A hybrid energy power supply system

Abstract

The present invention discloses a hybrid energy power supply system. The hybrid energy power supply system includes a solar photovoltaic cell array, an AC power supply, a control circuit, and at least one group of power input switching devices; any of the power input switching devices includes a double-pole double-throw relay and a dual-mode converter; the control circuit is connected to the coil of the double-pole double-throw relay, the first selection contact end of the double-pole double-throw relay is connected to the AC power supply, the second selection contact end of the double-pole double-throw relay is connected to the solar photovoltaic cell array, the common contact of the double-pole double-throw relay is connected to the input end of the dual-mode converter, and the output end of the dual-mode converter is connected to the power supply end of the power load. The present invention can dynamically switch the solar photovoltaic cell array and the AC power supply through a group of dual-mode converters, thereby reducing idle equipment and improving equipment utilization.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy power supply systems, and in particular to a hybrid energy power supply system. Background Art

[0002] As people's demand for energy increases significantly, solar photovoltaic cell array power supply has been widely used as a green new energy power supply method. However, due to unstable factors such as uneven spatial distribution of light intensity and changes over time, the solar power supply system cannot ensure that the load works continuously and stably.

[0003] In order to achieve continuous and stable power supply in power-consuming places such as communication systems and ensure that the load can work normally, it is usually selected Figure 1 The traditional hybrid energy power supply system shown in the figure makes full use of solar energy when there is sunshine, and uses mains electricity or fuel generators for power supply at night or on cloudy days. Since there are two different power sources in the traditional hybrid energy power supply system, namely the solar photovoltaic cell array and the AC power supply, two sets of converters are required to convert the DC power of the solar photovoltaic cell array and the AC power supply into stable DC power with the same nominal voltage through a DC converter and a rectifier, so as to output it to the load and charge the battery at the same time. However, through research and experiments, it is found that the normal operation of this traditional hybrid energy power supply system requires that both sets of converters have sufficient output power, so that when one set of power supply cannot supply power, the other set of power supply can still guarantee power supply. However, in fact, the total power of the converter must be more than twice the load power, and in most cases, one set of converters is always idle. Summary of the invention

[0004] In order to overcome the defects of the prior art, the present invention provides a hybrid energy power supply system, which can dynamically switch the solar photovoltaic cell array and the AC power supply through a set of dual-mode converters, thereby reducing idle equipment and improving equipment utilization.

[0005] In order to solve the above technical problems, in a first aspect, an embodiment of the present invention provides a hybrid energy power supply system, including a solar photovoltaic cell array, an AC power supply, a control circuit, and at least one set of power input switching devices;

[0006] Any of the power input switching devices includes a double-pole double-throw relay and a dual-mode converter;

[0007] The control circuit is connected to the coil of the double-pole double-throw relay, the first selection contact end of the double-pole double-throw relay is connected to the AC power supply, the second selection contact end of the double-pole double-throw relay is connected to the solar photovoltaic cell array, the common contact of the double-pole double-throw relay is connected to the input end of the dual-mode converter, and the output end of the dual-mode converter is connected to the power supply end of the power load.

[0008] Furthermore, the hybrid energy power supply system also includes a battery, and the battery is connected to the output end of the dual-mode converter.

[0009] Furthermore, the double-pole double-throw relay includes a self-resetting relay.

[0010] Furthermore, the double-pole double-throw relay includes a magnetic latching relay.

[0011] Furthermore, the first selection contact terminal of the double-pole double-throw relay is a normally closed contact terminal, and the second selection contact terminal of the double-pole double-throw relay is a normally open contact terminal.

[0012] Furthermore, when the hybrid energy power supply system includes a set of the power input switching devices, the control circuit is configured as follows:

[0013] Real-time detection of the output voltage of the solar photovoltaic cell array;

[0014] When the output voltage is greater than or equal to a first preset voltage, controlling the selection switch of the double-pole double-throw relay to be connected to the second selection contact end;

[0015] When the output voltage is less than or equal to a second preset voltage, the selection switch of the double-pole double-throw relay is controlled to be connected to the first selection contact end; wherein the second preset voltage is less than the first preset voltage.

