Energy storage converter control system device and control method

Abstract

The invention relates to the technical field of energy storage converter control systems, and discloses an energy storage converter control system device. Comprising a power supply circuit module, a three-phase three-level IGBT drive circuit module, a simulation and conditioning circuit module, a metering circuit module, a main processor module, an isolation communication module, a communication processor module, a coprocessor module and a control interface module. According to the invention, by adding a metering sampling channel and a metering calculation function, a coprocessor is used for calculation, the burden of a main processor DSP is reduced, a power correction large closed-loop algorithm is added to software, and the problem that the output power of an energy storage converter is different from the metering value of an ammeter is solved, so that the countercurrent problem of an energy storage system and the problem that the energy storage system cannot be fully charged within limited time are solved; an alternating current and direct current dual power supply strategy is adopted, it is guaranteed that control power cannot be powered off in the power grid power failure or battery side tripping state in the operation process of the energy storage converter, the explosion risk caused by power failure is avoided, and the purpose of high-precision output is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of energy storage converter control systems, and in particular to an energy storage converter control system device and a control method. Background Art

[0002] The large-scale grid-connected operation of new energy in my country mainly relies on regulating and supporting power sources such as thermal power, hydropower, pumped storage, and the coordinated support of large power grids. That is, traditional power sources currently bear the main responsibility for online electricity and supply security. After the proportion of power generation exceeds 15%, the safe operation and efficient utilization of new energy will face greater challenges. As the proportion of new energy installed capacity and electricity continues to increase, the gap in regulating and supporting power sources is getting bigger and bigger, and it is necessary to deploy a high proportion of flexible resources and active support resources to cope with it.

[0003] Energy storage inverters are key components between energy storage devices and power grids and are irreplaceable. In recent years, supported by policies, the scale of chemical energy storage in my country has continued to grow, driving the market demand for energy storage inverters to rise and the market size to continue to expand. In terms of production, the current domestic energy storage inverter market concentration is relatively high, but because the market has not yet been fully developed, there are still huge development opportunities for the energy storage inverter industry in the future.

[0004] The energy storage inverter is composed of a DC / AC bidirectional conversion module, a core control unit, etc. The energy storage inverter receives control instructions through remote communication, and remote commands control the inverter to charge and discharge, thereby realizing the regulation of active power and reactive power of the power grid.

[0005] Existing solutions (such as Figure 4 ) Generally, the control command is sent remotely from the background to the energy storage converter communication module, and then the command is forwarded to the core processor DSP to realize the switch and power setting. The DSP detects the voltage, current and frequency signals in real time through the analog circuit acquisition module. After calculation, the voltage outer loop adopts the PI controller, and the dq current reference value is calculated during PQ control. The current inner loop adopts the PI controller, dq current decoupling, grid voltage feedforward, and three-level SVPWM space vector modulation, including midpoint potential balance control, and a phase-locked loop (based on a single synchronous rotating coordinate system, a phase-locked loop SRF-PLL) to adjust the SVPWM signal so that the output power and voltage and current parameters are consistent with the given values. In the existing scheme, the output power is too dependent on the sampling accuracy of the analog circuit and the measurement algorithm of the DSP. When the current and voltage waveforms are relatively stable, it can generally maintain a high output accuracy. However, when the given power is too small or the grid harmonics are large, the DSP calculated power will be different from the metered value, resulting in reverse flow or insufficient charging. Therefore, there is an urgent need to improve the energy storage converter control system device and control method in this field to solve the defects of the prior art. Summary of the invention

[0006] In view of the deficiencies in the prior art, the present invention provides an energy storage inverter control system device and control method to solve the backflow problem of the energy storage system and the problem of not being fully charged within a limited time, while avoiding the risk of explosion and achieving the purpose of high-precision output.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] In a first aspect, the present invention discloses a control system device for an energy storage converter, comprising a power supply circuit module, a three-phase three-level IGBT drive circuit module, an analog and conditioning circuit module, a metering circuit module, a main processor module, an isolated communication module, a communication processor module, a coprocessor module and a control interface module.

