425results about "Power supply lines" patented technology

The invention relates to a railway traction substation state monitoring method and system, equipment and a medium. The monitoring method comprises the following steps: acquiring real-time monitoring data of the equipment in a railway traction substation; performing data preprocessing on the real-time monitoring data to obtain a preprocessed monitoring data set, performing protocol identification, and converting heterogeneous data in the monitoring data set into structured data according to a preset protocol template library; based on the structured data, time-frequency domain characteristic parameters of the equipment are extracted, and a multi-dimensional characteristic matrix is constructed; inputting the multi-dimensional feature matrix into a pre-trained hybrid diagnosis model, and generating an equipment health degree score and a fault probability value; according to the health degree score and the fault probability value, generating an early warning instruction in combination with a dynamic threshold algorithm; and generating a priority maintenance strategy through a maintenance strategy optimization model based on the early warning instruction and the equipment maintenance resource constraint condition. According to the invention, accurate perception and intelligent decision making of the equipment state are realized in a multi-source heterogeneous data environment.

The invention provides a railway flexible traction system based on multi-source fusion. The system is composed of a central control unit, a V / v traction transformer unit and a multi-port flexible interconnection unit. The V / v traction transformer unit comprises a first power supply arm, a second power supply arm and a third power supply arm, the input ends of the V / v traction transformer unit are connected with a public power grid, the first and second power supply arms are connected to the multi-port flexible interconnection unit, and the third power supply arm provides passive support for a traction network. The multi-port flexible interconnection unit comprises a two-phase rectification module, a photovoltaic power generation module, an energy storage module and a single-phase inversion module which are commonly connected to a DC bus. The central control unit adjusts the output power of the multi-port flexible interconnection system and the control strategy of the single-phase inversion module in real time so as to realize flexible consumption of new energy and improvement of power supply stability. The system has the advantages of compatibility, cost effectiveness, new energy access and consumption, power supply reliability improvement, electric energy quality optimization, high adaptability and the like, and is suitable for upgrading and reconstruction of newly-built railway lines and existing railway lines.

The invention provides a traction power supply system control method based on multi-objective optimization, and the method comprises the following steps: S1, determining an initial control variable of a traction system, the initial control variable comprising converter power of an alpha power supply side and a beta power supply side of the traction power supply system and train braking resistor dissipation power of the alpha power supply side, the initial control variable is used as input to construct a regenerative braking energy MPC prediction model; s2, predicting a state variable of a next moment based on a regenerative braking energy MPC prediction model, wherein the state variable comprises output power of a traction substation, total dissipation power of a brake resistor, output power of an energy storage system and a charge state of the energy storage system; and S3, constructing a multi-objective optimization function based on the state variable at the next moment, converting the multi-objective optimization function into a quadratic programming form for solving to obtain a control variable sequence, and taking a first item of the control variable sequence as control input to control the traction power supply system to work.

The present invention provides a rigid catenary disconnection device, belonging to the technical field of catenary. It solves the problem that the existing disconnection device cannot close large-width vertical rotating flood control doors. This rigid catenary includes a fixedly arranged first busbar, a second busbar, a third busbar and a fourth busbar. The third busbar and the fourth busbar are located between the first busbar and the second busbar. The disconnection device includes a mounting post, a cantilever capable of rotating around the mounting post, and a switching clamp arranged on the cantilever. When the switching clamp is closed, it can clamp the third busbar and the fourth busbar to connect the third busbar and the fourth busbar. When the switching clamp is opened, the third busbar can rotate around the first busbar under the action of its own gravity, and the fourth busbar can rotate around the second busbar under the action of its own gravity. This disconnection device has the advantage that after the rigid catenary is disconnected, enough distance can be vacated to enable the large flood control door to be closed.

The invention relates to a hybrid energy storage control method for an urban rail transit energy router. The method comprises the following steps: S1, carrying out topological structure design and system compatibility configuration on the energy router; s2, impedance modeling and frequency division power distribution of the hybrid energy storage system are carried out; s3, fuzzy controller design and super capacitor SOC dynamic management are carried out; s4, carrying out membership function optimization and fuzzy control parameter setting; s5, multi-mode cooperative control and system operation optimization are carried out; according to the structure of the energy router and the power utilization characteristics of the rail transit system, working modes are divided, the working state of the system is optimized, and the system is kept in a reasonable working state. The method can effectively improve the utilization rate of energy and prolong the service life of the system.