[0016] Furthermore, when the hybrid energy power supply system includes at least two groups of power input switching devices, the control circuit is configured as follows:

[0017] Real-time detection of the output voltage of the solar photovoltaic cell array;

[0018] When the output voltage is greater than or equal to a first preset voltage, controlling a selection switch of a double-pole double-throw relay of one group of the power input switching devices to be connected to the second selection contact terminal;

[0019] After controlling a double-pole double-throw relay of one group of the power input switching devices to be connected to the solar photovoltaic cell array, regularly detecting the output current of the dual-mode converter of the group of the power input switching devices;

[0020] When the output current is greater than or equal to the first preset current, the selection switches of the double-pole double-throw relays of the next group of the power input switching devices are controlled one by one to be connected to the second selection contact end until the average load rate of all corresponding dual-mode converters is no more than the first preset load rate.

[0021] Furthermore, the control circuit is configured as follows:

[0022] When the output current is less than or equal to a second preset current, the selection switch of the double-pole double-throw relay of the group of power input switching devices is controlled to be connected to the first selection contact end; wherein the second preset current is less than the first preset current.

[0023] Furthermore, the first preset voltage is less than or equal to a starting voltage of the dual-mode converter, and the second preset voltage is equal to a difference between the starting voltage of the dual-mode converter and a preset voltage difference.

[0024] Furthermore, the first preset voltage is less than or equal to a starting voltage of the corresponding dual-mode converter, and the first preset current is equal to 90% of a rated current of the corresponding dual-mode converter.

[0025] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0026] An embodiment of the present invention provides a hybrid energy power supply system including a solar photovoltaic cell array, an AC power supply, a control circuit and at least one group of power input switching devices, wherein the control circuit is connected to a coil of a double-pole double-throw relay, a first selection contact end of the double-pole double-throw relay is connected to the AC power supply, a second selection contact end of the double-pole double-throw relay is connected to the solar photovoltaic cell array, a common contact of the double-pole double-throw relay is connected to an input end of a dual-mode converter, and an output end of the dual-mode converter is connected to a power supply end of an electrical load, so that the control circuit controls the double-pole double-throw relay under the action of a higher output voltage of the solar photovoltaic cell array. The selection switch of the device is connected to its second selection contact terminal, so that the corresponding dual-mode converter can be switched to the solar photovoltaic cell array side to work, and the direct current of the solar photovoltaic cell array is converted into stable direct current. Under the action of the lower output voltage of the solar photovoltaic cell array, the control circuit controls the selection switch of the double-pole double-throw relay to be connected to its first selection contact terminal, so that the corresponding dual-mode converter can be switched back to the AC power supply side to work, and the AC power of the AC power supply is converted into stable direct current, thereby converting the DC power of the solar photovoltaic cell array and the AC power of the AC power supply into stable direct current with the same nominal voltage and outputting them to the power load. The embodiment of the present invention can dynamically switch the solar photovoltaic cell array and the AC power supply through a group of dual-mode converters, thereby reducing idle equipment and improving equipment utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of a traditional hybrid energy power supply system in the prior art;

[0028] Figure 2 is a structural schematic diagram of a hybrid energy power supply system in an embodiment of the present invention;

[0029] Figure 3 A schematic diagram of a structure in which a double-pole double-throw relay is connected to a control circuit in an embodiment of the present invention;

[0030] Figure 4 Schematic diagram of a control circuit in an embodiment of the present invention.

[0031] The reference numerals in the accompanying drawings of the specification are as follows:

[0032] 1: AC power supply; 2: Solar photovoltaic cell array; 3: Double-pole double-throw relay; 4: Dual-mode converter; 5: Power load; 6: Battery; 7: Control circuit. DETAILED DESCRIPTION

[0033] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] See also Figure 2-4 .

