Uninterruptible power supply device
By using a power conversion module (PCS module) in the uninterrupted power supply system to connect it in parallel with the oil engine, the problems of high cost of UPS module and large battery capacity are solved, and lower operating costs and higher operating efficiency are achieved.
Patent Information
- Application Number
- CN202421820640.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-30
- Publication Date
- 2025-06-17
- Estimated Expiration
- 2034-07-30
AI Technical Summary
The UPS module has high cost and high battery capacity requirements, resulting in high operating costs for users.
Power conversion module (PCS module) is used instead of the traditional UPS module, and by changing the connection method with the oil engine, the PCS module and the oil engine are connected in parallel, reducing the dependence on the backup battery.
It reduces the operating cost of the entire power supply system, reduces the demand for large-capacity backup batteries, and improves the operating efficiency of the diesel generator through VSG control and working mode switching.
Smart Images
Figure CN222996285U_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to the technical field of uninterruptible power supply, and particularly to an uninterruptible power supply device. Background Art
[0002] In various power supply environments, there are many scenarios that require uninterruptible power supply, such as production lines, base stations, airports, computer rooms, etc. To meet the demand for uninterruptible power supply, a UPS system and a diesel generator are equipped in the entire power supply system to achieve uninterruptible power supply. Equipping a UPS module has a high cost, and to meet a certain backup time, a large-capacity backup battery needs to be equipped, resulting in a large amount of operating costs for users. Summary of the Utility Model
[0003] Embodiments of the present disclosure provide an uninterruptible power supply device to solve the problems of high cost of the UPS module and large demand for battery capacity.
[0004] Embodiments of the present disclosure provide an uninterruptible power supply device, including:
[0005] An energy storage module, a power conversion module, a first switch module, a second switch module, a first voltage detection module, a current detection module, and a control module;
[0006] The first end of the first switch module is used to connect to the commercial power, the first end of the second switch module is used to connect to the oil engine, the second end of the first switch module is connected to the second end of the second switch module, the second end of the first switch module is connected to the first end of the current detection module, the second end of the current detection module is used to connect to the load, the third end of the current detection module is connected to the control module, and the current detection module is used to detect the working current of the load;
[0007] The control ends of the first switch module and the second switch module are both connected to the control module;
[0008] The first end of the power conversion module is connected to the energy storage module, the second end of the power conversion module is connected to the second end of the second switch module, and the control end of the power conversion module is connected to the control module;
[0009] The first end of the first voltage detection module is connected to the first end of the first switch module, the second end of the first voltage detection module is connected to the control module, and the voltage detection module is used to detect the voltage of the commercial power.
[0010] In an exemplary embodiment of the present disclosure, an uninterruptible power supply device further includes:
[0011] A second voltage detection module;
[0012] The first end of the second voltage detection module is connected to the first end of the first switch module, and the second end of the second voltage detection module is connected to the control module. The second voltage detection module is used to detect the output voltage of the oil engine.
[0013] In an exemplary embodiment of the present disclosure, an uninterruptible power supply device further includes:
[0014] A timing module;
[0015] The timing module is connected to the control module.
[0016] In an exemplary embodiment of the present disclosure, an uninterruptible power supply device further includes:
[0017] A third switch module;
[0018] The first end of the third switch module is connected to the second end of the first switch module, the second end of the third switch module is connected to the first end of the current detection module, and the control end of the third switch module is connected to the control module.
[0019] In an exemplary embodiment of the present disclosure, an uninterruptible power supply device further includes:
[0020] The power conversion module includes two bidirectional DC / AC power conversion units;
[0021] The two bidirectional DC / AC power conversion units are connected in parallel.
[0022] In an exemplary embodiment of the present disclosure, an uninterruptible power supply device further includes:
[0023] A fourth switch module;
[0024] The first end of the fourth switch module is connected to the second end of the power conversion module, the second end of the fourth switch module is connected to the second end of the second switch module, and the control end of the fourth switch module is connected to the control module.
