CN116014798B - Control circuit, parallel control circuit and energy storage inverter system thereof - Google Patents
Control circuit, parallel control circuit and energy storage inverter system thereof Download PDFInfo
- Publication number
- CN116014798B CN116014798B CN202310049047.6A CN202310049047A CN116014798B CN 116014798 B CN116014798 B CN 116014798B CN 202310049047 A CN202310049047 A CN 202310049047A CN 116014798 B CN116014798 B CN 116014798B
- Authority
- CN
- China
- Prior art keywords
- energy storage
- feedback
- control
- circuit
- resistor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/50—Photovoltaic [PV] energy
- Y02E10/56—Power conversion systems, e.g. maximum power point trackers
Abstract
The embodiment of the invention discloses a control circuit, a parallel control circuit and an energy storage inverter system thereof, wherein the control circuit comprises: a switching circuit configured to output a feedback voltage and a start voltage to the feedback circuit and the transmitter, respectively, in response to the control switch state; a feedback circuit configured to output a control signal to the controller in response to the feedback voltage; a protection circuit configured to filter noise energy of the starting voltage and store electric energy when the switching circuit outputs the starting voltage, and to provide a freewheel loop for the transmitter when the switching circuit stops outputting the starting voltage; when the feedback circuit receives the feedback voltage, the control signal is in a low level; when the feedback circuit does not receive the feedback voltage, the control signal is high. By the mode, the photovoltaic module or other safety-related protection circuits can be rapidly turned off to keep the energy storage inverter in the working state, and the operation efficiency of the energy storage inverter system is improved.
Description
Technical Field
The embodiment of the invention relates to the technical field of electronics, in particular to a control circuit, a parallel control circuit and an energy storage inverter system thereof.
Background
In order to further accelerate the steps of carbon reaching peak and carbon neutralization and promote the construction of a power system taking new energy as a main body, people have given high expectations to the efficient utilization of green clean energy. The energy storage inverter system is used as a clean energy conversion and storage device, is rapidly developed in the global scope in recent years, and lays a foundation for realizing green low-carbon sustainable development. With the popularity of energy storage inverter systems, the problem of safe power usage becomes particularly important. When the direct current side of the photovoltaic system fails or a fire occurs, the direct current side still has high voltage of hundreds of volts. If the direct current high voltage can not be turned off, not only the personal and property of residents are lost, but also fire fighters are exposed to electric shock risks when going to the roof for maintenance. Related countries and regions require that the photovoltaic system must have a Rapid Shutdown (RSD) function, and the photovoltaic system should reduce the voltage of the photovoltaic module within a specified distance of a specified time to a safe voltage.
The traditional quick turn-off principle is: when the power grid is powered off, the transmitter does not send a maintenance on signal to the receiver due to the fact that power supply is lost, the receiver cannot receive the maintenance on signal within a period of time, and the PV assembly is turned off; when the power grid resumes the power supply, the transmitter sends the turn-on signal, and the receiver closes the switch after receiving the turn-on signal, resumes photovoltaic system and generates electricity. For a photovoltaic power generation system, the rapid shutdown method is very effective. For the photovoltaic energy storage power supply system, if a fire disaster or an electric shock occurs to a person in the photovoltaic module, the traditional shutdown method can realize system-level emergency shutdown. However, when maintenance personnel periodically roof the photovoltaic module for maintenance, it is not necessary to shut down the entire energy storage inverter system. The traditional turn-off method has the advantages that the whole energy storage inverter system is completely turned off after the power grid is powered off, the key load loses power supply, and the emergency power supply advantage of the energy storage inverter system cannot be fully exerted. In addition, as the load grows, a single energy storage inverter cannot meet the requirements of high-power household loads, and multiple inverters are often required to be connected in parallel to increase the system capacity. The load is not the maximum value at all times, and when the load is lighter, the loss of the inverter is increased, which not only causes the inefficiency of the whole system, but also reduces the service life of the inverter.
Disclosure of Invention
In order to solve the technical problems, one technical scheme adopted by the embodiment of the invention is as follows: there is provided a control circuit for use in a photovoltaic energy storage inverter system comprising a controller for controlling the inverter and a transmitter for controlling a photovoltaic module, the control circuit comprising a switching circuit, a feedback circuit and a protection circuit, wherein,
the switching circuit comprises a first voltage source, a second diode, a current protector, a first control switch and a second control switch, wherein the electric energy output end of the first voltage source is connected to the anode of the second diode, the cathode of the second diode is connected to the first end of the current protector, and the second end of the current protector is connected to the first end of the first control switch; the second end of the first control switch is connected to the first end of the second control switch to form a first connection point; when the first control switch is closed, the first connection point outputs feedback voltage to the feedback circuit; when the first control switch and the second control switch are simultaneously closed, the second end of the second control switch outputs starting voltage to the transmitter; the feedback circuit is configured to output a control signal to the controller in response to the feedback voltage; the protection circuit is electrically connected to the switching circuit, and is configured to filter noise energy of the starting voltage and store electric energy when the starting voltage is output by the switching circuit, and provide a freewheel loop for the transmitter when the starting voltage is stopped from being output by the switching circuit; when the feedback circuit receives the feedback voltage, the control signal is at a low level; when the feedback circuit does not receive the feedback voltage, the control signal is high level.
