RU183260U1 - Switching device for solar modules - Google Patents

Abstract

This utility model relates to electric power and can be used in the construction of power systems consisting of solar modules.

The technical result is to increase the reliability of the switching device of solar modules.

The switching device for solar modules includes a control unit and an executive unit, configured to connect up to four switched solar modules. The control unit is represented by a two-level comparator, each of the levels of which is connected to a pair of complementary bipolar transistors that control the current in the circuit of the executive unit through transistor switches on field-effect transistors. The inputs of the specified comparator are connected to the reference voltage element and the open circuit voltage sensor. The executive unit is represented by an electric circuit containing key-mode semiconductor devices that are installed with the ability to switch the switched solar modules in series, or series-parallel, or parallel connection. In a preferred embodiment, said semiconductor devices are represented by transistor switches. 7 c.p. f-ly, 3 Fig.

Description

Technical field

This utility model relates to electric power and can be used in the construction of power systems consisting of solar modules.

State of the art

Solar modules are designed to generate electricity using solar radiation. However, the dependence of such energy systems on the level of illumination imposes some restrictions on their practical application at different times of the day, time of year, and also in conditions of changing weather conditions. This means that the output voltage and current in the array of solar modules may not meet the power requirements for the load. A number of technical solutions are known from the prior art that make it possible to solve the problem of extracting maximum power from the operation of solar modules depending on the level of illumination by automatically switching the solar modules into a serial, parallel or series-parallel connection.

A technical solution is known according to the patent US4175249 (publ. 11/20/1979, IPC H02J 7/34), which discloses a switching device for solar modules, consisting of solar modules and allowing the switching of solar modules in various types of connections depending on ambient temperature and light level . The system comprises a module switching unit and a switching control unit, depending on the control signal of which in the module switching unit, the relays installed and connected in the electrical circuit in the connections between the working solar modules are closed and open. The control signal is generated depending on the voltage value on the control solar module located near the working modules. The comparator, which is part of the control unit, compares the voltage on the control module with a predetermined voltage, on the basis of which it generates a signal, which is then used to determine the required types of connections between the working solar modules.

A technical solution is known according to patent US6583522 (published on June 24, 2003, IPC H02J 1/00), in which a switching device for solar modules consisting of solar modules connected to a switching unit is disclosed. The latter consists of several SPDT relays installed in an electrical circuit between each of the modules. In the case when the relays are not energized, the solar modules are connected in series, otherwise the modules are connected in parallel. The voltage on the relay can be applied manually or automatically by means of a program on the module switching unit, depending on the time of day.

In well-known solutions, module switching circuits consisting of relays of various types are proposed. However, frequent switching of relays in conditions of a variable level of illumination can lead to their rapid wear, which reduces the reliability of the device as a whole.

Utility Model Disclosure

The objective of this utility model is to efficiently extract power from power systems consisting of solar modules, depending on the level of illumination.

The technical result is to increase the reliability of the switching device of solar modules.

The technical result is achieved due to the fact that in the switching device of the solar modules, including the control unit and the executive unit, configured to connect up to four switched solar modules, the control unit is represented by a two-level comparator, each level of which is connected to a pair of complementary bipolar transistors that control the current in the circuit of the executive unit through transistor switches on field-effect transistors, the inputs of the specified comparator are connected to the reference voltage element sensor open-circuit voltage, and the execution unit contains the circuitry comprising semiconductor devices operating in switching mode that are set to switch the switched solar modules in serial or parallel or series-parallel connection.

During the analysis of scientific, technical and patent information, the totality of essential features that were identical to those stated in this utility model was not revealed. Therefore, it can be assumed that the present utility model meets the patentability condition “Novelty”.

The implementation of this utility model is possible using well-known electrical elements and communication principles. Therefore, it can be assumed that the present utility model meets the patentability condition “Industrial Applicability”.

Brief Description of the Drawings

Figure 1 presents the electrical circuit of the control unit.

Figure 2 presents the electrical circuit of the Executive unit.

Figure 3 presents a block diagram for connecting multiple actuator units to a single control unit.

