Energy storage converter

Abstract

The invention relates to an energy storage converter. The energy storage converter comprises a control unit, an air cooling system and a system heating component. The air cooling system is used for cooling system heating components and comprises a fan, a fault feedback circuit connected with the control unit and a PWM signal generating circuit. The control unit judges that the energy storage converter is in a standby state, a starting state or a working state, when the energy storage converter is in the working state, the fault feedback circuit is stopped, when the energy storage converter is in the starting state, the PWM signal generating circuit and the fault feedback circuit are started, the PWM signal generating circuit provides a PWM signal for the fan to enable the fan to operate, and the fault feedback circuit is started; the fault feedback circuit detects whether the fan is stalled or not, if the fan is stalled, the fault feedback circuit outputs a fan fault signal, and the control unit is used for giving an alarm at least according to the fan fault signal. By adopting the method, fault detection of the energy storage converter on the fan can be realized, and the reliability of fault detection is improved.

Description

Technical Field

[0001] The present application relates to the technical field of power conversion, and in particular to an energy storage converter. Background Art

[0002] The energy storage inverter generates a lot of heat under load and needs a fan to dissipate the heat. The fan plays a key role in the normal operation and long life of the energy storage inverter. The energy storage inverter usually runs for a long time in a high temperature or high temperature and high humidity environment. The energy storage inverter dissipates heat through the rotation of the fan. If the fan is blocked or the fan stops due to a hardware failure, the temperature of the energy storage inverter will rise sharply, which will bring hidden dangers and risks. Therefore, it is very necessary to detect fan failures and blockages. The commonly used detection method is to detect fan failures by adding hardware circuits to the fan and observing the returned hardware signals, but the reliability is low. Summary of the invention

[0003] Based on this, it is necessary to provide an energy storage inverter to address the above technical problems, which can realize fault detection of the fan and improve the reliability of fault detection.

[0004] In a first aspect, the present application provides an energy storage inverter, which includes: a control unit, an air cooling system, and a system heating component, wherein the air cooling system is used to cool the system heating component, and includes: a fan, a fault feedback circuit connected to the control unit, and a PWM signal generating circuit, wherein the fault feedback circuit can send a fan fault signal to the control unit when a fault in the fan is detected; the control unit is used to determine whether the energy storage inverter is in one of a standby state, a start-up state, and a working state, and when the energy storage inverter is in the start-up state, the PWM signal generating circuit and the fault feedback circuit are enabled, and when the energy storage inverter is in the working state, the fault feedback circuit is disabled, and the start-up state is an intermediate state from the standby state to the working state; wherein, when the energy storage inverter is in the start-up state, the PWM signal generating circuit provides a PWM signal to the fan to make the fan run, and the control unit is used to at least issue an alarm based on the fan fault signal.

[0005] In one of the embodiments, the control unit is used to issue an alarm at least based on the fan fault signal, including the control unit being used to issue an alarm based on the duration of the fan fault signal and a first preset time, and issuing an alarm when the duration of the fan fault signal is greater than the first preset time.

[0006] In one of the embodiments, when the energy storage converter is in the startup state, the PWM signal is a constant PWM signal, and the constant PWM signal has a constant frequency and / or a constant duty cycle, so that the fan runs at a constant speed; wherein the constant speed of the fan is greater than the minimum fault detection speed, and the minimum fault detection speed is determined by the characteristics of the fan itself;

[0007] The constant speed of the fan is less than a preset speed to prevent condensation; wherein the preset speed is related to the ambient temperature, ambient humidity and internal temperature of the device, and the ratio of the constant speed of the fan to the rated speed of the fan is in the range of 25-50%.

[0008] In one embodiment, if the fan fault signal does not last for the first preset time, it is determined that the fault factor disappears and the fan fault signal is cleared; if the fan fault signal lasts for the first preset time, a fan fault alarm is issued, indicating that the fan has failed, but the fault time does not last to the second preset time. At this time, the maximum power of the energy storage inverter can be reduced to a set power without directly shutting down. The second preset time is much longer than the first preset time, for example, the second preset time is on the order of days, while the first preset time is on the order of seconds.

[0009] In one of the embodiments, the control unit is further configured to determine whether the fan alarm time exceeds a second preset time, and if so, control the energy storage converter to shut down and record the fan fault.