In some embodiments, the current protector comprises a fuse or a protection resistor.
In some embodiments, the feedback circuit comprises a second voltage source, a triode, a feedback resistor, a divider resistor, a pull-up resistor, a matching resistor and a filter capacitor, wherein a first end of the feedback resistor is connected to the first connection point, and a second end of the feedback resistor is respectively connected with a base electrode of the triode and a first end of the divider resistor; the collector of the triode is respectively connected to the first end of the pull-up resistor and the first end of the matching resistor, and the emitter of the triode is grounded; the electric energy output end of the second voltage source is connected to the second end of the pull-up resistor, the second end of the matching resistor is connected to the first end of the filter capacitor to form a second connection point, and the second connection point is used for outputting the control signal; and the second end of the filter capacitor and the second end of the divider resistor are both connected to the emitter of the triode.
In some embodiments, the protection circuit comprises a first diode and a storage capacitor, wherein a cathode of the first diode is connected to a second end of the second control switch, and an anode of the first diode is grounded; the energy storage capacitor is connected in parallel with two ends of the first diode and is used for outputting the starting voltage to the transmitter.
In order to solve the technical problems, another technical scheme adopted by the embodiment of the invention is as follows: there is provided a photovoltaic energy storage inverter system, the system comprising: the photovoltaic power generation system comprises a photovoltaic module, a receiver, a transmitter, an energy storage inverter, a relay, a controller, a load, a power grid and one control circuit, wherein the control circuit responds to a control switch state and respectively outputs starting voltage and control signals to the transmitter and the controller; the controller responds to the level of the control signal to control the relay, and when the control signal is at a low level, the relay is controlled to be closed; when the control signal is at a high level, the relay is controlled to be disconnected; the relay is arranged between the energy storage inverter and the load; the transmitter outputting a sustain-on signal to the receiver in response to the start-up voltage; the receiver is arranged between the photovoltaic module and the energy storage inverter, responds to the maintenance on signal to maintain the conduction between the photovoltaic module and the energy storage inverter, and if the receiver does not receive the maintenance on signal, the connection between the photovoltaic module and the energy storage inverter is disconnected; the power grid is connected to the load, the power grid being configured to power the load when the relay is open.
In order to solve the technical problems, another technical scheme adopted by the embodiment of the invention is as follows: there is provided a parallel control circuit applied to a parallel energy storage inverter system including n+1 controllers and n+1 energy storage inverters, the circuit comprising: a switching circuit and n+1 feedback circuits, wherein the switching circuits are respectively connected to the n+1 feedback circuits, the switching circuits being configured to respectively output feedback voltages to the respective feedback circuits in response to a switching state; the switching circuit comprises a first voltage source, a second diode, a fuse and N+1 control switches, wherein the electric energy output end of the first voltage source is connected to the anode of the second diode, the cathode of the second diode is connected to the first end of the fuse, and the second end of the fuse is connected to the first end of the first control switch; the N+1 control switches are sequentially connected end to form corresponding N connection points, the second end of the first control switch is connected to the first end of the second control switch to form a first connection point, and the second end of the N control switch is connected to the first end of the N+1 control switch to form an N connection point; when the continuous M control switches including the first control switch are all closed, the first connecting point to the Mth connecting point respectively output corresponding starting voltages; the feedback circuit is configured to output a control signal to a respective controller in response to the feedback voltage to control the respective energy storage inverter to start or shut down; when the feedback circuit receives the feedback voltage, the control signal is at a low level; when the feedback circuit does not receive the feedback voltage, the control signal is high level.
In some embodiments, the feedback circuit comprises a second voltage source, a triode, a feedback resistor, a voltage dividing resistor, a pull-up resistor, a matching resistor and a filter capacitor, wherein a first end of the feedback resistor is connected to a second end of a corresponding control switch, and the second end of the feedback resistor is respectively connected with a base electrode of the triode and the first end of the voltage dividing resistor; the collector of the triode is respectively connected to the first end of the pull-up resistor and the first end of the matching resistor, and the emitter of the triode is grounded; the electric energy output end of the second voltage source is connected to the second end of the pull-up resistor, the second end of the matching resistor is connected to the first end of the filter capacitor to form a signal output point, and the signal output point is used for outputting the control signal; and the second end of the filter capacitor and the second end of the divider resistor are both connected to the emitter of the triode.
In order to solve the technical problems, another technical scheme adopted by the embodiment of the invention is as follows: providing a parallel energy storage inverter system comprising n+1 controllers, n+1 energy storage inverters, n+1 relays, a load, a power grid and a parallel control circuit as described above, wherein the power output of the power grid is connected to the load; the parallel control circuit responds to the control switch state and respectively outputs corresponding control signals to corresponding controllers; the controller responds to the level of the control signal to control the corresponding energy storage inverter, and when the control signal is at a low level, the controller controls the energy storage inverter to start; when the control signal is at a high level, the energy storage inverter is controlled to be closed; the output ends of the N+1 energy storage inverters are connected to one end of the corresponding relay; the other ends of the N+1 relays are electrically connected to the load, and when any relay is closed and the corresponding energy storage inverter is in a starting state, the energy storage inverter supplies power to the load.
