66results about "Generation protection through control" patented technology

The invention discloses an excitation carbon brush and collecting ring digital monitoring operation and maintenance system, method and device and a medium, and belongs to the technical field of power equipment monitoring, and the method comprises the steps: obtaining the real-time current data of a plurality of carbon brushes, and determining the deviation degree of each carbon brush current relative to a reference current; according to the generator operation condition parameters, determining a deviation threshold value used for judging carbon brush current abnormity; when it is detected that the current deviation degree of the target carbon brush exceeds a deviation threshold value, an adjustment control signal is generated; and responding to the adjustment control signal, performing mechanical stimulation operation on the target carbon brush, and changing the contact state of the target carbon brush and the collector ring. Automatic balance adjustment of the current of the carbon brush is realized through mechanical stimulation operation, and the service life of the carbon brush is prolonged.

A power converter system includes an asynchronous induction generator electrically coupled to an inverter / converter / controller (ICC). The ICC is coupleable to an electrical load. The ICC can include an AC-DC converter and a DC-DC converter. The DC-DC converter is configured to operate at a duty cycle substantially equal to 1 in a first operating mode. In the event of a short-circuit fault in the electrical load, the DC-DC converter is configured to operate at a duty cycle less than 1 in a second operating mode.

A distributed multi-phase generator includes a plurality of generator subsystems, with each generator subsystem including a respective processor and rotor. The plurality of generator subsystems is configured to generate a combined voltage output that is in one of a plurality of different phases. The plurality of generator subsystems are configured to communicate operating parameters to each other, and in some embodiments, can control another generator subsystem or compensate for changes in operation of another generator subsystem (including faults). As part of dynamic generator operation, each generator subsystem can adjust its field angle modulation scheme based on feedback received from other generator subsystems as well as its own operation.

A motor device prevents electrolytic corrosion of a bearing. The motor device is mounted on a vehicle and has a stator installed in a housing and provided with a concentrated winding coil, a rotor housed in the center of the stator and provided with a permanent magnet, a bearing installed in the housing and supporting a rotating shaft of the rotor, an inverter provided between the stator and a power storage body and controlling an energization state of the concentrated winding coil, and an energization control section that outputs a control signal to the inverter and executes field weakening control that generates a magnetic flux of the concentrated winding coil in a direction to weaken a magnetic flux of the permanent magnet. The energization control section executes the field weakening control to make a potential difference between the housing and the rotating shaft, i.e., shaft voltage Va1, lower than a withstand voltage Vb1 of the bearing when a motor revolution number Nm is greater than a threshold value Nx.

A power generation device (1) includes: a power generator (10), a power conversion circuit (21), a first interruption circuit (23), a second interruption circuit (24), a first monitoring circuit (25) which monitors an output current flowing from the power generator (10) to the power conversion circuit (21) and outputs a first interruption signal when an absolute value of the output current exceeds a first predetermined value, and a second monitoring circuit (26) which monitors a total value of output voltages of respective phases of the power generator (10) and outputs a second interruption signal when an absolute value of the total value exceeds a second predetermined value. A first interruption circuit (23) electrically interrupts a connection between the power generator (10) and the power conversion circuit (21) in accordance with the output of the first or second interruption signal, and the second interruption circuit (24) electrically interrupts the connection between the three-phase coils (Lu, Lv, Lw) and the neutral point (N) in accordance with the output of the first or second interruption signal.

The invention discloses a generator rectifying device which comprises a rectifying device and a generator, the rectifying device comprises a rectifying module, a centrifugal fan and a shaft connector, the centrifugal fan comprises an impeller, an impeller shaft, a first end plate and a second end plate, and the first end plate and the second end plate are connected through a plurality of supporting columns to form a centrifugal fan shell. The impeller is coaxially installed between the first end plate and the second end plate, the impeller shaft is coaxially and integrally arranged on the side, close to the first end plate, of the impeller, and the end, away from the impeller, of the impeller shaft penetrates through the first end plate and is coaxially connected with a generator rotor rotating shaft through a shaft connector. The two rectification modules are installed on the side, away from the first end plate, of the second end plate of the centrifugal fan in a mirroring mode, and when a rotor of the generator rotates, the centrifugal fan conducts heat dissipation on the generator and the rectification modules at the same time. The centrifugal fan is arranged on the rectifier module, so that the aim of performing air-cooling heat dissipation on the rectifier module and the generator at the same time is fulfilled.