[0009] Preferably, the power supply circuit module includes a power input of DC1500V or AC690V, outputs low-voltage 15V and 24V power supplies, and further outputs 5V, + / -12V, 3.3V, 1.2V, and 7V power supplies. The input power supply is a battery with a maximum DC voltage of DC1500, or an AC side input three-phase voltage of AC690V. After passing through an isolation and step-down circuit, a DC24V power supply is output and input to a control interface module, and a DC15V power supply is output and input to a three-phase three-level IGBT drive circuit module. In addition, after stepping down, 5V, + / -12V, 3.3V, 1.2V, and 7V power supplies are output and provided to the control circuit for use.

[0010] Preferably, the three-phase three-level IGBT drive circuit module includes a drive signal logic control circuit and a three-level IGBT drive circuit. The drive signal logic control circuit receives the SVPWM signal from the main processor module, receives the analog fault signal input from the analog and conditioning circuit module, receives the fault envelope signal input from the coprocessor module, inputs it into the three-level IGBT drive circuit, and outputs it to the coprocessor module after receiving the drive fault signal.

[0011] Preferably, the analog and conditioning circuit modules include an analog circuit, a conditioning circuit, and an analog fault protection circuit. The voltage and current signals collected from the high-voltage end are stepped down into low-voltage signals by the analog circuit, and are adjusted into voltage signals recognizable by the controller by the conditioning circuit. The signals are then input into the metering circuit module, the main processor module, and the analog fault protection circuit respectively. The analog fault protection circuit determines at the hardware level whether the collected signal reaches the alarm value and then outputs it to the three-phase three-level IGBT drive circuit module.

[0012] Preferably, the metering circuit module includes a metering chip, and the signal input from the analog and conditioning circuit module is converted into power and electric quantity signal after passing through the metering chip, and output to the isolation communication module.

[0013] Preferably, the isolation communication module includes an isolation optocoupler, optocoupler 1 receives the signal input from the metering circuit module and outputs it to the communication processor module, optocoupler 2 receives the CAN signal input from the main processor module and outputs it to the communication processor module, optocoupler 3 receives the RS485 signal input from the main processor module and outputs it to the communication processor module, and optocoupler 4 receives the switch signal input from the main processor module and outputs it to the communication processor module.

[0014] Preferably, the communication processor module includes a coprocessor ARM, wireless network, Bluetooth, RS485, CAN, Ethernet and a coprocessor ARM chip, receives the signal input by the isolation communication module, converts it into wireless network, Bluetooth, RS485, CAN or Ethernet signals through a serial communication protocol, and communicates with an external energy storage system and a monitoring background.

[0015] Preferably, the coprocessor module includes a coprocessor ARM, and the coprocessor ARM chip communicates with the main processor DSP using CAN and serial bus communication protocols. The external switch quantity passes through the isolation communication module optocoupler 4 to the communication processor module. The coprocessor ARM chip controls the operation and stop of the relay, contactor, and cooling fan respectively, and receives feedback signals. The coprocessor ARM chip receives the status of the status switch.

[0016] Preferably, the control interface module comprises a relay, a contactor, a cooling fan and a status switch, and the relay, the contactor, the cooling fan and the status switch receive control from the coprocessor ARM chip and output a status signal to the coprocessor ARM chip.

[0017] In a second aspect, the present invention discloses a control method for an energy storage converter control system, comprising the above-mentioned energy storage converter control system device, the method comprising: an instruction issued by the background passes through a communication module to determine whether to turn on or off the machine and set the power, and then transmits the power-on command to a main controller, the main controller collects whether the current state meets the power-on conditions through an analog circuit and a conditioning circuit, assigns values ​​to the coordinate transformation after the self-check passes, calculates the voltage feedforward D, Q values, performs a current inner loop PI control, performs a coordinate inverse transformation, inputs an SVPWM module, performs narrow pulse limitation, and outputs an SVPWM pulse to a drive circuit, the state switch detects the current state and outputs it to a coprocessor, the coprocessor performs a fault judgment and outputs it to the drive circuit, if a fault is detected, the pulse is blocked, after stable operation, the analog circuit collects the current voltage and current state, and outputs it to a metering chip after passing the conditioning circuit, the metering chip performs calculations, and outputs the calculated value to the communication module, and after comparing it with the current given value, corrects the instruction parameter to the main controller, so that the output parameter of the energy storage converter is consistent with the given value.

