Method and system for redundant switching of power supplies

Abstract

This application discloses a method and system for redundant switching of power generation and control systems, relating to the field of power redundancy process control technology. The method includes: acquiring the output voltage, output current, bus voltage, current direction, and operating temperature of a first and a second power generation and control channel; generating corresponding channel health parameters and configuring virtual impedance parameters for each power generation and control channel based on these parameters; adjusting the output current sharing ratio of the first and second power generation and control channels; increasing the virtual impedance parameter of any power generation and control channel when it meets an anomaly detection condition; generating a backflow risk parameter based on the difference in output voltage between the two power generation and control channels; and controlling another power generation and control channel to take over the power supply load when the backflow risk parameter meets the safe switching condition, and generating a redundancy switching result. This application improves the continuity and switching safety of power generation and control systems.

Description

Technical Field

[0001] This application relates to the field of power redundancy process control technology, and in particular to a power generation and control power redundancy switching method and system. Background Technology

[0002] Power generation and control equipment typically requires continuous operation under high reliability requirements. Its power supply system must not only meet the voltage and current stability requirements during normal operation, but also ensure uninterrupted power supply to critical loads such as the power generation and control loads, status acquisition loads, and safety interlock loads in the event of abnormal conditions such as undervoltage, overcurrent, overtemperature, or backflow in any power supply. Therefore, power generation and control equipment generally employs a dual- or multi-redundant power supply structure to improve power supply continuity and system safety.

[0003] Existing redundant power supply schemes mostly adopt a fixed primary / backup switching method, where one power supply serves as the primary power supply channel and the other as the backup channel. When the primary power supply channel fails, the system switches to the backup channel via relays, contactors, diodes, or electronic switches. While this method is simple in structure, it has the following problems in practical applications: First, the fixed primary / backup mode easily leads to the primary power supply channel operating at high load for extended periods, while the backup channel operates at low load or no load for extended periods, resulting in uneven aging of the two power supplies. Second, the switching action usually relies on a single voltage or current threshold, making it difficult to reflect the comprehensive status of the power supply channel, such as temperature rise, output fluctuations, and return current trends. Third, if the other channel directly takes over the entire load before the abnormal channel has fully reduced current or the residual voltage on the bus has been released, it may cause backflow, circulating current, or instantaneous current surges. Fourth, traditional hard switching methods easily introduce switching delays and device losses, which are detrimental to the continuous and stable operation of the power supply system.

[0004] Therefore, it is necessary to provide a method and system for redundant switching of power generation and control power supplies that can dynamically adjust the power supply sharing ratio according to the operating status of the two power generation and control power supply channels, and achieve safe takeover by combining backflow risk judgment during the current reduction process of abnormal channels. Summary of the Invention

[0005] This application provides a method and system for redundant switching of generator control power supply, which improves the continuity of generator control power supply and the safety of switching.

[0006] This application provides the following solution:

[0007] According to a first aspect, a method for redundant switching of a power generation control channel is provided. The method includes: acquiring the output voltage, output current, bus voltage, current direction, and operating temperature of a first power generation control channel and a second power generation control channel; generating corresponding channel health parameters based on the output current and operating temperature of each power generation control channel, and configuring virtual impedance parameters of each power generation control channel according to the channel health parameters; adjusting the output current sharing ratio of the first power generation control channel and the second power generation control channel based on the virtual impedance parameters; increasing the virtual impedance parameter of any power generation control channel when it meets the abnormal judgment condition, thereby reducing the output current ratio of that power generation control channel; generating a backflow risk parameter based on the difference between the output voltages of the two power generation control channels, the attenuation amplitude and attenuation rate of the bus voltage during the current reduction process in the abnormal channel, and the current direction; and controlling another power generation control channel to take over the power generation control load when the backflow risk parameter meets the safe switching condition, and generating a redundancy switching result.

[0008] According to the second aspect, a power supply redundancy switching system is provided, comprising: a sampling unit for acquiring the output voltage, output current, bus voltage, current direction, and operating temperature of a first power supply channel and a second power supply channel; a channel status processing unit for generating corresponding channel health parameters based on the output current and operating temperature of each power supply channel, and configuring virtual impedance parameters of each power supply channel according to the channel health parameters; a virtual impedance control unit for adjusting the output current sharing ratio of the first power supply channel and the second power supply channel based on the virtual impedance parameters; an anomaly stripping unit for increasing the virtual impedance parameter of any power supply channel to reduce the output current ratio of that power supply channel when any power supply channel meets the anomaly judgment condition; a backflow risk judgment unit for generating backflow risk parameters based on the difference between the output voltages of the two power supply channels, the attenuation amplitude and attenuation rate of the bus voltage during the current reduction process in the abnormal channel, and the current direction; and a takeover control unit for controlling another power supply channel to take over the power supply load when the backflow risk parameters meet the safe switching conditions, and generating a redundancy switching result.

[0009] According to the specific embodiments provided in this application, the following technical effects are disclosed:

[0010] This application collects voltage, current, bus voltage, current direction, and operating temperature data from two power supply channels to assess channel status in real time. It also dynamically adjusts the output current sharing ratio of the two power supplies using virtual impedance parameters, avoiding long-term high-load operation of a single channel due to fixed primary / backup power supply. When either channel malfunctions, its output share is reduced by increasing its virtual impedance, achieving soft disconnection of the malfunctioning channel. Simultaneously, it generates backflow risk parameters based on output voltage difference, bus residual voltage attenuation, and current direction. Only after meeting safe switching conditions is the other channel controlled to take over the load, thereby reducing backflow, circulating current, and switching impact risks, and improving the continuity and switching safety of power supply.

[0011] Of course, any product implementing this application does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0012] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0013] Figure 1 A flowchart of the power supply redundancy switching method provided in the embodiments of this application;

[0014] Figure 2 This is a flowchart illustrating the generation of channel health parameters and configuration of virtual impedance provided in an embodiment of this application.

[0015] Figure 3 A flowchart of output current sharing control based on virtual impedance provided in this application embodiment;

[0016] Figure 4 This is a structural block diagram of the power supply redundancy switching system provided in an embodiment of this application. Detailed Implementation

[0017] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0018] Figure 1 A flowchart of a power supply redundancy switching method provided in this application embodiment is shown in the figure. As illustrated, the method may include the following steps:

[0019] Step 101: Obtain the output voltage, output current, bus voltage, current direction, and operating temperature of the first and second power control channels.

[0020] Step 102: Generate corresponding channel health parameters based on the output current and operating temperature of each power control channel, and configure the virtual impedance parameters of each power control channel according to the channel health parameters.

[0021] Step 103: Adjust the output current sharing ratio of the first power control channel and the second power control channel based on the virtual impedance parameter.

[0022] Step 104: When any power control channel meets the abnormal judgment condition, increase the virtual impedance parameter of the power control channel to reduce the output current ratio of the power control channel.

[0023] Step 105: Generate backflow risk parameters based on the difference between the output voltages of the two power control channels, the attenuation magnitude and rate of the bus voltage during the abnormal channel current reduction process, and the current direction.

[0024] Step 106: When the backflow risk parameters meet the safe switching conditions, control another power supply channel to take over the power supply load and generate a redundancy switching result.

[0025] As can be seen from the above process, this application collects the voltage, current, bus voltage, current direction, and operating temperature of the two power supply channels to evaluate the channel status in real time. It also dynamically adjusts the output current sharing ratio of the two power supplies using virtual impedance parameters, avoiding long-term high-load operation of a single channel due to fixed primary and backup power supplies. When either channel malfunctions, its output share is reduced by increasing its virtual impedance, achieving soft disconnection of the malfunctioning channel. Simultaneously, it generates backflow risk parameters by combining output voltage difference, bus residual voltage attenuation status, and current direction. Only after meeting safe switching conditions is the other channel controlled to take over the load, thereby reducing the risks of backflow, circulating current, and switching impact, and improving the continuity and switching safety of power supply.

[0026] The following describes in detail each step of the above process and the effects that can be further produced, with reference to the embodiments.

[0027] Step 101 specifically involves obtaining the output voltage, output current, bus voltage, current direction, and operating temperature of the first and second power control channels.

