209 results about "Power oscillation" patented technology

The invention relates to a charging pile AC / DC power dynamic cooperative regulation and control system, which belongs to the technical field of charging piles and comprises a power grid parameter acquisition module, a charging load characteristic analysis module, a coupling effect calculation module, a power distribution optimization module and a cooperative control execution module. The system can accurately distribute power to vehicles which really need and can be efficiently utilized, mutual interference between modules can be effectively restrained, power oscillation and cascading failures are avoided, the stability and reliability of the whole charging station under high-density operation are guaranteed, the robustness of the system is enhanced, and the service life of the charging station is prolonged. A dynamic and globally optimal balance point is found and maintained among three mutually restricted targets, namely, power deviation, coupling power and power grid constraint, by establishing and solving a multi-target optimization model containing power deviation, coupling power and power grid constraint, the stability of the multi-target optimization model is guaranteed, and the power grid safety is maintained, which cannot be achieved by any single-target or static-weight control strategy.

The invention discloses a laser wireless energy transfer dynamic MPPT control method based on an RL-PSO hybrid algorithm and a reconfigurable array system, and aims to solve the problems of power oscillation and mismatch loss caused by light spot offset of a photovoltaic array under laser dynamic irradiation. According to the method, reinforcement learning (RL) and particle swarm optimization (PSO) are fused, dynamic parameters such as the light spot moving speed and irradiance are sensed in real time through the RL, the inertia weight and learning factors of the PSO are adjusted in a self-adaptive mode, and collaborative optimization of global search and local tracking is achieved. According to the system level, a reconfigurable photovoltaic array is designed, and according to data of a light spot position sensor, battery series-parallel topology is dynamically adjusted through a switch matrix, and current matching is optimized. According to the method, double-loop control is adopted, wherein an outer-layer RL decision module dynamically switches PSO working modes according to the environment, and an inner-layer PSO module optimizes the working voltage. The system efficiency in a dynamic scene can be improved by 15%-30%, mismatch loss is reduced by 40% or above, and the method is suitable for unsteady-state energy supply scenes such as unmanned aerial vehicles and mobile robots.

The invention relates to the technical field of virtual impedance self-adaptive control of energy storage converters, in particular to a virtual impedance self-adaptive control method of a grid-forming type energy storage converter, which comprises the following steps of: acquiring three-phase voltage and current of a grid-connected point in real time; performing phase-locked loop processing and coordinate transformation to obtain a d-axis voltage, a q-axis voltage and a current under a synchronous rotating coordinate system; calculating instantaneous power, and obtaining active power and reactive power; virtual resistance and virtual inductance are calculated according to power fluctuation through an adaptive algorithm; the virtual impedance equation generates a voltage drop compensation signal; and superposing the compensation signal and the reference voltage to generate a new modulation wave, and inputting the new modulation wave into the pulse width modulation module to realize power oscillation suppression and stable operation. According to the method, the problems between damping enhancement and loss reduction in network construction type control are solved, the dynamic and steady-state performance of the converter is improved, and a key technical support is provided for large-scale and high-reliability application of the network construction type energy storage converter in a novel power system.

The invention relates to the technical field of energy storage systems, in particular to a symmetric / asymmetric fault ride-through control method for a network-forming type energy storage converter, which comprises the following steps of fault detection and classification, adaptive control target decision and multi-mode unified control. According to the method, adaptive and intelligent fault ride-through is realized, the control accuracy and efficiency are improved, the adaptability and robustness of the energy storage system in different power grid fault scenes are enhanced, the center of gravity is dynamically adjusted and controlled according to the charge state of the energy storage system or the received power grid dispatching instruction, the maximum utilization of system resources is realized, and the power grid fault ride-through efficiency is improved. The voltage and frequency support is provided for the power grid, the response speed is far higher than that of traditional deviation adjustment, the voltage support effect at the moment of a fault is greatly improved, sudden change of power and current is effectively prevented, secondary impact on the recovered power grid caused by off-grid of the converter or power oscillation is avoided, and the friendliness of network forming equipment is embodied.

