Method and device for detecting insulation resistance of energy storage system, electronic equipment and storage medium

Abstract

The invention discloses an energy storage system insulation resistance detection method and device, electronic equipment and a storage medium, and the method comprises the steps: employing an adjustable constant current source structure and a capacitance compensation circuit according to a dynamic compensation current unit, and achieving the dynamic compensation of a current in an energy storage system; according to the multi-band signal injection unit, a frequency sweep circuit is adopted to realize frequency sweep; and according to a cooperative control unit, cooperative control of the dynamic compensation current unit and the multi-band signal injection unit is adopted to realize insulation impedance detection. Through cooperative detection of the insulation impedance of the energy storage system based on dynamic direct current injection and capacitance compensation, the frequency sweeping technology is combined with dynamic current compensation, Y capacitance interference is solved, and the problem of signal crosstalk is solved through cooperative control.

Description

Technical Field

[0001] The present application relates to the technical field of energy storage systems, and in particular to a method, device, electronic equipment, and storage medium for detecting insulation impedance of an energy storage system. Background Art

[0002] In non-isolated energy storage systems below 1500V, the Y capacitors on the PCS side are coupled to the battery system. High-frequency charging and discharging causes the bridge detection signal to be shunted, leading to false insulation alarms. To address this, a related art provides an insulation detection circuit and method for systems below 1500V. This method uses a multi-channel resistor module in parallel with a switch structure. By switching the resistor branches, two detection states are generated. The measured voltage uses a voltage divider formula to dynamically offset battery voltage fluctuations.

[0003] When multiple modules are connected in parallel, the insulation impedance of the BMS detection circuit is artificially low due to the superposition of parallel impedance. In this regard, the relevant technology provides a device and method for measuring the insulation resistance of the battery pack by using a negative pole relay. This method adopts a time-sharing multiplexing detection strategy, controls the relay timing through the MCU, completes insulation sampling in the module switching gap, and avoids the superposition of parallel impedance.

[0004] However, in related technologies, the Y capacitors on the DC side of the PCS (energy storage converter) to the ground form a high-frequency charging and discharging loop during the bridge method detection process, causing the detection signal to be shunted and mistakenly judged as low insulation impedance. Especially in non-isolated systems, the Y capacitors on the mains side are coupled with the battery system, exacerbating the high-frequency harmonic penetration effect, causing the insulation resistance detection error to reach more than 50%. However, in hybrid energy systems, the carrier communication signals of different devices overlap with the insulation detection signal frequency bands, causing crosstalk. At the same time, existing detection algorithms rely on fixed parameter models and cannot track dynamic changes in the system in real time. Summary of the Invention

[0005] The embodiments of the present application provide a method, device, electronic device, and storage medium for detecting insulation impedance of an energy storage system, so as to realize dynamic detection of insulation impedance of an energy storage system.

[0006] The embodiments of this application adopt the following technical solutions:

[0007] In a first aspect, an embodiment of the present application provides a method for detecting insulation impedance of an energy storage system, wherein the detection method includes:

[0008] According to the dynamic compensation current unit, an adjustable constant current source structure and a capacitor compensation circuit are adopted to realize dynamic compensation of current in the energy storage system;

[0009] According to the multi-band signal injection unit, a frequency sweep circuit is used to implement frequency sweep; and

[0010] According to the cooperative control unit, the dynamic compensation current unit and the multi-band signal injection unit are cooperatively controlled to realize insulation impedance detection.

[0011] In some embodiments, the dynamic compensation current unit is further used to

[0012] Drive the power amplifier layer based on the DAC output reference voltage to generate accurate compensation current to be injected into the total positive / total negative electrode of the battery;

[0013] Based on the CL network, the Y capacitor reactance is offset in real time, and the adjustable capacitor value and the adjustable inductor core position are adjusted through FPGA;

[0014] The shunt resistor voltage is collected based on the Σ-Δ ADC and fed back to the DAC control layer to correct the output, forming a high-precision closed-loop control.

[0015] In some embodiments, the adjustable constant current source structure includes:

[0016] DAC control layer, used to use DAC, FPGA generates reference voltage V to the DAC through SPI interface ref ;

[0017] The power amplifier layer includes an operational amplifier differential amplifier circuit and a GaN MOSFET power output circuit. The operational amplifier differential amplifier circuit uses a low-noise operational amplifier to convert the V output of the DAC into a ref The feedback voltage V feedback Perform differential amplification;

[0018] The feedback sampling layer includes a shunt resistor voltage sampling circuit, a Σ-ΔADC digitization circuit, an FPGA error correction circuit, and a DAC output dynamic adjustment circuit.

[0019] In some embodiments, the capacitance compensation circuit includes: Y capacitor interference detection, FPGA parameter calculation, and a dynamic resonant CL network.

[0020] The Y capacitor interference detection is used to measure the battery-to-ground voltage V during the sweep signal injection period. bat-GND , calculate the equivalent capacitance of Y capacitor;

[0021] The FPGA parameter calculation is used to calculate the required compensation inductance L according to the current sweep frequency f and CY value;

[0022] The dynamic resonant CL network is used to accurately adjust the inductance value to the calculated value.