[0028] The first and second power control channels are each equipped with independent voltage sampling branches, current sampling branches, and temperature sampling branches. The voltage sampling branch can be connected to the output terminal of each power control channel to obtain the output voltage before it reaches the power supply bus. The current sampling branch can be located between each power control channel and the power supply bus to obtain the output current of the corresponding channel. The temperature sampling branch can be located near the power devices, heat sink, or housing of the power module to obtain the operating temperature of the corresponding power control channel. Each sampling branch converts the acquired analog signals into electrical signals that the power controller can recognize, and then performs analog-to-digital conversion to form corresponding digital sampled data.

[0029] The bus voltage can be obtained through voltage sampling branches set at both ends of the power supply bus, reflecting the actual power supply status after the two power generation and control channels work together. Since the power supply bus directly supplies power to the load, the bus voltage can be used to determine whether the power supply at the load end is stable, and can also be used to identify the release of residual voltage on the bus during the current reduction process of the abnormal channel. The power controller can continuously collect the bus voltage according to a preset sampling period and filter the sampled values ​​to avoid the influence of transient noise on subsequent switching decisions.

[0030] The current direction can be obtained through a bidirectional current sampling circuit, a Hall current sensor, or a sampling circuit with direction recognition function. Specifically, when current flows from the generator control power channel to the power supply bus, this direction can be identified as the bus output direction; when current flows from the power supply bus to a generator control power channel, this direction can be identified as the bus return direction. By acquiring the current direction, the power controller can determine whether a power channel has the risk of reverse current absorption, backflow from the bus, or circulating current with another channel.

[0031] The aforementioned output voltage, output current, bus voltage, current direction, and operating temperature can be synchronously acquired by the power controller within the same sampling period, or sequentially acquired according to a preset order. After acquisition, the power controller can perform amplitude limiting, moving average, or continuous sampling confirmation processing on various types of sampled data, eliminating obviously abnormal transient sampling points, and using the processed data as the basis for subsequent channel health parameter generation, virtual impedance configuration, abnormal channel identification, and backflow risk assessment. This method ensures that subsequent redundancy switching control is not based solely on a single voltage anomaly trigger, but rather on the comprehensive operating status of both power supply channels and the power supply bus.

[0032] Step 102 specifically involves generating corresponding channel health parameters based on the output current and operating temperature of each power control channel, and configuring virtual impedance parameters for each power control channel based on the channel health parameters.

[0033] Figure 2This is a flowchart illustrating the channel health parameter generation and virtual impedance configuration provided in this application embodiment. The power controller collects the output current of the first and second power control channels according to a preset sampling period. To avoid instantaneous spikes or sampling noise directly affecting the judgment results, the power controller can perform a moving average processing on multiple output current sampling values ​​within the same sampling period to obtain a relatively stable current change trend within that sampling period. Simultaneously, the power controller records the maximum and minimum values ​​of the output current within that sampling period, and obtains the peak-to-peak current value from the difference between the maximum and minimum values. The peak-to-peak current value is used to characterize the output fluctuation degree of the corresponding power control channel within the current period; the larger the peak-to-peak current value, the more significant the load disturbance or current sharing regulation fluctuation experienced by the channel.

[0034] For operating temperature, the power controller can record the temperature sampling values ​​of each power control channel in adjacent sampling periods, calculate the change between the temperature value of the later sampling period and the temperature value of the previous sampling period, and then combine this with the time interval between two sampling periods to obtain the temperature rise rate. The temperature rise rate is used to characterize the thermal stress change of the corresponding power control channel. If a power control channel experiences a rapid temperature rise in a short period of time, even if its current temperature has not yet reached the over-temperature threshold, it can be considered that the channel is experiencing a trend of continuous high-load operation or a decrease in heat dissipation capacity.

[0035] After obtaining the peak-to-peak current and temperature rise rate, the power controller compares the peak-to-peak current with preset current fluctuation levels and the temperature rise rate with preset temperature rise levels. The current fluctuation levels categorize output current fluctuations into low, medium, and high fluctuation levels, while the temperature rise levels categorize thermal stress into low, medium, and high thermal stress levels. This categorization avoids directly using continuously changing sampled values ​​in subsequent control, reducing the controller's computational complexity and improving the stability of channel status judgment.

[0036] A preset channel status table can be pre-stored in the power controller's storage unit. This table uses current fluctuation level and thermal stress level as query conditions and records channel health parameters for different state combinations. For example, when both the current fluctuation level and thermal stress level are low, channel health parameters indicating a good channel status can be read; when either the current fluctuation level or thermal stress level is high, channel health parameters indicating a need for derating can be read; and when both the current fluctuation level and thermal stress level are high, channel health parameters indicating a protected state can be read. In this way, the source of channel health parameters is clear, and it can simultaneously reflect current output stability and temperature rise trends.

[0037] After obtaining the channel health parameters for each power control channel, the power controller compares these parameters with preset health thresholds to determine the health level of the corresponding power control channel. Health levels can include normal health level, derating health level, and protection health level. A normal health level indicates that the corresponding channel can participate in power supply according to the conventional current sharing strategy; a derating health level indicates that the corresponding channel can still participate in power supply but should not bear a large output current; and a protection health level indicates that the corresponding channel has a high operational risk and its power supply participation needs to be significantly reduced.

[0038] The power controller pre-stores a first virtual impedance value, a second virtual impedance value, and a third virtual impedance value, which increase sequentially. When the power supply channel is in normal health status, the power controller selects the first virtual impedance value as the virtual impedance parameter for that channel, enabling it to participate normally in current sharing between the two channels. When the power supply channel is in derating health status, the power controller selects the second virtual impedance value as the virtual impedance parameter. Since the second virtual impedance value is greater than the first virtual impedance value, the target output current proportion of that channel in subsequent current sharing control will be reduced. When the power supply channel is in protection health status, the power controller selects the third virtual impedance value as the virtual impedance parameter for that channel, further reducing the output current load of that channel and preventing it from continuing to operate under high-stress power supply conditions.

[0039] The aforementioned virtual impedance parameters can be written into the digital power control loop of the corresponding generator control power channel to modify the external characteristics of the channel's output voltage. Specifically, the larger the virtual impedance parameter, the greater the voltage setpoint correction for the corresponding channel under the same output current variation, and the more the output current of that channel will be suppressed in parallel power supply; the smaller the virtual impedance parameter, the stronger the output current carrying capacity of the corresponding channel. Therefore, the two generator control power channels no longer need to adopt a fixed primary / backup configuration, but can dynamically adjust the output sharing ratio according to their respective current fluctuations and temperature rise, thereby reducing the risk of aging and failure caused by long-term high-load operation of a single power supply.

[0040] Step 103 specifically involves adjusting the output current sharing ratio of the first power control channel and the second power control channel based on the virtual impedance parameters.

[0041] The power controller collects the actual output current of the first and second power supply channels during each current sharing control cycle. The actual output current is obtained by the current sampling circuit in the output circuit of each power supply channel, and is then filtered before being sent to the current sharing control program. Since both power supply channels supply power to the power bus, the actual output current of each channel reflects the actual distribution of the current load between the two power supplies.

[0042] After obtaining the virtual impedance parameters of each power supply channel, the power controller can determine the corresponding target output current range for each channel. Channels with smaller virtual impedance parameters are allowed to handle a larger proportion of power supply, so their target output current range can be set in a higher current range. Channels with larger virtual impedance parameters require less power supply involvement, so their target output current range can be set in a lower current range. By setting the target output current range, the simple equalization of current sharing between the two power supplies can be avoided; instead, the output current sharing ratio can be dynamically adjusted according to changes in the virtual impedance parameters.