The invention provides a virtual inertia adaptive control method, device and system, and relates to the technical field of inverter system control. The method comprises the following steps: calculating a reference current value according to a power reference value and an actual output voltage; calculating a current deviation value according to the reference current value and the actual output current value; outputting the current deviation value to an adaptive resonance controller to obtain a compensation control voltage signal; inputting the compensation control signal to an AHO virtual oscillator to obtain a reference value of the output voltage of the inverter; and controlling the output of the three-phase inverter circuit according to the reference value of the inverter output voltage. Wherein the adaptive resonance controller carries out adaptive control through the proportional parameter and the proportional resonance inertial parameter. The virtual inertia output can be dynamically adjusted according to the real-time requirement of the system, the overshoot phenomenon caused by power oscillation is effectively suppressed while the frequency stability is met, and the capacity of the system for resisting sudden load change and frequency disturbance is enhanced.

The invention discloses an active and reactive comprehensive oscillation quantity minimization cooperative control method under a current constraint condition, and the method comprises the steps: analyzing an inverter side current converter in a power grid voltage imbalance state, and quantifying the frequency doubling fluctuation quantity of active power and reactive power caused by a negative sequence component; a third harmonic voltage compensation method is adopted to suppress negative sequence current, the third harmonic voltage compensation amount of the converter is dynamically adjusted, and three-phase current balance is regulated and controlled; on the basis of active and reactive power fluctuation suppression of a negative-sequence current compensation method, an optimization function with the purpose of minimizing the comprehensive fluctuation quantity of active power and reactive power is constructed by utilizing controllable negative-sequence current compensation quantity and eliminating frequency doubling fluctuation quantity of active power and reactive power, and an optimal negative-sequence current compensation scheme is solved in real time by adopting a particle swarm optimization algorithm. Cooperative suppression of three-phase current balance and power oscillation is achieved, and the operation stability and the power transmission capacity of the inverter side converter under an asymmetric fault are remarkably improved under the current amplitude limiting condition.

The invention provides a virtual synchronous machine grid-connected control method and device and a readable storage medium, and relates to the technical field of electric power. The method comprises the following steps: calculating grid-connected active power and actual reactive power according to inverter parameters and power grid parameters of previous grid-connected control; determining the output voltage of the inverter according to the actual reactive power and the reference reactive power; inputting the grid-connected active power, the reference active power and the rated angular frequency into a first-order low-pass filtering module to obtain a frequency deviation and a frequency change rate, and adaptively adjusting the virtual inertia according to the power difference and the frequency deviation; updating the output angular frequency of the inverter according to the sum of the frequency deviation and the rated angular frequency; and performing voltage and current double-closed-loop control on the output voltage and the output angular frequency to obtain a modulated wave signal, and performing sine pulse width modulation based on the modulated wave signal to obtain a switching control signal of the inverter. Therefore, the active power oscillation is eliminated, the active steady-state deviation is reduced, and the frequency deviation and the frequency change rate are effectively inhibited.

The invention relates to an electric energy coordinated distribution system capable of quickly clearing faults of a power distribution network, which belongs to the technical field of power system protection and control, and comprises the following steps: generating a regional reference impedance matrix in advance based on power grid static topological data and load flow calculation; the system comprises an instantaneous feature analysis module, an evolution trend analysis module, a system stability evaluation module, a collaborative response evaluation module, a fault type judgment module and a response strategy generation module, the fault recognition time is shortened, improvement is carried out compared with a traditional method, the collaborative response precision of the distributed power supply is improved, and the system reliability is improved. The power oscillation risk is reduced, the transient stability margin of the system is improved, and the anti-disturbance capability is enhanced; the fault power failure time is reduced, the distributed energy utilization rate is improved, the new energy consumption space is increased, and the updating period of traditional protection equipment is delayed.

