43 results about "Cascade circuits" patented technology

The invention provides a PWM / Buck cascade circuit auxiliary electrolytic hydrogen production rectification power supply and a control method, and relates to the technical field of electrolytic hydrogen production power supply and intelligent power grids, and the power supply comprises a main power loop and an auxiliary power loop; the main power loop comprises a multi-pulse thyristor rectifier, the power supply side of the multi-pulse thyristor rectifier is connected with an alternating-current power grid, the load side of the multi-pulse thyristor rectifier is connected with one end of a direct-current smoothing reactor, and the other end of the direct-current smoothing reactor is connected with the electrolytic bath; the auxiliary power loop comprises a PWM rectifier and a Buck circuit which are connected in series, the output end of the Buck circuit is connected to the output end of the main power loop in parallel through a direct-current LC filter, the output end of the Buck circuit and the output end of the main power loop are jointly connected into an electrolytic bath for ripple compensation, the multi-pulse rectifier adopts PI control, the PWM rectifier adopts voltage and current double-closed-loop control and SVPWM modulation, Buck adopts PI and feedforward compound control, and the output end of the Buck circuit and the output end of the main power loop are connected in parallel. The system has the advantages of improving the grid-side electric energy quality, the voltage utilization rate, the water electrolysis hydrogen production efficiency and the operation stability.

The invention relates to the field of clean energy electrolysis hydrogen production, in particular to a three-section electrolytic bath hydrogen production power supply system and a power supply control method thereof. According to the system, an alternating current bus module is connected with three-phase alternating current and provides a three-phase alternating current power supply; the power supply conversion module comprises three power supply conversion units, the three power supply conversion units are jointly connected to the alternating current bus module in parallel, and each power supply conversion unit converts the three-phase alternating current power supply into a working direct current power supply; the three-section type electrolytic bath comprises three sub-electrolytic baths which are connected in series, and each sub-electrolytic bath is correspondingly connected with one power supply conversion unit to obtain the working direct-current power supply; the power supply conversion unit comprises a rectification circuit, a three-level BUCK circuit and a resonance LLC cascade circuit which are connected in sequence. According to the invention, accurate power distribution and independent decoupling control of a load section are realized through the independent modular power supply; meanwhile, harmonic interference is restrained, the power factor is improved, and device stress and line loss are reduced.

The embodiment of the invention discloses a fast charging chip cascade circuit and a control method thereof, and relates to the technical field of switching power supplies, the fast charging chip cascade circuit comprises an AC / DC conversion loop and at least two fast charging chips; the fast charging chip comprises a logic control module, a cascade communication module and a constant voltage loop. The cascade communication module is provided with a cascade pin, a signal receiving pin and a signal sending pin, and the cascade pins of all the quick charge chips are electrically connected; the input end of the logic control module is electrically connected with a signal receiving pin and a signal sending pin in a corresponding fast charging chip, the output end of the logic control module is electrically connected with the constant voltage loop, and the constant voltage loop is electrically connected with the alternating current and direct current conversion loop. The voltage regulation conflict in the cascade state is effectively avoided, and the voltage regulation accuracy of the output voltage is improved.

According to the double-line cascaded LED driving circuit and the communication method thereof provided by the invention, two lines, namely the clock line and the data line, are adopted, and data communication and connection between LED drivers are realized through a communication mode of two-line input and two-line output; meanwhile, the forwarding identification in the input data is obtained through the arranged data cascade circuit in the LED driver, and the clock signal and the data corresponding to the forwarding identification are used as the input driving data of the LED driver of the next level based on the forwarding identification, so that the LED driver of the whole driving unit only needs to drive one LED driver, and the driving efficiency is improved. Therefore, high-speed data transmission can be realized, and meanwhile, the wiring mode between the controller and the LED drivers and the wiring mode between the LED drivers are simplified, and the hardware wiring difficulty is lowered.