[0018] In view of the deficiencies of the prior art, the present invention provides an energy storage converter control system device and a control method, which overcome the deficiencies of the prior art. The beneficial effects of the present invention are:

[0019] 1. In the present invention, by adding a metering sampling channel, the metering calculation function uses a coprocessor to do the calculation, which reduces the burden of the main processor DSP, and the software adds a power correction large closed-loop algorithm to solve the problem of the difference between the output power of the energy storage inverter and the metered value, thereby solving the problem of reverse flow of the energy storage system and the problem of inability to fully charge within a limited time.

[0020] 2. In the present invention, an AC / DC dual power supply strategy is adopted to ensure that the control power will not be cut off when a power outage occurs in the power grid during the operation of the energy storage converter, or when the battery side trips, thereby avoiding the risk of explosion.

[0021] 3. In the present invention, a high-power closed-loop control strategy is introduced to enable the energy storage converter to achieve high-precision output in a poor power grid environment or a low output power environment.

[0022] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention.

[0024] Figure 1 It is the overall system block diagram of the present invention;

[0025] Figure 2 It is a system block diagram of the operation process in the present invention;

[0026] Figure 3 This is a block diagram of the closed-loop process system of the metering chip in the present invention;

[0027] Figure 4 This is the control system block diagram of the existing solution.

[0028] In the figure: 10, power supply circuit module; 20, three-phase three-level IGBT drive circuit module; 30, analog and conditioning circuit module; 40, metering circuit module; 50, main processor module; 60, isolated communication module; 70, communication processor module; 80, coprocessor module; 90, control interface module. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] Embodiment 1

[0031] See also Figure 1-Figure 4 A storage converter control system device includes a power supply circuit module 10, a three-phase three-level IGBT drive circuit module 20, an analog and conditioning circuit module 30, a metering circuit module 40, a main processor module 50, an isolated communication module 60, a communication processor module 70, a coprocessor module 80 and a control interface module 90.

[0032] As a technical optimization scheme of the present invention, the power circuit module 10 includes a power input of DC1500V or AC690V, outputs low-voltage 15V and 24V power, and further outputs 5V, + / -12V, 3.3V, 1.2V, and 7V power. The input power is a battery with a maximum DC voltage of DC1500, or an AC side input three-phase voltage of AC690V. After passing through an isolation step-down circuit, a DC24V power supply is output and input to the control interface module 90, and a DC15V power supply is output and input to the three-phase three-level IGBT drive circuit module 20. In addition, after step-down, 5V, + / -12V, 3.3V, 1.2V, and 7V power supplies are output and provided to the control circuit for use.

[0033] As a technical optimization solution of the present invention, the three-phase three-level IGBT drive circuit module 20 includes a drive signal logic control circuit and a three-level IGBT drive circuit. The drive signal logic control circuit receives the SVPWM signal from the main processor module 50, receives the analog fault signal input by the analog and conditioning circuit module 30, receives the fault envelope signal input from the coprocessor module 80, inputs it into the three-level IGBT drive circuit, and outputs it to the coprocessor module 80 after receiving the drive fault signal.

[0034] As a technical optimization solution of the present invention, the analog and conditioning circuit module 30 includes an analog circuit, a conditioning circuit, and an analog fault protection circuit. The voltage and current signals collected from the high-voltage end are stepped down into low-voltage signals by the analog circuit, and are adjusted into voltage signals recognizable by the controller after being adjusted by the conditioning circuit. The signals are then input into the metering circuit module 40, the main processor module 50, and the analog fault protection circuit respectively. The analog fault protection circuit determines at the hardware level whether the collected signal reaches the alarm value and then outputs it to the three-phase three-level IGBT drive circuit module 20.

[0035] As a technical optimization solution of the present invention, the metering circuit module 40 includes a metering chip. The signal input from the analog and conditioning circuit module 30 is converted into a power and electric quantity signal after passing through the metering chip and output to the isolation communication module 60 .

