Calculation method for dissipated energy of power module of flexible direct current converter valve and related device

Abstract

The invention relates to the technical field of power electronic devices, in particular to a calculation method for dissipated energy of a power module of a flexible direct current converter valve and a related device. The method comprises the following steps: acquiring a bridge arm voltage average value of the flexible DC converter valve and the temperature of an energy release branch; a first time interval and a second time interval are determined according to the bridge arm voltage average value, the temperature of the energy release branch and a monitored system fault signal, active power of the energy release branch in the first time interval is obtained and integrated, and single-time dissipated energy of the energy release branch is obtained; and the active power of the energy release branch in the second time interval is obtained and integrated to obtain the total dissipated energy of the energy release branch, so that the technical problem that the dissipated energy of the energy release branch is difficult to accurately calculate in the prior art is solved, high-precision monitoring of the dissipated energy of the energy release resistor is realized, and the system protection reliability is improved.

Description

Technical Field

[0001] This invention relates to the field of power electronic device technology, and in particular to a method and related apparatus for calculating the energy dissipation of a power module in a flexible DC converter valve. Background Technology

[0002] The flexible DC-DC converter valve is a core component of flexible DC transmission systems, used to convert electrical energy from AC to DC, playing a crucial role in the power system. The flexible DC-DC converter valve contains a power module, the functional unit responsible for energy conversion; its operating status affects the overall performance and reliability of the converter valve. The power module is connected in parallel to a discharge branch, a vital design feature ensuring system safety. When the power module malfunctions, the discharge branch promptly releases excess energy, preventing damage to other components.

[0003] However, existing technologies struggle to accurately calculate the energy dissipated by the energy leakage branch, which complicates system operation, maintenance, and performance evaluation. Summary of the Invention

[0004] This invention provides a method and related apparatus for calculating the energy dissipation of a power module in a flexible DC converter valve, which solves the technical problem that existing technologies struggle to accurately calculate the energy dissipated by the energy leakage branch.

[0005] This invention provides a method for calculating the energy dissipation of a power module in a flexible DC converter valve, comprising:

[0006] Obtain the average value of the bridge arm voltage and the temperature of the discharge branch of the flexible DC converter valve;

[0007] When the average voltage of the bridge arm is greater than the set voltage of the energy dissipation branch and a system fault signal is detected, the current time is acquired and recorded as the first time. When the average voltage of the bridge arm is less than the set voltage of the exit and a system fault recovery signal is detected, the current time is acquired and recorded as the second time. The first time and the second time form a first time interval.

[0008] When the temperature of the energy dissipation branch is greater than a preset temperature threshold and the average voltage of the bridge arm is greater than the applied fixed voltage, the current time is obtained and recorded as the third time; the first time and the third time are combined to form a second time interval.

[0009] The active power of the energy dissipation branch within the first time interval is acquired and integrated to obtain the single energy dissipation of the energy dissipation branch.

[0010] The active power of the energy dissipation branch within the second time interval is acquired and integrated to obtain the total energy dissipation of the energy dissipation branch.

[0011] Optionally, the method further includes:

[0012] An error message is output when the energy dissipated in a single instance exceeds the preset maximum energy consumption, or when the total energy dissipated exceeds the maximum energy consumption.

[0013] Optionally, the method further includes:

[0014] When the temperature of the energy dissipation branch returns to the preset temperature threshold, the total energy dissipation is set to zero.

[0015] Optionally, the energy-dissipating branch includes an energy-dissipating resistor, and a non-contact current collector is installed on the energy-dissipating resistor; the steps for obtaining the active power of the energy-dissipating branch include:

[0016] Receive the current transmitted by the non-contact current collector and obtain the resistance value of the leakage resistor;

[0017] The active power is obtained by multiplying the square of the current by the resistance value.

[0018] Optionally, the non-contact current collector includes a Rogowski coil and an integrator;

[0019] The conductor at the input terminal of the energy-dissipating resistor passes through the center of the Rogowski coil;

[0020] The integrator is connected to the Rogowski coil and is used to convert the differential voltage induced by the Rogowski coil into current.

[0021] In another aspect, the present invention provides a calculation device for the energy dissipation of a power module of a flexible DC converter valve, the device comprising:

[0022] The first acquisition module is used to acquire the average value of the bridge arm voltage and the temperature of the energy dissipation branch of the flexible DC converter valve;

[0023] The first monitoring module is used to acquire and record the current time as the first moment when the average voltage of the bridge arm is greater than the input set voltage of the energy leakage branch and a system fault signal is detected, and to acquire and record the current time as the second moment when the average voltage of the bridge arm is less than the exit set voltage and a system fault recovery signal is detected; and to form a first time interval by combining the first moment and the second moment.