The invention discloses an aluminum alloy melt rapid and uniform cooling device and method.The aluminum alloy melt rapid and uniform cooling device comprises a box body, an upper cooling unit, a lower refrigeration cycle unit and a control unit, the upper cooling unit is provided with a plurality of independent controllable coolers, and each independent controllable cooler comprises a heat insulation protection sleeve, a spiral heat exchange pipe, a heat conduction sleeve and a crucible from outside to inside; a thermocouple arranged in a quartz tube at the bottom of the crucible extends to the geometric center of the melt for real-time temperature measurement, the lower part adopts a high-temperature and low-temperature cascade loop for cooling, a safety branch is connected in parallel to maintain low-load operation of the compressor, and a control unit dynamically regulates and controls an electromagnetic valve, the compressor and an expansion valve through a PLC based on temperature measurement data. According to the cooling method, precise temperature control is achieved through system self-inspection, graded starting, temperature threshold value switching and safe shutdown, the multiple melts can be synchronously, rapidly and evenly cooled, the internal temperature difference is reduced, component segregation and structure non-uniformity are restrained, sampling consistency is guaranteed, and reliable support is provided for aluminum alloy melt quality evaluation.

The invention provides a power synthesis circuit, a radio frequency circuit, a radio frequency power supply and semiconductor process equipment, and is applied to the technical field of semiconductor equipment, the circuit comprises a plurality of synthesis transformers, the primary side of each synthesis transformer is used for being connected with a power amplification module, and the secondary side of each synthesis transformer is sequentially cascaded to form a cascade circuit; and outputting a synthetic power by the obtained cascade circuit. As the secondary sides of the synthesis transformers are cascaded in sequence, the power synthesis circuit synthesizes and outputs the power provided by the power amplification modules in a voltage superposition form, any two adjacent power amplification modules are isolated through the two synthesis transformers, a balance resistor is cancelled, and when any one power amplification module is abnormal, the power amplification module is switched off. When the abnormal module is detected, only the power reduction value corresponding to the abnormal module is reduced, the output of other power amplification modules in the power synthesis circuit is not influenced, greater power loss is avoided, and the reliability and the stability of the power synthesis circuit in the working process are effectively improved.

The utility model relates to the technical field of photovoltaic power generation, and discloses an inverter topological structure, which comprises an MPPT cascade circuit, a DC voltage conversion circuit and an inverter circuit, and is characterized in that the MPPT cascade circuit can independently track the maximum power of each photovoltaic module string and adjust the output current and the output voltage of each photovoltaic module string; the output of other photovoltaic module strings is adapted, and the wooden barrel effect of the photovoltaic module string of the inverter is solved; the combination of the MPPT cascade circuit and the direct-current voltage conversion circuit realizes the assembly-level maximum power tracking adaptive to the whole range in the single inverter, and can meet the work of a single assembly to provide a voltage source meeting conditions for a post-stage circuit; and the inverter circuit can meet the functional requirements of reactive power dispatching of the power grid.

The embodiment of the invention provides a circuit suitable for on-line monitoring of the on-state voltage drop of a crimping type IGBT, and a silicon carbide cascade circuit comprises at least two silicon carbide JFETs. The first end of the low-voltage clamping circuit is electrically connected with one end of the sampling circuit; the second end of the low-voltage clamping circuit is electrically connected with the other end of the sampling circuit; the third end of the low-voltage clamping circuit is electrically connected with one end of the silicon carbide cascade circuit; the other end of the silicon carbide cascade circuit is used for being connected with one end of a monitored IGBT; and the second end of the low-voltage clamping circuit is also used for being connected with the other end of the monitored IGBT. According to the scheme, the silicon carbide JFETs are cascaded to withstand high voltage of 4.5 kV and above, the voltage on each JFET is distributed in a balanced mode, the output voltage is clamped to be below 5V, meanwhile, the on-state voltage drop of the IGBT can be accurately transmitted to a sampling circuit, meanwhile, the transmission error of the on-state voltage is low, the proposed clamping circuit does not need an additional power supply and a compensation circuit, and the clamping circuit is simple in structure and low in cost. The method has the advantages of high precision, fast response and low cost.

The invention provides an acquisition circuit and acquisition equipment. The acquisition circuit comprises a power supply end, a load connection end, a multi-channel sampling circuit and a control circuit. The multi-path sampling circuit is electrically connected with the power supply end and the load connection end respectively; and each sampling circuit at least comprises two sampling branches which are connected in parallel. The control circuit comprises a controller and a cascade circuit electrically connected with the controller, the cascade circuit comprises multiple paths of enabling ports, the enabling ports are correspondingly and electrically connected with the sampling branches, and the controller controls the multiple paths of sampling circuits to perform independent sampling or synchronous sampling through the multiple paths of enabling ports; wherein one corresponding sampling branch is controlled to perform sampling through one enabling port. According to the sampling circuit, independent sampling or synchronous sampling of the multiple sampling circuits can be achieved, so that the multi-channel testing requirement is met, each sampling circuit can control the corresponding sampling branch to conduct sampling according to the actual situation, accurate testing is achieved, the testing requirement is met, and the user experience is improved.