[0010] In one of the embodiments, when the energy storage inverter is in the standby state, the control unit enables the fault feedback circuit; wherein, the standby state includes a first standby stage and a second standby stage, in the first standby stage, the fan is in a running state, and the fault feedback circuit is used to detect whether the fan is blocked, and if the fan is blocked, the fault feedback circuit outputs a fan fault signal; in the second stage, the fan is in a stopped state, and the fault feedback circuit performs hardware fault detection on the fan, and if the fan has a hardware fault, the fault feedback circuit outputs a fan fault signal.

[0011] In one of the embodiments, the fault feedback circuit is used to send a fan fault signal. When there are multiple fans in the air cooling system, each fan is configured with a fault feedback circuit, and multiple fault feedback circuits are connected in parallel to obtain a fan fault signal.

[0012] In one of the embodiments, an overheating protection system is further included, and the overheating protection system includes an overheating feedback circuit connected to the control unit. When the energy storage inverter is in the working state, the control unit enables the overheating feedback circuit, and the overheating feedback circuit is used to send an overheating signal. The control unit can execute an overtemperature protection strategy based on the overheating signal.

[0013] In one of the embodiments, the over-temperature protection strategy includes a temperature derating curve, the temperature derating curve represents the negative correlation between the internal temperature of the energy storage converter and the operating rated power of the energy storage converter, and the control unit performs power control according to the temperature derating curve and the detected internal temperature;

[0014] Alternatively, the working state of the energy storage converter includes a full load mode and a low load mode, and the low load mode is enabled when the control unit receives the fan fault signal or the overheating signal.

[0015] In one of the embodiments, when the energy storage inverter is in standby mode, if the fan fault signal continues for a first preset time, the control unit issues a fan alarm and reduces the maximum power of the energy storage inverter to a set power, and the set power ranges from 60% to 80% of the rated power.

[0016] The above-mentioned energy storage converter, when the energy storage converter is in the startup state, the startup state is an intermediate state from the standby state to the working state, the control unit starts the PWM signal generating circuit and the fault feedback circuit, so as to provide a PWM signal to the fan through the PWM signal generating circuit to make the fan run, and detects whether the fan fails through the fault feedback circuit, when the fan is blocked, the fault feedback circuit sends a fault signal to the control unit, the control unit issues an alarm when receiving the fan fault signal, and disables the fault feedback circuit when the energy storage converter is in the working state. The present application improves the reliability of fan fault detection by different states of the energy storage converter, and the state of the fault feedback circuit is related to the state of the energy storage converter in real time, and avoids adverse consequences caused by misjudgment of fan faults, and avoids affecting the normal operation of the energy storage converter. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic diagram of the structure of an energy storage converter in one embodiment;

[0018] Figure 2 is a schematic diagram of a fault feedback circuit in an embodiment;

[0019] Figure 3 is a schematic diagram of a fault feedback circuit in another embodiment;

[0020] Figure 4It is a structural schematic diagram of an energy storage converter in another embodiment;

[0021] Figure 5 The figure is a schematic diagram of a flow chart of a fan failure detection by an energy storage converter in one embodiment. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0023] At present, the commonly used detection means is to detect fan faults by adding hardware detection circuits to the fan and observing the returned detection signals, but if the hardware detection circuit itself fails, the reliability of fan fault detection will be low. There are two signal feedbacks in the related art, one is to detect fan faults by observing the returned RD signal (Rat ion Detector, also known as rotor positioning signal). Under normal circumstances when the RD signal is returned, the fan may have a stall fault, so a fan stall fault self-recovery operation is required (the fan stops rotating due to stalling and triggers the fan fault, but the rotation is restored after a period of time, then the fan fault in this case will be cleared), and the fan will not always be in a running state. If the fan stops running actively, the fan stall fault that has been triggered may be mistakenly cleared. The other is to detect fan faults by observing the returned FG signal (Frequency Generator, also known as flywheel signal). Under normal circumstances when the FG signal is returned, the fan will not always be in a running state. If the fan stops running actively, the fan hardware fault and fan stall fault that have been triggered may be mistakenly cleared. In addition, since the RD signal is a signal used to detect the operating status of the fan, the hardware circuit will perform a logical inversion operation on the RD signal. The CPU receives the signal and makes a judgment. If it is a low level, the fan is running; if it is a high level, the fan is stopped. The FG signal is a square wave frequency signal used to reflect the speed of the fan motor, and a more complex circuit is required to generate and process the square wave frequency signal. Therefore, in terms of hardware cost, fans with FG signals are more complex in design and manufacturing, resulting in their prices generally being higher than fans that only return RD signals.

[0024] The energy storage inverter provided in the embodiment of the present application includes: a control unit, an air cooling system, and system heating components. Among them, the air cooling system is used to cool the system heating components. The air cooling system includes: a fan, a fault feedback circuit connected to the control unit, and a PWM signal generating circuit. The fault feedback circuit is used to send a fan fault signal to the control unit when a fan fault is detected. The control unit is used to determine whether the energy storage inverter is in one of the standby state, the startup state, and the working state, and when the energy storage inverter is in the startup state, the PWM signal generating circuit and the fault feedback circuit are enabled; when the energy storage inverter is in the working state, the fault feedback circuit is disabled. The startup state is an intermediate state from the standby state to the working state. When the energy storage inverter is in the startup state, the PWM signal generating circuit provides a PWM signal to the fan to make the fan run, and the control unit can issue an alarm when receiving a fan fault signal.

[0025] Furthermore, fan failures are divided into recoverable failures (such as stall failures, self-recovery failures of the hardware circuit) and irrecoverable failures (such as hardware damage). Therefore, a first preset time is set, and an alarm is issued only when the duration of the fan fault signal is greater than the first preset time; if it is less than the first preset time, it indicates that the fault has self-recovered, and no alarm is issued at this time, and the duration of the fan fault signal is reset. Among them, when the energy storage inverter is in the startup state, the fault feedback circuit is mainly used to detect whether the fan is stalled. If the fan is stalled, the feedback circuit outputs a fan fault signal. Of course, if other faults occur, this stage can also detect that the fault has occurred. In the startup stage of the energy storage inverter, the present application applies a PWM signal to the fan through a PWM signal generating circuit, and realizes fan fault detection through a fault feedback circuit, and does not affect the normal operation of the energy storage inverter, thereby improving the reliability of fan fault detection.

[0026] The energy storage converter according to the embodiment of the present application is described in detail below with reference to the accompanying drawings.

[0027] like Figure 1 As shown, a structural schematic diagram of an energy storage inverter 100 provided in an embodiment of the present application, the energy storage inverter 100 includes a system heating component 11, an air cooling system 12 and a control unit 13. Among them, the system heating component 11 can be a device of the energy storage inverter circuit, such as a power device of the circuit, and of course it can also be other heating components in the energy storage inverter. The air cooling system 12 is used to cool the system heating component 11 to maintain the energy storage inverter 100 at a suitable operating temperature. The air cooling system 12 includes a fan 122, a fault feedback circuit 121 and a PWM signal generating circuit 123, and the fan 122, the fault feedback circuit 121 and the PWM signal generating circuit 123 are all connected to the control unit 13.

[0028] It should be noted that the connection relationship and sequence shown in the figure are for convenience of explanation only. The connection sequence of each module or component should be determined by its function and internal logic, and does not constitute any limitation on the implementation process of the embodiment of the present application.

[0029] The control unit 13 is used to determine whether the energy storage inverter 100 is in one of the standby state, the startup state, and the working state. Among them, the startup state is the intermediate state of the energy storage inverter 100 from the standby state to the working state, and the working state is the state in which the energy storage inverter 100 performs charging and discharging work at 0 power light load state or a certain power after the energy storage inverter 100 is started. The startup time of the energy storage inverter 100 from the startup state to the working state generally takes more than ten seconds to several minutes. For example, for a small energy storage inverter 100, the startup time may be from tens of seconds to 1 minute. For a large energy storage inverter 100, the startup time is generally more than 3 minutes.

[0030] When the energy storage converter 100 is in the startup state, the control unit 13 enables the PWM signal generating circuit 123 and the fault feedback circuit 121, and the PWM signal generating circuit 123 provides a PWM signal to the fan 122, so that the fan 122 can operate. The fault feedback circuit 121 detects whether the fan 122 has a stall fault, and transmits a fan fault signal indicating whether the fan 122 is stalled to the control unit 13. This embodiment detects fan faults by observing the returned RD signal (Rat ion Detector, also known as the rotor positioning signal), and the cost is low. The RD signal can feedback whether the fan 122 is running or stopped. For example, when the fan 122 is running, the RD signal output is a low level, and when the fan 122 stops, the RD signal output is a high level. The fault feedback circuit 121 can be used to perform logical inversion to determine whether the fan 122 is faulty. Therefore, the stall fault can be determined by the RD signal.

[0031] like Figure 2As shown, it is a circuit diagram of the fault feedback circuit 121. The fault feedback circuit 121 sends a fan fault signal (FAN_ERR) to the control unit 13. If the fan 122 fails, the fan fault signal FANn_ERR corresponding to the fan 122 is equal to 1, the corresponding diode D is turned on, the base of the transistor Q2 is high, the transistor Q2 is turned on, and the fan fault signal FAN_ERR outputs a low level; if the fan 122 does not fail, the fan fault signal FANn_ERR corresponding to the fan 122 is equal to 0, the corresponding diode D is disconnected, the base of the transistor Q2 loses the driving signal, the transistor Q2 is disconnected, and the fan fault signal FAN_ERR outputs a high level. The control unit 13 may issue an alarm upon receiving a fan fault signal; further, in another embodiment, the alarm may be issued only after the duration of the fan fault signal exceeds a first preset time; further, the fan alarm time is counted, and when a second preset time is reached, it indicates that an irreversible fault has occurred in the fan. At this time, the fan 122 is controlled to shut down due to a fault, and the fan 122 fault is recorded to remind maintenance personnel to come to the site for repairs.

[0032] When the energy storage converter 100 is in operation, the control unit 13 disables the fault feedback circuit 121 , that is, does not perform fault detection, to prevent adverse effects caused by false alarms, thereby avoiding affecting the normal operation of the energy storage converter 100 .

[0033] According to the above description, the energy storage converter 100 of this embodiment starts the PWM signal generating circuit 123 and the fault feedback circuit 121 by the control unit 13 when the energy storage converter 100 is in the startup state, so as to provide a PWM signal to the fan 122 through the PWM signal generating circuit 123 to make the fan 122 run, and detects whether the fan 122 fails through the fault feedback circuit 121, and when the fan 122 fails, the fault feedback circuit 121 sends a fault signal to the control unit 13, and the control unit 13 issues an alarm when receiving the fan fault signal, so as to avoid the adverse consequences caused by the misjudgment of the fan 122 fault; and when the energy storage converter 100 is in the working state, no fault detection is performed, so as not to affect the normal operation of the energy storage converter. Furthermore, the state of the corresponding fault feedback circuit is different due to the different states of the energy storage converter, and the state of the fault feedback circuit is related to the state of the energy storage converter in real time, so as to improve the reliability of the fan fault detection, avoid the adverse consequences caused by the misjudgment of the fan fault, and avoid affecting the normal operation of the energy storage converter.

[0034] In one embodiment, when the energy storage converter 100 is in the startup state, the PWM signal is a constant PWM signal, and the constant PWM signal has a constant frequency and / or a constant duty cycle, so that the fan 122 runs at a constant speed. The constant speed of the fan 122 is greater than the minimum fault detection speed, and the minimum fault detection speed is determined by the characteristics of the fan 122 itself. For example, the minimum fault detection speed of a certain fan 122 is 20% of the rated speed, which means that only when the fan 122 runs at more than 20% of the rated speed can the correct fan 122 fault be fed back for accurate fault detection.

[0035] In this embodiment, through the constant PWM signal, it is only necessary to monitor the fault feedback signal and ensure that the constant speed of the fan 122 exceeds the minimum fault detection speed, which simplifies the fault detection process and reduces the problem of false alarms caused by low-speed operation. It will not affect the normal operation of the energy storage inverter 100, thereby improving the accuracy and reliability of fault detection.

[0036] In one embodiment, the constant speed of the fan 122 is less than the preset speed to prevent condensation; wherein the preset speed is related to the ambient temperature, ambient humidity and the internal temperature of the device, and the ratio range of the constant speed of the fan 122 to the rated speed of the fan 122 is 25%-50%, so that the fan 122 runs at a lower speed to reduce the risk of condensation in the startup state. For example, if the ambient temperature is high and the ambient humidity is high, and the energy storage converter 100 is in the startup state, the heat generated by the energy storage converter 100 is not very large, and it is possible that the external control humidity is greater than the internal temperature of the device. At this time, if the fan 122 runs at a high speed, a large amount of wet heat control contacts with the internal components of the device with a lower temperature, which is very likely to cause condensation. Therefore, the ratio range of the constant speed of the fan 122 to the rated speed of the fan 122 is set to 25%-50%, that is, by accurately controlling the fan speed in the startup state, while realizing the fault detection of the fan 122, condensation can also be prevented, effectively balancing the fault detection requirements and the anti-condensation requirements, and improving the stability and safety of the operation of the energy storage converter 100.

[0037] In one embodiment, when the energy storage converter 100 is in the startup state, the fault feedback circuit 121 performs fault detection on the fan 122. If the fan 122 fails, the fault feedback circuit 121 sends a fan fault signal. If the fan fault signal does not last for the first preset time, the fault type is most likely a stall, and the stall factor has disappeared. The fan fault signal is cleared and the fan is running again; if the fan fault signal lasts for the first preset time but does not last for the second preset time, the fault type may not be a stall or the stall fault time is long. At this time, a fan fault alarm can be issued, and the maximum power of the energy storage converter 100 is reduced to a set power without directly performing a shutdown operation. Among them, the second preset time is much longer than the first preset time, for example, the second preset time is on the order of days, and the first preset time is on the order of seconds. The control unit is also used to determine whether the fan alarm time exceeds the second preset time. If it exceeds, the energy storage converter is controlled to shut down and the fan fault is recorded.

[0038] Among them, the first preset time can be set to different times according to different energy storage converters 100, and the set power can be set to 80% of the rated power or 60%, which is not specifically limited here. For example, for a large energy storage converter 100, the preset time is set to 5 seconds, and the set power is set to 80% of the rated power. If the fan fault signal does not last for 5 seconds, it is determined that the fault factor (such as the factor causing the stall) disappears; if the fan fault signal lasts for 5 seconds, it is considered that the fan 122 has a continuous stall fault or other faults that are difficult to self-recover. Therefore, the maximum power of the energy storage converter 100 is reduced to 80% of the rated power to ensure the safe operation of the energy storage converter 100 and avoid serious fault problems.

[0039] Specifically, when the energy storage converter 100 is in the startup state, the control unit 13 enables the PWM signal generating circuit 123 and the fault feedback circuit 121, the PWM signal generating circuit 123 provides a PWM signal to the fan 122 to make the fan 122 run, and the fault feedback circuit 121 performs a stall detection on the fan 122. If the fan 122 is stalled, for example, the speed of the fan 122 is lower than the set minimum fault detection speed, the fault feedback circuit 121 sends a fan fault signal to the control unit 13; if the fan fault signal does not last for the first preset time, the control unit 13 determines that the stall factor may be temporary, for example, a foreign object temporarily blocks the fan 122, and then the stall factor disappears, and the fan 122 resumes normal operation. If the fan fault signal persists for a first preset time, the control unit 13 determines that the fan 122 has a persistent stall fault or other faults that are difficult to self-recover, and therefore reduces the maximum power of the energy storage inverter 100 to a set power, so that the energy storage inverter 100 can effectively detect and respond to the fan 122 stall fault during the startup phase, and at the same time take measures to protect the energy storage inverter 100 from damage, thereby ensuring the safety and reliability of the energy storage inverter 100.

[0040] In another embodiment, when the energy storage converter 100 is in the standby state, the control unit 13 enables the fault feedback circuit 121. The standby state includes a first standby stage and a second standby stage. In the first standby stage, the fan 122 is in operation (after the energy storage converter 100 switches from the working state to the standby state, there is a short period of time when the fan runs at a gradually reduced speed until the second standby stage). The fault feedback circuit 121 is used to detect whether the fan 122 is blocked. If the fan 122 is blocked, the fault feedback circuit 121 outputs a fan fault signal. In the second stage, the fan 122 is in a stopped state, and the fault feedback circuit 121 performs fault detection on the fan 122. Because the fan stops in this stage, the faults detected in this stage are mostly hardware faults. If the fan 122 has a hardware fault, the fault feedback circuit 121 outputs a fan fault signal. By detecting different fan faults in different stages of the standby state. It should be noted that hardware fault detection and stall fault detection are also detected by the fault feedback circuit 121. For example, hardware fault problems such as the motor, capacitor, and bearing of the fan 122 can be detected, thereby achieving more comprehensive detection of the fan 122 fault without increasing hardware costs, further improving the reliability and safety of the energy storage inverter 100.

[0041] In another embodiment, the fault feedback circuit 121 is used to send a fan fault signal. When there are multiple fans 122 in the air cooling system 12, each fan 122 is configured with a fault feedback circuit 121, and multiple fault feedback circuits 121 are connected in parallel to obtain a fan fault signal.

[0042] For example, Figure 3 As shown, there are five fans 122 in the air cooling system 12, and each fan 122 is configured with a fault feedback circuit 121. If any fan 122 fails, the fan fault signal FAN(1 / 2 / 3 / 4 / 5)_ERR of the corresponding fan 122 is equal to 1, the corresponding diode (D1 / D2 / D3 / D4 / D5) is turned on, the base of the transistor Q2 is high, the transistor Q2 is turned on, and the fan fault signal FAN_ERR outputs a low level; conversely, if no fan 122 fails, the fan fault signal FAN_ERR of the fan 122 is equal to 0, the diodes are disconnected, the base of the transistor Q2 loses the driving signal, the transistor Q2 is disconnected, and the fan fault signal FAN_ERR outputs a high level.

[0043] Through the fault feedback circuit 121 of the energy storage converter 100 , the fault detection of N fans 122 can be realized, which not only reduces the hardware cost but also prevents false triggering, thereby improving the safety and reliability of the energy storage converter 100 .

[0044] Since the control unit 13 disables the fault feedback circuit 121 when the energy storage converter 100 is in operation, that is, does not perform fault detection, in order to improve the working safety of the energy storage converter 100 and prevent the energy storage converter 100 from overheating due to a fault of the fan 122, in one embodiment, Figure 4 As shown, the energy storage inverter 100 also includes an overheating protection system 14, which includes an overheating feedback circuit 131 connected to the control unit 13. When the energy storage inverter 100 is in working state, the control unit 13 enables the overheating feedback circuit 131, and the overheating feedback circuit 131 is used to send an overheating signal. The control unit 13 can execute an overtemperature protection strategy based on the overheating signal.

[0045] For example, if it is detected that the temperature of the system heating component 11 exceeds a preset safety threshold, the overheating feedback circuit 131 will send an overheating signal to the control unit 13, and the control unit 13 will execute a series of overtemperature protection strategies: cooling system enhancement, derating operation, shutdown protection, alarm notification, etc.

[0046] Therefore, when the energy storage inverter 100 is in working state, although the fan 122 is not detected for fault, based on the overheating protection system 14, when the fan 122 fails or the system heating component 11 overheats, the overheating feedback circuit 131 can send an overheating signal to the control unit 13, thereby executing the overtemperature protection strategy to protect the energy storage inverter 100 from overheating and damage, thereby ensuring the safe operation of the energy storage inverter 100 and extending its service life.

[0047] In one embodiment, the over-temperature protection strategy includes a temperature derating curve, which indicates that the internal temperature of the energy storage converter 100 is negatively correlated with the operating rated power of the energy storage converter 100 . The control unit 13 performs power control according to the temperature derating curve and the detected internal temperature.

[0048] Exemplarily, a temperature derating curve can be set based on a thermal characteristic test of the energy storage inverter 100. The control unit 13 adjusts the output power of the energy storage inverter 100 in real time according to the temperature derating curve and the detected internal temperature. If it is detected that the internal temperature is close to or reaches a preset threshold, the control unit 13 reduces the output power of the energy storage inverter 100 according to the temperature derating curve. If the internal temperature drops and remains within a safe range, the control unit 13 gradually increases the output power of the energy storage inverter 100 until the rated power is reached.

[0049] In this way, it is possible to ensure that the energy storage converter 100 can operate safely even in a high temperature environment, and the impact on system performance can be minimized, thereby improving the working safety of the energy storage converter 100 and extending its service life.

[0050] In another embodiment, the working state of the energy storage inverter 100 includes a full load mode and a low load mode, and the low load mode is enabled when the control unit 13 receives a fan fault signal or an overheating signal. In the low load mode, the energy storage inverter 100 will reduce the output power, for example, below a certain proportion of its rated power, and adjust the working parameters of the energy storage inverter 100 to adapt to low load operation. Thereby reducing the heat generation inside the energy storage inverter 100, reducing the risk of overheating, protecting the internal components of the energy storage inverter 100, and avoiding damage due to overheating.

[0051] In one embodiment, when the energy storage converter 100 is in the standby state, if the fan fault signal continues for a first preset time, it indicates that the fault is difficult to self-recover. At this time, the control unit 13 issues a fan 122 alarm and reduces the maximum power of the energy storage converter 100 to a set power. The range of the set power is 60%-80% of the rated power, and the maximum power is the maximum operating power of the energy storage converter in the working state. For example, if the control unit 13 continuously detects a fan fault signal and exceeds the first preset time, the control unit 13 issues a fan 122 alarm (such as an audible and visual alarm), and the control unit 13 also reduces the power of the energy storage converter 100 to 60%-80% of the rated power to ensure that the energy storage converter 100 can still operate safely in the event of a fan 122 fault, while reducing heat generation, avoiding system overheating, and protecting the energy storage converter 100 from irreversible damage.

[0052] In a specific embodiment, Figure 5As shown, it is a schematic diagram of the process of detecting a fan fault signal by the energy storage converter 100 provided in the present application, which specifically includes the following steps:

[0053] Step S501, the control unit 13 determines whether the energy storage inverter 100 is in one of the standby state, the startup state, and the working state; if the energy storage inverter 100 is in the standby state, execute step S502, if the energy storage inverter 100 is in the startup state, execute step S504, if the energy storage inverter 100 is in the working state, execute step S511.

[0054] Step S502: The control unit 13 activates the fault feedback circuit 121 to continuously detect the fan fault signal.

[0055] Step S503, the control unit 13 determines whether the fan fault signal lasts for a first preset time; if the determination result is yes, step S506 is executed, if the determination result is no, step S502 is repeated.

[0056] In step S504 , the control unit 13 activates the PWM signal generating circuit 123 and the fault feedback circuit 121 . The PWM signal generating circuit 123 uses a constant PWM signal to make the fan 122 run at a constant speed. The fault feedback circuit 121 continuously detects the fan fault signal.

[0057] Step S505, the control unit 13 determines whether the fan fault signal continues for another preset time (the preset time may be the same as the first preset time); if the determination result is yes, execute step S506, if the determination result is no, execute step S509.

[0058] Among them, when the energy storage converter 100 is in the startup state, it mainly detects whether the fan 122 is blocked. The fan 122 is generally blocked by external factors, which may disappear after a period of time. Therefore, the preset time is generally short and can be set to 5 seconds. If the fan fault signal does not last for 5 seconds, it means that the fault is cleared within 5 seconds, such as the blocking factor disappears, the fan 122 fault false alarm is cleared, the fault feedback circuit 121 is falsely triggered, etc. At this time, the energy storage converter 100 is controlled to work normally, thereby preventing the risks caused by false triggering. If the fan fault signal lasts for 5 seconds or more, it means that the fan 122 fault has not been cleared, and the alarm will continue, thereby improving the accuracy of the fault alarm and reducing maintenance costs.

[0059] Step S506: The control unit 13 issues a continuous alarm and reduces the maximum power of the energy storage converter 100 to the set power. The fault at this time is a general fault and can be operated with reduced power.

[0060] Step S507 , the control unit 13 determines whether the fan 122 alarm continues for a second preset time; if the determination result is yes, step S508 is executed, and if the determination result is no, the process ends.

[0061] Among them, the second preset time can be set to one week. If the fan 122 alarm of the energy storage inverter 100 continues for one week, indicating that the fan 122 fault has not been cleared, the energy storage inverter 100 is controlled to shut down, the fan 122 fault is recorded, and the maintenance personnel are reminded to repair it to avoid serious damage.

[0062] Step S508: Control the energy storage converter 100 to shut down to protect the device, and record the fault of the fan 122. The fault at this time is determined to be an irreversible fault, which is a serious fault. The energy storage converter can be further controlled to shut down, and the maintenance personnel should be reminded to perform on-site maintenance.

[0063] Step S509, the control unit 13 determines whether the fan fault signal is cleared for another preset time (the preset time may be the same as the first preset time). If so, it indicates that the fault has been cleared at the moment, and a fault that is difficult to recover from itself has not occurred, and step S510 is executed at this time.

[0064] Step S510: The control unit 13 clears the fan alarm.

[0065] Step S511: The maximum operating power of the energy storage converter 100 may not be reduced.

[0066] Step S512: the control unit 13 controls to clear the previously recorded fan alarm duration, that is, clears the timer compared with the second preset time.

[0067] Step S513 : The control unit 13 disables the fault feedback circuit 121 .

[0068] In summary, the energy storage converter 100 provided in the embodiment of the present application realizes that during the startup process of the energy storage converter 100, a PWM signal is applied to the fan 122 through the PWM signal generating circuit 123, and the fault detection of the fan 122 is performed through the fault feedback circuit 121, and the normal operation of the energy storage converter 100 in other states is not affected, thereby improving the safety of fault detection and reducing hardware costs. Moreover, through the constant PWM signal, it is only necessary to monitor the fault feedback signal and ensure that the constant speed of the fan 122 exceeds the minimum fault detection speed, which simplifies the fault detection process, reduces the problem of false alarms caused by low-speed operation, and does not affect the normal operation of the energy storage converter 100. At the same time, the energy storage converter 100 also includes an overheating protection system 14. After the fan 122 fails or is blocked and the fan 122 cannot rotate, through the temperature protection strategy, it stops working when the temperature is too high and reports temperature-related faults, thereby improving the working safety of the energy storage converter 100.

[0069] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0070] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. An energy storage converter, characterized in that: include: Control unit, air cooling system, system heating components, including: The air cooling system is used for cooling system heat generating components, and comprises: a fan, a fault feedback circuit connected to a control unit, and a PWM signal generating circuit, wherein the fault feedback circuit can send a fan fault signal to the control unit when a fault is detected in the fan; The control unit is used to determine whether the energy storage converter is in one of a standby state, a startup state and a working state, and when the energy storage converter is in the startup state, enable the PWM signal generating circuit and the fault feedback circuit, and when the energy storage converter is in the working state, disable the fault feedback circuit, and the startup state is an intermediate state from the standby state to the working state; Wherein, when the energy storage converter is in the startup state, the PWM signal generating circuit provides a PWM signal to the fan to make the fan run, and the control unit is used for issuing an alarm at least according to the fan fault signal.

2. The energy storage converter according to claim 1, characterized in that: The control unit is used to issue an alarm at least according to the fan fault signal, including the control unit being used to issue an alarm according to the duration of the fan fault signal and a first preset time, and issuing an alarm when the duration of the fan fault signal is greater than the first preset time.

3. The energy storage converter according to claim 2, characterized in that: When the energy storage converter is in the startup state, the PWM signal is a constant PWM signal, and the constant PWM signal has a constant frequency and / or a constant duty cycle, so that the fan runs at a constant speed; Wherein, the constant speed of the fan is greater than a minimum fault detection speed, and the minimum fault detection speed is determined by the characteristics of the fan itself; The constant speed of the fan is less than a preset speed to prevent condensation; wherein the preset speed is related to the ambient temperature, ambient humidity and internal temperature of the device, and the ratio of the constant speed of the fan to the rated speed of the fan is in the range of 25-50%.

4. The energy storage converter according to any one of claims 1 to 3, characterized in that: If the fan fault signal does not last for the first preset time, it is determined that the fault factor disappears and the fan fault signal is cleared; if the fan fault signal lasts for the first preset time, the fan alarm is recorded and the maximum power of the energy storage inverter is reduced to a set power.

5. The energy storage converter according to claim 4, characterized in that: The control unit is further configured to determine whether the fan alarm time exceeds a second preset time, and if so, control the energy storage converter to shut down and record the fan fault.

6. The energy storage converter according to claim 1, characterized in that: When the energy storage converter is in the standby state, the control unit enables the fault feedback circuit; Among them, the standby state includes a first standby stage and a second standby stage. In the first standby stage, the fan is in a running state, and the fault feedback circuit is used to detect whether the fan is blocked. If the fan is blocked, the fault feedback circuit outputs a fan fault signal; in the second stage, the fan is in a stopped state, and the fault feedback circuit performs hardware fault detection on the fan. If the fan has a hardware fault, the fault feedback circuit outputs a fan fault signal.

7. The energy storage converter according to any one of claims 1 to 3, characterized in that: The fault feedback circuit is used to send a fan fault signal. When there are multiple fans in the air cooling system, each fan is configured with a fault feedback circuit, and multiple fault feedback circuits are connected in parallel to obtain a fan fault signal.

8. The energy storage converter according to any one of claims 1 to 3, characterized in that: It also includes an overheating protection system, which includes an overheating feedback circuit connected to the control unit. When the energy storage inverter is in the working state, the control unit enables the overheating feedback circuit, and the overheating feedback circuit is used to send an overheating signal. The control unit can execute an overtemperature protection strategy based on the overheating signal.

9. The energy storage converter according to claim 8, characterized in that: The over-temperature protection strategy includes a temperature derating curve, the temperature derating curve indicates that the internal temperature of the energy storage converter is negatively correlated with the operating rated power of the energy storage converter, and the control unit performs power control according to the temperature derating curve and the detected internal temperature; Alternatively, the working state of the energy storage converter includes a full load mode and a low load mode, and the low load mode is enabled when the control unit receives the fan fault signal or the overheating signal.

10. The energy storage converter according to claim 1, characterized in that: When the energy storage converter is in standby mode, if the fan fault signal lasts for a first preset time, the control unit issues a fan alarm and reduces the maximum power of the energy storage converter to a set power, wherein the set power ranges from 60% to 80% of the rated power.

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