[0036] As a technical optimization solution of the present invention, the isolation communication module 60 includes an isolation optocoupler, optocoupler 1 receives the signal input by the metering circuit module 40 and outputs it to the communication processor module 70, optocoupler 2 receives the CAN signal input by the main processor module 50 and outputs it to the communication processor module 70, optocoupler 3 receives the RS485 signal input by the main processor module 50 and outputs it to the communication processor module 70, and optocoupler 4 receives the switch signal input by the main processor module 50 and outputs it to the communication processor module 70.

[0037] As a technical optimization solution of the present invention, the communication processor module 70 includes a coprocessor ARM, wireless network, Bluetooth, RS485, CAN, Ethernet and a coprocessor ARM chip, receives the signal input by the isolation communication module 60, converts it into wireless network, Bluetooth, RS485, CAN or Ethernet signals through a serial communication protocol, and communicates with an external energy storage system and a monitoring background.

[0038] As a technical optimization solution of the present invention, the coprocessor module 80 includes a coprocessor ARM. The coprocessor ARM chip communicates with the main processor DSP using CAN and serial bus communication protocols. The external switching quantity passes through the isolation communication module 60 optocoupler 4 to the communication processor module 70. The coprocessor ARM chip controls the operation and stop of the relay, contactor, and cooling fan respectively, and receives feedback signals. The coprocessor ARM chip receives the status of the status switch.

[0039] As a technical optimization solution of the present invention, the control interface module 90 includes relays, contactors, cooling fans and status switches. The relays, contactors, cooling fans and status switches receive control from the coprocessor ARM chip and output status signals to the coprocessor ARM chip.

[0040] Embodiment 2

[0041] A control method for an energy storage converter control system includes the energy storage converter control system device in the first embodiment. The method comprises: an instruction sent from a background passes through a communication module to determine whether to turn on or off the machine and set the power, and then transmits the power-on command to a main controller. The main controller collects whether the current state meets the power-on condition through an analog circuit and a conditioning circuit. After the self-check is passed, the coordinate transformation is assigned, the voltage feedforward D, Q value calculation is performed, and after the current inner loop PI control, the coordinate inverse transformation is performed, and the SVPWM module is input, and after narrow pulse limitation, the SVPWM pulse is output to the drive circuit. The state switch detects the current state and outputs it to a coprocessor. After the coprocessor performs fault judgment, the output is output to the drive circuit. If a fault is detected, the pulse is blocked. After stable operation, the analog circuit collects the current voltage and current state, and outputs it to a metering chip after passing the conditioning circuit. After the metering chip performs calculation, the calculated value is output to the communication module. After comparison with the current given value, the instruction parameter is corrected to the main controller, so that the output parameter of the energy storage converter is consistent with the given value.

[0042] Among them, all the above-mentioned electrical products can be purchased on the market. They are mature technologies and have been fully disclosed, so they will not be repeated in the specification.

[0043] Finally, it should be noted that in the description of the present invention, it should be noted that the terms "vertical", "up", "down", "horizontal", etc. indicate orientations or positional relationships 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.

[0044] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0045] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention is described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An energy storage converter control system device, characterized in that: The invention comprises a power circuit module (10), a three-phase three-level IGBT drive circuit module (20), an analog and conditioning circuit module (30), a metering circuit module (40), a main processor module (50), an isolated communication module (60), a communication processor module (70), a coprocessor module (80) and a control interface module (90).

2. An energy storage converter control system device according to claim 1, characterized in that: The power circuit module (10) includes a power input of DC1500V or AC690V, outputs low-voltage 15V and 24V power, and further outputs 5V, + / -12V, 3.3V, 1.2V, and 7V power. The input power is a battery with a maximum DC voltage of DC1500, or an AC side input three-phase voltage of AC690V. After passing through an isolation step-down circuit, a DC24V power is output and input to a control interface module (90), and a DC15V power is output and input to a three-phase three-level IGBT drive circuit module (20). In addition, after stepping down, 5V, + / -12V, 3.3V, 1.2V, and 7V power are output and provided to the control circuit for use.

