation means, and the power generation means alone System that generates a disturbance signal for driving detection Interconnection control means, disturbance reduction control means for controlling the full-bridge inverter so that the disturbance signal is reduced, power storage means for temporarily storing the generated power from the power generation means, and charging to the power storage means Alternatively, the apparatus includes a charge / discharge unit that performs discharge and a discharge acceleration detection unit that changes the amount of discharge from the power storage unit when the disturbance signal increases by a certain amount to accelerate and detect an isolated operation.

  By this means, the power generation means is connected to an AC power source, and the power generated from the natural energy is reduced by reducing the disturbance signal output for detecting the isolated operation from the power source that reversely flows the power and supplying it to the load. In addition, since stable power saving power can be supplied to the load as before, it is possible to achieve both effective use of power and energy saving, and the compensation unit of the power saving device or voltage stabilizing device can be used as a stand-alone energy generator. At the same time that the operation is detected, it is possible to reduce the disturbance output for detecting the isolated operation from the power supply supplied to the load, and it is possible to increase the detection speed of the isolated operation by the discharge acceleration detecting means. An isolated operation detection method or a power supply device can be provided.

  According to the present invention, a full-bridge converter constituted by three arms in which diodes antiparallel to switching elements are connected in series up and down, a full-bridge inverter sharing one arm with a full-bridge converter, and the three arms A capacitor connected in parallel, an AC power source and a primary winding connected in series, and a series transformer in which a secondary winding is connected in series from the output of the full bridge inverter through a reactor, the full bridge converter, and the full bridge inverter In a power saving device or a voltage stabilization device configured by a main circuit control unit for controlling the power generation means connected in parallel to the capacitor, the full bridge converter is controlled as a grid-connected inverter of the power generation means, and Generates a disturbance signal to detect islanding operation of power generation means To the grid interconnection control means, the disturbance reduction control means for controlling the full-bridge inverter so that the disturbance signal is reduced, the power storage means for temporarily storing the generated power from the power generation means, and the power storage means The power generation means is configured to include charging / discharging means for performing charging or discharging, and charge acceleration detecting means for changing the amount of charge to the power storage means when the disturbance signal increases by a certain amount and accelerating the single operation. By connecting to an AC power source, reverse power flow and reducing the disturbance signal output for detection of isolated operation from the power supply supplied to the load, the power generated from natural energy can be used. As a result, stable power saving power can be supplied to the load as much as possible, making it possible to achieve both effective use of power and energy saving, and to create power in the compensation section of the power saving device or voltage stabilization device. At the same time as detecting the isolated operation of the means, the disturbance output for detecting the isolated operation from the power supply supplied to the load can be reduced, and the detection speed of the isolated operation can be increased by the charge acceleration detecting means. It is possible to provide an isolated operation detection method or a power supply device that has an effect of being able to be performed.

  In addition, a full bridge converter constituted by three arms in which diodes antiparallel to the switching element are connected in series up and down, a full bridge inverter sharing one arm with the full bridge converter, and the three arms connected in parallel. A capacitor, an AC power source, and a primary winding connected in series, and a series transformer in which a secondary winding is connected in series from the output of the full bridge inverter through a reactor, and the main controller that controls the full bridge converter and the full bridge inverter. In a power saving device or a voltage stabilization device configured by a circuit control unit, the power generation means connected in parallel to the capacitor, the full bridge converter is controlled as a grid-connected inverter of the power generation means, and the power generation means alone System that generates a disturbance signal for driving detection Interconnection control means, disturbance reduction control means for controlling the full-bridge inverter so that the disturbance signal is reduced, power storage means for temporarily storing the generated power from the power generation means, and charging to the power storage means Alternatively, the power generation means can be replaced with an AC power supply by comprising charging / discharging means for discharging, and discharge acceleration detecting means for changing the amount of discharge from the power storage means when the disturbance signal increases by a certain amount and accelerating and detecting the single operation. By using the power generated from natural energy by reducing the disturbance signal output for detecting isolated operation and reducing the disturbance signal output from the power supply to the load. Stable power saving power can be supplied to the power supply, enabling both efficient use of power and energy savings, and the compensation part of the power saving device or voltage stabilizing device At the same time as detecting the isolated operation, it is possible to reduce the disturbance output for detecting the isolated operation from the power supply supplied to the load, and to further increase the detection speed of the isolated operation by the discharge acceleration detecting means. It is possible to provide an isolated operation detection method or a power supply device that is effective.