The beneficial effects of the embodiment of the invention are as follows: compared with the prior art, the control circuit provided by the embodiment of the invention effectively solves the defects of the traditional turn-off method, and the circuit realizes the function of rapidly turning off a photovoltaic module or other safety-related protection circuits to keep the energy storage inverter in a working state by introducing a priority control and feedback control mechanism. The purpose that a user can still obtain power supply by means of a battery during the period of repairing the photovoltaic panel by an operation and maintenance person on the roof is achieved, and the operation efficiency of the energy storage inverter system is improved. The priority control realizes the function of turning off the whole photovoltaic energy storage system by one key under dangerous emergency, improves the safety of the energy storage inverter system, realizes the priority control of the turned-off equipment, and selectively turns off according to the requirement of a user. In addition, the parallel control circuit which is properly modified based on the control circuit can be applied to the parallel operation application scene of the energy storage inverter, and a user can reasonably configure the number of the energy storage inverters put into parallel operation according to the load size, so that the problems of single parallel operation mode, redundancy in parallel operation and low operation efficiency of the traditional inverter are solved.
Drawings
Fig. 1 is a schematic structural diagram of a control circuit according to an embodiment of the present invention;
FIG. 2 is a circuit topology of a control circuit according to an embodiment of the present invention;
fig. 3 is a schematic structural diagram of a photovoltaic energy storage inverter system according to an embodiment of the present invention;
FIG. 4 is a schematic diagram of a parallel control circuit according to an embodiment of the present invention;
FIG. 5 is a circuit topology of a parallel control circuit according to an embodiment of the present invention;
fig. 6 is a schematic structural diagram of a parallel energy storage inverter system according to an embodiment of the present invention.
Detailed Description
Fig. 1 is a schematic structural diagram of a control circuit according to an embodiment of the present invention, where the control circuit is applied to a photovoltaic energy storage inverter system, the photovoltaic energy storage inverter system includes a controller for controlling an inverter and a transmitter for controlling a photovoltaic module, the control circuit includes a switching circuit 100, a feedback circuit 200 and a protection circuit 300,
a switching circuit 100 is electrically connected to the feedback circuit 200, the switching circuit 100 being configured to output a feedback voltage and a start voltage to the feedback circuit 200 and the transmitter 30, respectively, in response to controlling the switching state.
The feedback circuit 200 is configured to output a control signal to the controller 20 in response to the feedback voltage.
The protection circuit 300 is electrically connected to the switching circuit 100, the protection circuit 300 being configured to filter out noise energy of the starting voltage and store electrical energy when the switching circuit 100 outputs the starting voltage, and to provide a freewheel loop for the transmitter 30 when the switching circuit 100 stops outputting the starting voltage.
When the feedback circuit 200 receives the feedback voltage, the control signal is low; when the feedback circuit 200 does not receive the feedback voltage, the control signal is high.
In some embodiments, the circuit topology of the control circuit is shown in fig. 2, wherein the switching circuit 100 comprises a first voltage source VCC, a second diode D2, a current protector, a first control switch S1 and a second control switch S2.
In this embodiment, the current protector is a fuse FU. Other types of components, such as a resistor with a value of 0, may also be selected for the current protector, and the type of the current protector is not limited herein. The current protector may be fused to protect the control circuit from being burned out when the current is excessive.
In this embodiment, the first control switch S1 and the second control switch S2 are all three-contact mechanical switches, where the three-contact mechanical switches include a common terminal, a normally closed contact and a normally open electric shock, and two-contact mechanical switches may be selected, and the types of the control switches are not limited herein.
It should be noted that, when the photovoltaic energy storage inverter system is operating normally, the first control switch S1 and the second control switch S2 are both in a closed state. For a three-contact mechanical switch, then the common terminal is connected to the normally closed contact by default.
The feedback circuit 200 includes a second voltage source VDD, a triode Q1, a feedback resistor R1, a voltage dividing resistor R2, a pull-up resistor R3, a matching resistor R4, and a filter capacitor C2.
The protection circuit 300 includes a first diode D1 and a storage capacitor C1.
Specifically, the power output end of the first voltage source VCC is connected to the anode of the second diode D2, the cathode of the second diode D2 is connected to the first end of the fuse FU, and the second diode D2 is used for preventing the load from reversely charging current to the first voltage source VCC, so as to play a role of a protection circuit. The second terminal of the fuse FU is connected to the first terminal of the first control switch S1, i.e., the common terminal of the first control switch S1.
In this embodiment, the output voltage of the first voltage source VCC is 12 vdc.
The second terminal of the first control switch S1 is connected to the first terminal of the second control switch S2 to form a first connection point a.
When the first control switch S1 is closed, the first connection point a outputs a feedback voltage.
When the first control switch S1 and the second control switch S2 are simultaneously closed, the second terminal of the second control switch S2 outputs the start voltage.
The first control switch S1 and the second control switch S2 are connected in series to realize a logical and function, and when the common terminal of any switch of the first control switch S1 and the second control switch S2 is connected to the normally open contact, the second control switch S2 cannot output the starting voltage.
The first end of the feedback resistor R1 is connected to the first connection point A, and the second end of the feedback resistor R1 is respectively connected with the base electrode of the triode Q1 and the first end of the divider resistor R2. The resistor values of the feedback resistor R1 and the voltage dividing resistor R2 are properly configured, so that the triode Q1 can work in a switching state.