[0023] In some embodiments, the multi-band signal injection unit includes:

[0024] A DDS frequency sweep signal generating circuit, used for generating a DDS frequency sweep signal;

[0025] A DC bias superposition circuit, used to superimpose the DDS frequency sweep signal onto the target DC bias;

[0026] Common mode choke and RC low-pass filter circuits are used to enhance anti-interference.

[0027] In some embodiments, according to a collaborative control unit, collaborative control of the dynamic compensation current unit and the multi-band signal injection unit is adopted to implement insulation impedance detection, including:

[0028] The multi-band signal injection unit outputs a frequency sweep signal injection loop, uses a coupling capacitor C to block the DC bias voltage and only allows the frequency sweep AC signal to pass through, and then is directly connected to the battery after output;

[0029] The dynamic compensation current unit outputs the dynamic compensation current and is grounded through the CL resonant network to form a parallel path with the sweep frequency signal.

[0030] In some embodiments, the insulation impedance detection includes:

[0031] Initialization stage: configuring sweep frequency parameters and calibrating the zero point of the dynamic compensation current unit;

[0032] Low-frequency sweep stage; sweep compensation on and off to calculate the initial resistance Rx and capacitance Cx;

[0033] During the dynamic compensation startup phase, turn on the compensation sweep and adjust the capacitor Cx;

[0034] During the high-frequency sweep phase, both sweep and compensation are turned on, and high-frequency data is collected to calculate the final resistance Rx and capacitance Cx.

[0035] In a second aspect, an embodiment of the present application further provides an energy storage system insulation impedance detection device, wherein the detection device includes:

[0036] A dynamic compensation module is used to implement dynamic compensation of current in the energy storage system using an adjustable constant current source structure and a capacitor compensation circuit based on a dynamic compensation current unit;

[0037] A frequency sweep module, configured to implement frequency sweeping by using a frequency sweep circuit according to the multi-band signal injection unit; and

[0038] The collaborative control module is used to realize insulation impedance detection by adopting the collaborative control of the dynamic compensation current unit and the multi-band signal injection unit according to the collaborative control unit.

[0039] In a third aspect, an embodiment of the present application further provides an electronic device, comprising: a processor; and a memory arranged to store computer-executable instructions, wherein the executable instructions, when executed, enable the processor to perform the above method.

[0040] In a fourth aspect, an embodiment of the present application further provides a computer-readable storage medium, which stores one or more programs. When the one or more programs are executed by an electronic device including multiple application programs, the electronic device executes the above method.

[0041] At least one of the above technical solutions adopted in the embodiments of the present application can achieve the following beneficial effects: according to the dynamic compensation current unit, an adjustable constant current source structure and a capacitor compensation circuit are adopted to realize dynamic compensation of the current in the energy storage system. And according to the multi-band signal injection unit, a sweeping circuit is adopted to realize sweeping. Finally, according to the collaborative control unit, the dynamic compensation current unit and the multi-band signal injection unit are collaboratively controlled to realize insulation impedance detection. Through the above method, the energy storage system insulation impedance collaborative detection based on dynamic DC injection and capacitor compensation not only combines sweeping technology with dynamic current compensation to solve Y capacitor interference, but also solves the signal crosstalk problem through collaborative control. At the same time, the dynamic compensation current module uses hardware-level closed-loop control and dynamic vibration tuning design to achieve real-time adaptation, effectively improving the compensation accuracy. Then, through hardware-level collaborative control and adaptive parameter optimization, the efficient integration of multi-band signal injection and dynamic compensation current modules is realized, solving the problems of poor signal integrity and low compensation accuracy in insulation detection of energy storage systems, and isolating sweeping and compensation through time-sharing multiplexing strategy to solve the signal crosstalk problem, and finally outputting high-precision insulation detection results. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0043] Figure 1 This is a system framework diagram of the insulation impedance detection device in an embodiment of the present application;

[0044] Figure 2 Schematic diagram of the flow of the insulation impedance detection method of the energy storage system in the embodiment of the present application;

[0045] Figure 3 This is a schematic diagram of the design architecture of an adjustable constant current source in an embodiment of the present application;

[0046] Figure 4 This is a schematic diagram of the capacitance compensation circuit design in an embodiment of the present application;

[0047] Figure 5 This is a schematic diagram of the overall framework of the dynamic compensation module in the embodiment of the present application;

[0048] Figure 6 Schematic diagram of the topology framework of the frequency sweeping circuit of the multi-band signal injection unit in an embodiment of the present application;

[0049] Figure 7 Schematic diagram of a coupling circuit for signal injection and compensation in an embodiment of the present application;

[0050] Figure 8 This is a schematic diagram of the timing control logic in the embodiment of the present application;

[0051] Figure 9 This is a schematic diagram of the collaborative working process between the signal injection unit and the dynamic compensation current module in an embodiment of the present application;

[0052] Figure 10 This is a structural diagram of an insulation impedance detection device for an energy storage system in an embodiment of the present application;

[0053] Figure 11 This is a schematic structural diagram of an electronic device in an embodiment of the present application. DETAILED DESCRIPTION