[0043] As an feasible approach, the target output current range is determined according to the virtual impedance parameters of each power generation control channel. This includes: reading the virtual impedance parameters of the first and second power generation control channels and converting each virtual impedance parameter into a corresponding virtual admittance value; collecting the total load current of the power supply bus in the current current sharing control cycle and using the total load current as the current to be allocated for the two power generation control channels; allocating the current to be allocated according to the proportion of the virtual admittance value of each power generation control channel in the sum of the two virtual admittance values ​​to obtain the target sharing current of the corresponding power generation control channel; generating the upper limit and lower limit current values ​​of the corresponding power generation control channel according to a preset hysteresis width, with the target sharing current as the center; and determining the current range between the upper limit and the lower limit current values ​​as the target output current range of the power generation control channel. The target sharing current of the power generation control channel with the larger virtual impedance parameter is less than the target sharing current of the power generation control channel with the smaller virtual impedance parameter.

[0044] In practice, the power controller first reads the currently configured virtual impedance parameters of the first and second power generation control channels. Since a larger virtual impedance parameter indicates a reduced current load for the corresponding power generation control channel in parallel power supply, the power controller can convert the virtual impedance parameter into a corresponding virtual admittance value. The virtual admittance value and the virtual impedance parameter have an inverse relationship: a larger virtual impedance parameter corresponds to a smaller virtual admittance value, and vice versa. By introducing the virtual admittance value, the current load that each of the two power generation control channels should bear during the current current sharing control cycle can be determined more intuitively.

[0045] The total load current of the power supply bus can be obtained through a current sampling circuit located at the bus output terminal, or by adding the output currents of the first and second power generation control channels. After acquiring this total load current within the current sharing control cycle, the power controller uses it as the current to be shared by the two power generation control channels. Thus, the determination of the subsequent target current sharing is not a fixed ratio allocation detached from actual load demand, but rather based on the actual power consumption demand of the current power-supplied load.

[0046] After determining the current to be allocated, the power controller calculates the proportion of the virtual admittance value of each generator control power channel in the sum of the virtual admittance values ​​of the two channels, and allocates the current to be allocated according to this proportion, thus obtaining the target current shared by each generator control power channel. For example, when the virtual impedance parameter of the first generator control power channel is small and the virtual admittance value is large, its corresponding target current shared is large; when the virtual impedance parameter of the second generator control power channel is large and the virtual admittance value is small, its corresponding target current shared is small. This allows power channels in better health to carry more current, while power channels in poorer health or under derating conditions carry less current.

[0047] To avoid frequent fluctuations in the actual output current around the target shared current, which would cause repeated adjustments to the voltage setpoint, the power controller does not set the target shared current as a single judgment point. Instead, it sets a current hysteresis band centered on the target shared current. Specifically, preset hysteresis widths can be increased or decreased based on the target shared current to obtain corresponding upper and lower current limits. The range formed between the upper and lower current limits is the target output current range for this power supply channel.

[0048] By setting a target output current range, an allowable fluctuation range can be provided for current sharing control. When the actual output current of a certain power supply channel is within the corresponding target output current range, it indicates that the current sharing of that channel is within the allowable range, and the power controller can temporarily not adjust the voltage setpoint of that channel. When the actual output current is higher than the upper current limit, it indicates that the current carried by that channel is too large, and its voltage setpoint needs to be reduced. When the actual output current is lower than the lower current limit, it indicates that the current carried by that channel is too small, and its voltage setpoint needs to be increased. This method can reduce control jitter and improve the stability of current sharing regulation between the two power supply channels.

[0049] During current sharing regulation, the power controller compares the actual output current of each generator control power channel with the corresponding target output current range. When the actual output current of a generator control power channel is higher than the upper limit of the target output current range, it indicates that the output current handled by that channel is too large. The power controller lowers the voltage setpoint of that channel, causing the output voltage external characteristic of that channel to adjust slightly downward, thereby reducing its output current and allowing another generator control power channel to handle more current. When the actual output current of a generator control power channel is lower than the lower limit of the target output current range, it indicates that the output current handled by that channel is insufficient. The power controller increases the voltage setpoint of that channel, causing the output current of that channel to gradually increase.

[0050] The voltage setpoint can be understood as the control quantity used in the digital power supply control loop to determine the target output voltage of a channel. The power controller does not directly and drastically change the output voltage; instead, it adds a small correction to the original rated output voltage setpoint, causing the corresponding power supply channel to exhibit a droop characteristic that matches the virtual impedance. By adjusting the voltage setpoint, the output current can be redistributed between two power supply channels without changing the hardware connections.

[0051] To prevent frequent voltage setpoint fluctuations that could cause power bus oscillations, the power controller limits the adjustment range of each voltage setpoint. In other words, when it is necessary to increase or decrease the voltage setpoint of a specific power supply channel, each adjustment will not exceed a preset step value. This preset step value can be set to 0.02V and can be gradually completed over multiple current sharing control cycles. This method allows for smooth changes in the output current sharing ratio, avoiding bus voltage fluctuations, current competition between the two power supplies, or power supply disturbances to the power supply to the power control load caused by excessively rapid adjustments.

[0052] Through the above control process, the output current sharing ratio of the first and second power supply channels can dynamically change according to their respective virtual impedance parameters. When a channel has a poor health condition and is configured with a larger virtual impedance parameter, the target output current range of that channel decreases, and the power controller will reduce its voltage setpoint to reduce the current it bears. Conversely, when the other channel has a better health condition and is configured with a smaller virtual impedance parameter, the target output current range of that channel increases, and the power controller will allow it to bear more current. Thus, dynamic current sharing and adaptive current sharing based on health condition can be achieved between the two power supply channels.

[0053] Step 104 specifically involves: when any power control channel meets the abnormal judgment condition, increasing the virtual impedance parameter of that power control channel to reduce the output current ratio of that power control channel.

[0054] Figure 3This is a flowchart illustrating the output current sharing control based on virtual impedance provided in this application embodiment. The power controller continuously monitors the output voltage, output current, current direction, and operating temperature of the first and second power control channels, and compares the sampling results with preset thresholds. When the output voltage of a power control channel is lower than the preset undervoltage threshold for multiple consecutive sampling points, it indicates that the channel may experience a decrease in output capability, input abnormality, or internal voltage regulation failure. Using multiple consecutive sampling points for confirmation can avoid misjudgment caused by instantaneous load surges or sampling noise.

[0055] When the output current of a power supply channel exceeds the preset overcurrent threshold for multiple consecutive sampling points, it indicates that the channel may have excessive load, output short circuit, unbalanced load sharing, or control loop abnormality. The power controller does not immediately determine an anomaly based on a single overcurrent sampling point; instead, it requires the overcurrent state to persist across multiple sampling points, thereby improving the reliability of anomaly detection.

[0056] When the current direction of a certain generator control power supply channel switches from the bus output direction to the bus return direction, it indicates that the power supply bus may be supplying power in reverse to that generator control power supply channel. This situation may be caused by a collapse in the channel output voltage, an abnormal internal circuit, or an excessive voltage difference between the two power supplies. Since the return current phenomenon can easily lead to backflow, circulating current, or the faulty channel being dragged down by the healthy channel, once a current direction reversal is detected, it can be used as one of the abnormal judgment conditions.

[0057] When the operating temperature of a power control channel exceeds a preset over-temperature threshold and the duration exceeds a preset confirmation time, it indicates that the channel is under high thermal stress. Setting a duration confirmation condition is to avoid false triggering caused by instantaneous temperature fluctuations near the heatsink, sensor jitter, or short-term load peaks. By comprehensively judging multiple conditions such as undervoltage, overcurrent, backflow, and overtemperature, it can cover common risks to power control channels, including reduced output capacity, overload, backflow, and thermal runaway.

[0058] When any anomaly detection condition is met, the power controller marks the corresponding generator control power channel as an abnormal channel and latches the anomaly type. The abnormal channel marking is used to indicate the object of subsequent virtual impedance stripping control, and the anomaly type latching is used for fault recording, status reporting, and subsequent operation and maintenance analysis. Even if the abnormal signal disappears in a short time, the latching result can still be maintained until the end of this switching process, avoiding the abnormal channel from repeatedly entering or exiting the abnormal state due to sampling value jitter during the stripping process.