  The invention according to claim 1 of the present invention is a full bridge converter configured by three arms in which diodes antiparallel to switching elements are connected in series vertically, and a full bridge inverter sharing one arm with the full bridge converter, A capacitor connected in parallel to the three arms, a series transformer in which an AC power source and a primary winding are connected in series, and a secondary winding is connected in series from the output of a full bridge inverter through a reactor; and the full bridge In a power saving device constituted by a converter, a main circuit control unit for controlling a full bridge inverter, or a voltage stabilizing device, a power generation means connected in parallel to the capacitor, and the full bridge converter as a grid interconnection inverter of the power generation means For controlling and detecting the independent operation of the power generation means Grid connection control means for generating a disturbance signal, disturbance reduction control means for controlling the full-bridge inverter so that the disturbance signal is reduced, power storage means for temporarily storing generated power from the power generation means, Charging / discharging means for charging or discharging the power storage means, and charge acceleration detecting means for changing the charge amount to the power storage means when the disturbance signal increases by a certain amount to detect the single operation acceleration. Yes, the power generated from natural energy is used by connecting the power generation means to an AC power source to reverse the power flow and reducing the disturbance signal output to detect the isolated operation from the power supply to the load. In addition, stable power-saving power can be supplied to the load as before, enabling both effective use of power and energy saving, and power-saving devices or voltage stabilization. At the same time, it is possible to reduce the disturbance output from the power supply supplied to the load to detect the isolated operation, and the charge acceleration detection means detects the isolated operation speed. It has the effect that it can be possible to raise.

  In addition, a full bridge converter constituted by three arms in which diodes antiparallel to the switching element are connected in series up and down, a full bridge inverter sharing one arm with the full bridge converter, and the three arms connected in parallel. A capacitor, an AC power source, and a primary winding connected in series, and a series transformer in which a secondary winding is connected in series from the output of the full bridge inverter through a reactor, and the main controller that controls the full bridge converter and the full bridge inverter. In a power saving device or a voltage stabilization device configured by a circuit control unit, the power generation means connected in parallel to the capacitor, the full bridge converter is controlled as a grid-connected inverter of the power generation means, and the power generation means alone System that generates a disturbance signal for driving detection Interconnection control means, disturbance reduction control means for controlling the full-bridge inverter so that the disturbance signal is reduced, power storage means for temporarily storing the generated power from the power generation means, and charging to the power storage means Or, it is configured to include a charge / discharge means for discharging and a discharge acceleration detecting means for changing the amount of discharge from the power storage means when the disturbance signal increases by a certain amount and accelerating and detecting the single operation. By using the power generated from natural energy by reducing the disturbance signal output for detecting the islanding operation from the power supply connected to the power source and reverse power flow, Since stable power saving power can be supplied to the load, it is possible to achieve both effective use of power and energy saving, and the energy saving device or voltage stabilization device compensation unit At the same time, it is possible to reduce the disturbance output from the power supply supplied to the load to detect the isolated operation, and to further increase the detection speed of the isolated operation by the discharge acceleration detection means Has the effect of being able to

  Further, the grid interconnection control means includes a frequency disturbance generation means for generating a disturbance in the frequency, and the disturbance reduction control means includes a frequency disturbance reduction means for reducing the frequency disturbance. By generating the signal, the primary detection can be performed.

  The grid interconnection control means includes current amplitude disturbance generating means for generating disturbance in the current amplitude, and the disturbance reduction control means includes current amplitude disturbance reducing means for reducing disturbance of the current amplitude. The primary detection of the single operation can be made possible by generating a disturbance signal having a current amplitude.

  Further, the grid interconnection control means includes a current phase disturbance generation means for generating a disturbance in the current phase, and the disturbance reduction control means includes a current phase disturbance reduction means for reducing the current phase disturbance. The primary detection of the single operation can be made possible by generating the disturbance signal of the current phase.

  In addition, the detection of the isolated operation is configured to be detected by a capacitor voltage fluctuation detecting means for detecting a decrease or increase in the voltage of the capacitor, and abruptly caused by the regenerative operation of the full bridge converter and the power running operation of the full bridge inverter. By detecting the reduction in the power of the capacitor, it has the effect that the primary detection of the single operation can be made possible.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
FIG. 1 shows a configuration diagram of a power supply apparatus according to Embodiment 1 of the present invention. In the figure, a power supply device is arranged between the AC power supply 1 and the load. The power supply device includes a power saving device 2 that adjusts the power supply voltage of the power supplied from the AC power supply 1 to a voltage required by the user. Further, the power saving device 2 includes a full bridge converter 5 and a full bridge inverter 6 in which one arm is shared with the full bridge converter 5 by three arms in which a diode 4 antiparallel to the switching element 3 is vertically connected in series. . Further, a capacitor 7 connected in parallel with the full bridge converter 5 and the full bridge inverter 6, and the solar power generation means 8 are linked to the capacitor 7. Furthermore, the secondary winding of the series transformer 9 is connected to the output of the full bridge inverter 6, and the primary winding side is connected in series to the AC power source 1 and the load. The full bridge converter 5 is arranged and configured to operate as a grid-connected inverter of the solar power generation means 8, that is, the switching elements 3a to 3d are driven by PWM modulation as current control type inverters. Further, the grid interconnection control means 10 generates a disturbance signal for detecting an isolated operation with respect to the interruption of the AC power supply 1 when the generated power from the solar power generation means 8 is supplied to the AC power supply 1 or the load. appear. Moreover, the disturbance reduction control means 11 which reduces the generated disturbance and supplies power to the load is connected. Further, the power storage means 12 that temporarily stores the generated power from the solar power generation means 8, the charge / discharge means 13 that controls the charging or discharging of the power storage means 12, and the amount of disturbance signal generated for detecting an independent operation are A charge acceleration detecting means 14 is provided for changing the amount of charge to the power storage means 12 when the specified value K1 is exceeded, and detecting the single operation in an accelerated manner.

