JP2014220920A - Display panel for photovoltaic power generation system, and power conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power conditioner capable of making an owner confirm how much a power system voltage is suppressed by providing the display part of the detection value of the power system voltage, when a voltage sent out to the power system rises as the output power of an inverter increases in the power conditioner, and therefore, rise of the output voltage is suppressed by reducing the output power, if the detection voltage reaches a prescribed (determined in advance) upper limit value.SOLUTION: This power conditioner includes an output voltage suppressing part for detecting the output voltage of an inverter 13 to suppress the output voltage of the inverter 13 on the basis of the detection voltage so that the power system voltage does not exceed a prescribed upper value during linkage operation, and a display panel 15 for displaying the operation state of the output voltage suppressing part, and the detection value of the output voltage during suppression is visualized while suppressing operation is carried out.

Description

  The present invention relates to a display panel used in a power generation system such as solar power generation, and a power conditioner including the display panel.

  In paragraph 0009 of Cited Document 1, in a connected inverter that converts the direct current output of a solar cell into alternating current power and operates in an interconnected manner with a system distribution line, a detection unit that detects the output voltage of the inverter, and a detection voltage Based on the output voltage suppression unit that suppresses the output voltage of the inverter so that the system voltage does not exceed a predetermined upper limit during the interconnected operation, and a display unit that visualizes the period during which the output voltage suppression unit is suppressing And a connection type inverter device that displays an operating state of the output voltage suppression unit is disclosed. With this configuration, the user can know a period during which the inverter output voltage is suppressed.

JP-A-9-172784

  In the configuration of Patent Document 1, a general user (user) can confirm that the system voltage suppression function is operating, but cannot confirm the effect. For example, when the inverter output is unavoidably stopped beyond the limit of the system voltage suppression function, it has not been known how much the system voltage is suppressed by the reduction of the output power.

  In order to solve the above problems, in claim 1, a display panel used in a solar power generation system including a solar cell and a power conditioner that converts DC power output from the solar cell into AC power and outputs the AC power to a commercial system. The display panel is provided with first display means for indicating the suppression operation of the power conditioner and second display means for indicating the current power generation amount, and the power conditioner is suppressed. When operating in the mode, the display panel is characterized in that the first display means is in a suppression operation and the current power generation amount is displayed on the second display means.

  Moreover, in Claim 2, it is the power conditioner used with the solar power generation system which consists of a solar cell and the power conditioner which converts the direct-current power which this solar cell outputs into alternating current power, and outputs it to a commercial system, A DC-DC converter that receives the output power of the solar cell and outputs DC power, an inverter that converts DC power output by the DC-DC converter into AC power, and an output voltage that detects the output voltage of the inverter A detection unit, an output voltage suppression unit that suppresses the output voltage of the inverter so that the system voltage does not exceed a predetermined upper limit value during grid operation, and the output voltage suppression unit based on the voltage detected by the detection unit; And a display panel for displaying a detection value of the output voltage detector while the output voltage of the inverter is being suppressed.

During the operation of the output voltage suppression function, the system voltage suppression effect can be visualized.

The figure which shows the circuit structure of the power conditioner of Example 1. FIG. Graph showing current-voltage characteristics and current-power characteristics of solar cells The graph which shows the time change of the voltage of Example 1, and electric power. PAD diagram for determining system voltage rise abnormality of the first embodiment The figure which shows the display panel of Example 1. FIG. The figure which shows the display panel of the power conditioner of Example 2. The figure which shows the display panel of the power conditioner of Example 3.

  Embodiments of the present invention will be described with reference to the drawings.

  The power conditioner of Example 1 is demonstrated using FIGS. FIG. 1 shows a solar power generation system including the power conditioner according to the first embodiment, in which 1 is a power conditioner, 11 is a solar cell panel, and 14 is a commercial system. The power conditioner 1 includes a DC-DC converter 12 and an inverter 13, and a display panel 15 is connected to the power conditioner 1.

  As shown here, both ends of the solar cell panel 11 are connected to the input terminal of the DC-DC converter 12, and the output terminal of the DC-DC converter 12 is connected to the input terminal of the inverter 13. The output terminal of the inverter 13 is connected to an external single-phase three-wire commercial system 14. Further, the display panel 15 is connected to the inverter 13, and various display means such as LEDs and liquid crystal display elements can be used.