[0035] like Figure 2-3 As shown, an embodiment of the present invention provides a hybrid energy power supply system, including a solar photovoltaic cell array 2, an AC power supply 1, a control circuit 7, and at least one group of power input switching devices; any power input switching device includes a double-pole double-throw relay 3 and a dual-mode converter 4; the control circuit 7 is connected to the coil of the double-pole double-throw relay 3, the first selection contact end of the double-pole double-throw relay 3 is connected to the AC power supply 1, the second selection contact end of the double-pole double-throw relay 3 is connected to the solar photovoltaic cell array 2, the common contact of the double-pole double-throw relay 3 is connected to the input end of the dual-mode converter 4, and the output end of the dual-mode converter 4 is connected to the power supply end of the power load 5.

[0036] It should be noted that the operating voltage range of the solar photovoltaic cell array 2 is substantially overlapped with the operating voltage range of the AC power supply 1. The AC power supply 1 includes a mains power supply. The control circuit 7 includes, but is not limited to, a digital circuit or an analog circuit or a circuit containing a microcontroller unit (MCU). The dual-mode converter 4 is compatible with AC and DC inputs, and can operate safely under an AC 220Vac grid voltage to convert the input AC power into a stable DC output, and can also operate safely under a photovoltaic power supply of up to 400Vdc to convert the input DC power with large fluctuations into a stable DC output, and the output voltage is the same in both modes.

[0037] As an example, when the hybrid energy power supply system includes a group of power input switching devices, that is, the power input switching device includes a double-pole double-throw relay 3 and a dual-mode converter 4, the control circuit 7 is connected to the coil of the double-pole double-throw relay 3, the first selection contact end of the double-pole double-throw relay 3 is connected to the AC power supply 1, the second selection contact end of the double-pole double-throw relay 3 is connected to the solar photovoltaic cell array 2, the common contact of the double-pole double-throw relay 3 is connected to the input end of the dual-mode converter 4, and the output end of the dual-mode converter 4 is connected to the power supply end of the power load 5.

[0038] Among them, the control circuit 7 uses the DC input on one side of the solar photovoltaic cell array 2 as a control signal to control the double-pole double-throw relay 3. When the sunlight is enhanced, the output voltage of the solar photovoltaic cell array 2 increases. Under the action of the higher output voltage of the solar photovoltaic cell array 2, the control circuit 7 controls the selection switch of the double-pole double-throw relay 3 to be connected to its second selection contact end, so that the dual-mode converter 4 can switch to the solar photovoltaic cell array 2 side to work, and convert the DC power of the solar photovoltaic cell array 2 into stable DC power; when the sunlight is weakened, the output voltage of the solar photovoltaic cell array 2 decreases. Under the action of the lower output voltage of the solar photovoltaic cell array 2, the control circuit 7 controls the selection switch of the double-pole double-throw relay 3 to be connected to its first selection contact end, so that the dual-mode converter 4 can switch back to the AC power supply 1 side to work, and convert the AC power of the AC power supply 1 into stable DC power, thereby converting the DC power of the solar photovoltaic cell array 2 and the AC power of the AC power supply 1 into stable DC power with the same nominal voltage and outputting it to the power load 5.

[0039] As an example, when the hybrid energy power supply system includes three groups of power input switching devices, that is, the first group of power input switching devices includes a first double-pole double-throw relay 3 and a first dual-mode converter 4, the second group of power input switching devices includes a second double-pole double-throw relay 3 and a second dual-mode converter 4, and the third group of power input switching devices includes a third double-pole double-throw relay 3 and a third dual-mode converter 4, the control circuit 7 is respectively connected to the wire packages of the first double-pole double-throw relay 3, the second double-pole double-throw relay 3, and the third double-pole double-throw relay 3, and the first double-pole double-throw relay 3, the second double-pole double-throw relay 3, and the third double-pole double-throw relay 3. A selection contact end is connected to the AC power supply 1 respectively, the second selection contact ends of the first double-pole double-throw relay 3, the second double-pole double-throw relay 3, and the third double-pole double-throw relay 3 are respectively connected to the solar photovoltaic cell array 2, the common contact of the first double-pole double-throw relay 3 is connected to the input end of the first dual-mode converter 4, the common contact of the second double-pole double-throw relay 3 is connected to the input end of the second dual-mode converter 4, the common contact of the third double-pole double-throw relay 3 is connected to the input end of the third dual-mode converter 4, and the output ends of the first dual-mode converter 4, the second dual-mode converter 4, and the third dual-mode converter 4 are respectively connected to the power supply end of the power load 5.

