478 results about "Electric Capacitance" patented technology

The utility model discloses a silicon capacitor electrode structure and a silicon capacitor, which can further improve the capacitance of a capacitor in a limited space by nesting, combining and arranging a plurality of groups of element arrays distributed in a triangular grid mode more reasonably and precisely, so that the capacitor can store more charges.

The invention relates to the technical field of battery management, in particular to an intelligent charging adjustment method and system based on dynamic monitoring, and the method comprises the steps: determining a tested energy storage battery, determining a target battery based on a charging adjustment instruction, carrying out the feature extraction of a plurality of historical charging data and the previous full capacitance, and obtaining a charging emergency coefficient and a battery aging coefficient; a humidity sensor and a temperature sensor are used for obtaining current humidity and current temperature respectively, particle swarm simulation is carried out on a charging emergency coefficient, a battery aging coefficient, a constant current curve set, a constant voltage curve set, a switching curve set, the current humidity and the current temperature, and target constant current, target constant voltage and a target switching threshold value are obtained; and if the target battery voltage is greater than or equal to the target switching threshold, performing charging adjustment on the target battery according to the target constant voltage and the target switching threshold to obtain a final battery, and completing intelligent charging adjustment. The safety and stability of the charging process can be improved, and the service life of the battery is prolonged.

The utility model discloses a silicon capacitor electrode structure and a silicon capacitor, which can further improve the capacitance of a capacitor in a limited space by nesting, combining and arranging a plurality of groups of element arrays distributed in a quadrilateral grid mode more reasonably and precisely, so that the capacitor can store more charges.

The invention relates to a multi-region power system capacity configuration determination method considering intra-region and inter-region market joint clearing of a capacity market, and the method comprises the steps: constructing a clearing model for intra-region and inter-region electric energy market joint optimization and a capacity market clearing model, and determining the coupling constraint of the intra-region electric energy market and inter-region power purchase, and establishing a joint clearing model to obtain a double-layer optimization model, and solving the joint clearing model by using a Karush-Kuhn-Tucker condition to obtain a joint optimization scheme of power generation installed capacity configuration of each region, cross-region power transmission capacity distribution and system reserve capacity configuration. According to the method, the capacity market, the intra-regional electric energy market and the inter-regional electric energy market are comprehensively considered, so that combined clearing of the electric energy market and the capacity market is realized on the premise of ensuring the stability of the power system, and optimal configuration of resources and coordinated clearing of the electric energy market and the capacity market are realized in the regional market range; and technical support is provided for combined stable operation of a future capacity market and an electric energy market.

The invention discloses a preparation method of high-rate fast-charging graphite from a semi-calcined coke raw material, and belongs to the technical field of batteries, and the preparation method comprises the following steps: S1, crushing and shaping the semi-calcined coke raw material; s2, carrying out graphitization high-temperature treatment on the crushed and shaped semi-calcined coke; s3, mixing and coating the semi-calcined coke subjected to graphitization high-temperature treatment with a coating agent; s4, performing high-temperature carbonization heat treatment on the semi-calcined coke mixed and coated with the coating agent; s5, screening the petroleum coke semi-calcined coke subjected to high-temperature carbonization heat treatment to obtain a semi-calcined coke raw material high-rate fast-charging graphite; the material has the advantages of large discharge capacity, good cycle performance, good electrochemical performance, high discharge plateau and plateau retention rate, good large-current charge-discharge performance, good safety, good adaptability to electrolyte and other additives, stable product properties, almost no difference between batches, simple and feasible preparation method, and suitableness for industrial production.

The invention relates to the field of power system equipment detection, in particular to a residual magnetism measuring device and method for a large power transformer. The residual magnetism measuring device for the large-scale power transformer comprises the large-scale power transformer, a high-voltage bushing, a high-voltage neutral point bushing, a low-voltage bushing, an iron core outgoing line bushing, a first capacitor, a second capacitor, a detection impedor, a partial discharge instrument and a large-current generator, the capacitance of the first capacitor is 30pf-40pf and is matched with the capacitance of a transformer iron core, and the capacitance of the second capacitor is 300pf-400pf and is 10 times proportional to the capacitance of the first capacitor; the method comprises the following steps: carrying out a long-time induction withstand voltage and partial discharge test after a conventional test, measuring discharge amounts Q1, Q2 and Q3 at 0.5, 1 and 1.5 times of rated voltages, judging residual magnetism according to the difference value of the discharge amounts and an iron core grounding current, and if the residual magnetism exceeds the standard, magnetizing and demagnetizing by using a large current generator at the frequency of 150Hz. The method has the advantages that the residual magnetism is measured and evaluated in time, equipment faults are avoided, operation is easy and convenient, and adaptability is high.