3. The energy storage converter control system device according to claim 1, characterized in that: The three-phase three-level IGBT drive circuit module (20) comprises a drive signal logic control circuit and a three-level IGBT drive circuit. The drive signal logic control circuit receives an SVPWM signal from a main processor module (50), receives an analog fault signal input from an analog and conditioning circuit module (30), receives a fault envelope signal input from a coprocessor module (80), inputs the signal into the three-level IGBT drive circuit, and outputs the drive fault signal to the coprocessor module (80) after receiving the drive fault signal.

4. The energy storage converter control system device according to claim 1, characterized in that: The simulation and conditioning circuit module (30) comprises a simulation circuit, a conditioning circuit, and a simulation fault protection circuit. The voltage and current signals collected from the high-voltage end are stepped down into low-voltage signals by the simulation circuit, and are regulated into voltage signals recognizable by the controller by the conditioning circuit. The signals are then input into the metering circuit module (40), the main processor module (50), and the simulation fault protection circuit respectively. The simulation fault protection circuit determines at the hardware level whether the collected signals reach the alarm value and then outputs the signals to the three-phase three-level IGBT drive circuit module (20).

5. The energy storage converter control system device according to claim 1, characterized in that: The metering circuit module (40) comprises a metering chip, and the signal input from the analog and conditioning circuit module (30) is converted into power and electric quantity signals after passing through the metering chip, and is output to the isolation communication module (60).

6. The energy storage converter control system device according to claim 1, characterized in that: The isolation communication module (60) comprises an isolation optical coupler, wherein the optical coupler 1 receives a signal input from the metering circuit module (40) and outputs it to the communication processor module (70), the optical coupler 2 receives a CAN signal input from the main processor module (50) and outputs it to the communication processor module (70), the optical coupler 3 receives an RS (485) signal input from the main processor module (50) and outputs it to the communication processor module (70), and the optical coupler 4 receives a switch signal input from the main processor module (50) and outputs it to the communication processor module (70).

7. The energy storage converter control system device according to claim 1, characterized in that: The communication processor module (70) comprises a coprocessor ARM, wireless network, Bluetooth, RS485, CAN, Ethernet and a coprocessor ARM chip, receives a signal input by the isolation communication module (60), converts it into a signal such as a wireless network, Bluetooth, RS485, CAN or Ethernet through a serial communication protocol, and communicates with an external energy storage system and a monitoring background.

8. The energy storage converter control system device according to claim 1, characterized in that: The coprocessor module (80) comprises a coprocessor ARM. The coprocessor ARM chip communicates with the main processor DSP using CAN and serial bus communication protocols. External switch quantities are transmitted through the isolation communication module (60) optical coupler 4 to the communication processor module (70). The coprocessor ARM chip controls the operation and stop of the relay, contactor, and cooling fan respectively, and receives feedback signals. The coprocessor ARM chip receives the status of the status switch.

9. The energy storage converter control system device according to claim 1, characterized in that: The control interface module (90) comprises a relay, a contactor, a cooling fan and a status switch, wherein the relay, the contactor, the cooling fan and the status switch receive control from the coprocessor ARM chip and output a status signal to the coprocessor ARM chip.

10. A control method for an energy storage converter control system, characterized in that: The invention comprises the energy storage converter control system device as described in claim 1 above, wherein the method is as follows: the command sent by the background passes through the communication module to determine whether to turn on and off the machine and set the power, and then transmits the power-on command to the main controller, the main controller collects whether the current state meets the power-on conditions through the analog circuit and the conditioning circuit, assigns the coordinate transformation after the self-check, calculates the voltage feedforward D, Q value, performs the coordinate inverse transformation after the current inner loop PI control, inputs the SVPWM module, outputs the SVPWM pulse to the drive circuit after narrow pulse limitation, the state switch detects the current state and outputs it to the coprocessor, the coprocessor performs fault judgment and outputs it to the drive circuit, if a fault is detected, the pulse is blocked, after stable operation, the analog circuit collects the current voltage and current state, outputs it to the metering chip after passing the conditioning circuit, the metering chip performs calculation, outputs the calculated value to the communication module, compares it with the current given value, and corrects the instruction parameter to the main controller, so that the output parameter of the energy storage converter is consistent with the given value.

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