[0025] In an exemplary embodiment of the present disclosure, an uninterruptible power supply device further includes:
[0026] A fifth switch module;
[0027] The first end of the fifth switch module is used to connect to the commercial power, the second end of the fifth switch module is used to connect to the oil engine, the third end of the fifth switch module is used to connect to the load, and the control end of the fifth switch module is connected to the control module.
[0028] The beneficial effects of the uninterruptible power supply device provided by the embodiments of the present disclosure are:
[0029] First, the present disclosure uses a power conversion module (PCS module) to replace the UPS module in a traditional uninterruptible power supply system. Its connection method is changed from the original series connection of the UPS module and the diesel generator to a parallel connection of the PCS module and the diesel generator. By changing the connection method with the diesel generator, the present disclosure uses a PCS module with a lower cost to achieve uninterruptible power supply for the entire power system. Moreover, this solution does not require a large-capacity backup battery, and only the backup duration needs to meet the starting time of the diesel generator. Therefore, the operating cost of the entire power supply system is greatly reduced.
[0030] The PCS module is controlled using VSG control, and by switching the working modes of the PCS module, such as the off-grid mode, the strong-grid grid-connection mode, and the weak-grid grid-connection mode, it can provide inertia to the power grid while enabling the diesel generator to operate in the best operating state, reducing the operating cost and improving the operating efficiency.
[0031] Secondly, during the period when the mains power fails and the diesel generator starts, the PCS module switches to the off-line discharge state to supply power to the load, avoiding the situation of power failure of the load. After the diesel generator starts up, it switches to the grid-connected discharge state. At this time, the output of the converter is completely synchronized with the output of the diesel generator, avoiding the short-term power failure situation that occurs when the diesel generator switch is switched, and realizing seamless switching.
[0032] Finally, when switching to diesel generator power supply, if directly switched, it will have a large impact on the diesel generator, causing the output voltage of the diesel generator to be unstable, and there is a risk of damaging on-site equipment and the diesel generator. When the present disclosure switches to diesel generator power supply, it will change the working state of the PCS module to make it supply power jointly with the diesel generator in parallel, and the total output power is the load power. And the PCS module gradually reduces the grid-connected discharge power, and the diesel generator gradually increases the output power. Eventually, the diesel generator supplies power to the load alone. The present disclosure makes the diesel generator operate in the best operating state by changing the set power or working mode of the PCS module, reducing the operating cost. Description of the Drawings
[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art. Obviously, the following-described drawings are only some embodiments of the present disclosure. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.
[0034] Figure 1 It is a schematic structural diagram of an uninterruptible power supply device provided by an embodiment of the present disclosure;
[0035] Figure 2 It is a schematic diagram of the principle of an uninterruptible power supply device provided by an embodiment of the present disclosure;
[0036] Figure 3It is a schematic structural diagram of another uninterruptible power supply device provided by an embodiment of the present disclosure. Detailed implementation manners
[0037] In order to enable those skilled in the art to better understand this solution, the technical solutions in the embodiments of this solution will be clearly described below in conjunction with the accompanying drawings in the embodiments of this solution. Obviously, the described embodiments are part of the embodiments of this solution, rather than all of the embodiments. Based on the embodiments in this solution, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of this solution.
[0038] The term "including" in the specification, claims and above-mentioned accompanying drawings of this solution, as well as any other variations, means "including but not limited to", and is intended to cover non-exclusive inclusion, and is not limited only to the examples listed in the text. In addition, terms such as "first" and "second" are used to distinguish different objects, rather than to describe a specific order.