The invention discloses a lithium ion battery capacitance detection method, which comprises the following steps: constructing a first training model containing association of charging and discharging data and ultrasonic characteristics based on a calibrated battery, and accurately utilizing ultrasonic feedback information to analyze internal characteristics of the battery; when a tested battery is analyzed, a spatial distribution and energy propagation characteristic correlation model is obtained by means of the model, and the change conditions of an internal structure and a propagation path can be rapidly judged, such as abnormities of electrode material falling, diaphragm damage and the like; and meanwhile, the internal first capacity is flexibly determined by integrating the ultrasonic characteristic contribution and the second capacitance data, so that the actual charge-discharge performance of the battery is considered, the potential of the ultrasonic characteristics for capacity evaluation is deeply excavated, and the accuracy and reliability of the internal state evaluation of the battery are effectively improved.

The present application relates to the technical field of information, and provides a lid open / close detection method. The method comprises: in each detection cycle, sending a driving signal to a first touch electrode of a touchpad or a second touch electrode of a touch screen, and detecting a mutual capacitance generated between the first touch electrode and the second touch electrode; on the basis of the mutual capacitance and a first mapping relationship, determining a folding angle range of an electronic device, the first mapping relationship representing correspondences between capacitances and folding angle ranges; and on the basis of the folding angle range of the electronic device, determining a lid open / close state of the electronic device. By using the method to detect the mutual capacitance between the touchpad and the touch screen of the electronic device, lid open / close detection for the electronic device can be implemented, effectively improving the efficiency of lid open / close detection while reducing costs.

The invention relates to the technical field of sensors, and discloses a capacitive touch detection circuit and method.The capacitive touch detection circuit comprises a charge compensation module, a voltage and current conversion module, an integrating capacitor, a quantization circuit module and a counter; the charge compensation module is used for performing charge and discharge compensation on the external touch capacitor and adjusting the charge quantity on the touch capacitor to be within a preset charge quantity range corresponding to the reference voltage; the voltage and current conversion module is used for converting residual charges on the touch capacitor compensated by the charge compensation module into current and outputting the current; the integrating capacitor is used for integrating the current to obtain an integrated voltage; the quantization circuit module is used for quantizing the integral voltage and controlling the integral voltage to be stabilized in a preset voltage range of the reference voltage; and the counter is used for counting the output of the quantization circuit module to obtain a digital code representing a touch capacitance value. According to the invention, the touch detection performance with high linearity, low power consumption, small area and high noise resistance can be realized.

The invention relates to the technical field of electrical equipment insulation tests, and discloses a medium-voltage cable variable-frequency resonance voltage-withstanding test system and a medium-voltage cable variable-frequency resonance voltage-withstanding test method. The method comprises the steps of configuring a test loop and setting related parameters, and presetting a target test voltage, test time, a system quality factor range, a local discharge capacity threshold and a current change rate threshold based on a cable model, a cable length, a laying environment temperature and an equivalent capacitance. And executing frequency scanning in a preset frequency range through an adaptive step length strategy, adjusting the step length according to the current response, identifying the resonant frequency and verifying the quality factor of the system. In the test process, the loop current change rate, the partial discharge capacity and the equipment temperature are monitored in real time, a protection mechanism is triggered according to abnormal characteristics, and insulation state diagnosis is completed. When the test is ended, voltage is reduced at a controllable rate, residual charges are dissipated, and a test report is automatically generated. The method improves the accuracy and safety of the test, and is suitable for various field conditions.

The embodiment of the invention relates to the technical field of battery management, in particular to a battery discharge capacity prediction method, a model training method, equipment and a medium. The method mainly comprises the following steps: acquiring first feature data corresponding to a preset initial feature from a preset battery data set, inputting the first feature data into a random forest model for training, screening decision trees of the random forest model to obtain a target decision tree meeting a preset first screening standard, and determining whether the target decision tree meets the preset first screening standard or not; and screening the initial features in the target decision tree to obtain second feature data corresponding to key features, inputting the second feature data into an initial LSTM model for training, and performing hyper-parameter optimization on the initial LSTM model by using a whale optimization algorithm to obtain the discharge capacity prediction model. By adopting the method, the training speed of the model can be increased, and the prediction precision of the model can be improved.