[0054] To make the purpose, technical solutions, and advantages of this application more clear, the technical solutions of this application will be clearly and completely described below in conjunction with the specific embodiments of this application and the corresponding drawings. Obviously, the embodiments described are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0055] The technical solutions provided by the embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0056] like Figure 1The figure shows the system framework diagram of the insulation impedance detection device, which includes a dynamic compensation current module, a multi-band signal injection unit, and a collaborative control module. The dynamic compensation current module includes an adjustable constant current source and a capacitance compensation circuit. Specifically, the dynamic compensation current module adopts an adjustable constant current source design structure, which includes a DAC control layer, a power amplification layer, and a feedback sampling layer. The feedback sampling layer realizes high-precision closed-loop control. The dynamic compensation current module also adopts a capacitance compensation circuit design, which adopts a dynamic vibration tuning design to achieve real-time adaptation and improve the accuracy of capacitance compensation. The DDS frequency sweep signal in the multi-band signal injection unit realizes 0.1Hz-10kHz dynamic frequency sweep and adaptive switching of charge and discharge conditions. The DC bias in the multi-band signal injection unit is superimposed, and the battery polarization damage is avoided by superimposing a ±5V low-voltage DC bias. The frequency sweep unit in the multi-band signal injection unit has an anti-interference design. The collaborative control module solves the signal crosstalk problem through a time-sharing multiplexing strategy by collaboratively controlling the signal injection unit and the dynamic compensation current module.

[0057] The present application embodiment provides a method for detecting insulation impedance of an energy storage system, such as Figure 2 As shown, a flow chart of a method for detecting insulation impedance of an energy storage system according to an embodiment of the present application is provided. The method includes at least the following steps S210 to S230:

[0058] In step S210 , an adjustable constant current source structure and a capacitor compensation circuit are used according to the dynamic compensation current unit to achieve dynamic compensation of the current in the energy storage system.

[0059] The dynamic compensation current unit utilizes an adjustable constant current source structure and a capacitor compensation circuit to achieve dynamic current compensation in the energy storage system. Specifically, hardware-level closed-loop control of the dynamic compensation current module is used, with Σ-Δ ADC feedback and FPGA real-time correction effectively improving compensation accuracy.

[0060] In step S220 , a frequency sweep circuit is used according to the multi-band signal injection unit to implement frequency sweep.

[0061] The multi-band signal injection unit solves the signal injection problem in insulation detection of energy storage systems by adopting dynamic frequency sweeping to cover all working conditions, low-voltage DC bias protection battery and anti-interference design technology.

[0062] In addition, by adopting a time-division multiplexing strategy to isolate frequency sweeping and compensation, the signal crosstalk problem is solved, and finally high-precision insulation detection results are output.

[0063] In step S230 , according to the cooperative control unit, cooperative control of the dynamic compensation current unit and the multi-band signal injection unit is adopted to implement insulation impedance detection.

[0064] Combining frequency sweeping technology with dynamic current compensation addresses Y-capacitor interference, enables insulation impedance detection, and solves signal crosstalk issues through collaborative control. The collaborative control unit achieves efficient integration of multi-band signal injection and dynamic compensation current modules through hardware-level collaborative control and adaptive parameter optimization, resolving the issues of poor signal integrity and low compensation accuracy in insulation detection of energy storage systems.

[0065] Through the above method, the insulation impedance collaborative detection of the energy storage system based on dynamic DC injection and capacitor compensation is achieved: (1) the frequency sweeping technology is combined with dynamic current compensation to solve the Y capacitor interference, and the signal crosstalk problem is solved through collaborative control; (2) the hardware-level closed-loop control of the dynamic compensation current module is used, and the compensation accuracy is effectively improved through Σ-ΔADC feedback + FPGA real-time correction; (3) the dynamic vibration tuning design is adopted to achieve real-time self-adaptation and adapt to any Y capacitor value.

[0066] Unlike related technologies, where the Y-capacitors on the DC side of the energy storage converter PCS form a high-frequency charge-discharge loop during bridge testing, causing the test signal to be shunted and misinterpreted as low insulation impedance. This method, utilizing dynamic frequency sweeps to cover all operating conditions, low-voltage DC bias protection for the battery, and anti-interference design, addresses the signal injection challenge in insulation testing of energy storage systems.

[0067] Unlike related technologies, where the Y-capacitor on the mains side is coupled with the battery system, exacerbating the high-frequency harmonic penetration effect and causing insulation resistance detection errors to exceed 50%. This design, through hardware-level collaborative control and adaptive parameter optimization, achieves efficient integration of multi-band signal injection and dynamic compensation current modules, resolving the issues of poor signal integrity and low compensation accuracy in insulation detection of energy storage systems.

[0068] Unlike related technologies, in hybrid energy systems, the frequency bands of carrier communication signals and insulation detection signals from different devices overlap, causing crosstalk. This method combines frequency sweeping technology with dynamic current compensation to address Y-capacitor interference and resolve signal crosstalk through coordinated control.

[0069] Unlike related technologies, where existing detection algorithms rely on fixed parameter models and are unable to track dynamic system changes in real time, the above method uses hardware-level closed-loop control of the dynamic compensation current module, with Σ-Δ ADC feedback and FPGA real-time correction, effectively improving compensation accuracy. This solution also employs a dynamic vibration tuning design to achieve real-time self-adaptation and adapt to any Y-capacitor value.