[0024] The second monitoring module is used to acquire and record the current time as the third time when the temperature of the energy leakage branch is greater than a preset temperature threshold and the average voltage of the bridge arm is greater than the applied fixed voltage; and to form a second time interval by combining the first time and the third time.

[0025] The second acquisition module is used to acquire and integrate the active power of the energy dissipation branch within the first time interval to obtain the single dissipation energy of the energy dissipation branch.

[0026] The third acquisition module is used to acquire and integrate the active power of the energy dissipation branch within the second time interval to obtain the total energy dissipation of the energy dissipation branch.

[0027] Optionally, it also includes:

[0028] The output module is used to output an abnormal prompt when the single energy dissipation is greater than the preset maximum energy consumption, or when the total energy dissipation is greater than the maximum energy consumption.

[0029] Optionally, it also includes:

[0030] The zeroing module is used to zero out the total dissipated energy when the temperature of the energy dissipation branch returns to the preset temperature threshold.

[0031] In another aspect, the present invention provides an electronic device, the device comprising a processor and a memory:

[0032] The memory is used to store program code and transmit the program code to the processor;

[0033] The processor is used to execute the method described above according to the instructions in the program code.

[0034] In another aspect, the present invention provides a computer-readable storage medium for storing program code for performing the method described above.

[0035] As can be seen from the above technical solutions, the present invention has the following advantages:

[0036] This invention provides a method for calculating the energy dissipation of a power module in a flexible DC-DC converter valve, including: acquiring the average arm voltage and temperature of the energy dissipation branch of the flexible DC-DC converter valve; when the average arm voltage is greater than the input set voltage of the energy dissipation branch and a system fault signal is detected, acquiring and recording the current time as a first time; when the average arm voltage is less than the exit set voltage and a system fault recovery signal is detected, acquiring and recording the current time as a second time; combining the first time and the second time to form a first time interval; when the temperature of the energy dissipation branch is greater than a preset temperature threshold and the average arm voltage is greater than the input set voltage, acquiring and recording the current time as a third time; combining the first time and the third time to form a second time interval; acquiring and integrating the active power of the energy dissipation branch within the first time interval to obtain the single energy dissipation of the energy dissipation branch; acquiring and integrating the active power of the energy dissipation branch within the second time interval to obtain the total energy dissipation of the energy dissipation branch.

[0037] In this invention, by acquiring the average arm voltage of the flexible DC converter valve and the temperature of the energy dissipation branch, the operating status of the flexible DC converter valve is monitored. When the average arm voltage is greater than the set voltage for the energy dissipation branch and a system fault signal is detected, the current time is acquired and recorded as the first time. When the average arm voltage is less than the set voltage for the exit and a system fault recovery signal is detected, the current time is acquired and recorded as the second time. The first time and the second time constitute a first time interval, which realizes the determination of the time interval for the energy dissipation branch to be engaged and the energy dissipation during a single fault, providing technical support for accurately calculating the single energy dissipation of the energy dissipation branch. When the temperature of the energy dissipation branch is greater than a preset temperature threshold, and When the average voltage of the bridge arm is greater than the set voltage, the current time is recorded as the third time. The first time and the third time are combined to form a second time interval, thus determining the time interval during which the energy dissipation branch is activated for energy dissipation during continuous faults. This provides technical support for accurately calculating the total energy dissipation of the energy dissipation branch during continuous faults. Furthermore, by acquiring and integrating the active power of the energy dissipation branch within the first time interval, the single energy dissipation of the energy dissipation branch is obtained, thus achieving accurate calculation of the single energy dissipation. Similarly, by acquiring and integrating the active power of the energy dissipation branch within the second time interval, the total energy dissipation of the energy dissipation branch is obtained, thus achieving accurate calculation of the total energy dissipation of the energy dissipation branch.

[0038] Based on the above, the method for calculating the energy dissipation of a power module in a flexible DC converter valve provided by the present invention can accurately calculate the energy dissipation of the energy leakage branch within the power module, thus solving the technical problem that the prior art is unable to accurately calculate the energy dissipated by the energy leakage branch. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 A flowchart illustrating the steps of a method for calculating the energy dissipation of a power module in a flexible DC converter valve, as provided in an embodiment of the present invention.