  The DC-DC converter 12 has a control that always follows the maximum power point (hereinafter, “maximum power point tracking control”) from the characteristics of the solar cell shown in FIG. 2. In FIG. 2, the solid line is a graph showing the characteristics of the output current Ipv and the output voltage Vpv of the solar cell (hereinafter, “current-voltage characteristics”), and the broken line is the characteristics of the output current Ipv and the output power Ppv of the solar cell (hereinafter “ It is a graph which shows a current-power characteristic "). As shown here, the current-voltage characteristic is a non-linear characteristic in which the output current Ipv becomes the short-circuit current Isc when the output voltage Vpv is 0, and the output current Ipv becomes 0 when the output voltage Vpv is the open circuit voltage Voc. is there. Further, the current-power characteristic has a characteristic that the output power Ppv becomes the maximum power point Pmax when the output current Ipv is Ipmax, and the output voltage Vpv at the maximum power point Pmax is Vpmax.

  The DC-DC converter 12 outputs the power obtained by the maximum power point tracking control to the inverter 13. The inverter 13 is connected to the commercial system 14 and outputs AC power. Signal lines are connected to the inverter 13 from both voltage lines U and V and a neutral line O to monitor the voltage.

  In the inverter 13, the neutral line and U-phase line voltage Vu-o and the neutral line and V-phase line voltage Vv-o are detected. When either the detected system voltage Vu-o or Vv-o reaches a predetermined (for example, predetermined) upper limit value Vres, the output power is reduced to suppress an increase in the system voltage, but the system voltage is the upper limit. While the value is reached, the LED of the display panel 15 is turned on to display the operation status of the system voltage rise suppression function. Further, the detected value of Vu-o or Vv-o detected is visualized on the display panel 15.

  Next, the operation of the system voltage rise suppression function will be described. FIG. 3 is a diagram showing operation waveforms of the system voltage rise suppression function with the horizontal axis as time. In order from the top, the operation mode of the inverter 1, the waveform of the neutral wire O and U-phase voltage Vu-o, or the neutral wire O and V-phase voltage Vv-o, the inverter 13 to the commercial system 14 The power output to

  In the steady mode, the DC-DC converter 12 is controlled so as to obtain the power at the maximum power point of the solar battery panel 11 and outputs it to the inverter 13. During operation in steady mode, when Vu-o or Vv-o reaches the upper limit value Vres, the operation mode is switched to the suppression mode.

  In the suppression mode, the DC-DC converter 12 is controlled so as to obtain electric power gradually reduced from the maximum power point from the solar cell panel 11 and outputs the electric power to the inverter 13 to suppress the output power of the inverter 13. By controlling the output power of the inverter 13, the system voltage is controlled so as not to exceed the upper limit value Vres. When Vu-o or Vv-o falls below the upper limit value Vres, the suppression mode is switched to the steady mode. At this time, the DC-DC converter 12 performs control so as to obtain the output power at the maximum power point of the solar cell panel 11 again and outputs it to the inverter 13.

  FIG. 4 is a PAD diagram showing the processing contents of the system voltage rise determination of the inverter 13. In FIG. 4, when the system voltage increase determination is started, first, the operation mode and the state of the system voltage are determined. In the suppression mode, when the system voltage reaches the upper limit value Vres, the suppression operation is continued and the suppression operation state and the system voltage detection value are displayed on the display panel 15. When the system voltage falls below the upper limit value Vres during the suppression mode, the operation mode is switched to the steady mode, and the display of the suppression operation state and the system voltage detection value on the display panel 15 is cancelled. When the operation mode is the steady mode and the system voltage reaches the upper limit value Vres, the display panel 15 notifies the system voltage rise abnormality, switches the operation mode to the suppression mode, displays the suppression operation state, and starts the suppression operation. To do.

  FIG. 5 is a diagram illustrating a configuration example of the display panel 15 of the power conditioner 1. The display panel 15 is connected to the inverter 13 and can remotely display the operation status of the inverter.