The invention relates to the technical field of alternating current electrified railway power supply, in particular to a negative sequence treatment method and system for an electrified railway traction substation, and the system comprises a step-down isolation transformer and an SVG compensation subsystem. The primary side of the step-down isolation transformer is used for being connected with the high-voltage wire inlet side of a three-phase power grid of a traction substation, and three-phase medium-voltage electricity is formed after step-down isolation and connected to a three-phase medium-voltage bus. The SVG compensation subsystem is used for being connected to a three-phase medium-voltage bus; the SVG compensation subsystem is used for outputting negative sequence compensation current; the direction of the negative-sequence compensation current is opposite to that of the negative-sequence current generated by the traction load, and the negative-sequence compensation current and the load current generated by the traction load counteract each other, so that the treatment of the negative-sequence current is realized.

An apparatus for use in a power delivery system, the apparatus comprising: a DC circuit breaker having first and second terminals and configured to automatically switch from a closed state to an open state during an overcurrent condition; a disconnector switch in series with the DC circuit breaker, the disconnector switch having a first terminal for connecting to a first polarity terminal of a DC power supply, a second terminal for connecting to a second polarity terminal of the DC power supply and a common terminal connected to the first terminal of the DC circuit breaker, the disconnector switch having at least a first position in which the first terminal is connected to the common terminal and a second position in which the second terminal is connected to the common terminal; and an interlock mechanism coupled to the DC circuit breaker and the disconnector switch, the interlock mechanism configured to disable the DC circuit breaker from automatically switching from the closed state to the open state during the overcurrent condition when the disconnector switch is in the second position.

The invention provides a voltage fluctuation suppression method and device for a subway direct-current power supply system, and the method comprises the steps: obtaining the voltage amplitude change information of the subway direct-current power supply system at different sampling moments, and determining a real-time voltage fluctuation sequence and the operation state characteristics of each power supply node according to the voltage amplitude change information; space-time correlation mapping processing is carried out on the real-time voltage fluctuation sequence and the operation state features, a fluctuation correlation feature set is generated, and the fluctuation correlation feature set comprises voltage fluctuation space-time propagation path features and inter-node coupling influence features; calling a pre-trained fluctuation suppression decision model to perform dynamic suppression strategy generation processing on the fluctuation association feature set to obtain a voltage regulation parameter sequence for each power supply node; according to the voltage regulation parameter sequence and the operation state characteristics of the power supply nodes, generating a node-coordinated fluctuation suppression execution instruction set; and according to the fluctuation suppression execution instruction set, triggering voltage regulation operation of each power supply node to suppress voltage fluctuation.

The invention discloses a power supply mode control method and control device for a dual-source locomotive, and the power supply mode control method comprises the steps: controlling the locomotive to enter an automatic power supply mode, and then obtaining a front networking signal and an upper networking signal sent by an automatic driving system of the locomotive in real time; wherein the front network signal is used for describing whether a contact network exists at a first preset distance in front of the running of the locomotive, and the upper network signal is used for describing whether the contact network exists above the current position of the locomotive; if the front network signal is the high-level signal and the upper network signal is the high-level signal, controlling the locomotive to enter an automatic pantograph-catenary mode; if the front network signal is the low-level signal or the upper network signal is the low-level signal, the locomotive is controlled to enter an automatic battery mode. According to the invention, automatic switching between the pantograph-catenary mode and the battery mode is realized, the operation steps of workers are reduced, the probability of machine damage accidents during manual switching of the modes is effectively reduced, and meanwhile, the energy utilization rate is improved.

The invention discloses an electric energy dispatching method based on railway mobile energy storage, and relates to the field of rail transit power grids. The method comprises the following steps: acquiring an energy change parameter of each node in a power grid, wherein the energy change parameter comprises at least one of an energy injection amount and an energy output amount; according to the respective energy change parameters of the two adjacent nodes, energy interaction parameters between the two adjacent nodes are determined, so that the regional energy balance degree of the two adjacent nodes is obtained, and the larger the energy interaction parameters are, the higher the regional energy balance degree is; determining the regional frequency deviation degree of each node according to the energy injection amount and the energy output amount of each node; and based on the regional energy balance degree and the regional frequency deviation degree, obtaining starting and ending points of electric energy transportation in the power grid. The method can effectively improve the adaptability and stability of the power grid to renewable energy power generation volatility, and enhance the reliability of power supply.