The invention relates to the field of sodium ion batteries, and particularly discloses a multi-element doped P2 type layered oxide and a preparation method thereof. The chemical general formula of the multi-element doped P2 type layered oxide is NaxMyAzB1-y-zO2-tCt, x is greater than or equal to 0.6 and less than or equal to 0.85, M comprises one or more of Mn, Ni, Fe, Cu and Co, and y is greater than or equal to 0.5 and less than 1; a comprises one or more of Zn, Mg and Al, and z is more than 0 and less than 0.5; b comprises one or more of B, Mo and W; c comprises one or more of F, Cl and N, and t is more than 0 and less than 0.1. According to the multi-element doped P2 type layered oxide and the preparation method thereof, the problems that an existing P2 type layered oxide is limited in discharge capacity and poor in stability are solved.

The application discloses a method for screening lithium ion battery self-discharge, comprising the following steps: obtaining N qualified battery cells after formation aging; heating and aging the obtained N battery cells; placing the battery cells after heating treatment for a first standing time, and then performing constant current discharge for a first preset time, wherein the constant current discharge capacity is recorded as a first capacity; performing constant current discharge after the N battery cells are fully charged by constant current and constant voltage, wherein the constant current discharge capacity is recorded as a second capacity; calculating the average value of the capacity attenuation rate of the N battery cells during heating and aging based on the first capacity and the second capacity; beneficial effects: the first capacity ratio screening mainly eliminates battery cells with abnormal chemical self-discharge, the second static voltage drop screening mainly eliminates battery cells with large physical self-discharge, and the third voltage drop screening after dynamic charge and discharge cycles can effectively capture battery cells with weak physical self-discharge that escape in the first voltage drop screening.

The invention discloses a safe power distribution device and system, and the device comprises a power distribution cabinet, the side wall of the inner cavity of the power distribution cabinet is provided with a pedestal, the side wall of the pedestal is provided with a plurality of circuit breaker assemblies, each circuit breaker assembly comprises a circuit breaker body, the side wall of each circuit breaker body is provided with an operation handle, and the bottom of the inner cavity of the power distribution cabinet is provided with a zero line bar assembly. According to the safe power distribution device and the safe power distribution system, the plug seat is inserted into the connector circuit breaker for overall plugging, so that the replacement is safer and faster, and the maintenance is more convenient; through the design of combining a plurality of pins with the connector assembly, synchronous, rapid and one-time establishment and separation of all electrical connections can be realized, the risk of electric shock caused by frequent operation can be avoided, secondly, the connection male seat and the connection female seat are spliced to splice the bus bar to realize on-demand expansion of the power distribution capacity and the number of loops, wire arrangement inspection is facilitated, and the working efficiency is improved. The zero line bare wire head is pressed through resilience force of the conductive reed, so that wiring is more convenient and stable.

The invention provides a CeO2 / RGO / LTO ternary composite material capable of being used as a negative electrode of a lithium ion battery and a preparation method and application of the CeO2 / RGO / LTO ternary composite material in the technical field of lithium battery electrode materials, and the CeO2 / RGO / LTO ternary composite material is formed by ternary compounding of cerium dioxide, reduced graphene oxide and lithium titanate. By means of step design, morphology control and interface construction, it is ensured that all components are evenly distributed, a strong synergistic effect is generated, the electrochemical performance of lithium titanate is remarkably improved, the problems that lithium titanate is low in conductivity and rapid in capacitance fading are solved, solidified lithium ions are converted into oxide with a stable structure, and the technical effect of restraining gas production is achieved. And the lithium ion battery is expected to be used for high-power and long-life lithium ion batteries, and particularly shows huge potential in the field with extremely high requirements on safety and fast charging performance.