[0039] The implementation of the present disclosure will be described in detail below in conjunction with specific accompanying drawings:
[0040] Referring to Figure 1 and Figure 2 , an uninterruptible power supply device provided by the present disclosure includes:
[0041] In this embodiment, an energy storage module 10, a power conversion module 11, a first switch module 12, a second switch module 13, a first voltage detection module 14, a current detection module 15, and a control module 16;
[0042] The first end of the first switch module 12 is used to connect to the commercial power, the first end of the second switch module 13 is used to connect to the generator set, the second end of the first switch module 12 is connected to the second end of the second switch module 13, the second end of the first switch module 12 is connected to the first end of the current detection module 15, the second end of the current detection module 15 is used to connect to the load, the third end of the current detection module 15 is connected to the control module 16, and the current detection module 15 is used to detect the working current of the load;
[0043] The control ends of the first switch module 12 and the second switch module 13 are both connected to the control module 16;
[0044] The first end of the power conversion module 11 is connected to the energy storage module 10, the second end of the power conversion module 11 is connected to the second end of the second switch module 13, and the control end of the power conversion module 11 is connected to the control module 16;
[0045] The first end of the first voltage detection module 14 is connected to the first end of the first switch module 12, the second end of the first voltage detection module 14 is connected to the control module 16, and the voltage detection module is used to detect the voltage of the commercial power.
[0046] In this embodiment, the energy storage module 10 is used to store electrical energy and provide power support for the load when the mains power supply is interrupted or the generator has not fully started, ensuring the continuity of power supply. The power conversion module 11 can convert the electrical energy in the energy storage module 10 into a voltage and current form suitable for the load. It can adjust the output voltage and current according to the signal output by the control module 16 to meet the requirements of the load.
[0047] The first switch module 12 is used to control the on / off between the mains power and the uninterruptible power supply device. When the mains power is normal, the first switch module 12 is closed, and the mains power is directly supplied to the load; when the mains power is abnormal, the first switch module 12 is opened to prevent the mains power failure from affecting the load. The first switch module can be an SCR, which can be turned on under the action of an external control signal and under a forward voltage. Even after the control signal is removed, as long as the load current remains above a certain level, the SCR will continue to conduct until the current drops below the holding current.
[0048] The second switch module 13 is used to control the on / off between the generator and the uninterruptible power supply device. When the mains power fails or is unavailable, the second switch module 13 is closed, and the generator can directly supply power to the load.
[0049] The first voltage detection module 14 is used to detect the voltage of the mains power in real time and send the detected voltage value to the control module 16. The control module 16 determines whether the mains power is in a normal state according to the voltage value.
[0050] The current detection module 15 is used to detect the current passing through the load and send the detected current value to the control module 16. The control module 16 can adjust the output of the power conversion module 11 according to the current value or perform fault detection.
[0051] The control module 16 can receive signals from the voltage detection module and the current detection module 15, judge the states of the mains power, the generator, and the energy storage module 10 according to the preset logic, and control the working states of the first switch module 12, the second switch module 13, and the power conversion module 11 to achieve the purpose of uninterruptible power supply.
[0052] In this embodiment, the power conversion module 11 (PCS module) can be applied to grid-connected and off-grid systems, can realize the charge and discharge functions of the energy storage device in the system, and is also applicable to the grid-connected inverter in a weak grid environment when the generator is supplying power. When the grid frequency changes, it provides a certain inertia to the grid to maintain the stability of the system;
[0053] The PCS module is the hub connecting the energy storage module 10 and the generator in this disclosure. The PCS module can be an inverter, and there are the following working modes in actual operation:
[0054] First, off-grid discharge mode.
[0055] This operating mode is generally when there is a power failure in the mains and the oil engine (diesel generator) has not fully started. The energy storage module 10 supplies power to the load. At this time, the entire device can be regarded as an off-grid environment. In this mode, the energy storage module 10 is connected to the load through the PCS module. The load power is completely provided by the battery in the energy storage module 10. The PCS module generates the voltage amplitude and frequency through the power self-synchronization method. At this time, the PCS topology is a voltage-mode operation method, and the control is a voltage-source type VSG control. The output voltage waveform is approximately a sine wave, and the voltage amplitude, frequency, and phase can all be adjusted. The PCS module can be regarded as an adjustable AC voltage source.