  In FIG. 5, 51 is a connection LED that is turned on during the connection operation, 52 is a self-supporting LED that is turned on during the independent operation, 53 is a suppression LED that is turned on during the suppression operation, and 54 is an error code when there is an abnormality in the power conditioner. 7 segment LED, 55 is a 7 segment LED for displaying the system voltage detection value during the system voltage rise suppression operation, 56 is a 7 segment LED for displaying the amount of power generation, etc., 57 is a 7 segment LED 56 for displaying the integrated power amount The accumulated power amount LED 58 that is sometimes lit is a generated power amount LED 58 that is lit when the 7-segment LED 56 displays the generated power amount.

  During the stop, the connection LED 51, the self-supporting LED 52, and the suppression LED 53 are turned off. At this time, the 7 segment 56 may display information indicating that it is stopped.

  In the steady mode, the grid LED 51 is lit, and the current power generation amount (= output power) is displayed on the 7-segment LED 56.

  In the suppression mode, the connection LED 51 and the suppression LED 53 are lit, an abnormality code for notifying the abnormality content to the 7-segment LED 54, the system voltage detection value on the 7-segment LED 55, and the current power generation amount (= output power) on the 7-segment LED 56 are displayed. To do. Thereby, the detected value of the output voltage can be visualized during the suppression operation, and the effect of the suppression mode can be confirmed.

  When the power supply voltage exceeds a predetermined (for example, predetermined) upper limit value when the inverter 13 is in a connected operation by turning on or blinking the suppression LED 53, the output suppression function is activated. A case where the output power is suppressed by a temperature rise caused by continuous operation may be distinguished.

  Example 2 will be described with reference to FIG. Note that the description of the points in common with the first embodiment will be omitted.

  The difference between the first embodiment and the present embodiment is that the display panel 15 is incorporated in the power conditioner body. With such a configuration, it is possible to simultaneously check the operation state of the power conditioner and the connection state of the wiring, and it becomes easy to identify an abnormality.

  Example 3 will be described with reference to FIG. Note that description of points in common with the first or second embodiment will be omitted.

  FIG. 7 is also a configuration diagram of a power conditioner in which the display panel 15 is incorporated as in the second embodiment. In FIG. 7, reference numeral 71 denotes a 7-segment LED that displays the accumulated power amount, the generated power amount, the abnormal content, and the system voltage detection value. As a difference between the second embodiment and the present embodiment, the display panel 15 does not have an abnormal code display portion and a display portion of a system voltage detection value to be displayed at the time of system voltage increase suppression operation, and all information is displayed on the 7-segment LED 71. A point is mentioned.

  With such a configuration, only necessary information can be displayed when necessary for a general user (user).

  In the present embodiment, during the system voltage rise suppression operation, the 7-segment LED 71 can alternately display the generated power amount and the examination voltage detection value at regular intervals. In addition, when an abnormality occurs, an abnormal code can be displayed for a certain period of time.

1: Power conditioner 11: Solar cell panel 12: DC-DC converter 13: Inverter 14: Commercial system 15: Display panel 51: Interconnection LED
52: Independent LED
53: Suppression LED
54: 7 segment LED
55: 7 segment LED
56: 7 segment LED
57: Integrated power LED
58: Power generation amount LED
71: 7 segment LED

Claims (3)

A display panel used in a solar power generation system including a solar cell and a power conditioner that converts DC power output from the solar cell into AC power and outputs the AC power to a commercial system,
The display panel is provided with first display means for indicating the suppression operation of the power conditioner and second display means for indicating the current amount of generated power,
A display panel, wherein when the power conditioner is operating in a suppression mode, the first display means is in a suppression operation, and the second display means displays a current amount of generated power. A power conditioner used in a solar power generation system including a solar battery and a power conditioner that converts the direct current power output from the solar battery into alternating current power and outputs the alternating current power,
A DC-DC converter that receives the output power of the solar cell and outputs DC power;
An inverter that converts DC power output from the DC-DC converter into AC power;
An output voltage detector for detecting the output voltage of the inverter;
Based on the voltage detected by the detection unit, an output voltage suppression unit that suppresses the output voltage of the inverter so that the system voltage does not exceed a predetermined upper limit value during grid operation,
While the output voltage suppression unit suppresses the output voltage of the inverter, a display panel that displays the detection value of the output voltage detection unit;
A power conditioner comprising: The power conditioner according to claim 2,
The power conditioner is characterized in that the display panel displays that the operation is a suppression operation while the output voltage suppression unit suppresses the output voltage of the inverter.