[0041] Figure 2 This is a schematic diagram of the circuit principle of a non-contact current collector provided in an embodiment of the present invention;

[0042] Figure 3 A schematic diagram of the current waveform of the energy dissipation branch provided in an embodiment of the present invention;

[0043] Figure 4 Another step of the calculation method for the energy dissipation of a power module of a flexible DC converter valve provided in an embodiment of the present invention is shown in the flowchart.

[0044] Figure 5 A flowchart illustrating the steps of a method for calculating the energy dissipation of a power module in a flexible DC converter valve, provided as an application example of the present invention;

[0045] Figure 6 This invention provides a structural block diagram of a calculation device for the energy dissipation of a power module in a flexible DC converter valve, as shown in an embodiment of the invention. Detailed Implementation

[0046] Energy dissipation resistors are installed on the energy dissipation branch to dissipate energy. However, in actual operation, it is difficult to accurately measure the current flowing through the energy dissipation resistor and the active power consumed, which brings difficulties to the operation, maintenance, and performance evaluation of the system. For example, the inability to accurately determine whether the energy dissipation resistor is in an appropriate active power operating state may lead to premature damage to the energy dissipation resistor or the inability to effectively dissipate excess energy, thereby affecting the reliability and stability of the flexible DC converter valve. Therefore, developing a method that can accurately calculate the energy dissipated by the energy dissipation resistor is of significant practical importance.

[0047] In view of this, embodiments of the present invention provide a method and related apparatus for calculating the energy dissipation of a power module in a flexible DC converter valve, which is used to solve the technical problem that it is difficult to accurately calculate the energy dissipated by the energy leakage branch.

[0048] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0049] Please see Figure 1 The method for calculating the energy dissipation of a flexible DC converter valve power module provided in this embodiment of the invention includes:

[0050] 101. Obtain the average value of the bridge arm voltage and the temperature of the energy dissipation branch of the flexible DC converter valve.

[0051] It should be noted that the flexible DC converter valve is divided into an upper arm and a lower arm. Each arm has multiple power modules, and the average voltage of the arm is the average of the sum of the voltages of all power modules in both arms. The energy dissipation branch includes an energy dissipation resistor. The temperature of the energy dissipation branch is the same as the temperature of the energy dissipation resistor.

[0052] 102. When the average voltage of the bridge arm is greater than the set voltage of the energy dissipation branch and a system fault signal is detected, the current time is acquired and recorded as the first time. When the average voltage of the bridge arm is less than the set voltage of the exit and a system fault recovery signal is detected, the current time is acquired and recorded as the second time. The first time and the second time are combined to form the first time interval.

[0053] It should be noted that the set voltage for the energy dissipation branch is a preset value, which can be pre-set according to the actual operating conditions. The first moment is when the average bridge arm voltage is greater than the set voltage for the energy dissipation branch and a system fault signal is detected; the second moment is when the average bridge arm voltage is less than the set voltage for deactivation and a system fault recovery signal is detected.

[0054] This embodiment monitors the operating status of the flexible DC-DC converter valve in real time. When the flexible DC-DC converter valve malfunctions, a system fault signal is generated. Therefore, when a system fault signal is detected, it indicates that the flexible DC-DC converter valve has malfunctioned. When a system fault recovery signal is detected, it indicates that the malfunction of the flexible DC-DC converter valve has been resolved and normal operation can be restored. When the average bridge arm voltage is greater than the set voltage for the energy dissipation branch, it indicates that the energy dissipation branch is activated to dissipate energy. When the average bridge arm voltage is less than the set voltage for the energy dissipation branch, it indicates that the energy dissipation branch is deactivated. Therefore, the first time interval indicates the period during which the energy dissipation branch is activated during a single fault. Thus, this step, by monitoring the average bridge arm voltage and the system operating status in real time, determines the period during which the energy dissipation branch is activated during a single fault, providing technical support for accurately calculating the energy dissipated by the energy dissipation branch in a single fault.

[0055] 103. When the temperature of the energy dissipation branch is greater than the preset temperature threshold and the average voltage of the bridge arm is greater than the applied fixed voltage, the current time is obtained and recorded as the third time, and the first time and the third time are combined to form the second time interval.