[0056] When the load of this device changes, it causes the output frequency of the device to change. At this time, the VSG responds to the frequency change of the device, and suppresses the change rate and amplitude of the frequency by adaptively changing the moment of inertia and damping coefficient to follow the frequency change, automatically adjusts its output power to adapt to the load change, adapts to different load conditions faster, realizes better dynamic response, and maintains the system state stable. At this time, the frequency of the device deviates from the rated value of 50 Hz. By adjusting the given active power command of the PCS module to be equal to the active power output at this time, that is, the load power value, the output frequency of the device can be restored to the rated value of 50 Hz.
[0057] Second, grid-connected charge and discharge mode under strong grid.
[0058] This operating mode is generally when the mains is normal and the power grid supplies power to the load. At this time, the power grid can be regarded as a strong grid environment. In this mode, the energy storage module 10 is connected to the power grid and the load through the PCS module. Specifically, the charge and discharge state of the energy storage module 10 can be judged by judging the SOC state of the battery in the energy storage module 10. When the battery SOC is low, the power grid charges the energy storage module 10 through the PCS module; when the SOC is high, the energy storage module 10 discharges to the power grid through the PCS module, which can be charged and discharged to keep the battery SOC in the energy storage module 10 balanced and avoid the SOC being too high or too low.
[0059] At this time, the voltage is clamped by the power grid. The PCS module locks the phase of the power grid through a phase-locked loop, and the output voltage follows the power grid. The PCS topology is a current-mode operation method, and the output current waveform is approximately sinusoidal. The output power is adjusted by adjusting the current amplitude. The PCS module can be regarded as an adjustable AC current source, and the current-source type VSG control method is used. The input and output power are adjusted by adjusting the given active power command. When the output frequency of the device changes, the difference between the actual angular frequency and the rated angular frequency of the PCS passes through the active power control link of the virtual synchronous machine to form an active power difference, which is added to the rated active power to obtain the output active power at this time. Moreover, the moment of inertia and damping coefficient change adaptively with the power grid frequency, providing higher inertia support to the power grid and improving the system frequency response and stability. As the system frequency recovers to 50 Hz, the output power of the PCS gradually recovers to the given active power value.
[0060] Third, the grid-connected charge and discharge mode under weak grid conditions.
[0061] This working mode is generally when there is a power failure in the mains, and the diesel generator supplies power to the load. At this time, the diesel generator can be regarded as a weak grid environment. In this mode, the battery in the energy storage module 10 is connected to the diesel generator and the load through the PCS module. Specifically, the charge and discharge state of the energy storage can be judged by judging the SOC state of the battery in the energy storage module 10 and the operating state of the diesel generator. It can be charged and discharged, enabling the operating state of the diesel generator to be maintained in the best state and the energy storage SOC to be maintained in a balanced state.
[0062] The PCS module generates a voltage frequency through self-synchronization to track the voltage frequency of the diesel generator for synchronization. At this time, the PCS topology is a voltage-mode operation method, and the voltage-source type VSG control method is used. The input and output power can be adjusted by adjusting the given active power of the VSG, and the charge and discharge control of the battery in the energy storage module 10 can be carried out.
[0063] When the load of the device changes, it causes the output frequency of the device to change. The VSG moment of inertia and damping coefficient change adaptively, suppressing the rate of change of frequency and the amplitude of frequency change, and better dynamic response can be achieved and the stability of the system can be maintained. The virtual synchronous machine can change the output power of the PCS module by controlling the active power, providing inertia support to the power grid. As the power deficit of the device can be supplemented by the diesel generator, when the output frequency of the device recovers to 50 Hz, the output power of the PCS module gradually recovers to the rated value. At this time, the output power of the diesel generator can be changed by changing the given active power command value of the VSG, so that the diesel generator is maintained in the best operating state.