An aircraft turbine engine including at least a propulsion shaft and an electric motor. A rotor is rigidly connected to the propulsion shaft. The electric motor includes at least three power channels, a control device designed to determine a control parameter for each power channel on the basis of a control command, and a correction device designed to correct a precession movement of the rotor relative to the stator. The correction device being designed to determine the control command of the control device from a setpoint command and a precession level. The control command being designed to generate a global magnetic force opposing the precession movement of the rotor so as to damp said movement.

The invention discloses a double-fed wind turbine generator network-related performance optimization method adaptive to high-power fault impact. The method comprises the following steps: step 1, constructing a multi-sequence domain model of a double-fed wind turbine generator under high-power fault impact; 2, constructing a double-layer optimization model taking the minimum de-excitation time constant as an upper layer and the minimum voltage unbalance degree as a lower layer; and step 3, solving the multi-sequence-domain model based on the double-layer optimization model to obtain rotor de-excitation and positive and negative sequence current instructions. According to the method, rotor multi-sequence domain finger current instructions can be coordinated on the premise that stress constraint is met, the unbalanced voltage suppression capability of the doubly-fed fan is remarkably improved while rapid de-excitation is considered, and a reference is provided for improving the grid-related performance of the doubly-fed fan.

A safety module for an inverter of a motor vehicle. The inverter including at least two power circuits. The safety module including a control unit and at least two safety switches, each safety switch being associated with a power circuit and being connected between the power circuit and a point referred to as the “measurement” point. The control unit being capable of controlling each safety switch and being configured to detect a closing malfunction of a safety switch if: a) a closing command has been sent to the safety switch, the other safety switches being open, b) and the voltage at the measurement point is negative.

The invention relates to a variable-speed pumped storage unit stator grounding and rotor grounding fault arc extinction method and device based on machine end injection. The method comprises the following steps: acquiring and determining a phase corresponding to a minimum actual voltage in three phases of the variable-speed pumped storage unit as a fault phase under the condition that a ground fault of the variable-speed pumped storage unit is monitored, and acquiring a first electric signal under the condition that the ground fault is a stator ground fault; according to the first electric signal, a first arc extinction compensation amount is determined, and the first arc extinction compensation amount is injected into a stator winding from the machine end of the variable-speed pumped storage unit, so that effective arc extinction of a stator grounding fault is achieved; and when the grounding fault is the rotor grounding fault, acquiring an injection signal and a second electric signal, then determining a second arc extinction compensation amount according to the injection signal, the fault phase and the second electric signal, and injecting the second arc extinction compensation amount to the rotor winding from the machine end of the variable-speed pumped storage unit so as to realize effective arc extinction of the rotor grounding fault.

The invention provides a control method for reactive power output of a converter, which comprises the following steps: an online generator set outputs reactive power according to a target reactive power value of power grid dispatching, if the temperature of the online generator set exceeds a first temperature value, an offline generator set outputs reactive power and shares reactive power demand, and if the temperature of the online generator set does not exceed the first temperature value, the offline generator set outputs reactive power and shares reactive power demand; and when the target reactive power demand value of the on-line unit is greater than the reactive power threshold of the machine-side converter, the grid-side converter of the on-line unit outputs reactive power and bears part of the reactive power demand, so that the load of the machine-side converter can be reduced while the reactive power demand of power grid dispatching is met, and the reactive power generation capability of the converter is improved.

A method for operating a multi-stage bridge power converter in an electrical power system includes connecting multiple phases of the power converter to a common terminal on the DC side of the power converter to effectively make the multiple phases equal at a common potential. The method may further include fault monitoring of multiple devices of the power converter via a controller. Upon detecting a fault in one or more of the multiple devices, the method includes activating one or more protective devices of the power converter via the controller to prevent further faults in the remaining devices by diverting energy from the remaining devices.

The invention discloses a generator torsional vibration protection action control method and system based on fuzzy control, and relates to the technical field of generator torsional vibration protection. Respectively inputting the torsional vibration sensing signal into a judgment path with fuzzy reasoning capability and a judgment path adopting a fixed threshold value criterion, synchronously carrying out data processing on the two judgment paths, and recording a historical input value and a corresponding judgment result in an operation period to form a data structure for state inheritance; in a continuous judgment period, results of the two judgment paths are compared and analyzed through logic criteria, if a switching triggering condition is met, master control logic switching is executed between the two judgment paths, and a signal value and a judgment state stored in an original master control path are converted into an initialization input state required by a new path; and introducing a preset time sequence delay processing and nonlinear function transition processing process, and carrying out time slow change adjustment on the action amplitude.