The invention provides a thermal power generating unit power oscillation on-line monitoring system, and relates to the technical field of monitoring, an output power sequence, a frequency sequence, an operation parameter set and a control instruction set are acquired through a data acquisition module, and a data processing module performs denoising, abnormal value elimination, time alignment and resampling on an original data set to generate a processed data set; the oscillation analysis module calculates an oscillation characteristic index based on the processing data set and generates an oscillation judgment result; the early warning module outputs an early warning signal when determining that power oscillation exists; the linkage control module generates a control instruction after receiving the early warning signal, and cuts off a frequency modulation action loop or adjusts frequency modulation related parameters; and the data storage module is used for carrying out structured storage on the processing data set, the oscillation characteristic indexes, the oscillation judgment result, the early warning signal and the control instruction. Therefore, real-time monitoring, accurate identification and rapid linkage control of power oscillation of the thermal power generating unit can be realized, and the operation stability of the unit and the safety of a power grid are improved.

The invention discloses a power feedback and phase compensation-based oscillation suppression strategy for a multi-configuration-network converter grid-connected system. The multi-configuration-network converter grid-connected system mainly comprises the following modules: a power calculation module, a virtual speed regulator module, a virtual rotor module, a reactive power-voltage droop control module and a voltage and current double-closed-loop module. In the virtual rotor module, the output active power and the output power angle are subjected to a differential link to construct a power feedback loop, the difference value between the output angular frequency of the virtual rotor and the rated power grid frequency is used as the phase compensation amount, and a power feedback and phase compensation strategy is applied; the problem that after grid connection, a multi-grid converter is prone to being disturbed by the power grid frequency to generate violent power oscillation is solved.

The invention discloses a turbine generator set power oscillation emergency valve switching control method, system, equipment and medium based on a thermodynamic model, and belongs to the technical field of electric power system automation control and thermal energy power engineering, and the method comprises the steps: monitoring the operation state of a set in real time, and collecting the current data of the set; calculating a theoretical balance valve position required for maintaining the current target power in real time by using the corrected inverse thermodynamic model; and the power fluctuation condition is monitored in real time, when it is detected that power oscillation happens to a unit and valve cutting logic is triggered, the system intercepts a conventional feedback instruction for tracking the actual valve position, the theoretical balance valve position is directly used as a target instruction, and a control valve is forcibly driven to act to the valve position through a rate limiter. According to the method, it can be ensured that after closed-loop control of the unit is cut off, the valve rapidly returns to the physical balance opening degree matched with the current load, an oscillation source is effectively eliminated, severe fluctuation of main steam pressure and temperature is stabilized, and the safety and stability of the unit under the abnormal working condition are remarkably improved.

The invention discloses a heterogeneous wind power plant power control method and system based on a hierarchical neural network. The method comprises the following steps: S1, acquiring heterogeneous wind turbine generator parameters; s2, establishing a heterogeneous wind power plant state space model according to the heterogeneous wind turbine generator parameters; s3, establishing a heterogeneous wind power plant prediction model based on a time domain convolutional network-self-attention mechanism hierarchical neural network, training the heterogeneous wind power plant prediction model through a training set constructed by heterogeneous wind turbine generator parameters, and outputting a model compensation amount to correct a heterogeneous wind power plant state space model; and S4, by taking minimization of voltage and power fluctuation of the heterogeneous wind power plant as a dual control target, on the basis of the corrected heterogeneous wind power plant state space model, through a time sequence optimization heterogeneous wind power plant power instruction, realizing dual suppression of voltage and power fluctuation. The method has the advantages of improving power prediction precision, suppressing voltage fluctuation and power oscillation and the like.