[0056] It should be noted that the preset temperature threshold refers to the temperature of the discharge resistor under stable operating conditions when the discharge branch is not engaged for a long period of time. The third moment is the moment when the temperature of the discharge branch is greater than the preset temperature threshold and the average voltage of the bridge arm is greater than the set voltage.

[0057] When the temperature of the energy dissipation branch exceeds the preset temperature threshold, and the average voltage of the bridge arm exceeds the set voltage for the energy dissipation branch, it indicates that the energy dissipation branch is activated and the temperature of the energy dissipation resistor gradually rises from its equilibrium state. At this time, the device will issue an alarm signal indicating that the energy dissipation has exceeded the limit. Therefore, the second time interval indicates the period during which the temperature of the energy dissipation resistor gradually rises from its equilibrium state during the activation of the energy dissipation branch.

[0058] Therefore, this step does not monitor system fault signals, but instead determines the time period during which the energy dissipation branch is put into operation for energy dissipation during continuous faults by real-time monitoring of the average bridge arm voltage and the temperature of the energy dissipation branch. This provides technical support for accurately calculating the total energy dissipated by the energy dissipation branch during continuous faults.

[0059] 104. Obtain and integrate the active power of the energy dissipation branch within the first time interval to obtain the single energy dissipation energy of the energy dissipation branch.

[0060] It should be noted that single-time energy dissipation refers to the energy dissipated by the leakage resistor during a single fault.

[0061] This step obtains the active power of the energy dissipation branch within the first time interval and integrates the active power to obtain the single-time dissipation energy of the energy dissipation branch. The calculation principle is as follows:

[0062] The system fault signal is detected and the average voltage of the bridge arm is greater than the set voltage of the energy dissipation branch. The time is recorded as To monitor the system fault recovery signal and ensure that the average bridge arm voltage is less than the exit setpoint voltage of the energy leakage branch. The time is recorded as Then, over a period of time [ Within the first time interval (i.e., the first time interval), the energy E dissipated by the leakage resistor can be obtained by integrating the active power: Thus, the energy dissipated by the leakage resistor during a single fault is obtained.

[0063] In one example, numerical integration can be used to integrate the time interval [ Discretization transforms the integral into a summation calculation: ,in, For discrete time intervals, For discrete time points, The number of discrete time points.

[0064] 105. Obtain and integrate the active power of the energy dissipation branch within the second time interval to obtain the total energy dissipation of the energy dissipation branch.

[0065] It should be noted that the total dissipated energy refers to the total energy dissipated by the leakage resistor during continuous faults. This step obtains the total dissipated energy of the leakage branch by acquiring the active power of the leakage branch within the second time interval and integrating the active power. The calculation principle is as follows:

[0066] When the energy dissipation branch is not engaged for a long period of time, the resistor temperature under steady-state operation is set to T1. This is to monitor that the temperature of the energy dissipation resistor T>T1 and that the average value of the bridge arm voltage is greater than the set voltage for engaging the energy dissipation branch. If the time interval is t3, then the energy Esum dissipated by the leakage resistor during a time interval [t1, t3] (i.e., the second time interval) can be obtained by integrating the active power:

[0067]

[0068] Based on the above, this step yields the total energy dissipation on the leakage resistor during continuous faults.

[0069] It is understandable that the energy dissipation resistor is designed to dissipate all the surplus power at the sending end during the longest fault duration. However, the fault type and duration are uncertain during a single fault, and the active power transmitted at the sending end varies. Therefore, the energy consumed by the energy dissipation resistor in a single fault may not reach the maximum energy consumption level of the resistor. Thus, it is necessary to calculate the total energy consumption level of the energy dissipation resistor in order to accurately assess the operating status of the energy dissipation resistor and improve the safety of the flexible DC converter valve operation.

[0070] In one embodiment, a non-contact current collector is installed on the energy leakage resistor; the steps for obtaining the active power of the energy leakage branch include:

[0071] It receives the current transmitted by the non-contact current collector and obtains the resistance value of the leakage resistor.

[0072] The active power is obtained by multiplying the square of the current by the resistance.

[0073] It should be noted that in this embodiment, a non-contact current collector is used to collect the current across the leakage resistor in order to calculate the active power. Based on Ohm's law, the active power across the leakage resistor can be calculated using the following formula:

[0074]

[0075] Where R is the resistance of the energy dissipation resistor, and I(t) is the current in the energy dissipation resistor collected at time t.