  Next, the configuration of the grid interconnection control means 10 will be described with reference to FIG. As shown in the figure, the grid interconnection control means 10 calculates the current command value so that the generated power and the excess power of the AC power source 1 regenerated from the series transformer 9 through the full bridge inverter 6 flow backward to the AC power source 1. A reverse flow calculation unit 10a to perform, a disturbance calculation unit 10b to calculate a disturbance superimposed on a reverse flow current, and a reverse flow to control the output by adding the calculated disturbance to the current command value calculated by the reverse flow calculation unit 10a The output control unit 10c is configured.

  Next, the flowchart of the reverse power flow calculation unit 10a will be described with reference to FIG. As shown in the figure, the reverse power flow calculation unit 10a inputs the voltage of the capacitor 7 and performs PI control based on the difference value from the target voltage of the capacitor 7 to control the voltage of the capacitor 7 to be constant. The reverse current command value is calculated as a command value by inputting a deviation between the actual voltage Vt of the capacitor 7 and the target voltage Vt * to the PI controller.

  Next, a flowchart of the disturbance calculation unit 10b will be described with reference to FIG. As shown in the figure, the disturbance calculation unit 10b calculates a disturbance signal Iir superimposed on the phase θ1. The initial value of the peak value of the disturbance signal Iir is Iir (0). If there is a possibility that the operation is an independent operation, if the disturbance signal Iir (t) at that time is a positive value, ΔIir is added and updated. If Iir (t) is a negative value, ΔIir is subtracted and updated. The possibility of the isolated operation is determined by monitoring the fluctuation of the power supply voltage of the AC power supply 1 and determining the occurrence of distortion due to the superposition of a disturbance signal on the phase θ1 of the power supply voltage.

  Next, a control flowchart of the disturbance reduction control unit 11 that reduces the generated disturbance and supplies power to the load will be described with reference to FIG. As shown in the figure, the disturbance reduction control means 11 detects distortion of the power supply voltage supplied to the load, and supplies the voltage supplied to the actual load so that the power supply voltage supplied to the load becomes a target sine wave voltage. Is calculated, that is, a necessary distortion correction signal is calculated. The calculated correction signal and the deviation signal obtained by comparing and calculating the target voltage and the detected voltage as the power saving device 2 are added to calculate the total compensation. The compensation voltage of the full bridge inverter 6 is calculated by multiplying the transformation ratio of the series transformer 9. When the calculated compensation voltage exceeds the instantaneous voltage that can be compensated, the distortion correction signal is controlled to be within the output possible range of the full bridge inverter 6. By controlling the full bridge inverter 6 with the calculated command value, compensation of the disturbance signal generated by the full bridge converter 5 and voltage compensation as the power saving device 2 are performed.

  Next, a control flowchart of the charge acceleration detecting means 14 that changes the amount of charge to the power storage means 12 when the amount of the disturbance signal for detecting the isolated operation exceeds a specified value K1 and detects the isolated operation in an accelerated manner. This will be described with reference to FIG. As shown in the figure, the charge acceleration detecting means 14 monitors the command value of the disturbance signal generated by the grid interconnection control means 10. When the command value of the disturbance signal being monitored exceeds K1, the charging power to the power storage means 12 is increased, that is, the generated power from the solar power generation means 8 that causes the AC power supply 1 to flow backward is suppressed. The suppression control is limited to 1 / K2 times the generated power that is currently generated. When the power supply voltage of the AC power supply 1 drops while the generated power is being suppressed, the power saving device 2 that adjusts the power supply voltage of the power supply supplied from the AC power supply 1 to the voltage required by the user is in accordance with the dropped voltage. Thus, supply adjustment to the load is performed. At this time, when the voltage adjustment value exceeds the specified value, a drop in the power supply voltage of the AC power supply 1, that is, an isolated operation is detected.