The invention discloses a distributed cooperative voltage control method for a hybrid flexible traction substation group, and aims at solving the problems of output voltage cooperation, no-load circulating current suppression and multi-substation load distribution during networking operation of a plurality of hybrid flexible traction substations (HFTSS). Rapid synchronization of output voltage phases of the substations is achieved by introducing an average consistency algorithm, and nearby distribution of train loads among the traction substations is achieved by combining self-adaptive virtual impedance. According to the method, the capacity of the hybrid flexible traction substation for coping with the dynamic change of the external power grid voltage phase can be effectively enhanced, the loss of a contact network is reduced, the regenerative braking energy utilization efficiency is improved, and a feasible path is provided for large-scale application of a low-cost hybrid flexible traction power supply system and improvement of a cooperative control technology system.

The method is applied to the fields of train regenerative braking energy utilization, stray current and rail potential treatment and the like in electrified rail transit, especially urban rail transit. The invention provides a direct-current traction power supply system capable of reducing the energy storage capacity of a super capacitor of urban rail transit, which is combined with a super capacitor energy storage device of the urban rail transit and supplies power to a power electronic device for treating stray current and rail potential by utilizing regenerative braking energy of a train. The super-capacitor energy storage device has the following advantages that on one hand, the energy storage capacity of the super-capacitor bank in the super-capacitor energy storage device between train braking and traction can be reduced, and the utilization efficiency of regenerative braking energy stored by the super-capacitor bank is improved; on the other hand, the problems of stray current, rail potential and the like in the system can be solved from the source, and the power supply distance of a traction substation is remarkably increased. Therefore, the direct-current traction power supply system is of great significance to green and safe operation of urban rail transit.

The invention discloses a protection method and device for a train split-phase region and a storage medium, and the method comprises the steps: obtaining a split-phase region protection starting point and a split-phase region protection end point, and building a split-phase region protection region according to the split-phase region protection starting point and the split-phase region protection end point; a first movement authorization terminal point of the train is obtained, and when the first movement authorization terminal point intrudes into the split-phase zone protection area, the starting point of the split-phase zone protection area is determined as a second movement authorization terminal point; and performing split-phase zone protection parking operation according to the second movement authorization terminal point. Therefore, by establishing the split-phase zone protection area in advance and combining the moving authorization terminal point of the train, the split-phase zone protection parking operation is accurately executed, and therefore the situation that the train is accidentally parked in the split-phase zone is effectively avoided, safer, more efficient and more reliable train operation management is achieved, and the train operation efficiency is improved.

The application provides a voltage fluctuation suppression method and device for a subway direct-current power supply system, comprising: obtaining voltage amplitude change information of the subway direct-current power supply system at different sampling moments, determining a real-time voltage fluctuation sequence and an operating state feature of each power supply node according to the voltage amplitude change information; performing space-time correlation mapping processing on the real-time voltage fluctuation sequence and the operating state feature to generate a fluctuation correlation feature set, wherein the fluctuation correlation feature set comprises a space-time propagation path feature of voltage fluctuation and a coupling influence feature between nodes; calling a pre-trained fluctuation suppression decision model to perform dynamic suppression strategy generation processing on the fluctuation correlation feature set to obtain a voltage regulation parameter sequence for each power supply node; generating a node-coordinated fluctuation suppression execution instruction set according to the voltage regulation parameter sequence and the operating state feature of each power supply node; and triggering voltage regulation operations of each power supply node according to the fluctuation suppression execution instruction set to suppress voltage fluctuation.

The invention provides a configuration method for reconstructing a self-healing function of a traction power supply system, which adopts a hierarchical and hierarchical configuration mode, expands a mode flow step by step by a configuration tool according to an optional power supply network configuration scheme, intelligently selects an applicable action flow according to the current network condition during engineering application, and improves the self-healing function of the traction power supply system. The configuration of reconstructing the self-healing function is simply and quickly completed. According to the method, all action steps involved in the reconstruction self-healing process are switched, and meanwhile, switch attributes such as switch types, action time and synchronous actions are set for each switch, so that the reconstruction self-healing function can be completed more accurately, effectively and quickly. According to the method, real-time reconstruction self-healing process confirmation and modification can be provided, under the condition that a device is not restarted, the mode process is modified through a real-time human-computer interaction interface, the modified and confirmed reconstruction self-healing mode process is sent to a dispatching end for confirmation, and various unexpected field conditions can be flexibly coped with.