[0040] Among them, the control circuit 7 uses the DC input on one side of the solar photovoltaic cell array 2 as a control signal to control the first double-pole double-throw relay 3, the second double-pole double-throw relay 3, and the third double-pole double-throw relay 3. When the sunlight is enhanced, the output voltage of the solar photovoltaic cell array 2 increases. Under the action of the higher output voltage of the solar photovoltaic cell array 2, the control circuit 7 controls the selection switch of any double-pole double-throw relay 3 among the first double-pole double-throw relay 3, the second double-pole double-throw relay 3, and the third double-pole double-throw relay 3 to be connected with its second selection contact end, so that the corresponding dual-mode converter 4 can be switched to the solar photovoltaic cell array 2 side to work, for example, the selection switches of the first double-pole double-throw relay 3 and the second double-pole double-throw relay 3 are controlled to be connected with their second selection contact ends, so that the first dual-mode converter 4 and the second dual-mode converter 4 can be switched to the solar photovoltaic cell array 2 side to work, and the DC power of the solar photovoltaic cell array 2 is converted into stable DC power; when the sunlight is reduced, ... When the voltage is weak, the output voltage of the solar photovoltaic cell array 2 is reduced. Under the action of the lower output voltage of the solar photovoltaic cell array 2, the control circuit 7 controls the selection switch of any double-pole double-throw relay 3 among all double-pole double-throw relays 3 connected to the solar photovoltaic cell array 2 to be connected to its first selection contact terminal, so that the corresponding dual-mode converter 4 can be switched back to the AC power supply 1 side to work. For example, the selection switch of the first double-pole double-throw relay 3 is controlled to be connected to its second selection contact terminal, so that the first dual-mode converter 4 can be switched back to the AC power supply 1 side to work, and the AC power of the AC power supply 1 is converted into stable DC power, thereby converting the DC power of the solar photovoltaic cell array 2 and the AC power of the AC power supply 1 into stable DC power with the same nominal voltage and outputting it to the power load 5.

[0041] This embodiment can dynamically switch the solar photovoltaic cell array 2 and the AC power supply 1 through a group of dual-mode converters 4, thereby reducing idle equipment and improving equipment utilization.

[0042] In a preferred embodiment, the hybrid energy power supply system further includes a battery 6 , which is connected to the output end of the dual-mode converter 4 .

[0043] This embodiment, by adding a battery 6 to the hybrid energy power supply system and connecting the battery 6 to the output end of the dual-mode converter 4, can convert the DC power of the solar photovoltaic cell array 2 and the AC power of the AC power source 1 into stable DC power with the same nominal voltage and output it to the battery 6.

[0044] In a preferred embodiment, the double-pole double-throw relay 3 comprises a self-resetting relay.

[0045] The self-resetting relay is in a normally closed state when the line package is not energized. This embodiment uses a self-resetting relay as a double-pole double-throw relay 3, which can enable the hybrid energy power supply system to start from the AC power supply 1 side in the default state, which is beneficial to reduce the chance of the relay directly breaking the DC current, reduce damage to the relay contacts, and extend the life of the relay.

[0046] In a preferred embodiment, the double-pole double-throw relay 3 comprises a magnetic latching relay.

[0047] The magnetic latching relay has the characteristics of power saving, stable performance, small size and large carrying capacity. This embodiment uses the magnetic latching relay as the double-pole double-throw relay 3, which can reduce the power consumption of the hybrid energy power supply system and improve the reliability of the hybrid energy power supply system.