  As described above, according to the present embodiment, power is supplied to the load at a stable voltage, and a disturbance signal for detecting an independent operation of a power generation means such as solar power generation is compensated for the load. The disturbance can be reduced, and the isolated operation can be detected more quickly by narrowing the output of the power generation means such as photovoltaic power generation from the isolated operation signal detected with higher sensitivity.

  In the present embodiment, the suppression control is 1 / K2 times the generated power that is currently generated, but it may be the specified generated power W1.

  In this embodiment, the power generation means is solar power generation. However, wind power generation, wave power generation, geothermal power generation, or the like may be used.

(Embodiment 2)
The same parts as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  FIG. 7 shows a configuration diagram of a power supply device according to the second embodiment of the present invention. In the figure, the power supply device is provided with discharge acceleration detecting means 15.

  Next, a control flowchart of the discharge acceleration detecting means 15 that changes the discharge amount from the power storage means 12 when the amount of the disturbance signal for detecting the isolated operation exceeds a specified value K1 and detects the isolated operation in an accelerated manner. This will be described with reference to FIG. As shown in the figure, the discharge acceleration detecting means 15 monitors the command value of the disturbance signal generated by the grid interconnection control means 10. When the command value of the disturbance signal being monitored exceeds K1, the power stored in the power storage unit 12 is superimposed on the generated power from the solar power generation unit 8 to be reversely flowed to the AC power supply 1, and the reverse flow is performed. By this superposition control, the generated power is increased up to K3 times the generated power. When the power supply voltage of the AC power supply 1 rises during the superimposition control, the power saving device 2 that adjusts the power supply voltage of the power supply supplied from the AC power supply 1 to a voltage requested by the user is supplied to the load according to the increased voltage. Will be adjusted. From the increase in the supply adjustment amount at this time, a drop in the power supply voltage of the AC power supply 1, that is, an isolated operation is detected.

  As described above, according to the present embodiment, power is supplied to the load at a stable voltage, and a disturbance signal for detecting an independent operation of a power generation means such as solar power generation is compensated for the load. Disturbance can be reduced, and by reversely flowing the power stored in the power storage means by superimposing the power stored in the power storage means from the isolated operation signal detected with higher sensitivity to the output of the power generation means such as solar power generation, The single operation can be detected quickly.

  In the present embodiment, the superimposition control is K3 times the generated power that is currently generated, but it may be up to the rated output of the full bridge inverter.

  In this embodiment, the power generation means is solar power generation. However, wind power generation, wave power generation, geothermal power generation, or the like may be used.

(Embodiment 3)
In addition, the same number is attached | subjected to the same part as Embodiment 1 or Embodiment 2, and the detailed description is abbreviate | omitted.

  FIG. 9 shows a configuration diagram of a power supply device according to the third embodiment of the present invention. In the figure, the power supply device is provided with frequency disturbance generating means 16, and the disturbance reduction control means 11 is provided with frequency disturbance reducing means 17 for reducing frequency disturbance.

  Next, frequency disturbance generation and reduction from the moment when the AC power supply 1 is cut off will be described with reference to FIG. 10, the flowchart of the frequency disturbance generation means 16 will be described with reference to FIG. 11, and the flowchart of the frequency disturbance reduction means 17. This will be described with reference to FIG. As shown in FIG. 10, the frequency disturbance generating unit 16 uses the full-bridge converter 5 to regenerate the generated power from the solar power generation unit 8 and the current waveform for regenerating excess power as the power saving device 2 from the power supply frequency f1. Control to raise to f2. Further, the frequency disturbance reducing means 17 for reducing the frequency disturbance has a full compensation amount because the frequency of the power supply to the load increases when the AC power supply 1 is cut off and the single operation is assumed. A steep increase is caused by the disturbance signal generated by the bridge converter 5. The steep increase causes the full bridge converter 5 to operate at the increased frequency even when the voltage phase jump does not occur at the moment when the single operation is started, that is, when the voltage phase and the current phase are equal. However, since the full bridge inverter 6 is controlled so as to have the power supply voltage of the basic power supply frequency (50 Hz or 60 Hz), the compensation amount of the full bridge inverter 6 is the same even when the voltage and current phase are equal at the start of the independent operation. It will increase with time. As a result, when the compensation amount exceeds the compensation limit value, it is detected that the vehicle is operating alone. When it is detected that it is an independent operation, the full bridge converter 5 and the full bridge inverter 6 perform a gate block and control so that the photovoltaic power generation means 8 is disconnected from the AC power source 1. Further, as shown in FIG. 11, the frequency disturbance generating means 16 calculates the power supply frequency f <b> 1 from the voltage detection value of the AC power supply 1. Regenerative current control is performed by adding Δf for the frequency disturbance to the calculated power supply frequency f1. The regenerative current control is controlled by appropriately switching the switching elements 3a to 3d. At this time, if the compensation amount increase flag of the full bridge inverter 6 is 1, the amount of disturbance is increased. If the compensation amount increase flag is 0, control is performed so that the amount of disturbance generated is returned to the initial value. Next, as shown in FIG. 12, the frequency disturbance reducing means 17 first calculates the deviation between the target voltage supplied to the load and the actual voltage. A target compensation amount obtained by multiplying the calculated deviation by the transformation ratio of the series transformer 9 is calculated. If the calculated target compensation amount has increased compared to the previous value, the compensation amount increase flag is changed to 1. If there is no decrease or change, the compensation amount increase flag is cleared to 0. Compensation by the full bridge inverter 6 controls the switching elements 3c to 3f by switching as appropriate. Further, when the amount of the disturbance signal for detecting the isolated operation of the frequency disturbance generating means 16 exceeds the specified value K1, the AC power supply is determined from the power supply adjustment amount to the load by the charge acceleration detecting means 14 and the power saving device 2. 1 is detected, that is, an isolated operation is detected.