[0059] After a power supply channel is marked as an abnormal channel, the power controller first adjusts the current virtual impedance parameter of that abnormal channel from the current-sharing impedance value to the first stripping impedance value. The current-sharing impedance value corresponds to the virtual impedance state during normal parallel power supply, while the first stripping impedance value is greater than the current-sharing impedance value, used to reduce the current-carrying ratio of the abnormal channel in the power supply bus. By first increasing the virtual impedance instead of immediately disconnecting the channel, the abnormal channel can be gradually withdrawn from power supply sharing, reducing bus voltage drops and load power supply disturbances.

[0060] During the first observation period after the first stripping impedance value is applied, the power controller continuously collects the output current of the abnormal channel and calculates the decrease in output current of the abnormal channel. If the decrease in output current reaches the preset current reduction range, it indicates that the first stripping impedance value has effectively suppressed the output current of the abnormal channel. At this time, the first stripping impedance value is maintained, and the power supply bus voltage is continuously collected to determine whether the bus voltage is stable and whether there is a risk of reverse power flow.

[0061] If the output current decrease does not reach the preset current reduction range within the first observation period, it indicates that the abnormal channel is still carrying a large output current, or that the output circuit of that channel is still affecting the power supply bus. In this case, the power controller further adjusts the virtual impedance parameter of the abnormal channel from the first stripping impedance value to the second stripping impedance value. The second stripping impedance value is greater than the first stripping impedance value, which can further reduce the proportion of output current in the abnormal channel, allowing the healthy channel to gradually carry more power supply current.

[0062] Under the second stripping impedance value, the power controller continues to monitor the output current of the abnormal channel. If the output current of the abnormal channel is still higher than the preset residual current threshold, it indicates that simply increasing the virtual impedance is insufficient to effectively remove the abnormal channel from the power supply state, or that the channel may have serious problems such as short circuit, backflow absorption, or control failure. In this case, the power controller sets the output control of the abnormal channel to a latched state and maintains its virtual impedance parameter at the fault holding impedance value to prevent the abnormal channel from re-participating in power supply sharing.

[0063] The current sharing impedance, first stripping impedance, second stripping impedance, and fault holding impedance increase sequentially. This increasing relationship gives the exit process of the abnormal channel a stepped stripping characteristic; that is, first, a lower stripping intensity is used to observe whether the current decreases, and then the stripping intensity is increased further based on the effect of the output current decrease. Compared with directly disconnecting the abnormal channel, this method can reduce switching impact; compared with setting only a single fault impedance value, this method can confirm the stripping effect by the magnitude of the output current decrease, improving the stability and controllability of the power supply redundancy switching process.

[0064] Preferably, the process of increasing the virtual impedance parameter of the abnormal channel further includes: setting multiple candidate stripping impedance levels between the first stripping impedance value and the second stripping impedance value; collecting the output current of the abnormal channel, the output current of the other power supply channel, the total load current of the power supply bus, and the bus voltage before and after each adjustment of the virtual impedance parameter of the abnormal channel; determining a current transfer gap parameter based on the difference between the decrease in output current of the abnormal channel, the increase in output current of the other power supply channel, and the change in total load current, wherein the current transfer gap parameter is used to characterize the output current released by the abnormal channel and the output current actually received by the other power supply channel. The degree of unclosed connection between the virtual impedance parameters is determined; based on the lowest value of the bus voltage after each adjustment of the virtual impedance parameters and the time required for the bus voltage to recover to the preset stable voltage range, the bus support response parameters are determined; when the current transfer gap parameter does not exceed the preset gap threshold and the bus support response parameters meet the preset stability conditions, the candidate stripping impedance level with the larger impedance increment is selected from the remaining candidate stripping impedance levels as the next stripping impedance value; when the current transfer gap parameter exceeds the preset gap threshold, or the bus support response parameters do not meet the preset stability conditions, the higher candidate stripping impedance level adjacent to the current virtual impedance parameter is selected as the next stripping impedance value, and the corresponding observation time is extended.

[0065] In this embodiment, to avoid a sudden drop in power supply bus voltage or an excessively slow exit speed of the abnormal channel when increasing the virtual impedance in fixed steps, multiple candidate stripping impedance levels are pre-set between the first and second stripping impedance values. These candidate stripping impedance levels are arranged in ascending order of impedance value. Adjacent candidate stripping impedance levels can use the same impedance interval, or different impedance intervals can be set according to the rated output capacity of the abnormal channel, the current response speed of the other power supply channel, and the allowable voltage fluctuation range of the power supply bus. By setting multiple candidate stripping impedance levels, the output current of the abnormal channel can be gradually transferred to the other power supply channel, and a faster or slower stripping process can be selected based on the actual takeover status.

[0066] Before each adjustment of the virtual impedance parameters of the abnormal channel, the output current of the abnormal channel, the output current of the other power supply channel, the total load current of the power supply bus, and the bus voltage are recorded to form the baseline data before adjustment. After adjusting the virtual impedance parameters of the abnormal channel to a new candidate stripping impedance level, the above data is collected again after a preset response waiting time to form the post-adjustment response data. The preset response waiting time can be determined based on the voltage regulation cycle of the power supply channel, the stabilization time of the output filter, and the load dynamic response time to ensure that the collected data can reflect the actual current transfer effect generated by this virtual impedance adjustment.

[0067] The decrease in output current of the abnormal channel can be determined by the difference between the output current of the abnormal channel before and after adjustment, and the increase in output current of the other power supply channel can be determined by the difference between the output current of the other power supply channel before and after adjustment. Considering that the load of the power supply itself may change during the virtual impedance adjustment, the change in the total load current of the power supply bus is further calculated, and the increase in output current of the other power supply channel is corrected using the change in the total load current. By comparing the output current released by the abnormal channel with the actual output current received by the other power supply channel, the current transfer gap parameter is obtained.

[0068] For example, when the total load current of the power supply bus remains constant during impedance adjustment, the reduced output current of the abnormal channel should, in principle, be increased by the corresponding output current of the other power supply channel. If the output current of the abnormal channel decreases by ten amperes, while the output current of the other power supply channel only increases by six amperes, it indicates that there is still a four-ampere current transfer gap. This gap may be temporarily compensated by the bus energy storage element, or it may cause a drop in bus voltage. When the total load current of the power supply bus decreases simultaneously, the current change caused by the load reduction should be deducted to avoid misjudging the normal load removal as insufficient takeover by the other power supply channel. When the total load current of the power supply bus increases simultaneously, the increased load current should be included in the actual takeover current of the other power supply channel.

[0069] The bus support response parameter is used to evaluate the support capability of another power supply channel for the power supply bus when receiving the released current from an abnormal channel. Specifically, the bus voltage is continuously sampled after each virtual impedance adjustment to determine the minimum bus voltage after the adjustment, and the time required for the bus voltage to recover from the minimum bus voltage to a preset stable voltage range is recorded. The closer the minimum bus voltage is to the rated bus voltage and the shorter the recovery time, the stronger the transient takeover capability of the other power supply channel. If the minimum bus voltage is lower than the preset allowable lower voltage limit, or the bus voltage recovery time exceeds the preset recovery time threshold, it indicates that the current impedance adjustment amplitude may be too large, and the other power supply channel cannot stably receive the corresponding load current.

[0070] When the current transfer gap parameter does not exceed the preset gap threshold, and the minimum bus voltage and recovery time both meet the preset stability conditions, it indicates that the current released by the abnormal channel has been largely taken over by another power supply channel, and the power supply bus remains stable after this adjustment. At this time, a candidate stripping impedance level with a larger impedance increment can be selected from unused candidate stripping impedance levels as the next stripping impedance value, allowing the abnormal channel to exit power supply at a faster speed. The candidate stripping impedance level with a larger impedance increment can be an impedance level obtained by crossing one or more adjacent levels.

[0071] When the current transfer gap parameter exceeds the preset gap threshold, or the minimum bus voltage or bus voltage recovery time does not meet the preset stability conditions, it indicates that the takeover response of the other power supply channel is insufficient, or that the power supply bus has experienced significant dynamic fluctuations. In this case, instead of traversing multiple candidate stripping impedance levels, the higher candidate stripping impedance level adjacent to the current virtual impedance parameter is selected as the next stripping impedance value, and the observation time corresponding to that level is appropriately extended. By reducing the magnitude of a single virtual impedance increase, the impact of a sudden drop in the abnormal channel's output current on the power supply bus can be reduced, and sufficient response time can be reserved for the other power supply channel to increase its output current.