The application discloses a series connection unit cascade circuit and a high-voltage cascade device, and relates to the field of circuit design.The series connection unit cascade circuit comprises a first series connection unit, a second series connection unit, a voltage dividing circuit, a floating ground and a floating resistor.The first series connection unit and the second series connection unit are connected in series to meet the high-voltage requirement of the high-voltage cascade device, and the power supply ends of the first series connection unit and the second series connection unit are connected with the floating ground through the voltage dividing circuit.The floating ground is connected with the ground through the floating resistor, so that the highest voltage between the devices in the first series connection unit and the second series connection unit and the floating ground at any time will not be greater than the voltage of the power supply for supplying power to the series connection unit, thereby solving the working voltage endurance problem of the devices in the series connection unit, and enabling the high-voltage cascade device to integrate more series connection units.

This disclosure is directed to digital front-end circuitry of a memory device having widened operating frequency bandwidth. The digital front-end circuitry may include a receiver including a variable gain amplifier (VGA) and a continuous time linear equalizer (CTLE) integrated on three cascaded circuit stages. A first stage of the three cascaded circuit stages may include a first portion of the VGA and a first portion of the CTLE, a second stage may include a remaining portion of the VGA, and a third stage may include a remaining portion of the CTLE. Having three cascaded circuit stages (e.g., including the remaining portion of the CTLE) as opposed to two cascaded stages may widen the operating frequency bandwidth of the receiver. The third stage may be programmable to be activated or deactivated.

The invention relates to the technical field of electronic testing, in particular to a scattering parameter determination and de-embedding method and device of a welding type test fixture and a medium. The method comprises the following steps: obtaining the insertion loss of a test fixture; acquiring an impedance change curve of a first cascade circuit where the test fixture is located; wherein the first cascade circuit is a cascade circuit formed by welding the test fixture on a test welding point of a tested object; fitting the impedance change curve through an artificial circuit of the first cascade circuit to obtain impedance and time delay of the test fixture in a first welding state of forming the first cascade circuit; and determining a scattering parameter value of the test fixture in the first welding state based on the impedance, the time delay and the insertion loss.

A cascade MosFet circuit design for variable gear switching using pulse width modulation (PWM) between electronic gears to achieve a smooth transition is disclosed. In an embodiment, in the system, there can be three separate stages of two or more switches from very low amperage to hundreds of amps that can be automatically selected within a chosen stage. The automatic switching can be programmed to be power (e.g., current) sensitive or can be both power and electronic gear sensitive as to cascade into the right MosFet combination for different gear settings and still select greater values for varying power levels. Such a smooth transition can allow the generator or motor using such cascade MosFet circuit design to operate more efficiently and / or more quietly.

A digital pre-distortion (DPD) module according to one embodiment of the present disclosure comprises: at least one memory for storing at least one look-up table (LUT) group including at least one LUT determined on the basis of characteristics of a plurality of power amplifiers; a plurality of bit concatenation circuits for extracting, on the basis of the number of bits allocated to each LUT, consecutive bits of data output from the memory; and a DPD circuit for identifying each LUT on the basis of data output from the plurality of bit concatenation circuits, determining a DPD model on the basis of each LUT, and performing, on the basis of the DPD model, pre-distortion on at least one power amplifier with respect to an input signal input into the at least one power amplifier.

The invention discloses a high-voltage power switch circuit for an intelligent fusion terminal switch power supply. The circuit comprises a voltage clamping circuit and an MOS tube cascade circuit. The voltage clamping circuit is connected in parallel between the DC bus voltage end and the grounding end, and forms a clamping voltage according to the first voltage and outputs the clamping voltage through the clamping output node. The MOS tube cascade circuit comprises a transformer and a cascade switch branch formed by connecting a first MOS tube and a second MOS tube in series, one end of the primary winding is connected with a first voltage, and the other end of the primary winding is grounded through the cascade switch branch; clamping voltage is connected to the grid electrode of the first MOS tube, grid electrode driving signals are connected to the grid electrode of the second MOS tube, and a voltage stabilizing diode is connected between the grid electrode and the source electrode of the first MOS tube in parallel. On-off is controlled through a grid driving signal, upper tube grid source driving is established under voltage limiting of a voltage stabilizing diode, controlled on-off of a primary side is achieved, dependence on a single ultrahigh-voltage-resistant MOS device is reduced, and the problems that model selection is limited and cost is high under high-voltage input are solved.