The utility model discloses a direct current power supply circuit and a lamp, and relates to the technical field of circuits and lamps, the direct current power supply circuit comprises a combined type electrolytic capacitor which is connected in parallel in a direct current circuit obtained by rectification of a rectification circuit, the combined type electrolytic capacitor is formed by connecting two electrolytic capacitors in series, one electrolytic capacitor is a large-capacitance low-voltage electrolytic capacitor, the other electrolytic capacitor is a small-capacitance high-voltage electrolytic capacitor, and the negative electrode of the large-capacitance low-voltage electrolytic capacitor is connected with the positive electrode of the small-capacitance high-voltage electrolytic capacitor. The two electrolytic capacitors are small in size, small in size after being combined, and small in occupied space.

The present disclosure relates to a capacitance multiplier for decoupling capacitors. An integrated circuit can include one or more circuits coupled to a capacitance multiplier circuit. The capacitance multiplier circuit can include a capacitor, fixed and tunable resistors, and a transconductance circuit. The tunable resistor can be adjusted to control the total capacitance of the capacitance multiplier circuit. The transconductance circuit can include a transistor having a drain terminal coupled to a first electrical component and a source terminal coupled to a second electrical component. The first electrical component can be a diode-connected transistor, a direct shorted wire, a resistor, an inductor, or a current source. The second electrical component can be a current source, a direct shorted wire, a resistor, an inductor, or another diode-connected device. Configured in this way, the capacitance multiplier circuit can provide a large adjustable capacitance without voltage drop and without consuming a large amount of power.

The application discloses a kind of data center intelligent power distribution system electric capacity dynamic monitoring and early warning method, it is related to electric capacity dynamic monitoring technical field, including using current decomposition method to the power load of data center power supply system is hierarchized decomposition, obtain current, pre-increased current and charging current;Using dynamic aggregation calculation method to the current data after decomposition is gradually summarized, obtain the expected current, maximum current and expected maximum current of each level;Using load rate calculation method to the current data after aggregation is normalized, obtain the current load rate, expected current load rate, maximum current load rate and expected maximum current load rate of each level;Using three-level early warning threshold method to the load rate obtained by calculation is threshold comparison, and according to preset light load, heavy load, overload threshold triggers corresponding level capacity early warning signal;Using scene adaptation method to early warning signal is classified processing.

The utility model provides an integrated busbar structure, a battery pack and a vehicle, and relates to the technical field of battery packs. The integrated busbar structure comprises a copper aluminum bar which is electrically connected with a battery cell in a battery cell module; the acquisition assembly is used for acquiring parameters of the battery cell module; the insulating part is used for being arranged on the battery cell module, the first side of the insulating part is used for being arranged towards the battery cell module and is provided with at least two mounting positions, and the copper-aluminum bar and the acquisition assembly are arranged on the corresponding mounting positions; the insulation characteristic of the insulation part can play an insulation protection role on the copper-aluminum bar and the acquisition assembly, and a protection part for insulation protection on the copper-aluminum bar and the acquisition assembly does not need to be additionally arranged, so that the utilization rate of the insulation part is improved, the occupied space is reduced, more battery cell modules are arranged, and the capacitance of the battery pack is improved; and a protection piece is not required to be additionally arranged, so that the cost is reduced.

The invention discloses a low-speed charging pile and distributed photovoltaic cooperative power supply method, which is applied to a power supply system comprising a distributed photovoltaic power generation system, a plurality of low-speed charging piles and a cooperative controller. The method comprises the following steps: collecting photovoltaic real-time power, a charging pile state, a user charging demand, a power grid net load and environment prediction data; the guarantee power of each charging pile and the total guarantee power demand of the system are calculated, and the dynamic available charging capacity is determined; formulating a day-ahead reference charging power plan curve based on photovoltaic power prediction and charging demand prediction; in a real-time control period, actual photovoltaic power is compared with a planned value, power which can be increased or needs to be reduced is dynamically identified, and real-time optimal distribution is carried out by taking the condition that all guaranteed power is preferentially met as a constraint. According to the method, the photovoltaic local consumption rate is effectively improved, the power impact on the power distribution network is stabilized, and the core charging demand of a user is guaranteed on the premise of not depending on large-scale energy storage.