The collector of the triode Q1 is respectively connected to the first end of the pull-up resistor R3 and the first end of the matching resistor R4, and the emitter of the triode Q1 is grounded.
The pull-up resistor R3 needs to be selected in a compromise between the power consumption and the feedback delay of the feedback circuit 200, and the low power consumption and the rapidity cannot be satisfied at the same time.
The power output end of the second voltage source VDD is connected to the second end of the pull-up resistor R3, the second end of the matching resistor R4 is connected to the first end of the filter capacitor C2 to form a second connection point Y, and the second connection point Y is used for outputting a control signal.
In this embodiment, the output voltage of the second voltage source VDD is 3.3V dc voltage.
The second end of the filter capacitor C2 and the second end of the divider resistor R2 are both connected to the emitter of the transistor Q1.
The matching resistor R4 and the filter capacitor C2 form a group of RC filters to reduce high-frequency noise and edge overshoot of the starting voltage. The matching resistor R4 and the filter capacitor C2 need to be matched with the pull-up resistor R3 to ensure that a proper time constant is selected. The interconnection point of the matching resistor R4 and the filter capacitor C2 is used as a starting voltage Output end of the feedback circuit 200, the starting voltage Output end is connected with one of the IO (Input and Output) ports of the controller 20, and the controller 20 processes the signal to perform a corresponding action.
The cathode of the first diode D1 is connected to the second end of the second control switch S2, and the anode of the first diode D1 is grounded.
The energy storage capacitor C1 is connected in parallel to two ends of the first diode D1, and the energy storage capacitor C1 is configured to output the starting voltage to the transmitter 30.
Specifically, the energy storage capacitor C1 is connected across the positive electrode and the negative electrode of the transmitter 30, where the energy storage capacitor C1 is used to filter noise of the output voltage of the first voltage source VCC, and store energy at the same time, and when the load 80 of the transmitter 30 is excessively high in current, the energy storage capacitor C1 discharges to avoid controlling the voltage of the first voltage source VCC to drop greatly.
The first diode D1 functions to provide a freewheel circuit for the transmitter 30 when the first control switch S1 and/or the second control switch S2 are turned off, preventing high voltage damage to the devices at both the positive and negative terminals of the transmitter 30.
Based on one of the control circuits 10 described above, the embodiment of the present application provides a photovoltaic energy storage inverter system, whose schematic structural diagram is shown in fig. 3, and the photovoltaic energy storage inverter system includes a photovoltaic module 70, a receiver 60, a transmitter 30, an energy storage inverter 50, a relay 40, a controller 20, a load 80, a power grid 90 and one of the control circuits 10 described above, wherein,
the control circuit 10 outputs a start voltage and a control signal to the transmitter 30 and the controller 20, respectively, in response to the control switch state, the controller 20 controls the relay 40 in response to the level of the control signal, and when the control signal is at a low level, the relay 40 is controlled to be closed; when the control signal is high, the control relay 40 is turned off. Relay 40 is disposed between energy storage inverter 50 and load 80.
The transmitter 30 outputs a sustain-on signal to the receiver 60 in response to the start voltage; the receiver 60 is disposed between the photovoltaic module 70 and the energy storage inverter 50, the receiver 60 maintains conduction between the photovoltaic module 70 and the energy storage inverter 50 in response to the maintenance conduction signal, and if the receiver 60 does not receive the maintenance conduction signal, the connection between the photovoltaic module 70 and the energy storage inverter 50 is disconnected; the power grid 90 is connected to the load 80, the power grid 90 being used to power the load 80 when the relay 40 is open.
The principle of operation of the control circuit 10 in the photovoltaic energy storage inverter system is described as follows:
the first control switch S1 can realize the function of emergency stop and has the highest priority; the second control switch S2 may implement the function enabled by the transmitter 30 with a higher priority. There are two switch status bits, with 0 indicating open and 1 indicating closed, and there are four switch status as shown in the following table.
When the photovoltaic energy storage inverter system is not required to work, the first control switch S1 and the second control switch S2 are respectively in an off state, and even if the common terminal is connected to the normally open contact, the system is in a mode 1. Since the second control switch S2 is turned off, the power supply to the transmitter 30 is interrupted, the receiver 60 does not receive the signal to maintain the on state, the photovoltaic module 70 is turned off, and the relay 40 is also turned off. The energy storage inverter 50 is not electrified under the condition of no external power supply, so that the personal safety of installation and operation staff during operation can be ensured.
When the photovoltaic energy storage inverter system is required to work normally, the first control switch S1 and the second control switch S2 are in a closed state, even if the common terminal is connected to a normally closed contact, i.e. the system is in mode 4. Only when both switches are simultaneously closed, the first voltage source VCC can supply power to the transmitter 30, and the receiver 60 can put the photovoltaic module 70 into operation upon receipt of the maintain on signal. After the first control switch S1 is closed, the potential at the point a is at a high level, the driving triode Q1 is turned on, the matching resistor R4 is pulled down to the ground, and the potential at the second connection point Y is at a low level. When the controller 20 detects that the voltage of the photovoltaic module 70 is a certain value and the IO of the controller 20 connected to the second connection point Y is at a low level, the controller 20 knows that the photovoltaic module 70 is normally connected and the first control switch S1 is in the closed state, so as to control the energy storage inverter 50 to enter the normal working mode.