The invention relates to an anti-countercurrent device suitable for a miniature grid-connected inverter system, which is characterized in that an anti-countercurrent electric meter and at least one miniature grid-connected inverter form a local area network through a local router to form a system, and the anti-countercurrent electric meter accurately acquires power grid parameters through a power grid voltage sampling terminal and a current measurement signal input terminal of the anti-countercurrent electric meter; and the real-time grid-connected power of each micro grid-connected inverter is inquired regularly as a control center, a power adjustment instruction is calculated and broadcasted, and finally all the micro grid-connected inverters are driven to adjust output synchronously. An anti-countercurrent electric meter is used as a unified control core, and a unified power adjustment instruction is calculated based on real-time countercurrent power and total generated power, so that all micro inverters can adjust power synchronously and proportionally, accurate cooperative control of multiple micro inverters is realized, and power oscillation is avoided; the whole control closed loop operates in a high-speed local area network, is quick in response, meets the grid-connected standard requirement for eliminating countercurrent, and effectively guarantees the safe operation of a power grid.

The application discloses a power oscillation data processing method and device, a storage medium and an electronic device. The method comprises the following steps: determining a plurality of sites, and determining oscillation data corresponding to the plurality of sites respectively; inputting the oscillation data corresponding to the plurality of sites respectively into a target knowledge graph representation learning model to obtain a target knowledge graph representing the relationship between the plurality of sites; and determining an oscillation propagation path of a target oscillation anomaly included in the oscillation anomaly corresponding to the plurality of sites respectively based on the oscillation data corresponding to the plurality of sites respectively. The application solves the technical problem of lacking the ability of monitoring information analysis and display for wideband oscillation in the related art.

The application discloses a kind of based on real-time demand analysis's energy storage power station state evaluation method and system, it is related to power station state evaluation technical field, comprising: obtaining the real-time operation data of energy storage power station;Real-time operation data includes voltage data, current data, temperature data and power data;Based on real-time operation data, establish the real-time evaluation index system of energy storage power station under power grid system demand;Based on the real-time evaluation index system of energy storage power station, establish the performance comprehensive evaluation model of energy storage power station, and the state of energy storage power station is evaluated according to the performance comprehensive evaluation model of energy storage power station.The application obtains operation data from PCS converter, battery body and PCC point multidimension, combined with the systematic evaluation index system of four kinds of demands of power grid frequency modulation, peak regulation, voltage regulation and power oscillation suppression, using dynamic fuzzy comprehensive evaluation and adaptive weight dynamic adjustment combined evaluation method, the overall accurate evaluation of the state of energy storage power station is realized.

The present application belongs to the technical field of new energy network construction type converter, and particularly relates to an asymmetric damping voltage controller for a network construction type converter and a control method thereof, comprising the following steps: step 1: obtaining the inductance current of a filter and the capacitance voltage in the current system; step 2: a power calculation module calculates active power and reactive power; step 3: an active control loop and a reactive control loop obtain the active power and the reactive power; the phase angle generated by the active loop control and the reference value of the inverter output voltage amplitude are calculated; step 4: the asymmetric damping voltage controller obtains the phase angle, the reference value of the inverter output voltage amplitude and the capacitance voltage; and the asymmetric damping voltage controller is used to suppress power oscillation to generate an output current reference value; and a current controller is used to generate a modulation voltage signal. The present application provides an effective technical means for improving the stability and dynamic performance of power electronic equipment in a high penetration rate new energy scene.

The invention discloses a control method and device for suppressing active oscillation of an SG-VSG parallel system, electronic equipment and a storage medium. The method comprises the following steps: adjusting terminal voltage of an SG according to an SG power reference value and excitation voltage; inputting the reactive power of the VSG into a reactive power-voltage droop control module to obtain the voltage amplitude of the VSG; inputting the VSG power reference value and the active power of the VSG into a swing equation module, and outputting a phase angle of the VSG; the phase angle of the VSG and the voltage amplitude of the VSG are input into a voltage and current double-closed-loop module, and modulation reference voltage of the VSG is output; and inputting the modulation reference voltage of the VSG into a PWM modulation module to generate a switching signal, and controlling the opening and closing of an IGBT in the fan inverter to realize the adjustment of the voltage phase angle of the VSG. An output power high-frequency component is introduced into a VSG control structure, so that power fluctuation is reduced, the power angle response speed of the VSG and the power angle response speed of the SG tend to be consistent, and therefore power oscillation suppression is effectively achieved.