[0048] In a preferred embodiment, the first selection contact terminal of the double-pole double-throw relay 3 is a normally closed contact terminal, and the second selection contact terminal of the double-pole double-throw relay 3 is a normally open contact terminal.

[0049] In this embodiment, the first selection contact terminal of the double-pole double-throw relay 3, that is, the normally closed contact terminal, is connected to the AC power supply 1, and the second selection contact terminal of the double-pole double-throw relay 3, that is, the normally open contact terminal, is connected to the solar photovoltaic cell array 2, so that the double-pole double-throw relay 3 is in a normally closed state when the line package is not powered on. This can enable the hybrid energy power supply system to start from the AC power supply 1 side in the default state, which is beneficial to reduce the chance of the relay directly breaking the DC current, reduce damage to the relay contacts, and extend the life of the relay.

[0050] like Figure 4 As shown, in a preferred embodiment, when the hybrid energy power supply system includes a group of power input switching devices, the control circuit 7 is configured to: detect the output voltage of the solar photovoltaic cell array 2 in real time; when the output voltage is greater than or equal to the first preset voltage, control the selection switch of the double-pole double-throw relay 3 to be connected to the second selection contact terminal; when the output voltage is less than or equal to the second preset voltage, control the selection switch of the double-pole double-throw relay 3 to be connected to the first selection contact terminal; wherein the second preset voltage is less than the first preset voltage.

[0051] In a preferred implementation of this embodiment, the first preset voltage is less than or equal to the starting voltage of the dual-mode converter 4, and the second preset voltage is equal to the difference between the starting voltage of the dual-mode converter 4 and the preset voltage difference.

[0052] The preset voltage difference includes a value of 10V.

[0053] It should be noted that the difference between the first preset voltage and the second preset voltage should be large to avoid frequent switching when sunlight fluctuates, and both the first preset voltage and the second preset voltage should be lower than the lower limit of the input voltage of the dual-mode converter 4 to avoid damage to the relay contacts caused by load switching, which is beneficial to extending the life of the relay.

[0054] As an example, when the hybrid energy power supply system includes a group of power input switching devices, the control circuit 7 detects the output voltage of the solar photovoltaic cell array 2 in real time. When the output voltage of the solar photovoltaic cell array 2 is greater than or equal to a first preset voltage, such as the starting voltage of the dual-mode converter 4, the control circuit 7 controls the selection switch of the double-pole double-throw relay 3 to be connected to its second selection contact end, so that the dual-mode converter 4 can be switched to the solar photovoltaic cell array 2 side to work, and convert the DC power of the solar photovoltaic cell array 2 into stable DC power; when the output voltage of the solar photovoltaic cell array 2 is less than or equal to the second preset voltage, that is, the starting voltage of the dual-mode converter 4 minus the voltage difference, such as the starting voltage of the dual-mode converter 4 minus 10V, the control circuit 7 controls the selection switch of the double-pole double-throw relay 3 to be connected to its first selection contact end, so that the dual-mode converter 4 can be switched back to the AC power supply 1 side to work, and convert the AC power of the AC power supply 1 into stable DC power, thereby converting the DC power of the solar photovoltaic cell array 2 and the AC power of the AC power supply 1 into stable DC power with the same nominal voltage and outputting it to the power load 5.

[0055] Among them, when the output voltage of the solar photovoltaic cell array 2 is less than or equal to the second preset voltage, that is, the starting voltage of the dual-mode converter 4 minus the voltage difference, for example, when the starting voltage of the dual-mode converter 4 is minus 10V, the control circuit 7 controls the selection switch of the double-pole double-throw relay 3 to be connected to its first selection contact terminal, so that the dual-mode converter 4 can be switched back to the AC power supply 1 side to work only after the output voltage of the solar photovoltaic cell array 2 is reduced to the point where the dual-mode converter 4 is completely shut down, thereby avoiding the dual-mode converter 4 from switching under load on the solar photovoltaic cell array 2 side, which is beneficial to reducing the requirements for the relay and extending the life of the relay.