A switching arrangement (30) for arc quenching in a wind turbine (1), the wind turbine (1) having a generator (11) and a machine-side converter (12). The switching arrangement (30) comprises a set of switches (34) electrically coupled to power lines (13) of a connection (13) between the generator (11) and the machine-side converter (12). At least one power line (36, 38) of the connection (13) is permanently connected to multiple switches (34) of the switching arrangement (30).

A method for isolating faults in an electrical power system connected to a power grid includes dividing the electrical power system into a plurality of power modules each including a plurality of electrical power subsystems and a substation. Each of the electrical power subsystems defines a stator power path and a converter power path for providing power to the power grid and having a partial power transformer. The method also includes coupling each of the power modules to the power grid via a primary electrical line. Further, the method includes monitoring the electrical power system for faults. In response to detecting a fault in one of the power modules, the method includes isolating the fault to the power module experiencing the fault. In contrast, if the fault is detected in the primary electrical line or the power grid, the method includes tripping the electrical power system.

A method for detecting an electrical fault in a stator of an electrical machine, wherein the stator comprises a plurality of sets of windings, wherein each set of windings is assigned to a respective phase of the electrical machine, the method comprising the steps of determining a respective current: first, between a subset of one of the sets of windings and a different further subset of the same set of windings, and / or second, between a subset of one of the sets of windings and a neutral point, and / or third, between the neutral point and a further neutral point or at least a common neutral point connected to the neutral point and the further neutral point, evaluating a fault condition, wherein a fulfillment of the fault condition depends on the respective determined current, and outputting a fault signal to a person and / or a device when the fault condition is fulfilled.

A voltage regulator for a generator having a dynamic voltage-to-frequency (V / F) ratio includes a memory, a voltage calculator, and a selection module. The memory is configured to store a plurality of voltage-to-frequency curves for the generator. The voltage calculator is configured to receive data indicative of an output of the generator and to determine a resistance value from the output of the generator and to determine a voltage value from the output of the generator. The selection module is configured to select a voltage-to-frequency curve from the plurality of voltage-to-frequency curves responsive to the resistance value and to select a voltage-to-frequency ratio from the selected voltage-to-frequency curve responsive to the voltage value. An output regulation for the generator is determined responsive to the selected voltage-to-frequency ratio.

The invention relates to a system (0) for controlling a short-circuit current of an electrical network (3), comprising a power converter (2) controlled by a control system (4) and configured to rectify and regulate a voltage of an electric machine (1), the control system (4) comprising:-a synchronization unit (41); -a control unit (42) for controlling:-in an active short-circuit mode,-in a freewheeling mode,-by asynchronous pulse width modulation,-a regulation unit (43); in the event of a short circuit, the control system (4) controls the power converter (2) in order to supply a direct current equal to a predetermined value to the electrical network (3).

The invention is suitable for the technical field of torque control, and provides a torque control method, device and equipment of a wind generating set, the wind generating set comprises a converter and a generator, and the method comprises the steps that the current actual temperature of an IGBT module located in the converter and the current actual rotating speed of the generator are obtained; based on the corresponding relation between the actual temperature and the synchronous rotating speed interval, the current synchronous rotating speed interval is determined according to the current actual temperature; determining a corresponding current torque threshold value according to the current actual rotating speed based on a corresponding relation between the actual rotating speed and the torque threshold value in the current synchronous rotating speed interval; determining a target torque according to the current torque threshold value, so that the target torque of the generator is smaller than or equal to the current torque threshold value; and by controlling the alternating current device, the generator outputs the target torque. According to the invention, the technical problem that the reliable operation of the converter is affected due to the fact that the generator is easy to respond to large torque and the temperature of the IGBT module is too high when the generator operates near the synchronous rotating speed for a long time can be solved.