The invention discloses a dynamic multi-interval charging and discharging voltage threshold value adjusting method based on deep reinforcement learning by adopting a multi-train super-capacitor energy storage system aiming at the problem of traction network voltage safety and stability caused by high power and high energy of an urban rail transit multi-train energy storage system circuit model. According to a super-capacitor double-cascade control part of charge and discharge voltage thresholds, the charge and discharge voltage thresholds of a multi-train super-capacitor energy storage system (SC-ESSs) are dynamically adjusted according to intervals in real time by adopting a deep reinforcement learning (Soft Actor-Critic SAC) algorithm, and online strategy updating and sequential decision execution are further designed, so that the online strategy updating and sequential decision execution are realized. On-line strategy learning and optimization are carried out by combining'trial and error 'and'feedback' mechanisms of the agent, so that the training efficiency and optimization accuracy of the agent are improved, the energy-saving and voltage-stabilizing characteristics of the traction network are effectively improved, the charging and discharging current of the ground super capacitor can be stably controlled, the over-charging and over-discharging phenomena are prevented, and the service life of an energy storage element of the super capacitor is prolonged.

The embodiment of the invention provides a medium voltage holding control method and device for train neutral section passing and a storage medium. The method comprises the steps that in the neutral section passing process of a to-be-controlled train, the first real-time speed of the to-be-controlled train is obtained; according to the first real-time speed, a medium-voltage maintaining control strategy corresponding to the train to be controlled is determined; if the medium-voltage holding control strategy corresponding to the train to be controlled is a low-speed neutral-section passing medium-voltage holding control strategy, auxiliary load shedding control is started, and after the auxiliary load shedding control succeeds, the control state of the traction converter is controlled according to the low-speed neutral-section passing medium-voltage holding control strategy; if the medium-voltage holding control strategy corresponding to the train to be controlled is the high-speed passing neutral section medium-voltage holding control strategy, the control state of the traction converter is controlled according to the high-speed passing neutral section medium-voltage holding control strategy. According to the method, the traction recovery time after the train goes out of the split phase is effectively shortened, and forced stopping caused by no traction output due to too low speed is avoided.

The vehicle has an electric traction chain (3) for supplying drive torque to the wheels, a generator set (6) configured to generate a first supply voltage and mechanically disconnected from the wheels in all operating states, a battery storage assembly (21) configured to generate a second supply voltage, and an energy management system (20, 40) having a control unit that implements operating states of the vehicle including: (i) powering the electric traction chain (3) with the first supply voltage, (ii) powering the electric traction chain (3) with the second supply voltage, (iii) charging the storage assembly with a network voltage external to the vehicle and coming from a catenary (104), (iv) charging the storage assembly with the first supply voltage, and (v) charging the storage assembly with recovered voltage generated by the traction chain acting as a generator.

The invention discloses a two-phase input coordination control method and system for a hybrid through traction power supply device. The method comprises the following steps: acquiring alternating-current side voltage and current and direct-current side voltage of each group of two-phase input ports in the device in real time; obtaining an active reference instruction of each output port according to the DC side voltage; performing single-phase dq conversion based on a virtual axis according to the alternating current side voltage and current to obtain dq axis current components of each group of two-phase input ports; obtaining active and reactive current reference instructions of each group of two-phase input ports according to the active reference instruction and a first condition; pWM modulation is carried out according to the dq-axis current component and the active and reactive current reference instruction, and PWM instructions of each group of two-phase input ports are obtained; and continuously obtaining a PWM instruction and driving the device according to the PWM instruction.

The invention relates to a converter grid-connected current harmonic suppression method and device for a traction power supply system, and is applied to the technical field of rail transit traction power supply. The method comprises the following steps: acquiring traction power supply electrical parameter information and grid-connected output current information of each slave controller in a grid-connected converter; determining a grid-connected reference current according to the traction power supply electrical parameter information; and based on the grid-connected reference current, performing harmonic suppression and phase lead compensation on the grid-connected output current information by utilizing closed-loop control of multiple quasi-proportional resonance based on multiple phase lead compensation, and determining the current grid-connected output current. Through multiple quasi-proportional resonance control, the harmonic content of steady-state current output by the grid-connected converter can be suppressed; and in order to avoid control time delay caused by multiple quasi-proportional resonance control, the phase is subjected to lead compensation, so that the obtained current grid-connected output current meets the response speed requirement, and the electric energy quality of the grid-connected current is improved. Therefore, the operation stability of the traction power supply system can be improved.