[0064] For example, when the output power of the diesel generator is lower than the power at the optimal operating state, the active command set value of the PCS module is adjusted to increase the absorbed power at this time; when the output power of the diesel generator is higher than the power at the optimal operating state, the active command set value of the PCS module is adjusted to reduce the absorbed power or discharge to the power grid at this time, so that the diesel generator operates at the optimal operating state. At the same time, the charge and discharge state of the PCS can also be changed to maintain the battery SOC of the energy storage module 10 within a balanced range and prevent overcharging or over-discharging of the energy storage module 10.
[0065] The working principle of the uninterruptible power supply device is as follows:
[0066] Normal mode: When there is no fault in the commercial power, it supplies power to the load through the first switch module 12; at this time, the diesel generator is in the shutdown state, and the output switch of the diesel generator (the second switch module 13) is in the off state;
[0067] The PCS module operates in the strong grid grid-connected mode, and the commercial power is rectified and step-down converted to charge the energy storage module 10; or the battery in the energy storage module 10 discharges to the power grid through step-up and inversion. By changing the set power command value of the PCS module to change the charge and discharge power, the SOC of the battery in the energy storage module 10 can be adjusted. In this mode, when the grid frequency fluctuates, the VSG control suppresses the frequency change through inertia self-adaptation and damping coefficient self-adaptation, provides inertia to the power grid, and enhances the stability of the device.
[0068] When the commercial power fails, the device switches from the commercial power supply mode to the diesel generator power supply mode:
[0069] When the uninterruptible power supply device is in the commercial power supply mode and the commercial power fails, the control module 16 controls the first switch module 12 to disconnect, and at the same time, the PCS module seamlessly switches from the strong grid grid-connected charging mode to the off-grid discharging mode to supply power to the load.
[0070] First, the PCS module generates voltage and frequency through self-synchronization to stabilize the load.
[0071] Then the control module 16 sends a start command to the diesel generator. After the diesel generator starts successfully, the PCS module tracks the voltage and frequency output by the diesel generator and performs pre-synchronization control. When the output of the PCS module is synchronized with the output of the diesel generator, the second switch module 13 closes, and at the same time, the PCS module seamlessly switches from the off-grid discharging mode to the weak grid grid-connected discharging mode, and the diesel generator and the PCS module jointly supply power to the load.
[0072] During this process, the PCS module gradually reduces the grid-connected discharging power, and the diesel generator gradually increases the output power. Finally, the diesel generator supplies power to the load alone, and the PCS module seamlessly switches from the weak grid grid-connected discharging mode to the weak grid grid-connected charging mode. The diesel generator can charge the energy storage module 10 through the PCS module.
[0073] If the generator is operating at its optimal operating state, the operating power of the PCS module does not need to be changed. If the output power of the generator exceeds the power at the optimal operating state, at this time, adjust the absorption power of the PCS module or change the operating state of the PCS module from the charging state to the discharging state to reduce the output power of the generator and make it operate at the optimal operating state. If the output power of the generator is lower than the power at the optimal operating state, at this time, adjust the active command given value of the PCS module to increase the absorption power of the energy storage module 10 and make the generator operate at the optimal operating state.
[0074] This can make the operating cost of the uninterruptible power supply device lower. In this mode, when the load fluctuates, it will cause a change in frequency. At this time, the PCS module responds to the frequency change and provides inertia to the power grid to maintain the stability of the device.
[0075] Generator power supply mode is converted to mains power supply mode:
[0076] The uninterruptible power supply device is in the generator power supply mode. When the control module 16 detects the restoration of the mains power, the operating mode of the PCS module is switched to the weak grid grid-connected discharging mode, and the PCS module and the generator jointly supply power to the load; the PCS module gradually increases the grid-connected discharging power, and the generator gradually reduces the output power. Finally, after the output power of the generator is 0, the control module 16 controls the second switch module 13 to disconnect. After the second switch module 13 disconnects, the generator is shut down.
[0077] At this time, the PCS module seamlessly switches from the weak grid grid-connected discharging mode to the off-grid discharging mode, and the PCS module independently supplies power to the load. Then the PCS module tracks the mains power and performs pre-synchronization control. When the output voltage and output frequency of the PCS module are synchronized with the mains power, the mains power supplies power to the load, and the PCS module seamlessly switches from the off-grid discharging mode to the strong grid grid-connected discharging mode, and the PCS module and the mains power jointly supply power to the load.