[0072] During the subsequent stripping process, the power controller repeatedly performs data acquisition, current transfer gap calculation, bus support response judgment, and candidate stripping impedance selection until the output current of the abnormal channel decreases below the preset residual current threshold, or the virtual impedance parameter increases to the second stripping impedance value. Therefore, the virtual impedance adjustment speed of the abnormal channel can adaptively change according to the actual takeover capability of the healthy channel and the dynamic stability state of the power supply bus, thereby shortening the fault channel exit time while reducing the probability of bus undervoltage, load power interruption, and current backflow.

[0073] Step 105 specifically involves generating backflow risk parameters based on the difference between the output voltages of the two power control channels, the attenuation magnitude and rate of the bus voltage during the abnormal channel current reduction process, and the current direction.

[0074] The backflow risk parameter is used to determine whether the abnormal channel may still have a dragging, backflow, or circulating current effect on the power supply bus before another power control channel takes over the power supply load. After the abnormal channel enters the current reduction process, the power controller starts to continuously monitor the output voltage, power supply bus voltage, and current direction of the two power control channels, and uses different risk flags to characterize the different sources of backflow risk.

[0075] The bus voltage decay rate is used to characterize how quickly the supply bus voltage decreases during an abnormal current reduction process. Specifically, the difference in bus voltage between adjacent sampling times can be calculated, and the ratio of this difference to the corresponding sampling time interval can be used as the bus voltage change rate for the current time period. Then, the maximum rate of decrease is selected from multiple current time period bus voltage change rates as the bus voltage decay rate. Alternatively, a bus voltage change curve can be fitted based on multiple consecutive sampling points, and the slope of the most significant decrease in the bus voltage change curve can be determined as the bus voltage decay rate. By using both the bus voltage decay amplitude and the bus voltage decay rate simultaneously, misjudgments caused by judging the bus stability state solely based on a single instantaneous voltage sampling value can be avoided.

[0076] The output voltage difference between the two power control channels is represented by a directed voltage difference. Specifically, the directed voltage difference is obtained by subtracting the output voltage of the abnormal channel from the output voltage of the other power control channel taking over the control task. The directed voltage difference not only indicates the magnitude of the voltage deviation between the two power control channels but also indicates the potential direction of current flow. When the output voltage of the other power control channel is significantly higher than the output voltage of the abnormal channel, current in the power supply bus may flow in reverse along the output terminal of the abnormal channel. Therefore, when the directed voltage difference exceeds a preset voltage difference threshold, a voltage difference risk flag is generated to indicate that there is a reverse current risk caused by voltage mismatch between the two channels.

[0077] The current direction can be obtained using bidirectional current detectors installed on the output branches of each generator control power supply channel. When current is detected flowing from the generator control power supply channel to the power supply bus, it is determined as the normal power supply direction; when current is detected flowing from the power supply bus to an abnormal channel, it is determined as the bus return direction, and a return current risk flag is generated. To prevent misjudgment caused by current sampling noise or transient power switch operation, the return current risk flag can be generated only after the reverse current continuously exceeds a preset return current threshold and continues for a preset confirmation time.

[0078] A bus instability risk flag is generated when the bus voltage decay exceeds a preset decay magnitude threshold or the bus voltage decay rate exceeds a preset decay rate threshold. The preset decay magnitude threshold is determined based on the minimum allowable supply voltage of the generator-controlled power supply load and the rated voltage of the power supply bus. The preset decay rate threshold is determined based on the load holding time, the bus energy storage capacity, and the current response speed of the other generator-controlled power supply channel. The bus instability risk flag indicates that the other generator-controlled power supply channel may currently be unable to compensate for the power gap caused by the abnormal channel's shutdown in a timely manner.

[0079] The power controller combines the differential voltage risk flag, bus instability risk flag, and return current risk flag to form the backflow risk parameter. When none of the three risk flags are generated, it indicates that the output voltage difference between the two generator control power supply channels is within the allowable range, the abnormal channel current reduction has not caused significant instability of the power supply bus, and no return current from the power supply bus to the abnormal channel has been detected. Therefore, the backflow risk parameter meets the safe switching conditions. At this time, the other generator control power supply channel is allowed to further increase its output current and take over the generator control power supply load released by the abnormal channel. When any risk flag has been generated, subsequent takeover actions are temporarily suspended, and the switching risk can be reduced by slowing down the abnormal channel current reduction rate, adjusting the voltage setpoint of the other generator control power supply channel, unloading low power supply retention level loads, or isolating the abnormal channel.

[0080] Step 106 specifically involves: when the backflow risk parameters meet the safe switching conditions, controlling another power supply channel to take over the power supply load and generating a redundancy switching result.

[0081] The backflow risk parameters meeting the safe switching conditions mean that the power controller confirms that the abnormal channel has basically withdrawn from power sharing, and that when another power control channel takes over the load, it will not generate reverse power supply, circulating current impact, or bus residual voltage superposition to the abnormal channel. This judgment can be made after the abnormal channel has completed the virtual impedance increase processing, or after the abnormal channel output current has dropped below the preset residual current threshold, to ensure that the abnormal channel is in a current reduction or disconnection state when the judgment is made.

[0082] The power controller can read the differential voltage risk flag, residual voltage risk flag, and backflow risk flag from the backflow risk parameters. When the output voltage difference between the first and second power control channels does not exceed the preset differential voltage threshold, it indicates that there is no significant potential difference conflict between the two power channels, and the differential voltage risk flag is unset. When the power supply bus voltage can decrease or recover to the preset stable voltage range within the preset residual voltage release time, it indicates that the bus residual voltage release process is normal, and the residual voltage risk flag is unset. When the current direction does not show a flow from the power supply bus to the abnormal channel, it indicates that no trend of the abnormal channel absorbing bus current is detected, and the backflow risk flag is unset.

[0083] When none of the three risk indicators are set, the power controller can determine that the backflow risk parameters meet the safe switching conditions. This indicates that there is no significant voltage difference between the abnormal channel and the healthy channel, the voltage state of the power supply bus is within the stable range that allows for takeover, and no reverse power supply from the bus to the abnormal channel is detected. Therefore, the other generator control power supply channel can take over the generator control power supply load with a lower backflow risk.

[0084] To improve the stability of the judgment, the power controller can also be set with a safety confirmation cycle. That is, only if the differential pressure risk flag, residual pressure risk flag, and backflow risk flag remain unset for multiple consecutive sampling cycles is the backflow risk parameter confirmed to meet the safe switching conditions. This avoids premature switching due to a single risk flag briefly disappearing due to instantaneous sampling fluctuations, thereby improving the reliability of the redundancy switching process.

[0085] After confirming that the safety switching conditions are met, the power controller can release the takeover waiting restriction on the other generator-controlled power channel and enter the load takeover control process. At this time, the other generator-controlled power channel can take over the generator-controlled power supply load corresponding to the continuous maintenance level first, and then gradually restore other loads according to the bus voltage recovery and the output current of the taken-over channel. By setting the safety switching conditions before load takeover, the redundant switching action can be based on the abnormal channel disconnection, bus status stabilization, and elimination of backflow risk, reducing the risks of backflow, circulating current, and switching impact.

[0086] In practical implementation, the power controller can pre-set power supply retention levels for the loads powered by the generator control system. Power supply retention levels indicate the power supply priority and permissible interruption level for different loads during redundancy switching. Continuous retention levels correspond to loads that cannot be powered down or experience significant power drops during switching, such as generator control units, status acquisition units, safety interlocking units, and critical communication units. Delayed recovery levels correspond to loads that are allowed to have their power restored only after the bus voltage has stabilized, such as auxiliary control units, non-critical communication expansion units, or recording units. Offloadable levels correspond to loads that can be temporarily disconnected or have their restoration delayed during switching, such as auxiliary loads like display units, lighting units, and non-essential notification units.