[0056] In a preferred embodiment, when the hybrid energy power supply system includes at least two groups of power input switching devices, the control circuit 7 is configured to: detect the output voltage of the solar photovoltaic cell array 2 in real time; when the output voltage is greater than or equal to a first preset voltage, control the selection switch of the double-pole double-throw relay 3 of one group of power input switching devices to be connected to the second selection contact terminal; after controlling the double-pole double-throw relay 3 of one group of power input switching devices to be connected to the solar photovoltaic cell array 2, periodically detect the output current of the dual-mode converter 4 of the group of power input switching devices; when the output current is greater than or equal to the first preset current, control the selection switch of the double-pole double-throw relay 3 of the next group of power input switching devices to be connected to the second selection contact terminal one by one until the average load rate of all corresponding dual-mode converters 4 is not greater than the first preset load rate.

[0057] In a preferred implementation of this embodiment, the first preset voltage is less than or equal to the starting voltage of the corresponding dual-mode converter 4 , and the first preset current is equal to 90% of the rated current of the corresponding dual-mode converter 4 .

[0058] The first preset load rate includes a value of 90%.

[0059] As an example, when the hybrid energy power supply system includes three groups of power input switching devices, that is, the first group of power input switching devices includes a first double-pole double-throw relay 3 and a first dual-mode converter 4, the second group of power input switching devices includes a second double-pole double-throw relay 3 and a second dual-mode converter 4, and the third group of power input switching devices includes a third double-pole double-throw relay 3 and a third dual-mode converter 4, the control circuit 7 detects the output voltage of the solar photovoltaic cell array 2 in real time, and when the output voltage of the solar photovoltaic cell array 2 is greater than or equal to a first preset voltage, that is, the starting voltage of any one of the first dual-mode converter 4, the second dual-mode converter 4, and the third dual-mode converter 4, such as the first dual-mode converter 4, the control circuit 7 controls the selection switch of the first double-pole double-throw relay 3 to be connected to its second selection contact terminal, so that the first dual-mode converter 4 can switch to the working side of the solar photovoltaic cell array 2. The invention relates to a method for converting the direct current of the solar photovoltaic cell array 2 into stable direct current; after controlling the first double-pole double-throw relay 3 to be connected to the solar photovoltaic cell array 2, the output current of the first dual-mode converter 4 is detected regularly; when the output current of the first dual-mode converter 4 is greater than or equal to the first preset current, that is, 90% of the rated current of the first dual-mode converter 4, the double-pole double-throw relay 3 of the next group of power input switching devices is controlled, such as the selection switch of the second double-pole double-throw relay 3 is connected to its second selection contact end, so that the second dual-mode converter 4 can be switched to the solar photovoltaic cell array 2 side to work, and the direct current of the solar photovoltaic cell array 2 is converted into stable direct current; after controlling the second double-pole double-throw relay 3 to be connected to the solar photovoltaic cell array 2, the average load rate of the first dual-mode converter 4 and the second dual-mode converter 4 is calculated, and the output current of the second dual-mode converter 4 is detected regularly;When the average load rate of the first dual-mode converter 4 and the second dual-mode converter 4 is greater than the first preset load rate, i.e., 90%, and the output current of the second dual-mode converter 4 is greater than or equal to the first preset current, i.e., 90% of the rated current of the second dual-mode converter 4, the double-pole double-throw relay 3 of the next group of power input switching devices is controlled, for example, the selection switch of the third double-pole double-throw relay 3 is connected to its second selection contact end, so that the third dual-mode converter 4 can be switched to the solar photovoltaic cell array 2 side to work, and the direct current of the solar photovoltaic cell array 2 is converted into stable direct current, and if the first dual-mode converter 4 and the second dual-mode converter 4 is not greater than the first preset load rate, i.e., 90%, the double-pole double-throw relay 3 of the next group of power input switching devices is no longer controlled, so that when the output voltage of the solar photovoltaic cell array 2 rises to the starting voltage, the dual-mode converters 4 are switched one by one, so that only the dual-mode converters 4 that can meet the output power requirements of the solar photovoltaic cell array 2 are switched, and the remaining dual-mode converters 4 are still kept working on the AC power supply 1 side, so that the solar photovoltaic cell array 2 and the AC power supply 1 can work simultaneously, ensuring that when the sunlight is weak, the AC power supply 1 can be used to bear the power load 5 together instead of the battery 6 discharging. ;