[0070] In one embodiment of the present application, the dynamic compensation current unit is also used to drive the power amplifier layer based on the DAC output reference voltage to generate precise compensation current to be injected into the total positive / total negative pole of the battery; based on the CL network, the Y capacitor reactance is offset in real time, and the adjustable capacitor capacitance value and the adjustable inductor core position are adjusted through the FPGA; based on the Σ-ΔADC, the shunt resistor voltage is collected and fed back to the DAC control layer to correct the output, forming a high-precision closed-loop control.

[0071] like Figure 3 As shown in the figure, the design architecture of the adjustable constant current source includes a DAC control layer, a power amplification layer, and a feedback sampling layer.

[0072] In one embodiment of the present application, the adjustable constant current source structure includes: a DAC control layer for using a DAC, and an FPGA generates a reference voltage V to the DAC through an SPI interface. ref ; Power amplifier layer, including an operational amplifier differential amplifier circuit and a GaN MOSFET power output circuit, the operational amplifier differential amplifier circuit, by using a low-noise operational amplifier to output the V ref The feedback voltage V feedback Perform differential amplification; feedback sampling layer, including shunt resistor voltage sampling circuit, Σ-ΔADC digitization circuit, FPGA error correction circuit, DAC output dynamic adjustment circuit.

[0073] The DAC control layer uses a 24-bit high-precision DAC. The FPGA generates an accurate reference voltage Vref to the 24-bit DAC through the SPI interface, supporting dynamic voltage adjustment to adapt to different working conditions. For example, if a +1mA compensation current is required and the feedback sampling resistor Rshunt is set to 0.01Ω, the DAC reference voltage Vref is:

[0074] V ref =I out ×R shunt =1mA×0.01Ω=10μV

[0075] The power amplifier layer is composed of a closed-loop circuit consisting of an operational amplifier differential amplifier link and a GaN MOSFET power output link. The operational amplifier differential amplifier link uses a low-noise operational amplifier to convert the V output of the DAC into a ref The feedback voltage V feedback For differential amplification, the gain coefficient G is:

[0076] G=1+R f / R in

[0077] Where Rf is the feedback resistor and Rin is the output resistor.

[0078] Output error voltage V error for:

[0079] V error =(V ref -V feedback )×G

[0080] Output error voltage V error Used to drive the GaN MOSFET gate.

[0081] It can be understood that GaN MOSFET is a semiconductor device based on gallium nitride material, which has the characteristics of high efficiency, low switching loss and low conduction loss. In the embodiment of the present application, GaN MOSFET is used to effectively improve the response speed. Under the drive of Verror, the output current I comp , due to closed-loop control, V feedback Real-time approximation of V ref , finally I comp for:

[0082] I comp ≈V ref / R shunt .

[0083] like Figure 5 As shown, the feedback sampling layer includes shunt resistor voltage sampling, Σ-Δ ADC digitization, FPGA error correction, and DAC output dynamic adjustment. The specific closed-loop calibration process is as follows:

[0084] Step 1: First, the voltage V across the shunt resistor shunt =I comp ×R shunt , after being amplified by the differential amplifier, it is input into the ADC;

[0085] Step 2: Filter the sampled AD value to suppress high-frequency noise and output a 24-bit digital value D ADC

[0086] Step 3: Calculate the actual current value I comp (real),

[0087] I comp (real)=[D ADC ×V ref (ADC)] / [2 24 ×R shunt ×G amp ]

[0088] Where V ref (ADC) takes 24-bit high-precision DAC reference voltage range 0-5V; 2 24 Corresponding to 24-bit ADC resolution; Gamp is the gain of the amplifier, which can be 100;

[0089] Step 4: FPGA Comparison I comp (real) and target value I comp (target), generating an error signal ΔI=I target -I real ;

[0090] Step 5: Calculate the DAC correction value ΔV using the PID algorithm DAC

[0091] ΔVDAC=Kp·ΔI+Ki·∑ΔI+Kd·[d(ΔI) / dt]

[0092] Among them, K, Ki, and Kd are optimized based on the measured dynamic response;

[0093] Step 6: FPGA updates the DAC output value

[0094] D DAC (new)=D DAC (old)+ΔV DAC / V ref .

[0095] In one embodiment of the present application, the capacitance compensation circuit includes: Y capacitor interference detection, FPGA parameter calculation, and dynamic resonant CL network. The Y capacitor interference detection is used to measure the battery-to-ground voltage V during the sweep signal injection period. bat-GND , calculate the equivalent capacitance of the Y capacitor; the FPGA parameter calculation is used to calculate the required compensation inductor L according to the current sweep frequency f and CY value; the dynamic resonant CL network is used to accurately adjust the inductance value to the calculated value.

[0096] like Figure 4 The figure below shows the capacitor compensation circuit design, where the dynamic tuning signal path includes Y capacitor interference detection, FPGA parameter calculation, and dynamic resonant CL network. The specific resonance cancellation process is as follows:

[0097] Step S1, Y capacitor interference monitoring, during the sweep signal injection period, measure the battery-to-ground voltage V bat-GND , through the formula CY=Icomp / [2πf·V bat-GND ], calculate the equivalent capacitance of the Y capacitor.