The utility model relates to the technical field of energy storage batteries, in particular to a battery box and an energy storage device, and the battery box comprises a first shell, a transition supporting piece, a second shell and a sealing component; the transition supporting piece is arranged between the first shell and the second shell and connected with the first shell and the second shell to form a shell. The transition support forms a first mating portion located inside the housing, the second housing forms a second mating portion located inside the housing, and the sealing member is compressed between the first mating portion and the second mating portion. Visibly, the transition supporting piece is installed at the butt joint position of the second shell and the first shell, the first matching part and the second matching part are introduced into the shell, and the sealing component is installed between the two matching parts, so that all structures are hidden in the shell and cannot protrude out of the shell; therefore, the residual space in the shell can be fully utilized, the space utilization rate can be improved, the capacitance of the battery box is improved, and the appearance is more attractive.

The application relates to the technical field of metrological calibration, and discloses a multi-voltage-grade capacitor current tester calibration method based on unified transformation ratio. The method comprises the following steps: screening unified transformation ratio parameters meeting range constraints and error constraints, obtaining a ratio difference parameter of a corresponding electromagnetic voltage transformer, obtaining a capacitance ratio difference correction factor, calculating conversion coefficients under each voltage grade, determining a primary side capacitance setting value according to a preset primary side calibration capacitance value and the conversion coefficients, obtaining a secondary side output capacitance value of a standard capacitance tank, and collecting a displayed capacitance value and a displayed capacitance current value. The conversion coefficients between the unified transformation ratio and the theoretical transformation ratios of each voltage grade are established, single transformation ratio is used to cover multi-voltage-grade calibration, error components introduced by the ratio difference of the electromagnetic voltage transformer in the capacitance calibration process are reduced, and different transformation ratio equipment needs to be frequently replaced.

The invention provides an operation maintenance method suitable for a lithium metal secondary battery. The operation maintenance method comprises the following steps: performing charge-discharge maintenance on the lithium metal secondary battery; and the charging and discharging maintenance comprises the following steps: after the lithium metal secondary battery is circularly used every 60 times, carrying out 0.1 C constant-current charging to 4.35 V, standing for 10 minutes, carrying out 1.0 C constant-current discharging with the discharging capacity of 2.5 Ah, and standing for 10 minutes again. The method has the beneficial effects that through targeted charging and discharging maintenance, uncontrollable growth of lithium dendrites in the service process of the lithium metal secondary battery is effectively inhibited, rapid generation of an irreversible SEI film and accumulation of dead lithium are slowed down, and use safety of the battery in the whole life cycle is guaranteed; maintenance operation is periodically executed in the normal use period of the lithium metal battery, the electrode interface state can be actively optimized, invalid consumption of active lithium is reduced, rapid increase of internal resistance of the battery and irreversible expansion of thickness are avoided, the cycle life of the battery is further prolonged, and the capacity retention ratio under the same use period is improved.

The application discloses a power supply system and method for storage products, and relates to the technical field of power supply, which comprises a main power supply module, a backup power supply module and a power supply bus. The main power supply module is responsible for target power supply under normal conditions, and the backup power supply module sets an output capacity according to an optimized single cache backup energy consumption of the storage product. When the main power supply fails, the backup power supply outputs backup power through the power supply bus. The problem that the system space is too large and the power density is limited due to extensive design of the backup power supply capacity in the prior art is solved, and the beneficial effects of optimizing the power supply system architecture and significantly improving the system space utilization and power supply reliability are achieved.

The utility model belongs to the technical field of switching power supplies, and particularly relates to a capacitance monitoring and adjusting circuit of a switching power supply. The power conversion circuit is connected with the input circuit; the control circuit comprises a controller, a switch tube and a first resistor, a first end of the controller is connected with the electrolytic capacitor, a grid electrode of the switch tube is connected with a second end of the controller, a drain electrode of the switch tube is connected with the power conversion circuit, a first end of the first resistor is connected with a third end of the controller, a source electrode of the switch tube is connected, and a second end of the first resistor is grounded; according to the capacitor monitoring and adjusting circuit, the capacitance of the electrolytic capacitor is compared with the set threshold value through the controller, and when the capacitance of the electrolytic capacitor is smaller than the set threshold value, the controller adjusts the duty ratio of the switching tube and reduces the output power of the switching power supply, so that the working ripple current of the electrolytic capacitor is reduced; the capacitance of the electrolytic capacitor is monitored in real time on the premise that the circuit complexity is not increased, so that the use safety of the switching power supply is improved.