[0060] In a preferred embodiment, the control circuit 7 is configured to: when the output current is less than or equal to a second preset current, control the selection switch of the double-pole double-throw relay 3 of the group of power input switching devices to be connected to the first selection contact terminal; wherein the second preset current is less than the first preset current.

[0061] As an example, after the control circuit 7 controls the first double-pole double-throw relay 3 to be connected to the solar photovoltaic cell array 2, if it is detected that the output current of the first dual-mode converter 4 is less than or equal to the second preset current, the control circuit 7 controls the selection switch of the first double-pole double-throw relay 3 to be connected to its first selection contact terminal, so that the first dual-mode converter 4 can be switched back to the AC power supply 1 side to work, and the AC power of the AC power supply 1 is converted into stable DC power; after the control circuit 7 controls the second double-pole double-throw relay 3 to be connected to the solar photovoltaic cell array 2, if it is detected that the output current of the second dual-mode converter 4 is less than or equal to the second preset current, the control circuit 7 controls the selection switch of the second double-pole double-throw relay 3 to be connected to its first selection contact terminal, so that the second dual-mode converter 4 can be switched back to the AC power supply 1 side. The power supply 1 works on one side to convert the AC power of the AC power supply 1 into stable DC power; after controlling the third double-pole double-throw relay 3 to be connected to the solar photovoltaic cell array 2, if it is detected that the output current of the third dual-mode converter 4 is less than or equal to the second preset current, the selection switch of the third double-pole double-throw relay 3 is controlled to be connected to its first selection contact end, so that the third dual-mode converter 4 can be switched back to the AC power supply 1 side to work, and the AC power of the AC power supply 1 is converted into stable DC power, so that when the output current of the solar photovoltaic cell array 2 decreases, some of the dual-mode converters 4 working on the solar photovoltaic cell array 2 side can be appropriately turned off, so that only the dual-mode converters 4 that can meet the output power requirements of the solar photovoltaic cell array 2 are retained. Among them, the turned-off dual-mode converter 4 can be switched back to the AC power supply 1 side to work for rectification.

[0062] In summary, the implementation of the embodiments of the present invention has the following beneficial effects:

[0063] An embodiment of the present invention provides a hybrid energy power supply system including a solar photovoltaic cell array 2, an AC power supply 1, a control circuit 7 and at least one group of power input switching devices, wherein the control circuit 7 is connected to the coil of a double-pole double-throw relay 3, the first selection contact end of the double-pole double-throw relay 3 is connected to the AC power supply 1, the second selection contact end of the double-pole double-throw relay 3 is connected to the solar photovoltaic cell array 2, the common contact of the double-pole double-throw relay 3 is connected to the input end of a dual-mode converter 4, and the output end of the dual-mode converter 4 is connected to the power supply end of an electrical load 5, so that the control circuit 7 controls the double-pole double-throw relay 3 under the action of a higher output voltage of the solar photovoltaic cell array 2. The selection switch of the electrical appliance 3 is connected to its second selection contact terminal, so that the corresponding dual-mode converter 4 can be switched to the solar photovoltaic cell array 2 side to work, and the direct current of the solar photovoltaic cell array 2 is converted into stable direct current. Under the action of the lower output voltage of the solar photovoltaic cell array 2, the control circuit 7 controls the selection switch of the double-pole double-throw relay 3 to be connected to its first selection contact terminal, so that the corresponding dual-mode converter 4 can be switched back to the AC power supply 1 side to work, and the AC power of the AC power supply 1 is converted into stable direct current, thereby converting the DC power of the solar photovoltaic cell array 2 and the AC power of the AC power supply 1 into stable direct current with the same nominal voltage and outputting it to the power load 5. The embodiment of the present invention can dynamically switch the solar photovoltaic cell array 2 and the AC power supply 1 through a group of dual-mode converters 4, thereby reducing idle equipment and improving equipment utilization.