[0098] Step S2, FPGA dynamically calculates the resonance parameters, FPGA calculates the resonance parameters according to the current sweep frequency f and C Y value, calculate the required compensation inductance L

[0099] L=1 / [(2πf)2(C comp+C Y )]

[0100] Among them C comp is the current value of the digital capacitor array;

[0101] Step S3, CL network tuning, first through I 2 The C interface controls the capacitor array, increasing or decreasing C in a certain step size. comp , offset C Y Then, by adjusting the core position of the adjustable inductor, the inductance value is accurately adjusted to the calculated value;

[0102] Step S4, re-measure V bat-GND If the voltage drops to the noise level (e.g. <1mV), it indicates that the Y capacitor interference has been offset.

[0103] In one embodiment of the present application, the multi-band signal injection unit includes: a DDS sweep signal generation circuit for generating a DDS sweep signal; a DC bias superposition circuit for superimposing the DDS sweep signal on the target DC bias; a common-mode choke and an RC low-pass filter circuit for enhancing anti-interference.

[0104] like Figure 6 The figure shows the topological framework of the frequency sweep circuit of the multi-band signal injection unit, which includes a DDS frequency sweep signal generation module, a DC bias superposition circuit, a common-mode choke, and an RC low-pass filter.

[0105] The DDS frequency sweep signal generation module includes a clock circuit, frequency sweep configuration, frequency sweep mode, and output conditioning.

[0106] The clock circuit

[0107] The main component of the clock circuit is the crystal oscillator, which is responsible for generating a stable clock beat. A higher system clock allows the DDS chip to output a wider range of frequencies while improving the frequency resolution. The frequency sweep configuration is equivalent to telling the chip what frequency to output at the moment. The frequency control word FTW is calculated as follows:

[0108] FTW=[f out / f sys_clk ]×2 N

[0109] where f out is the frequency to be output, f sys_clkThe current system clock is N, and the current resolution is N. The frequency sweep mode uses two modes: linear sweep and burst mode. The linear sweep has a dwell time of 50ms per frequency point. 50ms allows sufficient time for the device under test to respond stably and prevent signal fluctuations from affecting accuracy. The sweep interval ranges from 0.1Hz (low frequency band) to 100Hz (high frequency band). Burst mode triggers intensive sampling in the 10kHz high frequency band only during charge and discharge transients. Intensive sampling in the high frequency band can capture rapidly changing dynamic characteristics.

[0110] Output conditioning primarily stabilizes the signal and filters out noise. Differential output is used, as differential signals are inherently resistant to interference and are suitable for long-distance transmission or in high-noise environments. The DC bias superposition circuit superimposes the swept frequency signal onto a ±5V DC bias to avoid battery polarization effects. A common-mode choke and RC low-pass filter enhance interference resistance. The common-mode choke is connected in series with the signal output to suppress common-mode noise, while the RC low-pass filter suppresses high-frequency noise.

[0111] In one embodiment of the present application, according to a collaborative control unit, collaborative control of the dynamic compensation current unit and the multi-band signal injection unit is adopted to realize insulation impedance detection, including: the multi-band signal injection unit outputs a sweep signal injection loop, uses a coupling capacitor C to block the DC bias voltage and only allows the sweep AC signal to pass through, and is directly connected to the battery after output; the dynamic compensation current unit outputs the dynamic compensation current and is grounded through the CL resonant network to form a parallel path with the sweep signal.

[0112] like Figure 7 The figure shows the coupling circuit for signal injection and compensation. Coupling capacitor C blocks the DC bias voltage, allowing only the swept-frequency AC signal to pass. The swept-frequency signal is directly connected to the battery's positive (or negative) terminal and shares the same injection loop with the dynamic compensation current. The dynamic compensation current path is connected to ground through the CL resonant network, forming a parallel path with the swept-frequency signal.

[0113] In one embodiment of the present application, the insulation impedance detection includes: an initialization stage; configuring the sweep frequency parameters and calibrating the zero point of the dynamic compensation current unit; a low-frequency sweep frequency stage; sweep frequency to turn on and off compensation, and solve the initial resistance Rx and capacitance Cx; a dynamic compensation startup stage, turning on and off the compensation sweep frequency, and adjusting the capacitance Cx; a high-frequency sweep frequency stage, turning on both the sweep frequency and compensation, and collecting high-frequency data to solve the final resistance Rx and capacitance Cx.

[0114] like Figure 8 The following is the timing control logic:

[0115] Step 1: Phase 1 (0-50ms), inject a 0.1Hz-1kHz sweep signal, turn off the dynamic compensation module, and collect the low-frequency impedance response.

[0116] Step 2: Phase 2 (50-100ms), start the dynamic compensation module, calculate the Y capacitor parameters based on the low-frequency data, and adjust the CL network.

[0117] Step 3: Phase 3 (100-150ms), inject a 1kHz-10kHz sweep signal, turn on the compensation module, and collect high-frequency capacitive reactance data.

[0118] The FPGA outputs synchronization signals through GPIO to control the enable / disable timing of the two modules and solve the signal crosstalk problem.