The invention discloses an energy storage cophase power supply system based on a V-connection traction transformer, a control method and a storage medium, and belongs to the technical field of electrified railway power supply. The energy storage in-phase power supply system comprises a V-connection traction transformer, three single-phase compensation devices, an energy storage device and a coordination control device. The primary side of the V-connection traction transformer is connected with a three-phase power supply, and any port of the secondary side is connected with a traction load; aC ends of the three single-phase compensation devices are respectively connected to different ports of the secondary side, and DC ends are connected in parallel to a DC bus; the energy storage device is also connected in parallel with the DC bus. The coordination control device collects current and voltage signals and controls operation of the devices. The system has the functions of energy storage and in-phase power supply, and solves the problems of large traction load fluctuation of a traditional electrified railway traction substation, power return caused by train regenerative braking, train over-electricity split-phase stall and electric energy quality management.

The utility model relates to a combined type carrier cable seat which comprises a connecting base, a connecting double-lug and a cable supporting clamp, one side of the connecting base is hinged to one side of the connecting double-lug, the other side of the connecting base is fixed to the other side of the connecting double-lug through a fastening bolt, and a clamping block is arranged in the center of the outer arc face of the connecting base. A clamping hole corresponding to the clamping block in shape is formed in the center of the wire supporting clamp, the connecting base is clamped into the clamping hole through the clamping block and then rotates by 90 degrees to be fixedly connected with the wire supporting clamp, the carrier cable is arranged in the wire supporting clamp, and a pressing plate for pressing the carrier cable is fixedly connected to the wire supporting clamp. The connecting base and the connecting double lugs are fixedly connected through the fastening bolts, the number of types of carrier cable seats can be reduced, and the connecting strength and reliability of the assembly are improved; the die forging process reduces the existence of shrinkage cavities and segregation of the part blank, and is beneficial to improving the mechanical property of the product; the clamping blocks are clamped into the clamping holes to achieve fixed connection between the connecting base and the wire supporting clamp, the electric arc radiation phenomenon in the use process of the contact network can be reduced, and stable operation of the contact network is guaranteed.

The present invention discloses a main wiring structure of a hub traction substation, which includes two external power supplies and two groups of traction transformers. It also includes a switching unit, several feedback lines, and two independently arranged busbars. One group of busbars is powered by one power supply, and the other group of busbars is powered by the other power supply. Each group of busbars is configured with the same number of feeder lines to form two independent power supply devices that are physically isolated and electrically separated from each other; the feeder lines all pass through the switching unit (7) and the corresponding switches (8); switches (8) are provided on all the feeder lines to achieve switching between the two groups of power supply devices through the switching of the switches. The main wiring structure of the hub traction substation of the present invention sets two mutually independent power supply devices. Due to the achievement of physical isolation and electrical separation, when one group of devices fails or is struck by lightning, the other group of devices can be unaffected and quickly put into operation, thus restoring normal power supply and improving power supply reliability.

The embodiment of the invention provides a power supply optimization method and device for a railway traction system, and the method comprises the steps: inputting a current voltage fluctuation parameter of the railway traction system into a pre-constructed fluctuation prediction model, and obtaining a corresponding expected voltage fluctuation parameter, the fluctuation prediction model comprises a linear regression model or a first neural network model, and the current voltage fluctuation parameter comprises a current voltage parameter and a previous fluctuation voltage parameter; determining a control parameter of the inverter of the railway traction system according to the current voltage fluctuation parameter and the expected voltage fluctuation parameter; controlling the inverter to adjust the corresponding output voltage according to the control parameter until the deviation value between the current voltage fluctuation parameter and the expected voltage fluctuation parameter is within a preset deviation range; according to the method, the problem of power instability caused by power grid voltage fluctuation in the operation process of the high-speed train can be solved, and the safety and reliability of train operation are guaranteed.