The invention discloses an instantaneous power distribution method and device of an isomorphic energy storage converter, terminal equipment and a storage medium, and belongs to the technical field of energy storage converter power distribution.The method comprises the steps that the energy storage output current, the energy storage output voltage, the energy storage input current and the output voltage instruction value of the isomorphic energy storage converter to be distributed are obtained; further calculating to obtain a first output current, a first correction current reference and a second correction current reference; performing gain amplification and difference suppression to obtain a third correction current reference; performing current outer loop control to obtain a phase shift angle of the isomorphic energy storage converter; and finally, performing on-off control on the isomorphic energy storage converter through the phase shift angle to obtain the instantaneous distribution power of the isomorphic energy storage converter. According to the invention, the problem that the continuous power oscillation of the isomorphic energy storage converter is caused because the same instantaneous power distribution cannot be carried out in the prior art can be solved.

The present application relates to photovoltaic and energy storage collaborative control technical field, especially to be applied to 5G integrated power supply photovoltaic control adjustment method and system, the present application proposes the following scheme, the photovoltaic characteristic parameter and corresponding time mark data are collected, three-dimensional curved surface model is constructed to carry out differential geometry curvature analysis, according to the curvature analysis result, the light change event type is determined and the photovoltaic maximum power point is positioned, according to the photovoltaic maximum power point, the photovoltaic output parameter adjustment and energy storage charging and discharging strategy is generated, the present application realizes the quick response to the quick fluctuation of light through the fusion of multidimensional characteristic parameters, adopts the positioning strategy of event-driven, improves the maximum power point tracking accuracy and dynamic stability, reduces power oscillation and energy loss, realizes the collaborative optimization of photovoltaic, energy storage and load.

The application discloses a power fluctuation smoothing control method and system for photovoltaic power station cluster, and particularly relates to the technical field of power system control, and is used for solving the power oscillation and instability problem caused by the existing smoothing control method due to neglecting the internal power grid dynamic characteristics of the cluster; by acquiring historical power flow and historical smoothing control instructions, the information transmission entropy distribution between the instructions and the flow under different frequencies is analyzed to identify the dominant oscillation mode frequency, the nonlinear interaction strength of the smoothing control loop of each substation is evaluated, and the time and space distribution inertia center of the node oscillation energy is calculated, the system dynamic instability criterion is constructed based on the nonlinear interaction strength and the inertia center offset trajectory, the dynamic safety constraint set with the target of inhibiting the oscillation mode is constructed when the criterion is established, and the smoothing control instruction optimization model is solved under the constraint set restriction to generate and execute new control instructions to each substation.

The present invention discloses an additional damping control method for improving the oscillation suppression capability of grid-type equipment, comprising: constructing a grid-type converter overall control structure of the converter using a virtual synchronous control method based on the generator rotor motion equation and the transient voltage equation; constructing an optimization strategy for additional power instruction limitation control, primary frequency regulation control, primary voltage regulation control and additional damping control of the overall control structure of the grid-type converter, wherein the additional damping control includes: a power oscillation damping controller and a virtual power system stabilizer; and completing the stability control voltage output of the power system through the grid-type converter overall control structure of the additional optimization strategy.