The application provides a preparation method of a silicon-carbon composite negative electrode material, comprising the following steps: nanocrystallizing silicon material under a protective environment to obtain nanosilicon; self-assembling the nanosilicon with a first carbon source and a high polymer, and then adding a second carbon source to perform self-assembly, to obtain layered nanosilicon; granulating the layered nanosilicon to obtain a precursor; and sintering the precursor at a sintering temperature of 800 DEG C to 1200 DEG C to obtain the silicon-carbon composite negative electrode material. The application also provides a silicon-carbon composite negative electrode material and a battery comprising the same. The preparation method is simple in process, easy to control the process, and suitable for industrial production, and the prepared silicon-carbon composite negative electrode material can inhibit expansion and has improved conductivity and capacity.

The utility model relates to a metalized film capacitor in the technical field of capacitors, which comprises an electrode core, the electrode core is composed of a first metal foil, a first insulating layer, a metalized film, a second metal foil and a second insulating layer, one end of the first insulating layer extends outwards to form a reserved glue joint section, the reserved glue joint section is folded towards the bottom end face of the second insulating layer, and the metalized film is arranged on the metalized film. The first insulating layer is connected with the second insulating layer through the reserved glue joint section, and the first metal foil, the first insulating layer, the metallized film, the second metal foil and the second insulating layer are wound through one end close to the reserved glue joint section to form a columnar structure, so that the capacitor is broken down through the metallized film and is self-healed under the condition of overvoltage, and the service life of the capacitor is prolonged. And meanwhile, the minimum working capacitance of the capacitor can be ensured through the metal foil with good ductility, so that the metallized film capacitor can still keep effective working capacitance through the metal foil after multiple times of self-healing.

The embodiments of the present application relate to the technical field of power electronics, and disclose a power conversion apparatus, an uninterruptible power supply, and a photovoltaic inverter, which address the problem where large errors in sensing an alternating current capacitor current prevent accurate online measurement of a capacitance of the alternating current capacitor, resulting in the inability to accurately determine whether the alternating current capacitor is faulty. The specific solution provides a power conversion apparatus. The power conversion apparatus comprises an inverter circuit, an inductor, a capacitor, and a current sampling circuit. A positive input terminal of the inverter circuit is connected to a positive direct-current bus, a negative input terminal of the inverter circuit is connected to a negative direct-current bus, the inductor is arranged between an output terminal of the inverter circuit and an output terminal of the power conversion apparatus, and the capacitor and the current sampling circuit are arranged in series between the output terminal and a grounding terminal of the power conversion apparatus. The current sampling circuit is configured for sampling a current value of the capacitor.

The invention discloses a low-temperature-resistant negative electrode zinc paste and a low-temperature alkaline zinc-manganese battery containing the zinc paste. The negative electrode zinc paste comprises the following components in parts by weight: 60-65 parts of zinc powder, 1-2 parts of a composite conductive agent, 0.1-0.3 part of a composite corrosion inhibitor and 35-38 parts of a low-temperature electrolyte; the low-temperature electrolyte comprises a multi-element nonionic surfactant system, a multi-element nano anti-freezing agent system and a mixed solution A, the 3.9 ohm discharge capacity of the battery under the condition of-40 DEG C is larger than or equal to 60% compared with the capacity retention rate at normal temperature, the interface impedance amplification is smaller than or equal to 15%, the hydrogen evolution amount is reduced by 80% on year-on-year basis, the process is compatible with an existing production line, and the battery is suitable for polar scientific investigation and electronic equipment in plateau and cold regions.

The invention relates to a control method for a resonant converter. The control method comprises the following steps: determining a first turn-off threshold range and a first switching frequency of the resonant converter in a current first working mode; detecting an input voltage and an output voltage of the resonant converter to determine a current voltage gain of the resonant converter; determining a second switching frequency of the resonant converter in a second working mode to be switched to based on the current voltage gain and load of the resonant converter; calculating a second turn-off threshold range in a second working mode based on the first turn-off threshold range, the first switching frequency, the capacitance of the resonant capacitor and the second switching frequency; voltage feedback at the two ends of the resonant capacitor is collected in real time, and when the voltage feedback exceeds a first turn-off threshold value range, the turn-off threshold value of the resonant converter is switched to a second turn-off threshold value range, and the resonant converter is switched from the first working mode to the second working mode by enabling corresponding switches in the two-phase bridge arms in the full-bridge conversion circuit.