When the photovoltaic energy storage inverter system is required to work normally, the first control switch S1 and the second control switch S2 are required to be in a normally closed state. However, assuming that the photovoltaic module 70 requires maintenance, the user does not want to shut down the energy storage inverter system when the photovoltaic module 70 is shut down. At this time, the first control switch S1 and the second control switch S2 may be opened to close, so that only the photovoltaic module 70 may be turned off, which is the mode 3. Because the first control switch S1 has a higher priority than the second control switch S2, turning off the first control switch S1 necessarily causes the power of the transmitter 30 to be interrupted, so that the photovoltaic module 70 is turned off quickly. Meanwhile, the first connection point a is still at a high level, the second connection point Y is at a low level, the IO of the controller 20 receives the feedback voltage as the low level and detects that the voltage of the photovoltaic module 70 is 0, the controller 20 knows that the direct current input of the photovoltaic module 70 is cut off and the shutdown signal is invalid, the working state of the energy storage inverter 50 is switched to the battery to supply power to the load 80, the function of turning off the photovoltaic module 70 is realized, and the safety, the power supply reliability and the efficiency of the energy storage inverter system are improved.
When the energy storage inverter system works normally, the first control switch S1 and the second control switch S2 are in a normally closed state. If an emergency situation, such as an electric shock, fire, etc., is encountered, the photovoltaic module 70 and the energy storage inverter 50 may be simultaneously turned off by turning on the first control switch S1. After the first control switch S1 is turned on, the energy storage inverter system enters the mode 2, the first connection point a jumps from a high level to a low level, and the second connection point Y jumps from a low level to a high level. After obtaining this information, the controller 20 turns off the driving signal of the power semiconductor device, and simultaneously turns off the relay 40 of the power grid 90 and the energy storage inverter 50, thereby realizing the function of emergency stop and ensuring the personal and property safety to the greatest extent.
Unlike the prior art, the control circuit 10 provided by the embodiment of the invention effectively solves the defects of the traditional shutdown method, and the circuit realizes the function of quickly shutting down the photovoltaic module 70 and keeping the energy storage inverter 50 in the working state by introducing a priority control and feedback control mechanism. The purpose that a user can still obtain power supply by means of a battery during the period of repairing the photovoltaic panel by an operation and maintenance person on the roof is achieved, and the operation efficiency of the energy storage inverter system is improved. The priority control realizes the function of turning off the whole photovoltaic energy storage system by one key under dangerous emergency, and improves the safety of the energy storage inverter system.
Based on the control circuit, according to the concept of the switching priority, the embodiment of the application also provides a parallel control circuit, which is applied to a parallel energy storage inverter system, wherein the parallel energy storage inverter system comprises n+1 controllers and n+1 energy storage inverters. The parallel control circuit includes: a switching circuit and n+1 feedback circuits, wherein the switching circuits are respectively connected to the n+1 feedback circuits, the switching circuits being configured to respectively output feedback voltages to the respective feedback circuits in response to the switching states; the feedback circuit is configured to output a control signal to the respective controller in response to the feedback voltage to control the respective energy storage inverter to start or shut down;
when the feedback circuit receives the feedback voltage, the control signal is at a low level; when the feedback circuit does not receive the feedback voltage, the control signal is high.
Based on the parallel control circuit, the switch circuit comprises a first voltage source, a second diode, a fuse and n+1 control switches, wherein the electric energy output end of the first voltage source is connected to the anode of the second diode, the cathode of the second diode is connected to the first end of the fuse, and the second end of the fuse is connected to the first end of the first control switch.
The N+1 control switches are sequentially connected end to form corresponding N connection points, the second end of the first control switch is connected to the first end of the second control switch to form a first connection point, and the second end of the N control switch is connected to the first end of the N+1 control switch to form an N connection point; when the continuous M control switches including the first control switch are all closed, the first connection point to the Mth connection point respectively output corresponding starting voltages.
Note that N is greater than or equal to 1, and m is less than or equal to N.
In the above-described parallel control circuit, n+1 feedback circuits are included, and it should be noted that these n+1 feedback circuits are all identical to those in the previous embodiment, i.e., the feedback circuits in the control circuit.
In this embodiment, 3 energy storage inverters and 3 controllers are taken as an example for explanation, and a schematic structural diagram thereof is shown in fig. 4. The parallel control circuit includes: switching circuit 400, feedback circuit 510, feedback circuit 520, and feedback circuit 530, wherein,
the switching circuits 400 are respectively connected to the feedback circuits 510, 520 and 530, and the switching circuits 400 are configured to respectively output feedback voltages to the respective feedback circuits in response to the switching states.
The feedback circuit is configured to output a control signal to the respective controller in response to the feedback voltage to control the respective energy storage inverter to start or shut down.
When the feedback circuit receives the feedback voltage, the control signal is at a low level; when the feedback circuit does not receive the feedback voltage, the control signal is high.
Note that, in this embodiment, the circuit structures of the feedback circuit 510, the feedback circuit 520, and the feedback circuit 530 are the same.
In this embodiment, a circuit topology diagram of the parallel control circuit is shown in fig. 5, wherein the switching circuit 400 includes a first voltage source VCC, a second diode D2, a fuse FU, a first control switch S1, a second control switch S2, and a third control switch S3.
