The direct current common network control device that a kind of photovoltaic generation is usedTechnical field
The present invention relates to the photovoltaic generation application, particularly a kind of with the control device of civil power as power backup and the application of photovoltaic electric power common network.
Background technology
Current photovoltaic generation application development is very rapid, and present application system mode mainly contains from two kinds of net type and grid types; As if be divided into two kinds of DC application and AC applications again by its load form.
Mainly be made up of photovoltaic cell, controller, storage battery from net type application system, promptly daytime, photovoltaic generation electric power was by battery stores, night when electricity consumption (or need), by storage battery as the use that powers to the load of system's power backup.When load was AC load, this system also comprised inverter.
The grid type application system mainly is made up of photovoltaic cell, controller, combining inverter, and promptly photovoltaic generation is directly surfed the Net, and enters municipal electrical network unified allocation of resources and uses, and the large-sized photovoltaic power station all is this application forms at present.
Occur a kind of photovoltaic generation in addition at present again in the user side application mode that is incorporated into the power networks, promptly photovoltaic electric power is after inversion, and the running status of strict tracking civil power power distribution network adds at user's application side, powers to the load simultaneously with civil power.Be the municipal safe operation of electric network that guarantees to be incorporated into the power networks with it, require this system implementation strict protection to prevent that " island effect " takes place.
Summary of the invention
The purpose of this invention is to provide the direct current common network control device that a kind of photovoltaic generation is used, is a kind of control device that photovoltaic electric power and civil power direct current common network are used.
The technical scheme that adopts is:
The direct current common network control device that a kind of photovoltaic generation is used comprises the unit that confluxes, civil power access unit and control unit, and its structure chart as shown in Figure 1.
The unit that confluxes of the present invention; can insert the photovoltaic electric power of the direct voltage parameter unanimity on n road (n can equal 1); (standard is: 12VDC/24VDC/36VDC/48VDC/110VDC/220VDC/380VDC) to conflux to become the direct current power that can satisfy the DC load need for electricity by the protection diode; be electrically connected with city through the identical electric pressure of transformation rectification, to direct current with the power supply of electric loading common network.
Civil power access unit of the present invention is that the civil power transformation is rectified into and the corresponding to dc power supply of system's utilization voltage, is connected together with photovoltaic generation after confluxing and powers to DC load.
Control principle of the present invention is: after photovoltaic generation direct current power voltage is a little more than the civil power direct current power voltage that inserts, system will preferentially use photovoltaic electric power to power to DC load.Otherwise when photovoltaic electric power is not enough, when promptly direct current photovoltaic electric power voltage is a little less than the civil power direct voltage that inserts, system will select to be powered to DC load by civil power automatically.
Control unit of the present invention is at first monitored the voltage parameter of each road photovoltaic generation, notes abnormalities, and sends and turn-offs this road photovoltaic generation instruction, and implement to turn-off.Monitor the voltage parameter of civil power simultaneously, find fault and unusual, send the shutoff control command immediately, implement turn-off protection through the transformation rectification.
Control unit workflow of the present invention as shown in Figure 2.
Control unit of the present invention, core are microcontroller chips that can satisfy high-speed sampling, are made up of it and correspondent peripheral circuit and device, can carry out the high-speed sampling computing to each associated voltage monitoring parameter.Be example to select the C8051F020 chip for use as control unit acp chip of the present invention now, circuit theory diagrams as shown in Figure 3.
Apparatus of the present invention are a kind of with the power backup of municipal electric power as the photovoltaic applications system, realize that photovoltaic electric power is safely and reliably to the DC load power applications.Characteristics are that the realization photovoltaic electric power " is promptly sent out promptly and used ", and system need not storage battery, and there is not the possibility that reverse power takes place in system, and reduces system cost and maintenance cost greatly, and the secondary pollution of avoiding storage battery to cause.
Description of drawings
Fig. 1 is the structure chart of direct current common network control device.
Fig. 2 is a workflow diagram of the present invention.
Fig. 3 is a control unit circuit principle master drawing.
Embodiment
The direct current common network control device that a kind of photovoltaic generation is used is made up of the unit that confluxes, civil power access unit and control unit.Wherein the acp chip of control unit is selected C8051F020 for use, and workflow is carried out according to the following steps, as shown in Figure 2:
Step 1, receive voltage parameter, receive from the voltage parameter of civil power through the transformation rectification from n road (n can equal 1) photovoltaic electric power.
Step 2, compare with every normal value of former setting.
Step 3, note abnormalities.Corresponding monitoring circuit is sent the shutoff instruction.
Step 4, enforcement are turn-offed.Every monitoring is proceeded.
Step 5, after monitoring parameter is normal, time-delay fixed value (1s-60s) is sent and is opened this road instruction, and implements open-minded to this road.
Move in circles with this.