[0087] Once the backflow risk parameters meet the safe switching conditions, it indicates that the abnormal channel has completed current reduction or disconnection, there is no obvious residual voltage release abnormality on the power supply bus, and no trend of backflow from the bus to the abnormal channel is detected. At this time, the power controller first controls another generator control power supply channel to take over the generator control power supply load corresponding to the continuous maintenance level. This process can be achieved by controlling the output enable signal of the electronic switch, load enable terminal, distribution switch, or power management chip, so that the critical generator control load can obtain stable power supply first during the switching process, avoiding interruption of the generator control process or loss of safety lockout status.

[0088] After the continuous load takeover is completed, the power controller continues to collect the power supply bus voltage and determine whether the power supply bus voltage has recovered to the preset stable voltage range. The preset stable voltage range can be set according to the rated voltage of the generator control power supply system and the allowable fluctuation range of the load. When the bus voltage enters this stable range and remains so for a preset time, it indicates that the other generator control power supply channel is able to stably support the critical load. At this point, the other generator control power supply channel is then controlled to take over the generator control power supply load corresponding to the delayed recovery level. In this way, it is possible to avoid secondary voltage drops caused by restoring too much load simultaneously before the bus has stabilized.

[0089] For loads supplied by the generator control system corresponding to the offloadable level, the power controller can resume operation only if the output current of the other generator control power channel does not exceed the preset takeover current limit. The preset takeover current limit can be determined based on the rated output capacity, short-term overload capacity, and heat dissipation capacity of the other generator control power channel. If the output current of the other generator control power channel is close to or exceeds the takeover current limit, the resumption of the offloadable level load is temporarily suspended to prevent the healthy channel from entering an overcurrent or overheating state during the takeover process. If the output current is within the allowable range, the offloadable level load is gradually resumed to restore the generator control system to a complete power supply state.

[0090] After completing the aforementioned tiered takeover, the power controller verifies the redundancy switching process. Specifically, the power controller detects whether a voltage interruption occurs during the switching process for the loads supplied by the continuous maintenance level, and checks whether the output current of the abnormal channel is lower than a preset residual current threshold. If no voltage interruption occurs for the loads in the continuous maintenance level, and the output current of the abnormal channel has decreased to below the preset residual current threshold, it indicates that the critical load is supplied with continuous power, the abnormal channel has essentially withdrawn from power sharing, and a successful switching result can be generated.

[0091] If the power supply load corresponding to the continuous maintenance level experiences a voltage interruption during the switching process, or if the output current of the abnormal channel fails to decrease below the preset residual current threshold, it indicates that there is insufficient power supply continuity or inadequate abnormal channel stripping during the takeover process. The power controller generates a switching anomaly result. This anomaly result can be used to trigger alarms, record fault data, maintain abnormal channel lockout, or prevent the recovery of unloadable loads. In this way, this application not only completes the takeover control of another power supply channel but also provides closed-loop confirmation of the switching result, improving the controllability and safety of the redundant switching process.

[0092] To further illustrate the technical effects of the present invention, a specific embodiment and its test results are provided.

[0093] The redundant switching system for the generator control power supply employs two DC generator control power supply channels with a rated output voltage of 28V and a rated output current of 20A, connected in parallel to the same power supply bus. The power supply bus supplies power to the generator control load, status acquisition load, safety interlock load, communication load, and auxiliary display load. The power controller samples the output voltage, output current, bus voltage, current direction, and operating temperature of the two generator control power supply channels with a 1ms sampling period, and calculates the peak-to-peak current and temperature rise rate with a 100ms channel health assessment period. The preset undervoltage threshold is 25.2V, the preset overcurrent threshold is 22A, the preset overtemperature threshold is 75℃, the preset stable voltage range is 26.6V to 29.4V, and the preset residual current threshold is 0.5A. The first virtual impedance value corresponding to the normal health level is 30mΩ, the second virtual impedance value corresponding to the derating health level is 80mΩ, and the third virtual impedance value corresponding to the protection health level is 160mΩ. When disconnecting abnormal channels, the first disconnect impedance value is 300mΩ, the second disconnect impedance value is 800mΩ, and the fault holding impedance value is 1.5Ω. In the power supply load, the power control load, status acquisition load, and safety interlock load are set to the continuous holding level, the communication load is set to the delayed recovery level, and the auxiliary display load is set to the unloadable level.

[0094] To verify the redundancy switching effect of the proposed solution, a redundant power supply test platform for the generator control power supply was built, and normal current sharing test, channel derating test, abnormal channel stripping test, and backflow risk control test were conducted. In the normal current sharing test, the total load current of the power supply bus was set to 18A. When both the first and second generator control power supply channels were in normal health, the average output current of the two channels were 9.12A and 8.88A, respectively, with a current sharing deviation of 2.7%. The power supply bus voltage remained stable between 27.93V and 28.08V, and no visible voltage drop was observed.

[0095] In the channel derating test, the temperature of the heatsink of the first power control channel was increased to a rate of temperature rise of 1.6℃ / min, bringing it into the derating health level. After the power controller adjusted the virtual impedance parameter of the first power control channel from 30mΩ to 80mΩ, under a total load current of 18A, the average output current of the first power control channel decreased from 9.10A to 6.72A, and the average output current of the second power control channel increased from 8.90A to 11.28A. The adjustment process lasted 420ms, and the lowest bus voltage was 27.62V. The test results show that this application can dynamically change the current sharing ratio of the two power supplies according to the channel health status without disconnecting the power supply channels, thereby reducing the output burden of high thermal stress channels.

[0096] In the abnormal channel stripping test, the output of the first power control channel was simulated as an undervoltage anomaly, with its output voltage dropping below 25.2V for five consecutive sampling points. Within 6ms, the power controller marked the first power control channel as an abnormal channel and adjusted its virtual impedance parameter from the current-sharing impedance value to the first stripping impedance value of 300mΩ. Within the first observation time of 20ms, the output current of the first power control channel decreased from 8.94A to 2.36A, reaching the preset current reduction range. The power controller maintained the first stripping impedance value and continued to sample the bus voltage. Throughout the stripping process, the minimum voltage at the load terminal was maintained at 26.91V without any power interruption. Within 35ms, the second power control channel increased its output current to 17.42A, achieving continuous power supply to the critical load.

[0097] In further overcurrent anomaly testing, the simulated output current of the first generator control power channel was increased to 24.5A and continuously exceeded the continuous sampling confirmation condition. After the power controller marked the first generator control power channel as an abnormal channel, it first adjusted the virtual impedance parameter to the first stripping impedance value of 300mΩ. Since the output current only dropped to 8.20A within the first observation time, which did not reach the preset current reduction range, the power controller continued to adjust the virtual impedance parameter to the second stripping impedance value of 800mΩ. After adjustment, the output current of the first generator control power channel dropped to 0.42A within 18ms, which was lower than the preset residual current threshold and did not trigger output blocking. During the test, the lowest bus voltage was 26.74V, and the load remained continuously maintained without voltage interruption. The switching result was determined to be successful.

[0098] In the backflow risk control test, the output terminal of the abnormal channel was set to a low-potential absorption state, causing a tendency for current to flow back to the abnormal channel from the power supply bus. The power controller detected the current flowing from the power supply bus to the abnormal channel and set a backflow risk flag, temporarily suspending full-load takeover of another power control channel. When the virtual impedance parameter of the abnormal channel increased to the fault holding impedance value of 1.5Ω, the backflow current decreased from 1.28A to 0.09A, and the backflow risk flag was removed; simultaneously, the bus voltage recovered to 27.86V within 12ms, not exceeding the preset residual voltage release time. Subsequently, the power controller first restored the continuous holding level load, then the delayed recovery level load, and finally the unloadable level load when the output current of the takenover channel was below 19A. Test results showed that after adopting the solution of this application, the peak backflow current of the abnormal channel decreased from 3.46A without backflow risk control to 1.28A, a reduction of approximately 63.0%, and the voltage at the critical load terminal did not exhibit an unstable state below 26.6V.