[0078] As the PCS module gradually reduces the grid-connected discharging power, the mains power gradually increases the output power, and finally the mains power alone supplies power to the load. At this time, the charging and discharging of the PCS module are determined by the SOC of the energy storage module 10. When the SOC of the energy storage module 10 is low, at this time, the mains power is rectified and stepped down to charge the battery; when the SOC of the energy storage is high, the energy storage is stepped up and inverted to discharge to the power grid; the charging and discharging power is set by the given power command of the PCS.
[0079] From the above, it can be concluded that the beneficial effects of this embodiment are:
[0080] First, the present disclosure uses a PCS module to replace the UPS module in the traditional uninterruptible power supply system. Its connection method is changed from the original series connection of the UPS module and the diesel generator to a parallel connection of the PCS module and the diesel generator. By changing the connection method with the diesel generator, the present disclosure uses a PCS module with a lower cost to achieve uninterrupted power supply for the entire power system. Moreover, this solution does not require a large-capacity backup battery, and only the backup duration needs to meet the starting time of the diesel generator. Therefore, the operating cost of the entire power supply system is greatly reduced.
[0081] The PCS module uses VSG control, and by switching the working mode of the PCS module, such as the off-grid mode, the strong-grid grid-connection mode, and the weak-grid grid-connection mode, it can provide inertia to the grid while enabling the diesel generator to operate in the best operating state, reducing the operating cost and improving the operating efficiency.
[0082] Secondly, during the period when the mains power fails and the diesel generator starts, the PCS module switches to the off-line discharge state to supply power to the load, avoiding the situation of power failure of the load. After the diesel generator starts up, it switches to the grid-connected discharge state. At this time, the output of the converter is completely synchronized with the output of the diesel generator, avoiding the short-term power failure situation that occurs when the diesel generator switch is switched, and realizing seamless switching.
[0083] Finally, when switching to diesel generator power supply, if directly switched, it will have a large impact on the diesel generator, causing the output voltage of the diesel generator to be unstable, and there is a risk of damaging the on-site equipment and the diesel generator. When the present disclosure switches to diesel generator power supply, it will change the working state of the PCS module to make it supply power jointly with the diesel generator in parallel, and the total output power is the load power. And the PCS module gradually reduces the grid-connected discharge power, and the diesel generator gradually increases the output power. Finally, the diesel generator supplies power to the load alone. The present disclosure enables the diesel generator to operate in the best operating state by changing the set power or working mode of the PCS module, reducing the operating cost.
[0084] In an embodiment of the present disclosure, referring to Figure 3 , an uninterruptible power supply device further includes:
[0085] A second voltage detection module 17;
[0086] The first end of the second voltage detection module 17 is connected to the first end of the first switch module 12, and the second end of the second voltage detection module 17 is connected to the control module 16. The second voltage detection module 17 is used to detect the output voltage of the diesel generator.
[0087] In this embodiment, the second voltage detection module 17 is mainly used to detect the output voltage of the diesel generator to ensure that when the diesel generator supplies power to the load, its voltage is stable within a safe and effective range.
[0088] The second voltage detection module 17 can detect the AC voltage output by the generator in real time to ensure that the output voltage meets the requirements of the load. When the control module 16 detects that the output voltage of the generator deviates from the preset normal range, it can control the energy storage module 10 to supply power to the load.
[0089] For example, when a power grid failure occurs, the control module 16 can control the second switch module 13 to turn on, and the generator supplies power to the load. However, when the generator has not fully started, the voltage of the generator collected by the second voltage detection module 17 cannot meet the requirements of the load. Therefore, the control module 16 can control the energy storage module 10 to supply power to the load through the PCS module to meet the power supply requirements of the load.