The present application discloses a carry logic circuit, a carry cascade circuit, and a chip. The carry logic circuit comprises Y stages of cascaded carry operation modules and a carry output module; each stage of carry operation module is used for receiving i pairs of arithmetic signals; a first-stage carry operation module is used for outputting a first-stage carry generation signal and outputting a first-stage carry propagation signal; an x th-stage carry operation module is further used for receiving a previous-stage carry generation signal and a previous-stage carry propagation signal, outputting an x th-stage carry generation signal, and outputting an x th-stage carry propagation signal; and the carry output module is used for receiving an initial carry signal, a Y th-stage carry generation signal, and a Y th-stage carry propagation signal, and outputting a first carry signal. The present application improves the carry operation performance of the carry logic circuit.

The utility model provides a circuit for realizing nozzle cascade based on an SATA (Serial Advanced Technology Attachment) line, and relates to the field of nozzle circuit diagrams.The circuit comprises an SATA port, a plurality of SATA-IN ports and a plurality of SATA-OUT ports, the SATA port is arranged in a main board, the SATA-IN ports and the SATA-OUT ports are respectively arranged in a head board, the SATA port is arranged in the main board, and the SATA-IN ports and the SATA-OUT ports are arranged in the head board. Coding switch control is arranged between the SATA port and the SATA-IN port, and coding switch control is arranged between the SATA-OUT port and the SATA-IN port, and coding switch control is arranged between the SATA-OUT port and the SATA-IN port. According to the utility model, the SATA-IN port and the SATA-OUT port are arranged in the head plate, two adjacent head plates can communicate with each other, a plurality of nozzles can be controlled to print at the same time, the circuit is simple, the manufacturing and maintenance cost is low, the shielding effect of the SATA wire is good, and the anti-EMC capability is improved fundamentally.

The invention discloses a cascade converter and a control method. The cascade converter comprises a first buck-boost cascade circuit and a second buck-boost cascade circuit. The first buck-boost cascade circuit comprises a first buck-boost circuit and a first coupling circuit; the second buck-boost cascade circuit comprises a second buck-boost circuit and a second coupling circuit; the input end of the first boost-buck cascade circuit is connected in series with the input end of the second boost-buck cascade circuit, the output end of the first boost-buck circuit is connected to the input end of the first coupling circuit, and the output end of the second boost-buck circuit is connected to the input end of the second coupling circuit. The output end of the first coupling circuit is connected with the output end of the second coupling circuit in parallel. By means of input series connection and output parallel connection, withstand voltage of a switching tube can be reduced, and the device has the advantages that device type selection is convenient, device characteristics are better, so that overall switching loss is reduced, power supply efficiency can be improved, and good economic and social benefits are achieved.

Provided A gate drive circuit includes: a first frame start signal line and a cascade circuit. The first frame start signal line is connected to a first input terminal of the cascade circuit, configured to transmit a first frame start signal to the cascade circuit in a first display stage. The cascade circuit includes shift registers. Each shift register is connected to a clock signal line. An output terminal of each shift register is connected to a writing module in a pixel drive circuit. The cascade circuit is configured to output first scanning signals stage by stage according to the first frame start signal and a clock signal from the clock signal line. The effective level of the first frame start signal in one period overlaps with a plurality of pulse signals of the clock signal. The first scanning signal includes a plurality of scanning pulse signals in one period.

The application relates to the technical field of high-speed electronic design automation simulation, and further relates to a via simulation method and system, a computer device and a storage medium. The method comprises the following steps: decomposing a multilayer via structure into multiple units, each unit comprising a cavity formed by a pair of plates and at least one via segment passing through the cavity; calculating an inter-plate impedance matrix of the cavity in each unit according to a finite element algorithm; calculating a coupling capacitance between the cavity and the via segment in each unit according to an analytical method; constructing multiple pi-type coupling circuit models according to the inter-plate impedance matrix and the coupling capacitance corresponding to each unit; cascading the pi-type coupling circuit models of each layer to obtain a multilayer via cascaded circuit model; and calculating scattering parameters according to the multilayer via cascaded circuit model. The method accurately and efficiently simulates a multilayer structure comprising vias, traces and an actual power ground plane, and realizes collaborative design of signal integrity and power integrity.