[0099] According to another embodiment, a power supply redundancy switching system is provided. Figure 4A schematic block diagram of the power supply redundancy switching system according to one embodiment is shown. Figure 4 As shown, the system includes:

[0100] The sampling unit 401 is used to acquire the output voltage, output current, bus voltage, current direction and operating temperature of the first power control channel and the second power control channel.

[0101] The channel status processing unit 402 is used to generate corresponding channel health parameters based on the output current and operating temperature of each power control channel, and configure the virtual impedance parameters of each power control channel according to the channel health parameters.

[0102] The virtual impedance control unit 403 is used to adjust the output current sharing ratio of the first power control channel and the second power control channel based on the virtual impedance parameters.

[0103] The abnormality stripping unit 404 is used to increase the virtual impedance parameter of any power control channel when the abnormality judgment condition is met, so as to reduce the output current ratio of the power control channel.

[0104] The backflow risk judgment unit 405 is used to generate backflow risk parameters based on the difference between the output voltages of the two power control channels, the attenuation amplitude and attenuation rate of the bus voltage during the abnormal channel current reduction process, and the current direction.

[0105] The takeover control unit 406 is used to control another generator control power supply channel to take over the generator control power supply load and generate a redundancy switching result when the backflow risk parameters meet the safety switching conditions.

[0106] As an implementable approach, when the channel status processing unit 402 generates corresponding channel health parameters based on the output current and operating temperature of each power generation control channel, it includes: performing a moving average processing on the output current of each power generation control channel within a preset sampling period and recording the corresponding current peak-to-peak value; recording the operating temperature change of each power generation control channel within adjacent sampling periods and calculating the corresponding temperature rise rate; comparing the current peak-to-peak value and the temperature rise rate with preset current fluctuation levels and preset temperature rise levels, respectively, to determine the current fluctuation level and thermal stress level of the corresponding power generation control channel; and using the current fluctuation level and the thermal stress level as lookup indexes to read the corresponding channel health parameters from a preset channel status table.

[0107] As one feasible approach, when configuring the virtual impedance parameters of each power control channel based on the channel health parameters, the channel status processing unit 402 includes: comparing the channel health parameters of each power control channel with preset health thresholds to determine the health level of the corresponding power control channel; when the power control channel is in a normal health level, selecting a first virtual impedance value as the virtual impedance parameter of that power control channel; when the power control channel is in a derating health level, selecting a second virtual impedance value greater than the first virtual impedance value as the virtual impedance parameter of that power control channel; when the power control channel is in a protection health level, selecting a third virtual impedance value greater than the second virtual impedance value as the virtual impedance parameter of that power control channel; wherein, the first virtual impedance value, the second virtual impedance value, and the third virtual impedance value are pre-stored in the power controller.

[0108] As one feasible approach, when the virtual impedance control unit 403 adjusts the output current sharing ratio of the first and second power control channels based on the virtual impedance parameters, it includes: acquiring the actual output current of the first and second power control channels; determining the corresponding target output current range according to the virtual impedance parameters of each power control channel; reducing the voltage setpoint of the power control channel when the actual output current of any power control channel is higher than the upper limit of the corresponding target output current range; increasing the voltage setpoint of the power control channel when the actual output current of any power control channel is lower than the lower limit of the corresponding target output current range; wherein the single adjustment range of the voltage setpoint does not exceed a preset step value.

[0109] As an implementable approach, the virtual impedance control unit 403, when determining the corresponding target output current range according to the virtual impedance parameters corresponding to each generator control power channel, includes: reading the virtual impedance parameters corresponding to the first generator control power channel and the second generator control power channel, and converting each virtual impedance parameter into a corresponding virtual admittance value; collecting the total load current of the power supply bus in the current current sharing control cycle, and using the total load current as the current to be allocated for the two generator control power channels; allocating the current to be allocated according to the proportion of the virtual admittance value corresponding to each generator control power channel in the sum of the two virtual admittance values, to obtain the target sharing current of the corresponding generator control power channel; generating the upper limit value and lower limit value of the current for the corresponding generator control power channel according to a preset hysteresis width, with the target sharing current as the center; determining the current range between the upper limit value and the lower limit value as the target output current range of the generator control power channel; wherein, the target sharing current corresponding to the generator control power channel with a larger virtual impedance parameter is less than the target sharing current corresponding to the generator control power channel with a smaller virtual impedance parameter.

[0110] As one feasible approach, when any power control channel meets the abnormality determination conditions, the anomaly stripping unit 404 includes the following: the output voltage of the power control channel is lower than a preset undervoltage threshold for multiple consecutive sampling points; or the output current of the power control channel is higher than a preset overcurrent threshold for multiple consecutive sampling points; or the current direction of the power control channel changes from the bus output direction to the bus return direction; or the operating temperature of the power control channel is higher than a preset overtemperature threshold and the duration exceeds a preset confirmation time. When any abnormality determination condition is met, the corresponding power control channel is marked as an abnormal channel, and the abnormality type is latched.

[0111] As an implementable method, when the abnormality stripping unit 404 increases the virtual impedance parameter of the power control channel, it includes: after the power control channel is marked as an abnormal channel, adjusting the current virtual impedance parameter of the abnormal channel from the current sharing impedance value to a first stripping impedance value, and collecting the output current decrease of the abnormal channel within a first observation time; when the output current decrease reaches a preset current reduction range, maintaining the first stripping impedance value, and continuing to collect the power supply bus voltage; when the output current decrease does not reach the preset current reduction range, adjusting the virtual impedance parameter of the abnormal channel from the first stripping impedance value to a second stripping impedance value, wherein the second stripping impedance value is greater than the first stripping impedance value; under the action of the second stripping impedance value, if the output current of the abnormal channel is still higher than a preset residual current threshold, then setting the output control of the abnormal channel to a locked state, and maintaining its virtual impedance parameter at the fault holding impedance value; wherein the current sharing impedance value, the first stripping impedance value, the second stripping impedance value, and the fault holding impedance value increase sequentially.

[0112] As an implementable approach, the backflow risk judgment unit 405 generates backflow risk parameters based on the difference between the output voltages of the two power control channels, the attenuation magnitude and rate of the bus voltage during the current reduction process in the abnormal channel, and the current direction. This includes: calculating the difference between the output voltages of the first and second power control channels, and setting a differential voltage risk flag when the difference exceeds a preset differential voltage threshold; continuously acquiring the power supply bus voltage and recording the time required for the bus voltage to drop from its current value to a preset stable voltage range; setting a residual voltage risk flag when the time exceeds a preset residual voltage release time, or when the bus voltage does not drop to the preset stable voltage range within a preset observation time; setting a return current risk flag when current is detected flowing from the power supply bus to the abnormal channel; and using the differential voltage risk flag, residual voltage risk flag, and return current risk flag as the backflow risk parameters.

[0113] As one feasible approach, when the takeover control unit 406 controls another generator control power channel to take over the generator control power supply load and generates a redundancy switching result, the following steps are taken: A power supply maintenance level is pre-set for the generator control power supply load, wherein the power supply maintenance level includes at least a continuous maintenance level, a delayed recovery level, and a load shedding level; first, the other generator control power channel is controlled to take over the generator control power supply load corresponding to the continuous maintenance level; after the power supply bus voltage recovers to a preset stable voltage range, the other generator control power channel is controlled to take over the generator control power supply load corresponding to the delayed recovery level; when the output current of the other generator control power channel does not exceed a preset takeover current upper limit, the generator control power supply load corresponding to the load shedding level is restored; when the generator control power supply load corresponding to the continuous maintenance level does not experience a voltage interruption during the switching process, and the output current of the abnormal channel is lower than a preset residual current threshold, a successful switching result is generated; otherwise, an abnormal switching result is generated.

[0114] The technical solutions provided in this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A method for controlling power supply redundancy switching, characterized in that, The method includes: Obtain the output voltage, output current, bus voltage, current direction, and operating temperature of the first and second power control channels; Based on the output current and operating temperature of each power control channel, corresponding channel health parameters are generated, and virtual impedance parameters of each power control channel are configured according to the channel health parameters. The output current sharing ratio of the first power control channel and the second power control channel is adjusted based on the virtual impedance parameters. When any power control channel meets the abnormal judgment condition, the virtual impedance parameter of the power control channel is increased to reduce the output current ratio of the power control channel. Based on the difference between the output voltages of the two power control channels, the attenuation magnitude and rate of the bus voltage during the abnormal channel current reduction process, and the current direction, reverse injection risk parameters are generated. When the backflow risk parameters meet the safe switching conditions, another power supply channel is controlled to take over the power supply load and generate a redundant switching result.