[0076] This embodiment achieves accurate measurement of the current in the leakage resistor by connecting a non-contact current acquisition device in series in the leakage branch, thereby accurately calculating the active power consumed and dissipated energy of the leakage resistor, providing a reliable basis for the operation monitoring, maintenance and performance optimization of the flexible DC converter valve.

[0077] In one embodiment, the non-contact current collector includes a Rogowski coil and an integrator;

[0078] The conductor at the input terminal of the energy dissipation resistor passes through the center of the Rogowski coil;

[0079] The integrator is connected to the Rogowski coil and is used to convert the differential voltage induced by the Rogowski coil into current.

[0080] In one embodiment, the non-contact current collector further includes a valve control unit;

[0081] The valve control unit is connected to the integrator to receive the current signal transmitted by the integrator and preprocess the current to obtain the processed current.

[0082] It should be noted that this embodiment uses a non-contact current acquisition device including a Rogowski coil and an integrator. A Rogowski coil is a current measuring device based on Faraday's law of electromagnetic induction. Its characteristics include a coreless, non-contact measurement capability, making it suitable for detecting high-frequency or pulsed currents. The output voltage of the Rogowski coil is proportional to the derivative of the measured current; by passing its output through an integrator, an output voltage proportional to the primary current can be obtained. In this embodiment, the center of the Rogowski coil passes through the front end (i.e., the input terminal) of the leakage resistor, ensuring accurate measurement of the DC current flowing through the leakage resistor and improving acquisition accuracy.

[0083] Specifically, the Rogowski coil collects the small voltage signal from the energy dissipation branch inside the power module, converts it into a current signal through an integrator, and transmits it to the valve control unit. The valve control unit performs preprocessing such as filtering and amplification on the received current signal to improve its quality and accuracy.

[0084] The following section will detail the acquisition principle of the non-contact current collector in this embodiment.

[0085] like Figure 2 As shown, Figure 2 In the diagram, Q1, Q2, Q3, Q4, and Q5 are power switches, D1, D2, D3, D4, and D5 are parasitic diodes on each power switch, R2 is a discharge resistor, RC is a Rogowski coil, and C is a capacitor.

[0086] like Figure 2 As shown, a Rogowski coil RC is installed at the input terminal of the energy dissipation resistor R2 in the energy dissipation branch, with the line conductor at the input terminal passing through the center of the Rogowski coil RC. When the power switch Q5 in the energy dissipation branch is switched on, current flows through the energy dissipation branch, and the Rogowski coil will induce a voltage. The magnitude of the voltage is proportional to the rate of change of current. The relationship between the induced voltage and the rate of change of current is shown below:

[0087]

[0088] v(t) is the voltage, d[i(t)] / dt is the rate of change of current, and M is the mutual inductance coefficient of the Rogowski coil, which represents the coil's ability to sense the rate of change of current on the north side. It is determined by the physical characteristics of the coil, such as the number of turns, cross-sectional area, and size, and is usually a fixed value. The value of M is determined after the Rogowski coil is selected.

[0089] The output of the Rogowski coil is the differential signal of the current. An integrator restores the voltage signal to the original current waveform, meaning the measured current is:

[0090]

[0091] The integrator outputs current through a fixed interface to the valve control unit. The valve control unit preprocesses the received current to obtain a preprocessed current. In one example, the current waveform of the energy dissipation branch is as follows: Figure 3 As shown.

[0092] Then, based on the pre-processed current and Ohm's law, the active power of the energy dissipation resistor can be calculated as follows:

[0093] .

[0094] In this embodiment, the operating status of the flexible DC converter valve is monitored by acquiring the average arm voltage and the temperature of the energy dissipation branch. When the average arm voltage is greater than the set voltage of the energy dissipation branch and a system fault signal is detected, the current time is acquired and recorded as the first time. When the average arm voltage is less than the set voltage and a system fault recovery signal is detected, the current time is acquired and recorded as the second time. The first and second times form a first time interval, which determines the time interval for the energy dissipation branch to be engaged and the energy dissipation during a single fault, providing technical support for accurately calculating the single energy dissipation of the energy dissipation branch. Furthermore, when the temperature of the energy dissipation branch is greater than a preset temperature... When the threshold voltage and the average voltage of the bridge arm are greater than the applied set voltage, the current time is acquired and recorded as the third time. The first time and the third time are combined to form a second time interval, which determines the time interval during which the energy dissipation branch is activated for energy dissipation during continuous faults, providing technical support for accurately calculating the total energy dissipation of the energy dissipation branch during continuous faults. By acquiring and integrating the active power of the energy dissipation branch in the first time interval, the single energy dissipation of the energy dissipation branch is obtained, realizing the accurate calculation of the single energy dissipation. By acquiring and integrating the active power of the energy dissipation branch in the second time interval, the total energy dissipation of the energy dissipation branch is obtained, realizing the accurate calculation of the total energy dissipation of the energy dissipation branch. Therefore, this embodiment can accurately calculate the energy dissipation of the energy dissipation branch in the power module, solving the technical problem that it is difficult to accurately calculate the energy dissipated by the energy dissipation branch in the prior art, realizing high-precision monitoring of the energy dissipation of the energy dissipation resistor, and improving the reliability of system protection.