  As described above, according to the present embodiment, the frequency disturbance generating unit 16 that generates a disturbance in the frequency, the frequency disturbance reducing unit 17 that reduces the generated disturbance of the frequency, and the charge acceleration detecting unit 14 are provided. At the same time as detecting a single operation at high speed, it is possible to reduce the influence of disturbance on the power supplied to the load.

  In this embodiment, the power generation means is solar power generation, but it may be wind power generation, wave power generation, geothermal power generation, or the like.

(Embodiment 4)
The same parts as those in the first to third embodiments are denoted by the same reference numerals, and detailed description thereof is omitted.

  FIG. 13 shows a configuration diagram of a power supply device according to the fourth embodiment of the present invention. In the figure, the power supply apparatus includes a current amplitude disturbance generating unit 18, and the disturbance reduction control unit 11 includes a current amplitude disturbance reducing unit 19 that reduces the disturbance of the current amplitude.

  Next, voltage amplitude disturbance and reduction of disturbance due to generation of disturbance of current amplitude from the moment when the AC power supply 1 is turned off will be described with reference to FIG. 14, and a flowchart of the current amplitude disturbance generation means 18 will be described with reference to FIG. The flowchart of the current amplitude disturbance reducing means 19 will be described with reference to FIG. As shown in FIG. 14, the current amplitude disturbance generating means 18 has a phase θf1 to θf2 in a current command for regenerating the generated power from the solar power generation means 8 and the excess power as the power saving device 2 by the full bridge converter 5. The period is controlled to superimpose the harmonic current. Further, the current amplitude disturbance reducing means 19 for reducing the disturbance of the current amplitude compensates for the adverse effect of the voltage distortion of the power source supplied to the load when the single operation occurs. Output to compensate the wave. When the compensation amount by the full bridge inverter 6 is increased, the amount of the disturbance is further increased. When the compensation amount at that time continues to exceed the current disturbance compensation limit value, the charge acceleration detection means 14 and the power saving device 2 From the power supply adjustment amount to the load, the power supply voltage drop of the AC power supply 1, that is, the single operation is detected. When it is detected that it is an independent operation, the full bridge converter 5 and the full bridge inverter 6 perform a gate block, disconnect the photovoltaic power generation means 8 from the AC power source 1, and finally control to stop. Next, as shown in FIG. 15, the current amplitude disturbance generating means 18 calculates the power supply voltage effective value from the voltage detection value of the AC power supply 1. Regenerative current control is performed by adding ΔVac_ipeek for the current amplitude disturbance to the calculated power supply voltage effective value Vac_rms. In the regenerative current control, the switching elements 3a to 3d are appropriately controlled by switching. At this time, if the compensation amount increase flag of the full bridge inverter 6 is 1, the amount of disturbance is increased. If the compensation amount increase flag is 0, control is performed so that the amount of disturbance generated is returned to the initial value. As shown in FIG. 16, the current amplitude disturbance reducing means 19 calculates the deviation between the target voltage supplied to the load and the actual voltage. A target compensation amount obtained by multiplying the calculated deviation by the transformation ratio of the series transformer 9 is calculated. If the calculated target compensation amount has increased compared to the previous value, the compensation amount increase flag is changed to 1. If there is no decrease or change, the compensation amount increase flag is cleared to 0. Compensation by the full bridge inverter 6 controls the switching elements 3c to 3f by switching as appropriate.