[0119] like Figure 9 The figure shows the collaborative workflow of the signal injection unit and the dynamic compensation current module. The steps are as follows:

[0120] Step 1: Initialization stage, configure the frequency sweep parameters and calibrate the zero point of the dynamic compensation module;

[0121] Step 2: Sweep the low frequency band, turn on the sweep, turn off compensation, and calculate the initial Rx and Cx;

[0122] Step 3: Start dynamic compensation, turn on compensation, turn off frequency sweep, and adjust Cx;

[0123] Step 4: Sweep the high frequency band, turn on both sweep and compensation, collect high frequency data, and calculate the final Rx and Cx.

[0124] Through the above method, the collaborative detection method and device of insulation impedance of energy storage system based on dynamic DC injection and capacitor compensation combines sweep frequency technology with dynamic current compensation for the first time to solve Y capacitor interference and solve signal crosstalk problem through collaborative control. At the same time, the dynamic compensation current module uses hardware-level closed-loop control and dynamic vibration tuning design to achieve real-time adaptation, effectively improving the compensation accuracy.

[0125] In addition, through hardware-level collaborative control and adaptive parameter optimization, efficient integration of multi-band signal injection and dynamic compensation current modules is achieved, solving the problems of poor signal integrity and low compensation accuracy in insulation detection of energy storage systems. The time-sharing multiplexing strategy is used to isolate frequency scanning and compensation, solve the signal crosstalk problem, and ultimately output high-precision insulation detection results.

[0126] The embodiment of the present application also provides an energy storage system insulation impedance detection device 1000, such as Figure 10 As shown, a schematic structural diagram of an energy storage system insulation impedance detection device in an embodiment of the present application is provided. The energy storage system insulation impedance detection device 1000 includes at least: a dynamic compensation module 1010, a frequency sweep module 1020, and a second collaborative control module 1030, wherein:

[0127] In one embodiment of the present application, the dynamic compensation module 1010 is specifically configured to: implement dynamic compensation of current in the energy storage system by using an adjustable constant current source structure and a capacitor compensation circuit according to a dynamic compensation current unit.

[0128] The dynamic compensation current unit utilizes an adjustable constant current source structure and a capacitor compensation circuit to achieve dynamic current compensation in the energy storage system. Specifically, hardware-level closed-loop control of the dynamic compensation current module is used, with Σ-Δ ADC feedback and FPGA real-time correction effectively improving compensation accuracy.

[0129] In one embodiment of the present application, the frequency sweep module 1020 is specifically configured to: implement frequency sweeping by using a frequency sweep circuit according to the multi-band signal injection unit.

[0130] The multi-band signal injection unit solves the signal injection problem in insulation detection of energy storage systems by adopting dynamic frequency sweeping to cover all working conditions, low-voltage DC bias protection battery and anti-interference design technology.

[0131] In addition, by adopting a time-division multiplexing strategy to isolate frequency sweeping and compensation, the signal crosstalk problem is solved, and finally high-precision insulation detection results are output.

[0132] In one embodiment of the present application, the second collaborative control module 1030 is specifically configured to: according to a collaborative control unit, adopt collaborative control of the dynamic compensation current unit and the multi-band signal injection unit to implement insulation impedance detection.

[0133] Combining frequency sweeping technology with dynamic current compensation addresses Y-capacitor interference, enables insulation impedance detection, and solves signal crosstalk issues through collaborative control. The collaborative control unit achieves efficient integration of multi-band signal injection and dynamic compensation current modules through hardware-level collaborative control and adaptive parameter optimization, resolving the issues of poor signal integrity and low compensation accuracy in insulation detection of energy storage systems.

[0134] In one embodiment of the present application, the dynamic compensation module 1010 is further configured to

[0135] Drive the power amplifier layer based on the DAC output reference voltage to generate accurate compensation current to be injected into the total positive / total negative electrode of the battery;

[0136] Based on the CL network, the Y capacitor reactance is offset in real time, and the adjustable capacitor value and the adjustable inductor core position are adjusted through FPGA;

[0137] The shunt resistor voltage is collected based on the Σ-Δ ADC and fed back to the DAC control layer to correct the output, forming a high-precision closed-loop control.

[0138] In one embodiment of the present application, the dynamic compensation module 1010 is further configured to:

[0139] DAC control layer, used to use DAC, FPGA generates reference voltage V to the DAC through SPI interface ref ;

[0140] The power amplifier layer includes an operational amplifier differential amplifier circuit and a GaN MOSFET power output circuit. The operational amplifier differential amplifier circuit uses a low-noise operational amplifier to convert the V output of the DAC into a ref The feedback voltage V feedback Perform differential amplification;

[0141] The feedback sampling layer includes a shunt resistor voltage sampling circuit, a Σ-ΔADC digitization circuit, an FPGA error correction circuit, and a DAC output dynamic adjustment circuit.

[0142] In one embodiment of the present application, the dynamic compensation module 1010 is further configured to include: Y capacitor interference detection, FPGA parameter calculation, dynamic resonant CL network,

[0143] The Y capacitor interference detection is used to measure the battery-to-ground voltage V during the sweep signal injection period. bat-GND , calculate the equivalent capacitance of Y capacitor;

[0144] The FPGA parameter calculation is used to calculate the required compensation inductance L according to the current sweep frequency f and CY value;

[0145] The dynamic resonant CL network is used to accurately adjust the inductance value to the calculated value.