[0095] Please see Figure 4 This invention provides a method for calculating the energy dissipation of a power module in a flexible DC converter valve, including:

[0096] 201. Obtain the average value of the bridge arm voltage and the temperature of the energy dissipation branch of the flexible DC converter valve;

[0097] 202. When the average voltage of the bridge arm is greater than the set voltage of the energy dissipation branch and a system fault signal is detected, the current time is acquired and recorded as the first time. When the average voltage of the bridge arm is less than the set voltage of the deactivation branch and a system fault recovery signal is detected, the current time is acquired and recorded as the second time. The first time and the second time constitute the first time interval.

[0098] 203. When the temperature of the energy dissipation branch is greater than the preset temperature threshold and the average voltage of the bridge arm is greater than the applied set voltage, the current time is obtained and recorded as the third time; the first time and the third time are combined to form the second time interval;

[0099] 204. Obtain and integrate the active power of the energy dissipation branch within the first time interval to obtain the single energy dissipation energy of the energy dissipation branch.

[0100] 205. Obtain and integrate the active power of the energy dissipation branch within the second time interval to obtain the total energy dissipation of the energy dissipation branch.

[0101] It should be noted that steps 201-205 can be referred to steps 101-105, and will not be repeated here.

[0102] 206. When the energy dissipated in a single instance exceeds the preset maximum energy consumption, or when the total energy dissipated exceeds the maximum energy consumption, an abnormal prompt will be output.

[0103] It should be noted that the preset maximum energy consumption refers to the maximum energy consumption of the leakage resistor.

[0104] In this embodiment, after calculating the single-cycle energy dissipation or total energy dissipation, the single-cycle energy dissipation or total energy dissipation is compared with the preset maximum energy consumption. When the single-cycle energy dissipation exceeds the maximum energy consumption or the total energy dissipation exceeds the preset maximum energy consumption, an abnormality prompt is output, indicating that the power module may have an abnormality and requires timely inspection and maintenance. The abnormality prompt may indicate that the energy dissipation of the energy leakage branch has reached its limit and should not be continued, thereby improving the safety of the energy leakage resistor.

[0105] In one example, the calculation results can also be stored in a database for long-term monitoring and analysis of the power module's operating status, providing a basis for optimizing the energy leakage branch design and improving the performance of the flexible DC converter valve system.

[0106] 207. When the temperature of the energy dissipation branch returns to the preset temperature threshold, the total energy dissipation is set to zero.

[0107] It should be noted that when the temperature of the energy dissipation resistor gradually rises from the equilibrium state and then returns to T1, the total energy consumption is set to zero so that the energy dissipation can be accumulated for the next cycle.

[0108] In this embodiment, the operating status of the flexible DC converter valve is monitored by acquiring the average arm voltage and the temperature of the energy dissipation branch. When the average arm voltage is greater than the set voltage for the energy dissipation branch and a system fault signal is detected, the current time is recorded as the first time. When the average arm voltage is less than the set voltage for the energy dissipation branch and a system fault recovery signal is detected, the current time is recorded as the second time. The first and second times form a first time interval, which determines the time interval for the energy dissipation branch to be activated and the energy consumed in a single fault, providing technical support for accurately calculating the single energy dissipation of the energy dissipation branch. Furthermore, when the temperature of the energy dissipation branch is greater than a preset temperature... When the threshold voltage and the average voltage of the bridge arm are greater than the applied set voltage, the current time is acquired and recorded as the third time. The first time and the third time are combined to form the second time interval, thus determining the time interval during which the energy dissipation branch is activated for energy dissipation during continuous faults. This provides technical support for accurately calculating the total energy dissipation of the energy dissipation branch during continuous faults. Furthermore, by acquiring and integrating the active power of the energy dissipation branch within the first time interval, the single energy dissipation of the energy dissipation branch is obtained, achieving accurate calculation of the single energy dissipation. Similarly, by acquiring and integrating the active power of the energy dissipation branch within the second time interval, the total energy dissipation of the energy dissipation branch is obtained, achieving accurate calculation of the total energy dissipation of the energy dissipation branch. In this embodiment, when the single energy dissipation exceeds the preset maximum energy consumption, or when the total energy dissipation exceeds the maximum energy consumption, an abnormality warning is output to improve the safety of the energy dissipation resistor. And when the temperature of the energy dissipation branch returns to the preset temperature threshold, the total energy dissipation is reset to zero to allow for the accumulation of the next energy dissipation.