  As described above, according to the present embodiment, the current amplitude disturbance generating means 18 for generating a disturbance in the current amplitude, the current amplitude disturbance reducing means 19 for reducing the generated current amplitude disturbance, and the charge acceleration detecting means 14 are provided. As a result, it is possible to detect the single operation at high speed and simultaneously reduce the influence of the disturbance on the power supplied to the load.

  In this embodiment, the power generation means is solar power generation, but it may be wind power generation, wave power generation, geothermal power generation, or the like.

(Embodiment 5)
The same parts as those in the first to fourth embodiments are denoted by the same reference numerals, and detailed description thereof is omitted.

  FIG. 17 shows a configuration diagram of a power supply device according to the fifth embodiment of the present invention. In the figure, the power supply apparatus includes a current phase disturbance generation unit 20, and the disturbance reduction control unit 11 includes a current phase disturbance reduction unit 21 that reduces a current phase disturbance.

  Next, voltage disturbance due to the occurrence of disturbance in the current phase from the moment when the AC power supply 1 is cut off and the reduction of the disturbance will be described with reference to FIG. 18, and the flowchart of the current phase disturbance generating means 20 will be described with reference to FIG. The current phase disturbance reducing means 21 will be described with reference to FIG. As shown in FIG. 18, the current phase disturbance generating unit 20 generates a current command for regenerating the generated power from the solar power generation unit 8 and the excess power as the power saving device 2 by the full bridge converter 5 with respect to the voltage phase. A command is output so as to be delayed by θv1. Since the current phase disturbance reducing means 21 for reducing the current phase disturbance normally only injects reactive power into the current phase disturbance to the AC power supply 1, the voltage fluctuation of the AC power supply 1 does not occur. There is no compensation. When the AC power supply 1 is cut off, the excess power regeneration as the solar power generation means 8 and the power saving device becomes a voltage source, and therefore the disturbance generated by the current phase disturbance generation means 20 directly affects the load. Become. Since the disturbance that affects this is detected as an isolated operation, if the compensation amount of the current phase disturbance from the full bridge inverter 6 increases, the generation amount is further increased, and the compensation amount of the full bridge inverter 6 becomes the current phase disturbance compensation limit. When the value is exceeded, the power supply voltage drop of the AC power supply 1, that is, the single operation is detected from the adjustment amount of power supply to the load by the charge acceleration detecting means 14 and the power saving device 2. When it is detected that it is an independent operation, the full bridge converter 5 and the full bridge inverter 6 perform a gate block, disconnect the photovoltaic power generation means 8 from the AC power source 1, and finally control to stop. Next, as shown in FIG. 19, the current phase disturbance generating means 20 calculates the power supply voltage effective value and the phase from the voltage detection value of the AC power supply 1. Regenerative current control is performed by adding the phase delay θi1 corresponding to the current phase disturbance to the phase θ of the calculated power supply voltage effective value Vac_rms. In the regenerative current control, the switching elements 3a to 3d are appropriately controlled by switching. At this time, if the compensation amount increase flag of the full bridge inverter 6 is 1, the amount of disturbance is increased. If the compensation amount increase flag is 0, control is performed so that the amount of disturbance generated is returned to the initial value. Further, as shown in FIG. 20, the current phase disturbance reducing means 21 calculates a deviation between the target voltage supplied to the load 2 and the actual voltage. A target compensation amount obtained by multiplying the calculated deviation by the transformation ratio of the series transformer 9 is calculated. If the calculated target compensation amount has increased compared to the previous value, the compensation amount increase flag is changed to 1. If there is no decrease or change, the compensation amount increase flag is cleared to 0. Compensation by the full bridge inverter 6 controls the switching elements 3c to 3f by switching as appropriate.

  As described above, according to the present embodiment, the current phase disturbance generating means 20 for generating a disturbance in the current phase, the current phase disturbance reducing means 21 for reducing the generated current phase disturbance, and the charge acceleration detecting means 14 are provided. By providing, it is possible to detect the single operation at high speed and simultaneously reduce the influence of disturbance on the power supply supplied to the load.

  In this embodiment, the power generation means is solar power generation, but it may be wind power generation, wave power generation, geothermal power generation, or the like.

(Embodiment 6)
The same parts as those in the first to fifth embodiments are denoted by the same reference numerals, and detailed description thereof is omitted.

  FIG. 21 shows a configuration diagram of a power supply device according to the sixth embodiment of the present invention. In the figure, the power supply device is provided with capacitor voltage fluctuation detecting means 22 for detecting the voltage drop or rise of the capacitor 7.