2. The method of claim 1, wherein, The generation of corresponding channel health parameters based on the output current and operating temperature of each power control channel includes: Within a preset sampling period, the output current of each power control channel is processed by moving average, and the corresponding peak-to-peak current is recorded. Record the temperature change of each power control channel in adjacent sampling periods and calculate the corresponding temperature rise rate. The peak-to-peak current and the rate of temperature rise are compared with preset current fluctuation levels and preset temperature rise levels, respectively, to determine the current fluctuation level and thermal stress level of the corresponding power supply channel. Using the current fluctuation level and the thermal stress level as lookup indexes, the corresponding channel health parameters are read from the preset channel status table.

3. The method of claim 2, wherein, The configuration of virtual impedance parameters for each power control channel based on the channel health parameters includes: The channel health parameters of each power control channel are compared with the preset health threshold to determine the health level of the corresponding power control channel. When the power supply channel of the generator control is in a normal health level, the first virtual impedance value is selected as the virtual impedance parameter of the power supply channel of the generator control. When the power control channel is in the derating health level, a second virtual impedance value greater than the first virtual impedance value is selected as the virtual impedance parameter of the power control channel. When the power supply channel is in the protection health level, a third virtual impedance value greater than the second virtual impedance value is selected as the virtual impedance parameter of the power supply channel. The first virtual impedance value, the second virtual impedance value, and the third virtual impedance value are pre-stored in the power controller.

4. The method of claim 1, wherein, The adjustment of the output current sharing ratio of the first and second power control channels based on the virtual impedance parameters includes: Collect the actual output current of the first and second power control channels; Determine the corresponding target output current range according to the virtual impedance parameters of each power control channel; When the actual output current of any generator control power supply channel is higher than the upper limit of the corresponding target output current range, the voltage setpoint of that generator control power supply channel is reduced. When the actual output current of any generator control power supply channel is lower than the lower limit of the corresponding target output current range, increase the voltage setpoint of that generator control power supply channel; Wherein, the single adjustment range of the voltage setpoint does not exceed a preset step value.

5. The method of claim 4, wherein, The step of determining the corresponding target output current range according to the virtual impedance parameters of each power control channel includes: Read the virtual impedance parameters corresponding to the first and second power control channels, and convert each virtual impedance parameter into the corresponding virtual admittance value. Collect the total load current of the power supply bus in the current current sharing control cycle, and use the total load current as the current to be allocated for the two power generation and control channels; The current to be allocated is distributed according to the proportion of the virtual admittance value of each power control channel in the sum of the two virtual admittance values, so as to obtain the target sharing current of the corresponding power control channel. Centered on the target current sharing, the upper limit and lower limit values ​​of the current for the corresponding power control channel are generated according to the preset hysteresis width. The current range between the upper current limit and the lower current limit is defined as the target output current range of the power supply channel. Among them, the target sharing current of the power generation control channel with a larger virtual impedance parameter is smaller than the target sharing current of the power generation control channel with a smaller virtual impedance parameter.

6. The method of claim 1, wherein, The abnormality determination conditions for any of the power control channels include: The output voltage of the power control channel is lower than the preset undervoltage threshold at multiple consecutive sampling points; Alternatively, the output current of the power control channel may exceed the preset overcurrent threshold for multiple consecutive sampling points; Alternatively, the current direction of the power supply channel can be switched from the bus output direction to the bus return direction; Alternatively, the operating temperature of the power control channel is higher than the preset over-temperature threshold and the duration exceeds the preset confirmation time; When any abnormality determination condition is met, the corresponding power control channel is marked as an abnormal channel, and the abnormality type is latched.

7. The method of claim 6, wherein, The improvement of the virtual impedance parameter of the power control channel includes: After the power control channel is marked as an abnormal channel, the current virtual impedance parameter of the abnormal channel is adjusted from the current sharing impedance value to the first stripping impedance value, and the output current drop of the abnormal channel is collected during the first observation time. When the output current decreases to the preset current reduction level, the first stripping impedance value is maintained, and the power supply bus voltage is continued to be collected. When the output current decrease does not reach the preset current reduction range, the virtual impedance parameter of the abnormal channel is adjusted from the first stripping impedance value to the second stripping impedance value, where the second stripping impedance value is greater than the first stripping impedance value. Under the action of the second stripping impedance value, if the output current of the abnormal channel is still higher than the preset residual current threshold, the output control of the abnormal channel is set to the lockout state, and its virtual impedance parameter is kept at the fault holding impedance value. The current sharing impedance value, the first stripping impedance value, the second stripping impedance value, and the fault holding impedance value increase sequentially.

8. The method according to claim 1, characterized in that, The reverse feed risk parameters are generated based on the difference in output voltage between the two power control channels, the attenuation magnitude and rate of the bus voltage during the abnormal channel current reduction process, and the current direction, including: When the abnormal channel begins to reduce the output current, the bus voltage is recorded as the bus reference voltage, and the bus voltage during the abnormal channel current reduction process is continuously collected. Determine the lowest bus voltage during the abnormal channel current reduction process, determine the bus voltage attenuation amplitude based on the difference between the bus reference voltage and the lowest bus voltage, and determine the bus voltage attenuation rate based on the bus voltage change at adjacent sampling times and the corresponding sampling time interval. Calculate the directed voltage difference between the output voltage of the other power control channel and the output voltage of the abnormal channel; When the directional voltage difference exceeds a preset voltage difference threshold, a voltage difference risk flag is generated; When the bus voltage attenuation exceeds a preset attenuation threshold, or the bus voltage attenuation rate exceeds a preset attenuation rate threshold, a bus instability risk flag is generated. When current is detected flowing from the power supply bus to the abnormal channel, a backflow risk flag is generated; The backflow risk parameters are generated based on the differential pressure risk indicator, the busbar instability risk indicator, and the reflux risk indicator.

9. The method of claim 1, wherein, The control of another power supply channel to take over the power supply load and generate redundancy switching results includes: A power supply retention level is pre-set for the power supply load of the generator control system. The power supply retention level includes at least a continuous retention level, a delayed recovery level, and an unloadable level. First, control another generator control power supply channel to take over the generator control power supply load corresponding to the continuous maintenance level; After the power supply bus voltage recovers to the preset stable voltage range, another generator control power supply channel takes over the generator control power supply load corresponding to the delayed recovery level; When the output current of another generator control power supply channel does not exceed the preset upper limit of the control current, restore the generator control power supply load corresponding to the unloadable level; If the power supply load corresponding to the continuous maintenance level does not experience voltage interruption during the switching process, and the output current of the abnormal channel is lower than the preset residual current threshold, a successful switching result is generated; otherwise, an abnormal switching result is generated.

10. A power supply redundancy switching system, comprising: include: The sampling unit is used to acquire the output voltage, output current, bus voltage, current direction, and operating temperature of the first and second power control channels. The channel status processing unit is used to generate corresponding channel health parameters based on the output current and operating temperature of each power control channel, and configure the virtual impedance parameters of each power control channel according to the channel health parameters. A virtual impedance control unit is used to adjust the output current sharing ratio of the first power control channel and the second power control channel based on the virtual impedance parameters. An abnormality stripping unit is used to increase the virtual impedance parameter of any power control channel when the abnormality judgment condition is met, so as to reduce the output current ratio of the power control channel. The backflow risk judgment unit is used to generate backflow risk parameters based on the difference between the output voltages of the two power control channels, the attenuation amplitude and attenuation rate of the bus voltage during the abnormal channel current reduction process, and the current direction. The takeover control unit is used to control another generator control power supply channel to take over the generator control power supply load and generate a redundancy switching result when the backflow risk parameters meet the safety switching conditions.

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