Described herein is a cascade circuit comprising a controller configured to provide a set of control signals each having a high or low level value, and having a data port, and at least two multiplexers. And at least two multiplexers in a cascade arrangement electrically connected to the controller, respectively, each multiplexer including: a plurality of transmission pins configured to transmit a plurality of transmission signals communicated to the outside, respectively; and an output pin in communication with the data port, the plurality of transfer pins being respectively coupled to the output pin via a multi-way switching element. The respective output pins of the at least two multiplexers are collectively electrically connected to the data port, and signal communication with the data port of the controller is switched between the respective output pins of the at least two multiplexers.

The invention discloses a low-noise amplifier and a receiving system. The low-noise amplifier comprises an input matching circuit, a primary circuit, an inter-stage matching circuit, a secondary circuit, an output matching circuit and a common biasing circuit, the input matching circuit is connected with the first-stage circuit and the common bias circuit, the inter-stage matching circuit is connected with the first-stage circuit and the second-stage circuit, the second-stage circuit is connected with the common bias circuit and the output matching circuit, the common bias circuit is connected with the power supply, and the power supply voltage is connected with the first-stage circuit and the second-stage circuit. For two-stage amplification circuits, namely a first-stage circuit and a second-stage circuit for amplifying signals, the overall area of a chip is effectively reduced by sharing an active bias structure of a bias circuit and reducing the number of components of a multi-stage amplification cascade circuit, so that the cost is reduced; and coupling and parasitic risks caused by factors such as layout and wiring of the components under a limited layout area are reduced.

The application relates to the field of advanced packaging technology of integrated circuits, and particularly relates to a manufacturing method of a standard power unit structure for embedded packaging. The method comprises the following steps: obtaining design parameters of all standard power units, performing patterned electroplating at one end of a copper plate to form a chip accommodating cavity and a positioning mark target, opening a blind groove in the copper plate to form an insulating area and a cutting area, dividing the copper plate into multiple copper base tables, retaining a layered structure of the copper plate as a connecting layer, mounting a chip to the chip accommodating cavity, performing whole-plate plastic packaging, windowing, laser drilling and metallization, forming interconnection vias and top external vias, manufacturing a rewiring layer, forming a half-bridge circuit, a full-bridge circuit, a cascade circuit, a multi-core series circuit, a multi-core parallel circuit or a single-core circuit, and removing the connecting layer to cut to obtain a standard power unit product. The application can batch-manufacture standard power units with high-efficiency heat dissipation function and different circuit structures including a multi-core series structure.

The application discloses a kind of based on LC cascade circuit's power cable broadband impedance physical simulation method and device, belong to power cable state diagnosis technical field.The method is replaced by LC cascade circuit equivalent to replace entity cable, accurately reproduces the broadband impedance characteristic of different voltage grades, different length power cable of 10kV~500kV.Detailed steps include: determining cable unit length distribution parameter, calculating cable basic characteristic parameter, determining LC simulation circuit unit number and lumped parameter, establishing LC cascade circuit model and setting work frequency band.The application greatly reduces the cost and land requirement of experimental platform, can construct standardized cable simulation platform, supports large-scale personnel practical operation training, provides unified calibration reference for instrument performance test, and has significant economic and social benefits.

The invention relates to a battery pack self-heating device and a motor driving system comprising the same. The device comprises a motor; each power unit comprises an input pin, an output pin and a cascade circuit formed by connecting at least two cascade modules in series, and each cascade module comprises a battery module and a power conversion bridge formed by a plurality of power switches; the first end of the master control switch is connected to a neutral point of the motor, and the second end of the master control switch is connected to the common contact; and a control chip configured to switch off the master control switch in a first working mode and control the on-off of each power switch in the plurality of power units according to a predetermined duty ratio, and to switch on the master control switch in a second working mode and control the on-off of each power switch in the plurality of power units according to a predetermined duty ratio. And the charging operation and the discharging operation of the battery module in the corresponding power unit are periodically switched by controlling the on-off of each power switch in the corresponding power unit.