The application discloses a converter control method for improving power transmission stability of a flexible DC interconnection system, relates to the technical field of flexible interconnection system control strategies, and solves the power oscillation problem of the existing flexible DC interconnection device control method.The technical solution points are that the control modes of the converters on the two sides of the flexible interconnection system are adaptively switched according to the energy flow direction of the system.The technology realizes the control by coordinating the DC voltage, the power control outer ring, the limiter, the current control inner ring and other control links, superimposes the power control current feedback instruction after the limiter and the DC voltage control current feedback instruction as the current inner ring control instruction, and controls the operation of the power electronic converter through the current inner ring controller and the PWM modulation instruction.The inner ring current instruction value of the converters on the two sides of the flexible DC interconnection system is adaptively adjusted with the change of the system power flow direction, can be the control of the DC voltage or the control of the system power flow direction, and the control mode of the unilateral converter is not limited to the fixed DC voltage control or the fixed power control.Under the premise of ensuring the reliable and stable switching of the control modes of the two-side converters in the system, the system stability problem caused by the power flow direction under the fixed control mode of the unilateral converter is solved.

The invention discloses a virtual synchronous generator coordination control method and system, and belongs to the technical field of virtual synchronous generator control, and the method comprises the steps: constructing a multi-virtual synchronous generator parallel admittance model, and carrying out the dynamic compensation of a power angle in the multi-virtual synchronous generator parallel admittance model based on an equal area rule, and obtaining an active power reference value; inputting the active power reference value into the multi-virtual synchronous generator parallel admittance model, designing a phase angle decoupling coordination strategy to decouple a phase angle, and eliminating cross coupling in the multi-virtual synchronous generator parallel admittance model and interference of each phase angle control ring; and optimizing multiple virtual synchronous generator parallel admittance model parameters and verifying the system stability of the model to realize virtual synchronous generator coordination control. According to the method, the problems of phase angle coupling, power oscillation and synchronism of the multi-virtual synchronous generator parallel admittance model under asymmetric line parameters are solved, and the transient / steady-state performance and anti-disturbance capability of the model are improved.

The invention discloses a chained energy storage system and network construction hybrid control method based on state switching. The method comprises the following steps: 1) calculating related voltage, current, inductance and resistance; 2) calculating the number of power modules connected in series and parameters of a direct-current accumulator; 3) calculating a grid-following active current given value through a grid-following active regulator, and calculating a grid-following reactive current given value through a grid-following reactive regulator; 4) calculating given values of active current and reactive current of the network; (5) SCR is calculated through a state switching control unit, and state switching is carried out between network construction and network following; 6) obtaining a three-phase modulation wave through an active current and reactive current decoupling controller and an inter-phase voltage-sharing controller; 7, interphase voltage-sharing control is carried out through the interphase voltage-sharing controller, the switching pulse value of each power unit is obtained, corresponding switching tube driving pulses are generated, and state control is achieved.The method belongs to the technical field of chain type energy storage control, and the problems of overcurrent, voltage abrupt change and power oscillation during switching are avoided.

The invention relates to a battery charging and discharging control method for an energy storage system, and the method comprises the steps: collecting the voltage and temperature signals of a single battery in real time, dynamically constructing a safe operation range containing a current boundary and a temperature limit value, and generating a preliminary current distribution scheme based on the load demand of a power grid; and further predicting a risk monomer temperature rise track by using an electrothermal coupling model, dynamically correcting current distribution through negative feedback adjustment, and finally generating a charging and discharging instruction meeting a multi-constraint condition through distributed optimization. According to the method, the limitation of a traditional static threshold strategy is broken through, the power oscillation and thermal runaway risk caused by load sudden change or aging difference in a multi-battery-pack cooperation scene is solved, the system safety, the service life balance and the dynamic response capability are remarkably improved, and a high-robustness control normal form is provided for a large-scale energy storage power station.

The invention discloses a thermal power generating unit power oscillation logic judgment method, which comprises the following steps of: carrying out sliding sampling on a unit power signals, taking a unit power values before a (s), respectively carrying out low selection and high selection on the a power values, respectively carrying out difference calculation on the current unit power value, the low selection value and the high selection value, and comparing the difference value with a set change amplitude b (MW), so as to judge the power oscillation of a thermal power generating unit. Therefore, frequency accumulation judgment and stroke power oscillation alarm signals are respectively carried out. The method aims at judging unit power oscillation at the first time, triggering a power oscillation alarm and then cutting off power closed-loop regulation (a power loop of steam turbine master control automation and DEH local control in a CCS mode), so that a unit is in a stable state quickly.