The feedback circuit comprises a second voltage source VDD, a triode Q1, a feedback resistor R1, a divider resistor R2, a pull-up resistor R3, a matching resistor R4 and a filter capacitor C2.
The power output terminal of the first voltage source VCC is connected to the anode of the second diode D2, the cathode of the second diode D2 is connected to the first terminal of the fuse FU, and the second terminal of the fuse FU is connected to the first terminal of the first control switch S1.
The first control switch S1, the second control switch S2 and the third control switch S3 are sequentially connected end to form 2 connection points respectively, the second end of the first control switch S1 is connected to the first end of the second control switch to form a first connection point A1, and the second end of the second control switch S2 is connected to the first end of the third control switch S3 to form a second connection point A2.
When the first control switch S1, the second control switch S2 and the third control switch S3 are all closed, the first connection point and the second connection point output corresponding starting voltages respectively.
The first end of the feedback resistor R1 is connected to the second end of the corresponding control switch, and the second end of the feedback resistor R1 is respectively connected with the base electrode of the triode Q1 and the first end of the divider resistor R2; the collector of the triode Q1 is respectively connected to the first end of the pull-up resistor R3 and the first end of the matching resistor R4, and the emitter of the triode Q1 is grounded.
The electric energy output end of the second voltage source VDD is connected to the second end of the pull-up resistor R3, the second end of the matching resistor R4 is connected to the first end of the filter capacitor C2 to form a signal output point, and the signal output point is used for outputting a control signal; the second end of the filter capacitor C2 and the second end of the divider resistor R2 are both connected to the emitter of the transistor Q1.
Based on the above-mentioned parallel control circuit, the embodiment of the present application further provides a parallel energy storage inverter system, whose structure schematic diagram is shown in fig. 6, and also uses 3 energy storage inverters and a system formed by the same as an example for explanation, where the system includes a controller 210, a controller 220, a controller 230, an energy storage inverter 310, an energy storage inverter 320, an energy storage inverter 330, a relay 610, a relay 620, a relay 630, a load 80, a power grid 90, and a parallel control circuit 40 as above, where
The power output of the grid 90 is connected to the load 80; the parallel control circuit 40 outputs corresponding control signals to the controller 210, the controller 220, and the controller 230, respectively, in response to the control switch states.
The output ends of the controller 210, the controller 220 and the controller 230 are respectively connected to the input ends of the energy storage inverter 310, the energy storage inverter 320 and the energy storage inverter 330, the controller responds to the level of the control signal to control the corresponding energy storage inverter, and when the control signal is at a low level, the energy storage inverter is controlled to be started; when the control signal is at a high level, the energy storage inverter is controlled to be turned off.
The output terminals of the energy storage inverter 310, the energy storage inverter 320, and the energy storage inverter 330 are connected to one terminals of the relay 610, the relay 620, and the relay 630, respectively.
The other ends of relay 610, relay 620, and relay 630 are all electrically connected to load 80, and when any relay is closed, and the corresponding energy storage inverter is in a start-up state, the energy storage inverter powers load 80.
The principle of operation of the parallel control circuit 40 in the parallel energy storage inverter system is described as follows:
the state of the parallel control circuit constituted by three control switches is 8 in total, and Yi (i=1, 2, 3) is active high as shown in the following table, representing a shutdown.
When the parallel energy storage inverter system is in modes 1 to 4, the first control switch S1 is in the open position and the output combinations of feedback circuit 510, feedback circuit 520 and feedback circuit 530 are all 111. Because the priority of the first control switch S1 is highest, opening the first control switch S1 means that all energy storage inverters are shut down entirely. The working mode can be applied to maintenance and emergency stop of the energy storage inverter.
When the parallel energy storage inverter system is in mode 5 and mode 6, the output combination of feedback circuit 510, feedback circuit 520, and feedback circuit 530 is 011, regardless of whether third control switch S3 is open or not. Because of the higher priority of the second control switch S2, opening the second control switch S2 means turning off the energy storage inverter 320 and the energy storage inverter 330. When the electricity consumption of a user is small, the parallel energy storage inverter system can be selected to work in the mode, so that the system loss is reduced, the service life of the energy storage inverters is prolonged, the electric energy quality is improved, and the circulation risk caused by parallel operation of a plurality of energy storage inverters is reduced.
When the parallel energy storage inverter system is in mode 7, only the third control switch S3 is open and the outputs of feedback circuit 510, feedback circuit 520, and feedback circuit 530 combine to be 001. This indicates that energy storage inverter 330 is shut down, leaving only energy storage inverter 320 and energy storage inverter 310 running. When the electricity consumption of the user is not large, the working mode can be selected, and the operation efficiency of the energy storage inverter system can be improved.
When the method is popularized to the parallel connection of n energy storage inverters, a user can choose to put into proper energy storage inverters to operate in parallel according to the quantity of electricity consumption. The parallel control circuit has high flexibility and configurability, and can meet the power requirements of different users.
Compared with the prior art, the parallel control circuit which is properly modified based on the control circuit can be applied to the parallel operation application scene of the energy storage inverter, and a user can reasonably configure the number of the energy storage inverters put into parallel operation according to the load size, so that the problems of single parallel operation mode, parallel operation redundancy and low operation efficiency of the traditional inverter are solved.