The invention provides a half-bridge cascade circuit with a current sampling function and a corresponding circuit board, a digital-to-analog conversion chip performs digital-to-analog conversion on a first PWM digital signal to generate a first analog signal, and a voltage conversion chip performs voltage conversion on the first analog signal by taking the voltage of a switch node as a reference. And the integrated chip performs digital-to-analog conversion on the second PWM digital signal to generate a second analog signal, the signal output pin outputs the second analog signal, and the integrated chip generates a current sampling signal based on the power supply voltage generated by the power supply and the second analog signal. The second analog signal can control the first lower bridge arm field effect transistor to be switched on or switched off, and the first analog signal can control the first upper bridge arm field effect transistor and the second upper bridge arm field effect transistor to be switched on or switched off. The half-bridge cascade circuit can adjust the voltage of the switch node based on the on or off time of the first upper bridge arm field effect transistor and the second upper bridge arm field effect transistor and based on the on or off time of the first lower bridge arm field effect transistor.

The invention discloses a control method, a control device and a switching power supply, the control method is applied to a buck-boost cascade circuit in a current feed mode, and the buck-boost cascade circuit comprises a pre-stage buck-boost circuit and a post-stage isolation switching power supply circuit; the pre-stage buck-boost circuit comprises a main switch tube, a synchronous switch tube and an inductor, and adopts a connection mode of a buck circuit; the rear-stage isolation switch power supply circuit comprises a primary side switch circuit, a transformer and a secondary side switch circuit; the primary side switching circuit is a push-pull or full-bridge circuit and at least comprises a first primary side switching tube and a second primary side switching tube which are alternately conducted, and the first primary side switching tube and the second primary side switching tube have first common conduction time; the secondary side switching circuit is a full-bridge rectifying circuit and comprises a first bridge arm low-potential end switching tube and a second bridge arm low-potential end switching tube; the control method comprises the step that after the first common conduction time is over, the low-potential end switch tubes of the first bridge arm and the second bridge arm have second common conduction time. The cost and the size of the power supply system are reduced while the reliability is met.

An electromagnetic door lock control circuit and apparatus. The electromagnetic door lock control circuit comprises: a power supply circuit, a cascade circuit, a sensing and identification circuit, an electromagnet drive circuit, and an MCU main control circuit, which is electrically connected to the power supply circuit, the cascade circuit, the sensing and identification circuit and the electromagnet drive circuit. The electromagnetic door lock control circuit can not only detect the opening and closing of an electromagnetic door lock, but can also detect, by means of cascade control, whether one or more electromagnetic door locks on a production line have been opened without authorization, and send an anomaly signal to an upper computer for identification, such that the upper computer knows which device's electromagnetic door lock is not closed or is malfunctioning, thereby preventing the occurrence of production accidents caused by the unauthorized opening of the electromagnetic door lock. The electromagnetic door lock control circuit is arranged in the electromagnetic door lock control apparatus.

The invention discloses an on-chip dual-polarization eight-beam power division network, and belongs to the technical field of power divider network design. The power division network comprises two mutually independent power divider networks, and a three-stage one-to-two power divider cascade circuit is arranged in each power divider network. In the transmitting mode, an input signal is equally divided through two independent 1: 8 power divider networks, and in the receiving mode, the input signal is combined through two independent 8: 1 power divider networks. Due to the fact that the power division network needs to ensure that the output power and the phase of each path are consistent, the design adopts the network layout of the mutually nested power dividers, the power dividers can have independent path optimization and insertion loss and reflection optimization in channels, and on the premise that the layout network is simplified and the layout compatibility is improved, the power distribution efficiency is improved. And the power and phase consistency of the power divider network is better realized. According to the invention, the return loss effect is good, the power division effect is good, and the on-chip space and cost are reduced.

The application provides a battery plug-in box converter and an electrochemical energy storage conversion system, and belongs to the field of electrochemical energy storage. The battery plug-in box converter comprises a main control unit, a DC / DC conversion circuit and a high-speed communication interface connected to the main control unit respectively; the positive and negative poles of one end of the DC / DC conversion circuit are connected to the output positive and negative poles of a battery plug-in box respectively; and the positive and negative poles of the other end of the DC / DC conversion circuit are connected to the positive and negative poles of a cascade circuit respectively. The short board effect caused by the fact that a certain battery or battery plug-in box in the electric pile reaches the cut-off voltage or fails can be eliminated by using the application, and the charge and discharge capacity and the charge and discharge efficiency are improved.