The invention belongs to the technical field of stable control of a power system, and particularly discloses a power angle compensation-based method for quickly recovering active power after a fault of a network-forming converter, which comprises the following steps of: monitoring a voltage amplitude and a power difference value at a grid-connected point of the network-forming converter in real time; according to the voltage amplitude and the power difference value, identifying whether the network-forming converter is in an unstable state of active power oscillation after the fault is cleared; if the state is identified as an unstable state, calculating a power angle compensation amount used for counteracting power angle deviation caused by a fault based on detected voltage drop information and system impedance parameters; and superposing the power angle compensation value to a power angle generated by a power control ring of the network-forming type converter, and generating a compensated power angle instruction for controlling pulse modulation of the converter so as to realize active power recovery after the fault is cleared. The method can adapt to different power grid impedance conditions, quickly suppress power oscillation and realize quick recovery of active power, so as to improve the transient stability and reliability of a novel power system.

The invention discloses a Duffing-Hopf oscillator-based voltage feed-forward damping increasing method for a grid-forming inverter, and belongs to the technical field of power generation, power transformation or power distribution. In order to solve the problem that the stability and the reliability of a power system are damaged due to insufficient inertia and damping of a networking inverter based on a Hopf oscillator, the invention provides a Duffing-Hopf oscillator networking control method suitable for the networking inverter by combining the Hopf oscillator with a Duffing oscillator, extra inertia and damping response is provided for an inverter system, and the stability and the reliability of the power system are improved. Meanwhile, decoupling between inertia coefficients of the active power control loop and the reactive power control loop is ensured; in addition, a common coupling point voltage q-axis component feedforward damping lifting control method is provided to suppress active power oscillation caused by load fluctuation between multiple parallel inverter systems. The Duffing-Hopf oscillator networking control can provide enough inertia and damping to relieve the frequency change rate, and the common coupling point voltage q-axis component feedforward control can effectively suppress active power oscillation.

This application discloses a power control device, a chip, a charging case, and earphones, belonging to the field of power control. The device includes a DC-DC boost circuit, a low-power oscillation circuit, and a logic circuit. The logic circuit is connected to the other two circuits. The DC-DC boost circuit is connected to the output terminal and the power supply, and is used to output electrical energy from the power supply. The low-power oscillation circuit provides a periodic trigger signal to the logic circuit to determine whether the DC-DC boost circuit is activated when the earphones are continuously in the case. The logic circuit controls the DC-DC boost circuit to be activated during a first time period and deactivated during a second time period. The first time period is the period during which electrical energy is output to the output terminal via the power supply. By using the periodic trigger signal from the low-power oscillation circuit and the logic circuit to control the DC-DC boost circuit to be deactivated when it is determined that no electrical energy needs to be output to the output terminal via the power supply, the power consumption of the power control device can be reduced.

An oscillator is proposed that can produce much greater voltage than the input voltage. To accomplish this, the coil and the capacitor in the tank circuit are connected in series. This creates a high voltage point between the capacitor and the coil. However, in order to work it requires a special feedback method. Like the Hartley and Armstrong oscillators, it draws energy from the coil in the tank circuit, except it is accomplished by a separate coil placed a given distance away from the coil in the tank circuit. Ultimately this oscillator has advantages when high power is needed. It has a small component count and is easy to build. Currently if one wants to have high power oscillation, one uses a low voltage signal generator and then goes through several steps to amplify the signal. Here the oscillator already produces the high voltage. Another advantage in the design is that since the feedback has to provide the right amount of energy, this can be adjusted to the optimal feedback by manually adjusting the distance between the coils. Another advantage is that, when aligning the coils correctly, the oscillator produces a virtually perfect sine wave.