[0146] In one embodiment of the present application, the dynamic compensation module 1010 is further configured to:

[0147] A DDS frequency sweep signal generating circuit, used for generating a DDS frequency sweep signal;

[0148] A DC bias superposition circuit, used to superimpose the DDS frequency sweep signal onto the target DC bias;

[0149] Common mode choke and RC low-pass filter circuits are used to enhance anti-interference.

[0150] In one embodiment of the present application, the collaborative control module 1003 is further configured to:

[0151] The multi-band signal injection unit outputs a frequency sweep signal injection loop, uses a coupling capacitor C to block the DC bias voltage and only allows the frequency sweep AC signal to pass through, and then is directly connected to the battery after output;

[0152] The dynamic compensation current unit outputs the dynamic compensation current and is grounded through the CL resonant network to form a parallel path with the sweep frequency signal.

[0153] In one embodiment of the present application, the collaborative control module 1003 is further configured to:

[0154] Initialization stage: configuring sweep frequency parameters and calibrating the zero point of the dynamic compensation current unit;

[0155] Low-frequency sweep stage; sweep compensation on and off to calculate the initial resistance Rx and capacitance Cx;

[0156] During the dynamic compensation startup phase, turn on the compensation sweep and adjust the capacitor Cx;

[0157] During the high-frequency sweep phase, both sweep and compensation are turned on, and high-frequency data is collected to calculate the final resistance Rx and capacitance Cx.

[0158] It can be understood that the above-mentioned energy storage system insulation impedance detection device can implement each step of the energy storage system insulation impedance detection method provided in the aforementioned embodiment. The relevant explanations about the energy storage system insulation impedance detection method are applicable to the energy storage system insulation impedance detection device and will not be repeated here.

[0159] Figure 11 This is a schematic diagram of the structure of an electronic device according to an embodiment of the present application. Figure 11 At the hardware level, the electronic device includes a processor and, optionally, an internal bus, a network interface, and memory. The memory may include internal memory, such as high-speed random-access memory (RAM), or non-volatile memory, such as at least one disk drive. Of course, the electronic device may also include other hardware required for its services.

[0160] The processor, network interface, and memory can be interconnected via an internal bus, which can be an ISA (Industry Standard Architecture) bus, a PCI (Peripheral Component Interconnect) bus, or an EISA (Extended Industry Standard Architecture) bus. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 11 Only one bidirectional arrow is used in the diagram, but this does not mean that there is only one bus or one type of bus.

[0161] The memory is used to store programs. Specifically, the program may include program code, which includes computer operating instructions. The memory may include internal memory and non-volatile memory, and provides instructions and data to the processor.

[0162] The processor reads the corresponding computer program from the non-volatile memory into the internal memory and then runs it, forming an energy storage system insulation impedance detection device at the logical level. The processor executes the program stored in the memory and is specifically used to perform the following operations:

[0163] According to the dynamic compensation current unit, an adjustable constant current source structure and a capacitor compensation circuit are adopted to realize dynamic compensation of current in the energy storage system;

[0164] According to the multi-band signal injection unit, a frequency sweep circuit is used to implement frequency sweep; and

[0165] According to the cooperative control unit, the dynamic compensation current unit and the multi-band signal injection unit are cooperatively controlled to realize insulation impedance detection.

[0166] The above application Figure 2The method performed by the energy storage system insulation impedance detection device disclosed in the illustrated embodiment can be applied to a processor or implemented by a processor. The processor may be an integrated circuit chip with signal processing capabilities. During implementation, each step of the above method can be completed by hardware integrated logic circuits in the processor or by software instructions. The above processor can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. The various methods, steps, and logic block diagrams disclosed in the embodiments of this application can be implemented or executed. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in the embodiments of this application can be directly implemented and executed by a hardware decoding processor, or by a combination of hardware and software modules in the decoding processor. The software module can be located in a storage medium well-known in the art, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, etc. The storage medium is located in the memory, and the processor reads the information in the memory and, in conjunction with its hardware, completes the steps of the above method.

[0167] The electronic device may also perform Figure 2 The method of the energy storage system insulation impedance detection device is implemented, and the energy storage system insulation impedance detection device is implemented in Figure 2 The functions of the illustrated embodiment will not be described in detail in the embodiments of the present application.

[0168] The embodiment of the present application also provides a computer-readable storage medium, which stores one or more programs, wherein the one or more programs include instructions, which, when executed by an electronic device including multiple application programs, can enable the electronic device to execute Figure 2 The method performed by the energy storage system insulation impedance detection device in the illustrated embodiment is specifically used to perform:

[0169] According to the dynamic compensation current unit, an adjustable constant current source structure and a capacitor compensation circuit are adopted to realize dynamic compensation of current in the energy storage system;

[0170] According to the multi-band signal injection unit, a frequency sweep circuit is used to implement frequency sweep; and

[0171] According to the cooperative control unit, the dynamic compensation current unit and the multi-band signal injection unit are cooperatively controlled to realize insulation impedance detection.