The invention provides a rail transit overhead line system double-carrier-cable dropper wire clamp, and relates to the technical field of rail transit, the rail transit overhead line system double-carrier-cable dropper wire clamp comprises a wire clamp main piece, a wire clamp auxiliary piece and a fixing device, the wire clamp main piece is arranged below a carrier cable; the auxiliary wire clamp piece is arranged below the carrier cable, the auxiliary wire clamp piece and the main wire clamp piece are arranged on the same horizontal line, and the auxiliary wire clamp piece is fixedly connected with the main wire clamp piece; the fixing device is arranged on the wire clamp main piece and the wire clamp auxiliary piece, the fixing device is used for being fixedly connected with a carrier cable, the wire clamp main piece and the wire clamp auxiliary piece are arranged and fixedly connected, the mode that in the prior art, a thread pair is adopted for connection and fixation is replaced, and the maintenance frequency is effectively reduced.

The invention discloses a locomotive electrical system and a locomotive power supply control method, and the locomotive electrical system is characterized in that the high-voltage input end of a traction transformer is electrically connected with a locomotive contact net through the rising of a pantograph, or is electrically disconnected with the locomotive contact net through the falling of the pantograph; the input end of the four-quadrant rectifier module is connected with the low-voltage output end of the traction transformer; the auxiliary load module, the power battery module and the traction module are respectively connected with the output end of the at least one four-quadrant rectification module; the power battery module is used for storing energy and supplying power to the locomotive; the traction module is used for traction locomotive driving and / or kinetic energy recovery. The invention provides a locomotive electrical system. An auxiliary load module, a power battery module and a traction module are connected to the output end of a four-quadrant rectification module. The auxiliary load module, the power battery module and the traction module operate independently so that a charging strategy can be controlled conveniently, and charging of a power battery of a locomotive electrical system can be achieved when a locomotive operates.

The invention relates to an urban rail transit flexible direct current traction power supply method based on an energy router. The method comprises the following steps: constructing each structured energy intention corresponding to a train control terminal according to train running state data corresponding to the train control terminal; respectively analyzing space-time information in each structured energy intention to obtain an intention perception map corresponding to the train control terminal; performing energy efficiency analysis on each lattice point in the intention perception map to obtain a lattice point efficiency analysis structure data set; analyzing the power supply behavior of each train corresponding to the train control terminal according to the lattice point efficiency analysis structure data set to obtain power supply behavior execution data corresponding to each train; the power supply behavior execution data is used for carrying out flexible direct-current traction power supply on the train. By adopting the method, the sensing precision and the regulation and control capability of the power supply behavior of the train can be effectively improved.

The present application relates to a method, system, equipment, and medium for monitoring the status of a railway traction substation. The monitoring method includes: obtaining real-time monitoring data of equipment in the railway traction substation; preprocessing the real-time monitoring data to obtain a preprocessed monitoring data set and performing protocol identification, and converting the heterogeneous data in the monitoring data set into structured data based on a preset protocol template library; extracting the time-frequency domain characteristic parameters of the equipment based on the structured data and constructing a multi-dimensional feature matrix; inputting the multi-dimensional feature matrix into a pre-trained hybrid diagnostic model to generate an equipment health score and a fault probability value; generating an early warning instruction based on the health score and the fault probability value in combination with a dynamic threshold algorithm; and generating a priority maintenance strategy based on the early warning instruction and the equipment maintenance resource constraints through a maintenance strategy optimization model. The present application realizes accurate perception and intelligent decision-making of equipment status in a multi-source heterogeneous data environment.

To obtain a power control unit that enables suitable power utilization according to a situation of equipment included in a railway system.SOLUTION: A power control unit 21 comprises: a data acquisition part 22 that acquires status data from at least one managed object among an electrical feeding system including equipment for supplying electric power to an electric train, the electric train, and station equipment; a calculation part 24 that calculates control parameters for controlling electric power in at least one controlled object among the electrical feeding system, the electric train, and the station equipment on the basis of status data of a managed object different from the controlled object; and a transmission processing part 25 that transmits the calculated control parameters to the controlled object.SELECTED DRAWING: Figure 2

Embodiments include techniques for automatically restarting a voltage foldback circuit, the techniques include operating a circuit, and detecting a condition of the circuit. The techniques also include performing a foldback operation based at least in part on the condition of the circuit, subsequently detecting the condition of the circuit. The techniques include initiating a timer of the circuit based at least in part on the subsequent detection of the circuit, and returning the circuit to normal operation based on the timer.