[0109] Therefore, this embodiment can accurately calculate the energy dissipation of the energy leakage branch in the power module, solving the technical problem that the existing technology is difficult to accurately calculate the energy dissipated by the energy leakage branch, realizing high-precision monitoring of the energy dissipated by the energy leakage resistor, and improving the reliability of system protection.

[0110] It should be understood that, although Figure 1 and Figure 4 The steps in the flowchart are shown sequentially as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise explicitly stated herein, there is no strict order in which these steps are executed, and they can be performed in other orders. Figure 1 At least some of the steps in the process may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least some of the sub-steps or stages of other steps.

[0111] In one application example, such as Figure 5 As shown, Figure 5 In this context, N represents no, and Y represents yes. The practical application process of the method for calculating the energy dissipation of a flexible DC converter valve power module provided in this embodiment of the invention may include:

[0112] First, then determine if a fault has occurred;

[0113] If not, proceed to the step of determining whether a fault has occurred;

[0114] If yes, then determine whether the average voltage of the bridge arm module is greater than the set voltage. If no, end the process. If yes, receive the voltage signal output by the Rogowski coil and integrate it to obtain the discharge branch current. Then, calculate the active power of the discharge resistor and the energy dissipated by the discharge resistor this time. Then, calculate the cumulative value of the energy dissipated by the discharge resistor and determine whether the fault has been recovered. If recovered, determine whether the module voltage is less than the exit set value. If yes, end the process. If the fault has not been recovered or the module voltage is not less than the exit set value, jump to the step of receiving the voltage signal output by the Rogowski coil and integrating it to obtain the discharge branch current.

[0115] See Figure 6 The present invention provides a calculation device for the energy dissipation of a power module of a flexible DC converter valve, comprising:

[0116] The first acquisition module 301 is used to acquire the average value of the bridge arm voltage and the temperature of the energy dissipation branch of the flexible DC converter valve;

[0117] The first monitoring module 302 is used to acquire and record the current time as the first time when the average value of the bridge arm voltage is greater than the input set voltage of the energy leakage branch and a system fault signal is detected, and to acquire and record the current time as the second time when the average value of the bridge arm voltage is less than the exit set voltage and a system fault recovery signal is detected; and to form a first time interval by combining the first time and the second time.

[0118] The second monitoring module 303 is used to acquire and record the current time as the third time when the temperature of the energy leakage branch is greater than the preset temperature threshold and the average voltage of the bridge arm is greater than the applied fixed voltage, and to form a second time interval by combining the first time and the third time.

[0119] The second acquisition module 304 is used to acquire and integrate the active power of the energy dissipation branch within the first time interval to obtain the single energy dissipation energy of the energy dissipation branch.

[0120] The third acquisition module 305 is used to acquire and integrate the active power of the energy dissipation branch within the second time interval to obtain the total energy dissipation of the energy dissipation branch.

[0121] In one embodiment, it also includes:

[0122] The output module is used to output an abnormal prompt when the energy dissipated in a single instance exceeds the preset maximum energy consumption, or when the total energy dissipated exceeds the maximum energy consumption.

[0123] In one embodiment, it also includes:

[0124] The zeroing module is used to reset the total dissipated energy to zero when the temperature of the energy dissipation branch returns to a preset temperature threshold.

[0125] In one embodiment, this embodiment also provides an electronic device, the device including a processor and a memory:

[0126] The memory is used to store program code and transfer the program code to the processor;

[0127] The processor is used to execute the methods of any of the above embodiments according to instructions in the program code.

[0128] In one embodiment, this embodiment also provides a computer-readable storage medium for storing program code for performing the methods of any of the above embodiments.