Utility Model Implementation

As an example of the implementation of the present utility model, consider the switching device of solar modules in accordance with figure 1 and figure 2.

As shown in figure 1, a two-level comparator with levels 12 and 13 is introduced into the control unit 10. The output of the first level 12 is connected to a pair of complementary bipolar transistors 14-2 and 14-4, while 14-2 is a PNP transistor (direct conductivity), 14-4 - NPN transistor (reverse conductivity). By analogy, the second level 13 is connected to the PNP transistor 14-1 and the NPN transistor 14-3.

Each bipolar transistor is connected in series with one of the field effect transistors 15-2, 15-4, 15-1, 15-3, operating in a key mode (transistor switches) and at the same time acting as amplifiers of current values. As a result, the transistors form electrical circuits I-IV, connecting the control unit 10 and the electrical circuit of the executive unit 20. The electric current through each of the circuits I-IV passes depending on the signals generated at the outputs of the comparator levels 12 and 13.

The inverse inputs of the comparator levels 12 and 13 can be connected to the open circuit voltage sensor U _OC 11 through controlled resistors. Direct inputs of the levels of the comparator 12 and 13 are connected to the element of the reference voltage U _OPOR 16.

Managed resistors allow you to vary the voltage value on the sensor to provide a more accurate response levels of the comparator 12 and 13 when comparing U _OC and U _SUPPORT . As the sensor 11, it is advisable to use a solar module located near the switched modules in order to take into account the current level of illumination.

As shown in figure 2, the Executive unit 20 is represented by an electrical circuit configured to connect up to four switched modules 21, 22, 23, 24. The numbering of these modules in practice can be arbitrary and in no way determines the design features of the device. In order to simplify hereinafter, ordinal numerals for the designation of switched modules are used in accordance with the direction of current flow in the circuit when the modules are connected in series.

The Executive unit 20 is represented by an electrical circuit containing key-mode semiconductor devices that are installed with the ability to switch the switched solar modules in series or series-parallel or parallel connection.

In a preferred embodiment of the present utility model, said semiconductor device is represented by a transistor switch. However, such a device can also be devices similar to the transistor, operating in the key mode, for example, thyristors (thyristor keys), triacs (triac keys), etc. Hereinafter, the implementation of the present utility model is considered only for the case in which the indicated semiconductor device is represented by a transistor switch.

In circuit I, current flows only if there is no signal at the output of the first level of comparator 12, while the transistor switch 25-1 in circuit I is installed in series between the second 22 and third 23 switched solar modules.

In circuit II, current flows only in the absence of a signal at the output of the second level of comparator 13, while transistor switches 26-1 and 26-2 in circuit II are installed in series between the first 21 and second 22 switched solar modules, between the third 23 and fourth 24 switched solar module.

In circuit III, current passes only if there is a low level signal at the output of the second level of comparator 13, while in circuit III two transistor switches 27-1 and 27-2 are installed in parallel, one of which is connected to the negative poles of the first 21 and third 23 switched solar modules, and the second with the positive poles of the second 22 and fourth 24.

In circuit IV, current flows only if there is a low level signal at the output of the first level of comparator 12, while in circuit IV transistor switches 28-1, 28-2, 28-3, 28-4, 28-5, 28-6, 28-7 are installed between the same poles of the solar modules 21, 22, 23 and 24.

All of these transistors can be connected to the electric circuit through resistors that perform the function of protecting against current surges in the circuit.

A device that performs the function of a load in an electric circuit is shown in FIG. 2 as a diode 30.

For the operation of the device, the power of field-effect transistors is selected based on the rated voltage U _{NOM of the} solar module, which allows the use of a real utility model with high-voltage solar modules.

Figure 3 presents a block diagram for connecting multiple actuating units 20 to one control unit 10. Such a connection is made through branched circuits I-IV.

In practice, the present utility model works as follows.

In the absence of sunlight, the voltage value U _OC at the sensor 11 is zero. At the same time, bipolar transistors 14-1 and 14-2 and field-effect transistors 15-1 and 15-2 connected in series with them, which pass the signal through circuits I, II to the electrical circuit of the actuator unit 20, are thus opened. Thus, in the actuator unit 20 transistors 25-1, 26-1 and 26-2 go into the open position ("open"), thereby including the working modules 21, 22, 23, 24 in a serial circuit (until the voltage U _OC = 7V).