  Next, the operation of the power supply apparatus from the moment when the AC power supply 1 is cut off will be described with reference to FIG. As shown in the figure, after the AC power supply 1 is cut off, the power supply to the load is only from the solar power generation means 8. At this time, when the power supplied from the solar power generation means 8 is larger than the load, the solar power generation means 8 that causes the full bridge converter 5 to reversely flow to the AC power supply 1 needs to be narrowed down. For this reason, supply voltage adjustment to the load in the power saving device 2 works, so that the supply voltage to the load is stabilized. Here, the DC intermediate voltage rises due to the regenerative power generated by the full bridge inverter 6, that is, the voltage of the capacitor 7 rises. Alternatively, when the load is greater than the power supplied from the solar power generation means 8, the power that causes the full-bridge converter 5 to reversely flow to the AC power supply 1 is insufficient. For this reason, supply voltage adjustment to the load in the power saving device 2 works, so that the supply voltage to the load is stabilized. Here, the DC intermediate voltage drops due to the power running operation by the full bridge inverter 6, that is, the voltage of the capacitor 7 drops.

  As described above, according to the present embodiment, since the voltage of the capacitor 7 fluctuates in the single operation state, the single voltage operation is detected by the capacitor voltage fluctuation detecting means 22 that detects the voltage fluctuation of the capacitor 7. Can be detected, and at the same time, it is possible to reduce the influence of disturbance on the power supply supplied to the load.

  In this embodiment, the power generation means is solar power generation, but it may be wind power generation, wave power generation, geothermal power generation, or the like.

  When power generators such as wind power generation, solar power generation, wave power generation, geothermal power generation, etc. are connected to the grid, it is possible not only to generate power but also to prevent excessive supply of power in the equipment by power saving devices. It can be applied to non-residential system applications such as office buildings.

Power supply device configuration diagram according to Embodiment 1 of the present invention Configuration diagram of the same-system interconnection control means Flow chart of reverse flow calculation unit Flow chart of the disturbance calculation unit Flow chart of the disturbance reduction control means Control flow chart of the charge acceleration detecting means Power supply device configuration diagram according to Embodiment 2 of the present invention Control flow chart of the discharge acceleration detecting means Power supply configuration diagram in Embodiment 3 of the present invention Illustration of disturbance generation and reduction at the same frequency Flow chart of the same frequency disturbance generating means Flow chart of the same frequency disturbance reducing means Power supply device configuration diagram according to Embodiment 4 of the present invention Explanatory diagram of disturbance and reduction of voltage amplitude due to occurrence of disturbance with same current amplitude Flow chart of current amplitude disturbance generating means Flow chart of means for reducing current amplitude disturbance Power supply device configuration diagram in Embodiment 5 of the present invention Explanatory diagram of voltage disturbance and disturbance reduction due to disturbance of the same current phase Flow chart of current phase disturbance generating means Explanatory diagram of means for reducing current phase disturbance Power supply device configuration diagram in Embodiment 6 of the present invention Operation diagram of the power supply when the AC power supply is shut off Configuration diagram of conventional power-saving device Configuration diagram of a power supply with conventional isolated operation detection

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 AC power supply 2 Power saving device 3 Switching element 4 Diode 5 Full bridge converter 6 Full bridge inverter 7 Capacitor 8 Solar power generation means 9 Series transformer 10 Grid connection control means 11 Disturbance reduction control means 12 Power storage means 13 Charging / discharging means 14 Charging Acceleration detection means 15 Discharge acceleration detection means 16 Frequency disturbance generation means 17 Frequency disturbance reduction means 18 Current amplitude disturbance generation means 19 Current amplitude disturbance reduction means 20 Current phase disturbance generation means 21 Current phase disturbance reduction means 22 Capacitor voltage fluctuation detection means 22

Claims (12)