[0090] It can be concluded from the above that the second voltage detection module 17 can ensure that the voltage is stable within a safe range by detecting the output voltage of the generator in real time, avoiding potential damage to the load caused by voltage fluctuations, and ensuring the normal operation of the load. When the output voltage of the generator reaches the rated voltage of the load, the control module 16 can control the energy storage module 10 to gradually reduce the output power to reduce the operating cost of the device.
[0091] In an embodiment of the present disclosure, referring to Figure 3 a uninterruptible power supply device further includes:
[0092] a timing module 18;
[0093] The timing module 18 is connected to the control module 16.
[0094] In this embodiment, the PCS module is in the off-grid discharge mode to supply power to the load. It takes a certain amount of time for the generator to start from startup to full startup. When the output of the PCS module is synchronized with that of the generator, the second switch module 13 closes, and at this time, the PCS module and the generator jointly supply power to the load. To achieve more economical operation and reduce the operating cost, the PCS module needs to gradually reduce the grid-connected discharge power. At this time, the control module 16 can control the discharge time of the PCS module according to the time set by the timing module 18.
[0095] It can be concluded from the above that since the timing time of the timing module 18 can be set according to the power of the load or the output power of the generator, the control of the discharge time of the PCS module by the entire device is made more intelligent and convenient.
[0096] In an embodiment of the present disclosure, referring to Figure 3 a uninterruptible power supply device further includes:
[0097] a third switch module 19;
[0098] The first end of the third switch module 19 is connected to the second end of the first switch module 12, the second end of the third switch module 19 is connected to the first end of the current detection module 15, and the control end of the third switch module 19 is connected to the control module 16.
[0099] In this embodiment, the third switch module 19 is disposed between the second end of the first switch module 12 and the first end of the current detection module 15. Its main function is to control the on / off of the current under the instruction of the control module 16 to achieve circuit switching. For example, when an abnormal current or voltage is detected in the circuit, the control module 16 can control the third switch module 19 to disconnect to prevent damage to the current detection module 15 or the load, playing a role in circuit protection.
[0100] In an embodiment of the present disclosure, referring to Figure 3 , an uninterruptible power supply device further includes:
[0101] The power conversion module 11 includes two bidirectional DC / AC power conversion units 101;
[0102] The two bidirectional DC / AC power conversion units 101 are connected in parallel.
[0103] In this embodiment, the power conversion module 11 (PCS module) includes two bidirectional DC / AC power conversion units 101. When the energy storage module 10 discharges to the outside, it can supply power to the load through one of the bidirectional DC / AC power conversion units; when the energy storage module 10 receives charging operations from the power grid or the generator set, it can receive electrical energy through the other bidirectional DC / AC power conversion unit. Using different bidirectional DC / AC power conversion units 101 for such charging and discharging operations respectively can reduce the load of a single unit and extend the service life of the device.
[0104] The parallel connection between the two bidirectional DC / AC power conversion units 101 provides redundancy, that is, if one of the conversion units fails, the other unit can still continue to work, ensuring the uninterruptible power supply ability of the device and significantly improving the reliability and stability of the device.
[0105] In an embodiment of the present disclosure, referring to Figure 3 , an uninterruptible power supply device further includes:
[0106] The fourth switch module 20;
[0107] The first end of the fourth switch module 20 is connected to the second end of the power conversion module 11, the second end of the fourth switch module 20 is connected to the second end of the second switch module 13, and the control end of the fourth switch module 20 is connected to the control module 16.
[0108] In this embodiment, the fourth switch module 20 is connected between the second end of the power conversion module 11 and the second end of the second switch module 13. Its main function is to control the circuit connection or disconnection between the two according to the instructions of the control module 16. For example, when the power grid is normal, the fourth switch module 20 can isolate the power conversion module 11 from the second switch module 13, and when the power grid fails, it can quickly establish a connection between the two to ensure that the electric energy provided by the power conversion module 11 (PCS module) can be smoothly sent to the load. The control module 16 can make the PCS module work in different working modes by controlling the state of the fourth switch module 20.