This connection makes it possible to start the operation of solar modules for charging batteries, for example, with the actual voltage on each module U ₂₁ = U ₂₂ = U ₂₃ = U ₂₄ = 3.5V. Thus the total voltage ΣU _OUT = U ₂₁ + U _22, which leads to increased use of the illumination level borders and thus increase the efficiency of such compound solar + U ₂₃ + U ₂₄ = 14V, which is sufficient to charge the battery (batteries) modules.

With an increase in the level of illumination and the achievement of a voltage at the sensor 11 equal to 7V, the control unit 10 provides the switching of the solar modules in series-parallel connection. When the voltage at the input of the first level of the comparator 12 is _reached , equal to U _ОC = U _OPOR = 7V, a low level signal is generated at the output, as a result of which the transistor 14-1 switches to the closed position ("closes") and the transistor 14-3 opens. Accordingly, the transistor 25-1, switching the solar modules on the circuit I, is closed, and the transistors 27-1 and 27-2, the switching solar modules on the circuit III are opened. In this position, the solar modules 21 and 22, 23 and 24 are connected in series-parallel.

This connection increases power (output current increases).

With a further increase in voltage U _OC at the sensor 11 and the input of the second level of the comparator 13, transistor 14-2 closes, transistor 14-4 opens, and then transistors 26-1, 26-2 are closed along circuit II, all transistors from 28-1 open up to 28-7 in chain IV. Transistors 27-1 and 27-2 also remain open. In such switching, the solar modules 21, 22, 23, 24 are connected in parallel, which allows for the generation of maximum power.

Thus, the control unit 10 in accordance with the value of V _OC on the sensor 11 switches the solar modules so that each solar module operates at the maximum possible value of power.

Using this utility model is possible for switching fewer solar modules. When two modules are switched, for example, 21 and 22, the control unit will control the operation mode of transistors only in circuits II and IV.

Also, the use of this utility model is possible for switching a larger number of solar modules in case of connecting one control unit with several actuating units.

Claims (8)

1. A switching device for solar modules, including a control unit and an executive unit, configured to connect up to four switched solar modules, characterized in that the control unit is a two-level comparator, each of which levels is connected to a pair of complementary bipolar transistors that control the current in the executive circuit block through transistor switches on field-effect transistors, the inputs of the specified comparator are connected to the element of the reference voltage and the voltage sensor idle On the move, the actuator block is represented by an electrical circuit containing key-mode semiconductor devices that are installed with the ability to switch the switched solar modules into a serial, or series-parallel, or parallel connection. 2. The device according to claim 1, characterized in that the semiconductor devices operating in the key mode are represented by transistor switches. 3. The device according to claim 1, characterized in that the semiconductor devices operating in the key mode are represented by thyristor keys. 4. The device according to claim 2, characterized in that the bipolar transistors of the control unit form electrical circuits I-IV, connecting the control unit and the electrical circuit of the Executive unit, while the current through each of these circuits passes depending on the signals generated at the outputs of the levels comparator. 5. The device according to claim 4, characterized in that in circuit I, the current passes only if there is no signal at the output of the first level of the comparator, while the transistor switch in circuit I is installed in series between the second and third switched solar modules. 6. The device according to claim 4, characterized in that in circuit II, the current passes only in the absence of a signal at the output of the second level of the comparator, while the transistor switches in circuit II are installed in series between the first and second switched solar modules, between the third and fourth switched solar modules. 7. The device according to claim 4, characterized in that in circuit III, the current passes only if there is a low level signal at the output of the second level of the comparator, while in circuit III two transistor switches are installed in parallel, one of which is connected to the negative poles of the first and the third switched solar modules, and the second with the positive poles of the second and fourth switched solar modules. 8. The device according to claim 4, characterized in that in circuit IV, the current passes only if there is a low level signal at the output of the first level of the comparator, while in circuit IV transistor switches are installed between the same poles of the solar modules.

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