A full bridge converter composed of three arms vertically connected in series with a diode in reverse parallel to the switching element, a full bridge inverter sharing one arm with the full bridge converter, and a capacitor connected in parallel to the three arms; A series transformer in which an AC power source and a primary winding are connected in series and a secondary winding is connected in series from the output of the full bridge inverter through a reactor, and the main circuit control for controlling the full bridge converter and the full bridge inverter In a power saving device or a voltage stabilization device configured by a unit, the power generation means connected in parallel to the capacitor and the full bridge converter are controlled as a grid-connected inverter of the power generation means, and the single operation detection of the power generation means is detected System to generate disturbance signal for Control means, disturbance reduction control means for controlling the full-bridge inverter so that the disturbance signal is reduced, power storage means for temporarily storing generated power from the power generation means, and charging of the power storage means, or An isolated operation detection method comprising: charge / discharge means for discharging; and charge acceleration detection means for detecting the acceleration of the isolated operation by changing a charge amount to the power storage means when a disturbance signal increases by a certain amount. A full bridge converter composed of three arms vertically connected in series with a diode in reverse parallel to the switching element, a full bridge inverter sharing one arm with the full bridge converter, and a capacitor connected in parallel to the three arms; A series transformer in which an AC power source and a primary winding are connected in series and a secondary winding is connected in series from the output of the full bridge inverter through a reactor, and the main circuit control for controlling the full bridge converter and the full bridge inverter In a power saving device or a voltage stabilization device configured by a unit, the power generation means connected in parallel to the capacitor and the full bridge converter are controlled as a grid-connected inverter of the power generation means, and the single operation detection of the power generation means is detected System to generate disturbance signal for Control means, disturbance reduction control means for controlling the full-bridge inverter so that the disturbance signal is reduced, power storage means for temporarily storing generated power from the power generation means, and charging of the power storage means, or A power supply device comprising: charge / discharge means for discharging; and charge acceleration detection means for changing the amount of charge to the power storage means when the disturbance signal increases by a certain amount to detect single operation acceleration. A full bridge converter composed of three arms vertically connected in series with a diode in reverse parallel to the switching element, a full bridge inverter sharing one arm with the full bridge converter, and a capacitor connected in parallel to the three arms; A series transformer in which an AC power source and a primary winding are connected in series and a secondary winding is connected in series from the output of the full bridge inverter through a reactor, and the main circuit control for controlling the full bridge converter and the full bridge inverter In a power saving device or a voltage stabilization device configured by a unit, the power generation means connected in parallel to the capacitor and the full bridge converter are controlled as a grid-connected inverter of the power generation means, and the single operation detection of the power generation means is detected System to generate disturbance signal for Control means, disturbance reduction control means for controlling the full-bridge inverter so that the disturbance signal is reduced, power storage means for temporarily storing generated power from the power generation means, and charging of the power storage means, or An isolated operation detection method comprising: charge / discharge means for performing discharge; and discharge acceleration detection means for accelerating and detecting isolated operation by changing a discharge amount from a power storage means when a disturbance signal increases by a certain amount. A full bridge converter composed of three arms vertically connected in series with a diode in reverse parallel to the switching element, a full bridge inverter sharing one arm with the full bridge converter, and a capacitor connected in parallel to the three arms; A series transformer in which an AC power source and a primary winding are connected in series and a secondary winding is connected in series from the output of the full bridge inverter through a reactor, and the main circuit control for controlling the full bridge converter and the full bridge inverter In a power saving device or a voltage stabilization device configured by a unit, the power generation means connected in parallel to the capacitor and the full bridge converter are controlled as a grid-connected inverter of the power generation means, and the single operation detection of the power generation means is detected System to generate disturbance signal for Control means, disturbance reduction control means for controlling the full-bridge inverter so that the disturbance signal is reduced, power storage means for temporarily storing generated power from the power generation means, and charging of the power storage means, or A power supply apparatus comprising: charge / discharge means for discharging; and discharge acceleration detection means for changing the amount of discharge from the power storage means when the disturbance signal increases by a certain amount to detect the single operation in an accelerated manner. 4. The grid interconnection control means includes frequency disturbance generation means for generating a disturbance in frequency, and the disturbance reduction control means includes frequency disturbance reduction means for reducing frequency disturbance. The isolated operation detection method described. 5. The system interconnection control means includes frequency disturbance generation means for generating disturbances in frequency, and the disturbance reduction control means includes frequency disturbance reduction means for reducing frequency disturbances. The power supply described. The grid interconnection control means includes current amplitude disturbance generation means for generating disturbance in the current amplitude, and the disturbance reduction control means includes current amplitude disturbance reduction means for reducing disturbance of the current amplitude. The isolated operation detection method according to 1 or 3. The grid interconnection control means includes current amplitude disturbance generation means for generating disturbance in the current amplitude, and the disturbance reduction control means includes current amplitude disturbance reduction means for reducing disturbance of the current amplitude. 5. The power supply device according to 2 or 4. The grid interconnection control means includes a current phase disturbance generation means for generating a disturbance in the current phase, and the disturbance reduction control means includes a current phase disturbance reduction means for reducing the disturbance of the current phase. The isolated operation detection method according to 1 or 3. The grid interconnection control means includes a current phase disturbance generation means for generating a disturbance in the current phase, and the disturbance reduction control means includes a current phase disturbance reduction means for reducing the disturbance of the current phase. 5. The power supply device according to 2 or 4. The islanding operation detection method according to any one of claims 1, 3, 5, 7, and 9, wherein the islanding operation is detected by a capacitor voltage fluctuation detecting means for detecting a voltage drop or rise of the capacitor. The power supply apparatus according to any one of claims 2, 4, 6, 8, and 10, wherein the isolated operation is detected by a capacitor voltage fluctuation detecting means for detecting a voltage drop or rise of the capacitor.

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