The foregoing description is only of embodiments of the present invention, and is not intended to limit the scope of the invention, and all equivalent structures or equivalent processes using the descriptions and the drawings of the present invention or directly or indirectly applied to other related technical fields are included in the scope of the present invention.
Claims (8)
1. A control circuit applied to a photovoltaic energy storage inverter system, the photovoltaic energy storage inverter system comprises a controller for controlling an inverter and a transmitter for controlling a photovoltaic module, the control circuit is characterized by comprising a switch circuit, a feedback circuit and a protection circuit,
the switching circuit comprises a first voltage source, a second diode, a current protector, a first control switch and a second control switch, wherein the electric energy output end of the first voltage source is connected to the anode of the second diode, the cathode of the second diode is connected to the first end of the current protector, and the second end of the current protector is connected to the first end of the first control switch; the second end of the first control switch is connected to the first end of the second control switch to form a first connection point;
when the first control switch is closed, the first connection point outputs feedback voltage to the feedback circuit; when the first control switch and the second control switch are simultaneously closed, the second end of the second control switch outputs starting voltage to the transmitter;
the feedback circuit is configured to output a control signal to the controller in response to the feedback voltage to control the inverter to start or shut down;
the protection circuit is electrically connected to the switching circuit, and is configured to filter noise energy of the starting voltage and store electric energy when the starting voltage is output by the switching circuit, and provide a freewheel loop for the transmitter when the starting voltage is stopped from being output by the switching circuit;
when the feedback circuit receives the feedback voltage, the control signal is at a low level; when the feedback circuit does not receive the feedback voltage, the control signal is high level.
2. The control circuit of claim 1, wherein the current protector comprises a fuse or a protection resistor.
3. The control circuit of claim 1 wherein the feedback circuit comprises a second voltage source, a triode, a feedback resistor, a divider resistor, a pull-up resistor, a matched resistor, and a filter capacitor, wherein,
the first end of the feedback resistor is connected to the first connecting point, and the second end of the feedback resistor is respectively connected with the base electrode of the triode and the first end of the voltage dividing resistor;
the collector of the triode is respectively connected to the first end of the pull-up resistor and the first end of the matching resistor, and the emitter of the triode is grounded;
the electric energy output end of the second voltage source is connected to the second end of the pull-up resistor, the second end of the matching resistor is connected to the first end of the filter capacitor to form a second connection point, and the second connection point is used for outputting the control signal;
and the second end of the filter capacitor and the second end of the divider resistor are both connected to the emitter of the triode.
4. The control circuit of claim 3, wherein the protection circuit comprises a first diode and a storage capacitor, wherein,
the cathode of the first diode is connected to the second end of the second control switch, and the anode of the first diode is grounded;
the energy storage capacitor is connected in parallel with two ends of the first diode and is used for outputting the starting voltage to the transmitter.
5. A photovoltaic energy storage inverter system, comprising: photovoltaic module, receiver, transmitter, energy storage inverter, relay, controller, load, grid and a control circuit according to any of claims 1-4, wherein,
the control circuit responds to the control switch state to respectively output a starting voltage and a control signal to the transmitter and the controller;
the controller responds to the level of the control signal to control the relay, and when the control signal is at a low level, the relay is controlled to be closed; when the control signal is at a high level, the relay is controlled to be disconnected;
the relay is arranged between the energy storage inverter and the load;
the transmitter outputting a sustain-on signal to the receiver in response to the start-up voltage;
the receiver is arranged between the photovoltaic module and the energy storage inverter, responds to the maintenance on signal to maintain the conduction between the photovoltaic module and the energy storage inverter, and if the receiver does not receive the maintenance on signal, the connection between the photovoltaic module and the energy storage inverter is disconnected;
the power grid is connected to the load, the power grid being configured to power the load when the relay is open.
6. A parallel control circuit for a parallel energy storage inverter system comprising n+1 controllers and n+1 energy storage inverters, the circuit comprising: a switching circuit and n+1 feedback circuits, wherein,
the switching circuits are respectively connected to the n+1 feedback circuits, and the switching circuits are configured to respectively output feedback voltages to the corresponding feedback circuits in response to the switching states;
the switching circuit comprises a first voltage source, a second diode, a fuse and N+1 control switches, wherein the electric energy output end of the first voltage source is connected to the anode of the second diode, the cathode of the second diode is connected to the first end of the fuse, and the second end of the fuse is connected to the first end of the first control switch; the N+1 control switches are sequentially connected end to form corresponding N connection points, the second end of the first control switch is connected to the first end of the second control switch to form a first connection point, and the second end of the N control switch is connected to the first end of the N+1 control switch to form an N connection point; when the continuous M control switches including the first control switch are all closed, the first connecting point to the Mth connecting point respectively output corresponding starting voltages;
the feedback circuit is configured to output a control signal to a respective controller in response to the feedback voltage to control the respective energy storage inverter to start or shut down;
when the feedback circuit receives the feedback voltage, the control signal is at a low level; when the feedback circuit does not receive the feedback voltage, the control signal is high level.