The invention discloses a fault distinguishing method of a generator and a protection device, and aims to solve the technical problem that it is difficult to accurately distinguish a voltage measurement loop fault and a bus system fault in the prior art. The fault distinguishing method comprises the steps that when it is judged that at least two paths of generator terminal voltage signals have faults, stator current characteristics of a generator are obtained, and whether the fault type is a voltage signal collection fault or a bus fault is judged based on whether a stator current absolute value in the stator current characteristics is abnormal or not. The protection device provided by the invention comprises corresponding function modules for executing the method. By introducing the stator current characteristics for judgment, the fault source can be accurately discriminated, and the protection system misoperation caused by the measurement loop fault is effectively prevented, so that the stability and the safety of the operation of the generator set are improved.

The application relates to a permanent magnet synchronous generator power generation voltage stabilization control strategy considering high-resistance contact faults, and steps are as follows: based on a dq rotating coordinate system, a permanent magnet synchronous generator mathematical model considering high-resistance contact faults is established; combined with the permanent magnet synchronous generator mathematical model considering high-resistance contact faults, an instantaneous power equation considering high-resistance contact faults is derived based on instantaneous power theory; combined with the instantaneous power equation considering high-resistance contact faults, a quantitative relationship between a direct-current terminal voltage double-frequency ripple and a cross-axis current is derived based on a small signal analysis method; combined with the quantitative relationship between the direct-current terminal voltage double-frequency ripple and the cross-axis current, a cross-axis current integral average compensation method is designed by taking the characteristic that a sine signal is integrated to zero in an integral period, and a compensated current is obtained to perform permanent magnet synchronous generator power generation voltage stabilization control. The application can inhibit the double-frequency ripple of the cross-axis current, and further reduce the double-frequency ripple of the direct-current terminal voltage, so that the purpose of voltage stabilization control is achieved.

The application relates to a variable-speed pumped storage unit stator ground fault and rotor ground fault arc extinguishing method and device based on machine end injection. In the case that a variable-speed pumped storage unit ground fault is monitored, the minimum actual voltage corresponding to the phase of the three phases of the variable-speed pumped storage unit is determined as a fault phase, a first electric signal is obtained in the case that the ground fault is a stator ground fault; then, according to the first electric signal, a first arc extinguishing compensation amount is determined, the first arc extinguishing compensation amount is injected from the machine end of the variable-speed pumped storage unit to the stator winding, so that effective arc extinguishing of the stator ground fault is realized; in the case that the ground fault is a rotor ground fault, an injection signal and a second electric signal are obtained, then, according to the injection signal, the fault phase and the second electric signal, a second arc extinguishing compensation amount is determined, the second arc extinguishing compensation amount is injected from the machine end of the variable-speed pumped storage unit to the rotor winding, so that effective arc extinguishing of the rotor ground fault is realized.

The invention relates to a protection method and system for shutdown of a medium-voltage generator based on reverse power, and the method comprises the steps: collecting three-phase voltage and current signals of the medium-voltage generator, and carrying out the preprocessing of the three-phase voltage and current signals; calculating real-time power based on the preprocessed three-phase voltage and current signals; judging whether the current medium-voltage generator generates reverse power or not based on a reverse power generation judgment rule and the real-time power, if so, calculating a reverse power quantized value, and comparing the reverse power quantized value with a reverse power grading threshold value to obtain a reverse power grade; executing corresponding shutdown protection measures of the medium-voltage generator based on the reverse power level; wherein the reverse power grading threshold value is optimized through reinforcement learning. The method is high in response speed, high in control precision, high in adaptability and suitable for safety protection requirements of the medium-voltage generator in multiple scenes.

A zero dynamic attack defense method for an automatic voltage regulator comprises the following steps: (1) system initialization and parameter configuration of the automatic voltage regulator; (2) candidate controller loading: configuring multiple groups of controller parameters capable of independently stabilizing the operation of the automatic voltage regulator in a control system in advance to form a candidate controller set; the candidate controllers are kept consistent in control structure, but control parameters are different, so that the corresponding closed-loop dynamic characteristics are different; (3) controller switching triggering and execution; and (4) performing operation and continuous defense after switching. According to the method, a dynamic switching mechanism of a controller is introduced in a system operation process, so that dynamic characteristics of a closed-loop system change along with time, and therefore, system uncertainty which is difficult for an attacker to accurately model and a fixed model assumption on which zero dynamic attack is destroyed to be established are actively constructed; on the premise of ensuring stable operation of the automatic voltage regulator, effective defense and suppression of zero dynamic attacks are realized.