[0064] The above is a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the principle of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A hybrid energy power supply system, characterized in that: It includes a solar photovoltaic cell array, an AC power supply, a control circuit, and at least one set of power input switching devices; Any of the power input switching devices includes a double-pole double-throw relay and a dual-mode converter; The control circuit is connected to the coil of the double-pole double-throw relay, the first selection contact end of the double-pole double-throw relay is connected to the AC power supply, the second selection contact end of the double-pole double-throw relay is connected to the solar photovoltaic cell array, the common contact of the double-pole double-throw relay is connected to the input end of the dual-mode converter, and the output end of the dual-mode converter is connected to the power supply end of the power load; When the hybrid energy power supply system includes a set of the power input switching devices, the control circuit is configured as follows: Real-time detection of the output voltage of the solar photovoltaic cell array; When the output voltage is greater than or equal to a first preset voltage, controlling the selection switch of the double-pole double-throw relay to be connected to the second selection contact end; When the output voltage is less than or equal to a second preset voltage, the selection switch of the double-pole double-throw relay is controlled to be connected to the first selection contact end; wherein the second preset voltage is less than the first preset voltage.

2. The hybrid energy power supply system according to claim 1, characterized in that: The hybrid energy power supply system also includes a battery, which is connected to the output end of the dual-mode converter.

3. The hybrid energy power supply system according to claim 1, characterized in that: The double-pole double-throw relay comprises a self-resetting relay.

4. The hybrid energy power supply system according to claim 1, characterized in that: The double-pole double-throw relay includes a magnetic latching relay.

5. The hybrid energy power supply system according to claim 1 or 3, characterized in that: The first selection contact terminal of the double-pole double-throw relay is a normally closed contact terminal, and the second selection contact terminal of the double-pole double-throw relay is a normally open contact terminal.

6. The hybrid energy power supply system according to claim 1, characterized in that: When the hybrid energy power supply system includes at least two groups of power input switching devices, the control circuit is configured as follows: Real-time detection of the output voltage of the solar photovoltaic cell array; When the output voltage is greater than or equal to a first preset voltage, controlling a selection switch of a double-pole double-throw relay of one group of the power input switching devices to be connected to the second selection contact terminal; After controlling a double-pole double-throw relay of one group of the power input switching devices to be connected to the solar photovoltaic cell array, regularly detecting the output current of the dual-mode converter of the group of the power input switching devices; When the output current is greater than or equal to the first preset current, the selection switches of the double-pole double-throw relays of the next group of the power input switching devices are controlled one by one to be connected to the second selection contact end until the average load rate of all corresponding dual-mode converters is no more than the first preset load rate.

7. The hybrid energy power supply system according to claim 6, characterized in that: The control circuit is configured to: When the output current is less than or equal to a second preset current, the selection switch of the double-pole double-throw relay of the group of power input switching devices is controlled to be connected to the first selection contact end; wherein the second preset current is less than the first preset current.

8. The hybrid energy power supply system according to claim 1, characterized in that: The first preset voltage is less than or equal to a starting voltage of the dual-mode converter, and the second preset voltage is equal to a difference between the starting voltage of the dual-mode converter and a preset voltage difference.

9. The hybrid energy power supply system according to claim 6 or 7, characterized in that: The first preset voltage is less than or equal to a starting voltage of the corresponding dual-mode converter, and the first preset current is equal to 90% of a rated current of the corresponding dual-mode converter.

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