7. The parallel control circuit of claim 6, wherein the feedback circuit comprises a second voltage source, a triode, a feedback resistor, a divider resistor, a pull-up resistor, a matched resistor, and a filter capacitor, wherein,
the first end of the feedback resistor is connected to the second end of the corresponding control switch, and the second end of the feedback resistor is respectively connected with the base electrode of the triode and the first end of the voltage dividing resistor;
the collector of the triode is respectively connected to the first end of the pull-up resistor and the first end of the matching resistor, and the emitter of the triode is grounded;
the electric energy output end of the second voltage source is connected to the second end of the pull-up resistor, the second end of the matching resistor is connected to the first end of the filter capacitor to form a signal output point, and the signal output point is used for outputting the control signal;
and the second end of the filter capacitor and the second end of the divider resistor are both connected to the emitter of the triode.
8. A parallel energy storage inverter system comprising n+1 controllers, n+1 energy storage inverters, n+1 relays, a load, a power grid, and a parallel control circuit according to any one of claims 6-7, wherein,
the electric energy output end of the power grid is connected to the load;
the parallel control circuit responds to the control switch state and respectively outputs corresponding control signals to corresponding controllers;
the controller responds to the level of the control signal to control the corresponding energy storage inverter, and when the control signal is at a low level, the controller controls the energy storage inverter to start; when the control signal is at a high level, the energy storage inverter is controlled to be closed;
the output ends of the N+1 energy storage inverters are connected to one end of the corresponding relay;
the other ends of the N+1 relays are electrically connected to the load, and when any relay is closed and the corresponding energy storage inverter is in a starting state, the energy storage inverter supplies power to the load.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310049047.6A CN116014798B (en) | 2023-02-01 | 2023-02-01 | Control circuit, parallel control circuit and energy storage inverter system thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310049047.6A CN116014798B (en) | 2023-02-01 | 2023-02-01 | Control circuit, parallel control circuit and energy storage inverter system thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN116014798A CN116014798A (en) | 2023-04-25 |
| CN116014798B true CN116014798B (en) | 2023-06-20 |
Family
ID=86030071
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310049047.6A Active CN116014798B (en) | 2023-02-01 | 2023-02-01 | Control circuit, parallel control circuit and energy storage inverter system thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116014798B (en) |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5852454B2 (en) * | 2012-01-30 | 2016-02-03 | Ｊｘ日鉱日石エネルギー株式会社 | Solar cell module and solar power generation system |
| CN204031043U (en) * | 2014-08-28 | 2014-12-17 | 常州天合光能有限公司 | There is the photovoltaic system of intelligent turn-off function |
| CN106981881A (en) * | 2016-01-18 | 2017-07-25 | 台达电子企业管理（上海）有限公司 | A kind of photovoltaic generating system and its rapidly switch off method |
| CN210609056U (en) * | 2019-10-21 | 2020-05-22 | 阳光电源股份有限公司 | Photovoltaic inverter |
| US11532935B2 (en) * | 2020-03-09 | 2022-12-20 | Delta Electronics (Shanghai) Co., Ltd | Rapid shutdown device for photovoltaic system and control method thereof and protection system |
| CN115528649A (en) * | 2022-09-28 | 2022-12-27 | 华为数字能源技术有限公司 | Photovoltaic system and circuit protection method of photovoltaic system |
-
2023
- 2023-02-01 CN CN202310049047.6A patent/CN116014798B/en active Active
Non-Patent Citations (1)
| Title |
|---|
| 基于灰色预测的自动化太阳能光伏并网发电系统设计;孙安 等;流体测量与控制;第3卷(第6期);第87-91页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN116014798A (en) | 2023-04-25 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| WO2012031428A1 (en) | Photovoltaic module capable of being electrically isolated and electrical isolation method thereof | |
| CN110224381B (en) | Photovoltaic inverter and photovoltaic power generation system thereof | |
| CN114050811B (en) | Multi-input shutoff device, control method and photovoltaic power generation system | |
| WO2017101647A1 (en) | Power-on/power-off drive circuit and control method therefor | |
| CN105656065A (en) | Energy storage control system and method thereof | |
| CN116014798B (en) | Control circuit, parallel control circuit and energy storage inverter system thereof | |
| CN112886640A (en) | Current limiting circuit and energy storage system | |
| WO2006136100A1 (en) | Power supplying device and power supplying method | |
| CN112072741A (en) | One-key starting system and method for household energy storage system | |
| CN110061559B (en) | Off-line uninterrupted power supply and control method thereof | |
| CN108092395A (en) | A kind of backup battery incision and floating charge control device | |
| CN113972817A (en) | Solid-state transformer fault handling system | |
| JP6671979B2 (en) | Power supply switching device | |
| CN104701936A (en) | Uninterruptible power supply (UPS) second disconnection circuit and second disconnection method | |
| CN112003364B (en) | Standby power module and server power supply | |
| CN116780780B (en) | Power supply control device | |
| CN215378508U (en) | Control circuit of battery management system, battery management system and electronic equipment | |
| CN219740000U (en) | DC-DC input circuit of electric control system | |
| CN218940750U (en) | Off-line uninterrupted power supply | |
| CN214956636U (en) | Switch circuit for DC heavy current occasion and battery charging and discharging control circuit | |
| CN214506569U (en) | Current limiting circuit and energy storage system | |
| CN220754419U (en) | Static change-over switch and power supply conversion circuit | |
| CN216981854U (en) | Photovoltaic power generation system | |
| CN220139516U (en) | Photovoltaic panel turn-off control device | |
| CN116054422B (en) | Energy storage device and energy storage system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |