Safety detection device of energy storage converter

Abstract

The utility model relates to the technical field of energy conversion, and discloses a safety detection device of an energy storage converter, which comprises a main control module, a communication module, a voltage monitoring module and a current monitoring module. The output end of the main control module is connected with the communication module; the communication module is connected with an upper BMS master controller of the energy storage power station. The input end of the voltage monitoring module is connected with the input end and the output end of the PCS. The input end of the current monitoring module is connected with the input end and the output end of the PCS; the output ends of the voltage monitoring module and the current monitoring module are connected with the input end of the main control module; the voltage monitoring module comprises a voltage signal conditioning circuit; the current monitoring module comprises a current signal conditioning circuit. According to the utility model, additional safety monitoring can be carried out on the PCS of the energy storage station, and severe consequences caused by network or physical targeted attacks of the energy storage station can be prevented.

Description

Technical Field

[0001] The utility model relates to the technical field of energy conversion, in particular to a safety detection device for an energy storage converter. Background Art

[0002] The primary function of a PCS (Power Conversion System) energy storage converter is to convert direct current (DC) in the energy storage system into alternating current (AC) for use in the grid, or vice versa. It acts as a bridge between renewable energy generation and the grid, ensuring efficient conversion between different power forms. It also supports frequency and peak regulation, enhancing grid stability and flexibility.

[0003] Existing PCSs typically employ single or dual closed-loop control strategies to ensure that the output voltage and current conform to the grid-connected size and waveform, ensuring that energy can flow smoothly into the larger power grid system. This also keeps the voltage on the energy storage battery stable, preventing overvoltage or overcurrent during battery charging and discharging. However, attacks at the physical communication or network security levels during energy demand transmission can cause the upper-level control logic to receive erroneous status information and issue incorrect instructions. For example, if the energy storage battery voltage has reached full charge but the stop charging signal is still processed as continuing charging, the battery will overcharge, resulting in catastrophic consequences. Similarly, if energy continues to flow to the grid when there is a large amount of idle energy, the grid frequency will fluctuate and even cause node loss. Therefore, safety testing and verification of the PCS's supporting control circuits are crucial and necessary. Utility Model Content

[0004] The purpose of this utility model is to provide a safety detection device for an energy storage converter, which can perform additional safety monitoring on the PCS of an energy storage station to prevent the energy storage station from causing adverse consequences due to network or physical targeted attacks.

[0005] In order to achieve the above-mentioned objectives, the present invention provides a safety detection device for an energy storage converter, comprising a main control module, a communication module, a voltage monitoring module, and a current monitoring module; the output end of the main control module is connected to the communication module; the communication module is connected to the upper-level BMS main control of the energy storage power station, the input end of the voltage monitoring module is connected to the input end and output end of the PCS; the input end of the current monitoring module is connected to the input end and output end of the PCS; the output ends of the voltage monitoring module and the current monitoring module are connected to the input end of the main control module; the voltage monitoring module includes a voltage signal conditioning circuit; the current monitoring module includes a current signal conditioning circuit.

[0006] In some embodiments, the voltage monitoring module includes a first voltage monitoring module and a second voltage monitoring module; the input end of the first voltage monitoring module is connected to the input end of the PCS, and the input end of the second voltage monitoring module is connected to the output end of the PCS; the output ends of the first and second voltage monitoring modules are both connected to the input end of the main control module;

[0007] The current monitoring module includes a first and a second current monitoring module; the input end of the first current monitoring module is connected to the input end of the PCS, and the input end of the second current monitoring module is connected to the output end of the PCS; the output ends of the first and second current monitoring modules are both connected to the input end of the main control module.

[0008] In some embodiments, the main control module adopts an MSP430 microcontroller.

[0009] In some embodiments, the communication module uses CAN bus communication.

[0010] In some embodiments, the input end of the voltage monitoring module adopts an external snap-on VT.

[0011] In some embodiments, the input end of the current monitoring module adopts an external snap-on CT.

[0012] The embodiment of the utility model provides a safety detection device for an energy storage converter. Compared with the prior art, the beneficial effects thereof are:

[0013] Both voltage and current detection modules utilize external sensors, eliminating the need for direct electrical connection to the energy storage circuit via wires or other wired methods. This eliminates the need for wiring changes or power connections after the energy storage station is constructed, making it safe and convenient. These external voltage and current sensors can be considered redundant sensors for the PCS, making them less vulnerable to external network or physical attacks. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a schematic structural diagram of a safety detection device for an energy storage converter provided by an embodiment of the present utility model;

[0015] Figure 2 This is a circuit diagram of a safety detection device for an energy storage converter provided by an embodiment of the utility model. DETAILED DESCRIPTION

[0016] To make the above-mentioned objects, features, and advantages of the present invention more clearly understood, the following detailed description of specific embodiments of the present invention is provided in conjunction with the accompanying drawings. The following description sets forth many specific details to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art may make similar modifications without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0017] In the description of the present invention, it should be understood that the terms "length", "width", "up", "down", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.

[0018] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature specified as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of this utility model, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0019] like Figure 1 As shown, a safety detection device for an energy storage converter in a preferred embodiment of the present invention includes a main control module 1, a communication module 2, a voltage monitoring module 3, and a current monitoring module 4; the output end of the main control module 1 is connected to the communication module 2; the communication module 2 is connected to the upper-level BMS main control of the energy storage power station, the input end of the voltage monitoring module 3 is connected to the input end and output end of the PCS; the input end of the current monitoring module 4 is connected to the input end and output end of the PCS; the output ends of the voltage monitoring module 3 and the current monitoring module 4 are connected to the input end of the main control module 1; the voltage monitoring module 3 includes a voltage signal conditioning circuit; the current monitoring module 4 includes a current signal conditioning circuit.

[0020] In a specific embodiment, the voltage monitoring module includes a first voltage monitoring module and a second voltage monitoring module; the input end of the first voltage monitoring module is connected to the input end of the PCS, and the input end of the second voltage monitoring module is connected to the output end of the PCS; the output ends of the first and second voltage monitoring modules are both connected to the input end of the main control module;

[0021] The current monitoring module includes a first and a second current monitoring module; the input end of the first current monitoring module is connected to the input end of the PCS, and the input end of the second current monitoring module is connected to the output end of the PCS; the output ends of the first and second current monitoring modules are both connected to the input end of the main control module.

[0022] like Figure 2 As shown, in a specific implementation, the first voltage monitoring module samples the voltage at the input end of the PCS to obtain a voltage signal U1, and the second voltage monitoring module samples the voltage at the output end of the PCS to obtain a voltage signal U2; the voltage signal conditioning circuit conditions the voltage signals U1 and U2 to improve the accuracy of the voltage signal, and outputs the conditioned voltage analog signal to the main control module 1 after analog-to-digital conversion. The main control module 1 calculates the power value of the converted voltage signal and detects the waveform timing to obtain the power value flow and voltage waveform of the voltage, and uploads the power value flow and voltage waveform of the voltage to the upper-level BMS main control of the energy storage power station through the communication module 2, and compares them with the power control command received by the upper-level control system of the energy storage power station; if the power value flow of the voltage or the generated voltage waveform is significantly different from the power frequency signal of the power grid, an attack alarm is triggered, and the power flow value calculated by itself is uploaded to the upper-level control system for verification.

[0023] Similarly, the first current monitoring module samples the current at the input end of the PCS to obtain the current signal I1, and the second current monitoring module samples the current at the output end of the PCS to obtain the current signal I2. The current signal conditioning circuit conditions the current signals I1 and I2 to improve the accuracy of the current signals, converts the conditioned current analog signals into digital signals, and outputs them to the main control module 1. The main control module 1 calculates the power of the converted current signal and detects the waveform timing to obtain the current power value flow and current waveform. The current power value flow and current waveform are uploaded to the upper-level BMS main control of the energy storage power station through the communication module 2 and compared with the power control command received by the upper-level control system of the energy storage power station. If the current power value flow or the generated current waveform is significantly different from the power frequency signal of the power grid, an attack alarm is triggered, and the calculated power flow value is uploaded to the upper-level control system for verification. Among them, the second voltage monitoring module on the AC side has a mutual inductance isolation function, which can perform AC measurement and prevent interference from power frequency electromagnetic signals through its own optocoupler isolation function, thereby improving accuracy and safety.

[0024] In a specific embodiment, the main control module adopts an MSP430 single chip microcomputer.

[0025] It's worth noting that the MSP430 microcontroller is a mixed-signal processor with a 16-bit computing framework and a reduced instruction set. It boasts high computing power while maintaining extremely low power consumption. The microcontroller incorporates a built-in power calculation algorithm and a self-learning attack detection algorithm. While automatically calculating the PCS output voltage and current curves, it also establishes a model of the protected PCS's operating conditions. It uses a timing method to capture the power conversion curve characteristics under normal operating conditions. In the event of an attack, it compares the PCS output changes with the charge and discharge instructions from the energy storage power station's upper-level server, ensuring safety detection after the attack. Upon detecting an attack, an alarm is issued and reported to the upper-level server via the communication module. Simultaneously, the optocoupler relay built into the current monitoring module disconnects the PCS from the grid and battery to prevent an incident.

[0026] In a specific embodiment, the communication module adopts CAN bus communication.

[0027] It is understandable that CAN bus communication has a high transmission speed and data volume, which enables the safety detection device to communicate quickly with the main control layer of the energy storage power station, ensuring smooth operation of the system.

[0028] In a specific embodiment, the input end of the voltage monitoring module adopts an external snap-on VT.

[0029] It should be noted that the snap-on VT, as a sensor input, can convert high voltage into a low voltage that can be converted to analog. Furthermore, the VT sensor is highly portable and reliable, requiring no electrical connection to the PCS to collect voltage signals. The VT sensor can also monitor the AC grid-side voltage in real time, eliminating the need for subsequent timing processing and reducing the computational burden on the main control module 1.

[0030] In a specific embodiment, the input end of the current monitoring module adopts an external snap-on CT.

[0031] It's important to note that the snap-on CT, as the sensor input, converts high current into a low voltage that can be converted to analog. Furthermore, the CT offers high portability and reliability as a sensor, requiring no electrical connection to the PCS to collect current signals. Furthermore, a relay device based on optocoupler signals is connected in series with the CT sensor to prevent interference from electromagnetic signals that could affect the safety detection device.

[0032] In summary, the embodiment of the present invention provides a safety detection device for an energy storage converter, in which both the voltage and current detection modules use external sensor devices, and do not need to be directly electrically connected to the energy storage electrical circuit through wires or other wired means. After the construction of the energy storage power station is completed, no line changes, power connections, and other operations are required, which is safe and convenient. The snap-on sensor design can be deployed on different models of energy storage equipment, has a wide range of applications, and does not require additional circuit design. The external voltage and current sensors can be regarded as redundant sensors of the PCS, and are not susceptible to attacks from the external network or physical level. The main control module is a low-power processing chip MSP430, which can use the built-in battery of the safety detection device for power supply or can be connected to weak current for power supply. The power supply method is flexible and stable, and the standby time is long, which can effectively ensure the operational stability and sustainability of the safety detection device. The adopted attack detection algorithm does not require improvement and combination of the existing PCS control algorithm and power control strategy, and can be directly added to the safety detection device as a software patch.

[0033] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and replacements can be made without departing from the technical principles of the present invention. These improvements and replacements should also be regarded as the scope of protection of the present invention.

Claims

1. A safety detection device for an energy storage converter, characterized in that: It includes a main control module, a communication module, a voltage monitoring module, and a current monitoring module; the output end of the main control module is connected to the communication module; the communication module is connected to the upper-level BMS main control of the energy storage power station, the input end of the voltage monitoring module is connected to the input and output ends of the PCS; the input end of the current monitoring module is connected to the input and output ends of the PCS; the output ends of the voltage monitoring module and the current monitoring module are connected to the input end of the main control module; the voltage monitoring module includes a voltage signal conditioning circuit; the current monitoring module includes a current signal conditioning circuit.

2. The safety detection device for energy storage converter according to claim 1, characterized in that: The voltage monitoring module includes a first voltage monitoring module and a second voltage monitoring module; the input end of the first voltage monitoring module is connected to the input end of the PCS, and the input end of the second voltage monitoring module is connected to the output end of the PCS; the output ends of the first and second voltage monitoring modules are both connected to the input end of the main control module; The current monitoring module includes a first and a second current monitoring module; the input end of the first current monitoring module is connected to the input end of the PCS, and the input end of the second current monitoring module is connected to the output end of the PCS; the output ends of the first and second current monitoring modules are both connected to the input end of the main control module.

3. The safety detection device for energy storage converter according to claim 1, characterized in that: The main control module adopts MSP430 single chip microcomputer.

4. The safety detection device for an energy storage converter according to claim 1, wherein: The communication module adopts CAN bus communication.

5. The safety detection device for energy storage converter according to claim 1, characterized in that: The input end of the voltage monitoring module adopts an external snap-on VT.

6. The safety detection device for energy storage converter according to claim 1, characterized in that: The input end of the current monitoring module adopts an external snap-on CT.

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