[0172] It will be understood by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0173] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts and / or block diagrams. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0174] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0175] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0176] In a typical configuration, a computing device includes one or more processors (CPUs), input / output interfaces, network interfaces, and memory.

[0177] Memory may include non-permanent storage in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. Memory is an example of a computer-readable medium.

[0178] Computer-readable media includes permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. The information can be computer-readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable media does not include transitory computer-readable media (transitory media), such as modulated data signals and carrier waves.

[0179] It should also be noted that the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, commodity, or apparatus that includes a series of elements includes not only those elements but also other elements not explicitly listed, or includes elements inherent to such process, method, commodity, or apparatus. In the absence of further limitations, an element defined by the phrase "comprises a ..." does not exclude the presence of other identical elements in the process, method, commodity, or apparatus that includes the element.

[0180] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present application may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0181] The foregoing is merely an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should all be included within the scope of the claims of the present application.

Claims

1. A method for detecting insulation impedance of an energy storage system, wherein: The detection method comprises: According to the dynamic compensation current unit, an adjustable constant current source structure and a capacitor compensation circuit are adopted to realize dynamic compensation of current in the energy storage system; According to the multi-band signal injection unit, a frequency sweep circuit is used to implement frequency sweep; and According to the cooperative control unit, the dynamic compensation current unit and the multi-band signal injection unit are cooperatively controlled to realize insulation impedance detection.

2. The method according to claim 1, wherein: The dynamic compensation current unit is also used to Drive the power amplifier layer based on the DAC output reference voltage to generate accurate compensation current to be injected into the total positive / total negative electrode of the battery; Based on the CL network, the Y capacitor reactance is offset in real time, and the adjustable capacitor value and the adjustable inductor core position are adjusted through FPGA; The shunt resistor voltage is collected based on the Σ-Δ ADC and fed back to the DAC control layer to correct the output, forming a high-precision closed-loop control.

3. The method according to claim 1, wherein: The adjustable constant current source structure comprises: DAC control layer, used to use DAC, FPGA generates reference voltage V to the DAC through SPI interface ref ; The power amplifier layer includes an operational amplifier differential amplifier circuit and a GaN MOSFET power output circuit. The operational amplifier differential amplifier circuit uses a low-noise operational amplifier to convert the V output of the DAC into a ref The feedback voltage V feedback Perform differential amplification; The feedback sampling layer includes a shunt resistor voltage sampling circuit, a Σ-ΔADC digitization circuit, an FPGA error correction circuit, and a DAC output dynamic adjustment circuit.

4. The method according to claim 1, wherein: The capacitance compensation circuit includes: Y capacitor interference detection, FPGA parameter calculation, dynamic resonant CL network, The Y capacitor interference detection is used to measure the battery-to-ground voltage V during the sweep signal injection period. bat-GND , calculate the equivalent capacitance of Y capacitor; The FPGA parameter calculation is used to calculate the required compensation inductance L according to the current sweep frequency f and CY value; The dynamic resonant CL network is used to accurately adjust the inductance value to the calculated value.

5. The method according to claim 1, wherein: The multi-band signal injection unit includes: A DDS frequency sweep signal generating circuit, used for generating a DDS frequency sweep signal; A DC bias superposition circuit, used to superimpose the DDS frequency sweep signal onto the target DC bias; Common mode choke and RC low-pass filter circuits are used to enhance anti-interference.

6. The method of claim 1, wherein: According to the collaborative control unit, the dynamic compensation current unit and the multi-band signal injection unit are collaboratively controlled to implement insulation impedance detection, including: The multi-band signal injection unit outputs a frequency sweep signal injection loop, uses a coupling capacitor C to block the DC bias voltage and only allows the frequency sweep AC signal to pass through, and then is directly connected to the battery after output; The dynamic compensation current unit outputs the dynamic compensation current and is grounded through the CL resonant network to form a parallel path with the sweep frequency signal.

7. The method of claim 1, wherein: The insulation impedance detection includes: Initialization stage: configuring sweep frequency parameters and calibrating the zero point of the dynamic compensation current unit; Low-frequency sweep stage; sweep compensation on and off to calculate the initial resistance Rx and capacitance Cx; During the dynamic compensation startup phase, turn on the compensation sweep and adjust the capacitor Cx; During the high-frequency sweep phase, both sweep and compensation are turned on, and high-frequency data is collected to calculate the final resistance Rx and capacitance Cx.

8. An energy storage system insulation impedance detection device, wherein: The detection device comprises: A dynamic compensation module is used to implement dynamic compensation of current in the energy storage system using an adjustable constant current source structure and a capacitor compensation circuit based on a dynamic compensation current unit; A frequency sweep module, configured to implement frequency sweeping by using a frequency sweep circuit according to the multi-band signal injection unit; and The collaborative control module is used to realize insulation impedance detection by adopting the collaborative control of the dynamic compensation current unit and the multi-band signal injection unit according to the collaborative control unit.

9. An electronic device comprising: processor; as well as A memory arranged to store computer executable instructions, which when executed cause the processor to perform the method of any one of claims 1 to 7.

10. A computer-readable storage medium storing one or more programs, which, when executed by an electronic device including a plurality of application programs, causes the electronic device to execute the method according to any one of claims 1 to 7.

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