[0109] In one embodiment of the present disclosure, referring to Figure 3 , an uninterruptible power supply device further includes:
[0110] A fifth switch module 21;
[0111] The first end of the fifth switch module 21 is used to connect to the commercial power, the second end of the fifth switch module 21 is used to connect to the generator set, the third end of the fifth switch module 21 is used to connect to the load, and the control end of the fifth switch module 21 is connected to the control module 16.
[0112] In this embodiment, the fifth switch module 21 can be an ATS transfer switch. In general, the ATS transfer switch in this embodiment is in an off state. Because the ATS transfer switch has a switching time of milliseconds during the switching process, and it will cause a large impact on the generator set when directly switching the ATS, so the power of the generator set is generally selected according to 1.2 - 1.5 times the load power.
[0113] When any one of the commercial power or the generator set power supply unit is working normally, the control module 16 in the present disclosure can realize the function of the ATS switch by controlling the working states of the first switch module 12 (such as SCR) and the second switch module 13, and change the PCS working mode before and after the switch is switched to achieve seamless switching between the generator set power supply and the commercial power supply, and the power of the generator set can be selected according to 1:1 of the load power.
[0114] It can be concluded from the above that the purpose of setting the ATS transfer switch in the present disclosure is to quickly switch between the commercial power and the generator set when both the first switch module 12 and the second switch module 13 fail to meet the power supply requirements of the load.
[0115] The above embodiments are only used to illustrate the technical solutions of the present disclosure, rather than to limit it; although the present disclosure has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present disclosure.
Claims
1. An uninterruptible power supply device, characterized in that: include: An energy storage module, a power conversion module, a first switch module, a second switch module, a first voltage detection module, a current detection module and a control module; The first end of the first switch module is used to connect to the mains, the first end of the second switch module is used to connect to the oil engine, the second end of the first switch module is connected to the second end of the second switch module, the second end of the first switch module is connected to the first end of the current detection module, the second end of the current detection module is used to connect to the load, the third end of the current detection module is connected to the control module, and the current detection module is used to detect the working current of the load; The control ends of the first switch module and the second switch module are both connected to the control module; The first end of the power conversion module is connected to the energy storage module, the second end of the power conversion module is connected to the second end of the second switch module, and the control end of the power conversion module is connected to the control module; The first end of the first voltage detection module is connected to the first end of the first switch module, the second end of the first voltage detection module is connected to the control module, and the voltage detection module is used to detect the voltage of the mains.
2. An uninterruptible power supply device as claimed in claim 1, characterized in that: Also includes: A second voltage detection module; The first end of the second voltage detection module is connected to the first end of the first switch module, the second end of the second voltage detection module is connected to the control module, and the second voltage detection module is used to detect the output voltage of the oil engine.
3. The uninterruptible power supply device according to claim 1, characterized in that: Also includes: Timing module; The timing module is connected to the control module.
4. The uninterruptible power supply device according to claim 1, characterized in that: Also includes: A third switch module; The first end of the third switch module is connected to the second end of the first switch module, the second end of the third switch module is connected to the first end of the current detection module, and the control end of the third switch module is connected to the control module.
5. The uninterruptible power supply device according to claim 1, characterized in that: The power conversion module includes two bidirectional DC / AC power conversion units; Two bidirectional DC / AC power conversion units are connected in parallel.
6. The uninterruptible power supply device according to claim 1, characterized in that: Also includes: a fourth switch module; The first end of the fourth switch module is connected to the second end of the power conversion module, the second end of the fourth switch module is connected to the second end of the second switch module, and the control end of the fourth switch module is connected to the control module.
7. The uninterruptible power supply device according to claim 1, characterized in that: Also includes: A fifth switch module; The first end of the fifth switch module is used to connect to the mains, the second end of the fifth switch module is used to connect to the oil engine, the third end of the fifth switch module is used to connect to the load, and the control end of the fifth switch module is connected to the control module.