[0129] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces, or indirect coupling or communication connection between apparatuses or units, and may be electrical, mechanical, or other forms.

[0130] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0131] Furthermore, in the various embodiments of the present invention, the functional units can be integrated into one processing unit, or each functional unit can be a separate physical entity, or two or more functional units can be integrated into one processing unit. The integrated unit described above can be implemented in hardware or as a software functional unit.

[0132] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0133] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented, for example, in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0134] It should also be noted that in the description of this invention, the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0135] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for calculating the energy dissipation of a power module in a flexible DC converter valve, characterized in that, The method includes: Obtain the average value of the bridge arm voltage and the temperature of the discharge branch of the flexible DC converter valve; When the average voltage of the bridge arm is greater than the set voltage of the energy dissipation branch and a system fault signal is detected, the current time is acquired and recorded as the first time. When the average voltage of the bridge arm is less than the set voltage of the exit and a system fault recovery signal is detected, the current time is acquired and recorded as the second time. The first time and the second time form a first time interval. When the temperature of the energy dissipation branch is greater than a preset temperature threshold and the average voltage of the bridge arm is greater than the applied fixed voltage, the current time is obtained and recorded as the third time; the first time and the third time are combined to form a second time interval. The active power of the energy dissipation branch within the first time interval is acquired and integrated to obtain the single energy dissipation of the energy dissipation branch. The active power of the energy dissipation branch within the second time interval is acquired and integrated to obtain the total energy dissipation of the energy dissipation branch.

2. The method according to claim 1, characterized in that, The method further includes: An error message is output when the energy dissipated in a single instance exceeds the preset maximum energy consumption, or when the total energy dissipated exceeds the maximum energy consumption.

3. The method according to claim 2, characterized in that, The method further includes: When the temperature of the energy dissipation branch returns to the preset temperature threshold, the total energy dissipation is set to zero.

4. The method according to claim 1, characterized in that, The energy dissipation branch includes an energy dissipation resistor, and a non-contact current collector is installed on the energy dissipation resistor; The steps for obtaining the active power of the energy leakage branch include: Receive the current transmitted by the non-contact current collector and obtain the resistance value of the leakage resistor; The active power is obtained by multiplying the square of the current by the resistance value.

5. The method according to claim 4, characterized in that, The non-contact current acquisition device includes a Rogowski coil and an integrator; The conductor at the input terminal of the energy-dissipating resistor passes through the center of the Rogowski coil; The integrator is connected to the Rogowski coil and is used to convert the differential voltage induced by the Rogowski coil into current.

6. A calculation device for the energy dissipation of a power module in a flexible DC converter valve, characterized in that, The device includes: The first acquisition module is used to acquire the average value of the bridge arm voltage and the temperature of the energy dissipation branch of the flexible DC converter valve; The first monitoring module is used to acquire and record the current time as the first time when the average voltage of the bridge arm is greater than the input set voltage of the energy leakage branch and a system fault signal is detected, and to acquire and record the current time as the second time when the average voltage of the bridge arm is less than the exit set voltage and a system fault recovery signal is detected; and to form a first time interval by combining the first time and the second time. The second monitoring module is used to acquire and record the current time as the third time when the temperature of the energy leakage branch is greater than a preset temperature threshold and the average voltage of the bridge arm is greater than the applied fixed voltage; and to form a second time interval by combining the first time and the third time. The second acquisition module is used to acquire and integrate the active power of the energy dissipation branch within the first time interval to obtain the single energy dissipation of the energy dissipation branch. The third acquisition module is used to acquire and integrate the active power of the energy-dissipating branch within the second time interval to obtain the total energy dissipation of the energy-dissipating branch.

7. The apparatus according to claim 6, characterized in that, Also includes: The output module is used to output an abnormal prompt when the single energy dissipation is greater than the preset maximum energy consumption, or when the total energy dissipation is greater than the maximum energy consumption.

8. The apparatus according to claim 7, characterized in that, Also includes: The zeroing module is used to zero out the total dissipated energy when the temperature of the energy dissipation branch returns to the preset temperature threshold.

9. An electronic device, characterized in that, The device includes a processor and a memory: The memory is used to store program code and transmit the program code to the processor; The processor is configured to execute the method as described in any one of claims 1-5 according to instructions in the program code.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium is used to store program code for performing the method as described in any one of claims 1-5.

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