The invention discloses a full-digital type 1E-level excitation control method and system, relates to the field of excitation control, and provides two connected control units, and the full-digital type 1E-level excitation control method comprises the following steps: the two control units circularly execute a main loop function after executing an initialization function respectively, and the main cycle function obtains the duty ratio of the driving signal according to the operation condition after the generator and the controlled control unit reach the excitation operation condition, and controls the main control unit to output excitation current to the excitation winding according to the driving signal. Under the constant voltage mode and the emergency working condition, based on the inertia principle, a voltage effective value is calculated according to the generator end voltage of the generator, and the duty ratio of the driving signal is calculated based on the voltage effective value; when the generator terminal voltage is collected, the sampling frequency is determined according to the generator terminal voltage frequency, so that the number of the sampled generator terminal voltage in one generator terminal voltage period is kept unchanged. According to the system, the reliability and the control precision of excitation control are improved.

The present invention relates to a system (0) for controlling the short-circuit current of an electrical network (3) comprising a power converter (2) controlled by a control system (4) and configured to rectify and regulate the voltage of the electrical machine (1), the control system (4) comprising: a synchronization unit (41); a control unit (42): - in active short-circuit mode, - in "freewheel" mode, - by asynchronous pulse width modulation, a regulation unit (43); so that in the event of a short circuit, the control system (4) controls the power converter (2) in order to deliver to the electrical network (3) a direct current equal to the predetermined value. Figure for abstract: Fig. 1

The application discloses a superconducting motor fault-tolerant control method and system considering quench faults, and belongs to the field of motor control. The method obtains a rotor flux estimation value by using a rotor flux estimation model according to a voltage control vector and a response current vector; if it is determined that a superconducting motor has occurred a quench fault, the method obtains a state current observation value of the superconducting motor under the quench fault by using a state current observation model according to the rotor flux estimation value and the response current vector; the method determines a voltage control vector of the superconducting motor under the quench fault by using a fault-tolerant control model according to a given current vector, the state current observation value of the superconducting motor under the quench fault and the response current vector; and the method applies the voltage control vector to the superconducting motor, so that the response current vector of the superconducting motor under the quench fault is equal to the given current vector. The application can effectively solve the robustness control problem of the superconducting motor when the quench fault occurs, and realizes stable operation of the superconducting motor.

A converter brake control method, comprising: in response to a wind turbine triggering a fault shutdown, controlling a converter to enter a brake load-reduction mode, wherein the brake load-reduction mode comprises: controlling a brake circuit of the converter to be closed, and controlling the torque at a rectification side of the converter to be reduced to a preset range; in response to meeting a brake load-reduction mode end condition, controlling the converter to exit the brake load-reduction mode; and controlling a safety chain of the converter to be disconnected. When a wind turbine triggers a fault shutdown, the energy consumption of a brake circuit of a converter is controlled and the torque of the converter is controlled to be reduced to a preset range, so that torque support of a shutdown process can be achieved, and the shutdown load of the wind turbine can be reduced. In addition, the present invention also relates to a controller and a wind turbine.

A system for a wind turbine, comprising a generator (28) connected to a power converter (30) by an electrical connection (32), a circuit breaker system (69) controlling the connection between the generator and the power converter through the electrical connection, and a sensor system (66) configured to sense operational parameters, wherein the generator is a permanent magnet generator. The system further comprises a protection system (61) interfaced to the circuit breaker system and the sensing system. The protection system is configured to determine an operational mode of the wind turbine (102) by monitoring at least two parameters of: the speed of the generator, the operational status of the power converter, and the operational status of the circuit breaker system, and defining an operational mode based on the monitored parameters, determine a parameter set comprising a plurality of operational parameters (104) based on the determined operational mode, and an associated set of expected values corresponding to the parameter set, wherein the determined parameter set includes generator voltage and generator speed, determine actual values corresponding to the determined parameter set (108), identify a fault condition in the event that the determined set of actual values of the operational parameters do not correspond to the determined set of expected values of the operational parameters, and implement a protection action based on the identified fault condition.

A distributed multi-phase generator includes a plurality of generator subsystems, with each generator subsystem including a respective processor and rotor. The plurality of generator subsystems is configured to generate a combined voltage output that is in one of a plurality of different phases. The plurality of generator subsystems are configured to communicate operating parameters to each other, and in some embodiments, can control another generator subsystem or compensate for changes in operation of another generator subsystem (including faults). As part of dynamic generator operation, each generator subsystem can adjust its field angle modulation scheme based on feedback received from other generator subsystems as well as its own operation.