134 results about "Thyristor drive" patented technology

The invention relates to a submodule circuit board for a dynamic analog test for simulating a high-capacity modularized multi-level modular converte. A plurality of independent MMC (Multi-level Modular Converte) submodules reducing parameters according to an equitime constant method with a voltage level less than 50V are arranged on the circuit board; the plurality of submodules are completely independent and are of a series relationship; and the submodule comprises chips for controlling, coding and decoding, an optical fiber channel, a main circuit (provided with a capacitor and two IGBTs (insulated gate bipolar transistor) of an upper-lower series structure connected with the capacitor in parallel, a bypass switch connected with the lower IGBT in parallel, and a thyristor used for protecting the IGBTs and the capacitor and connected with the lower IGBT in parallel), an IGBT and thyristor drive circuit, a capacitance voltage sampling circuit, and a circuit board isolating power source which are respectively independent.

The invention provides a combined type arc-free alternating-current (AC) contactor with the function of thyristor fault diagnosis. The combined type arc-free AC contactor comprises an AC contactor body, parallel shunt branch circuits and a detection control device, wherein the parallel shunt branch circuits are respectively connected to the two ends of each three-phase main contact of the AC contactor body in parallel; the parallel shunt branch circuit of each phase comprises a current detection unit, a bidirectional thyristor, a thyristor self-check relay, a thyristor self-check resistor and an electromagnetic relay; the detection control device comprises a three-phase voltage detection unit, an A-phase voltage zero-crossing detection unit, a three-phase current detection unit, an A-phase current zero-crossing detection unit, a solenoid excitation unit, a thyristor drive unit, an electromagnetic relay drive unit, a current detection unit, a resistance-capacitance buck power supply and a microcontroller. The combined type arc-free AC contactor is used for frequently connecting or disconnecting an AC main circuit, and the generation of electric arcs during each action of the contactor is inhibited through the instant current shunting of power electronic devices, so that the erosion to the main contacts of the contactor caused by the electric arcs is reduced greatly.

The invention belongs to the field of electrical technology and discloses a phase sequence self-adaption trigger circuit of a three-phase fully-controlled rectifier induction heating power supply. The phase sequence self-adaption trigger circuit is connected in series between a three-phase alternate current and a three-phase full-bridge thyristor drive axle and mainly comprises a phase sequence judging circuit, a three-phase synchronous signal additional phase shifting and phase sequence gating circuit, a thyristor three-phase trigger pulse phase shifting circuit and a three-phase trigger phase gating and output circuit. After a three-phase switching-in phase sequence of the induction heating power supply is judged by the phase sequence judging circuit, a suitable three-phase rectifier trigger pulse is generated by the three-phase synchronous signal additional phase shifting and phase sequence gating circuit and is sent into the thyristor three-phase trigger pulse phase shifting circuit to generate phase shifting; and the three-phase rectifier trigger pulse which is subjected to phase shifting is sent to the three-phase trigger phase gating and output circuit to drive a thyristor of the three-phase full-bridge thyristor drive axle. According to the invention, the random switching-in of a line sequence of three phases of the induction heating power supply is implemented and the phase sequence self-adaption trigger circuit has the characteristics of simple structure and low cost.

A generation method of the driving waveform of a thyristor rectifier comprises the following steps that power grid voltage signals are collected, and a phase-locked loop follows power grid voltage and outputs a sinusoidal signal the same with the power grid voltage in direction; a reference waveform corresponding to a thyristor drive bridge arm is obtained by calculation according to the sinusoidal signal; the difference between the actual zero time of the reference waveform and the corresponding PWM break time is calculated; according to the time difference, the PWM break time is adjusted, so that a PWM control wave and the reference waveform are synchronous; according to the PWM control wave, a double-narrow pulse drive wave is output to control upper and lower thyristors on the corresponding thyristor drive bridge arm to work. According to the scheme, high-precision PWM control wave emission is achieved, breakover time control on the thyristors is more accurate, and working precision and stability of the thyristor rectifier are improved effectively.

The microcomputer controlled phase shift triggered voltage stabilizer for permanent magnet generator includes circuit of operational power supply, circuit for collecting three-phase voltage and frequency of motor, setting circuit for voltage regulation and feedback, circuit of single chip, and thyristor drive circuit etc. Using calculation function of single chip implements closed loop control of software, and turns on three-phase shift triggering pulse to trigger thyristor. Built in or configured in permanent magnet generator, voltage stabilizer outputs stable DC voltage. Self-starting mode is adopted in the invention. Thus, generator can output stable voltage without need of external voltage so as to prevent phenomena of no outputted voltage if no external DC voltage (for ex. in excitation type motor) from occurring. Advantages are: raised reliability, reduced maintenance work, good load characteristic, quick adjustment and high precision of output voltage.

The invention provides a passive filtering device and method with a fault arc detection function. The device comprises a voltage sensor, a current sensor, a sampling circuit, a signal processing circuit, a master control MCU, an arc fault alarm circuit, a switch quantity isolation and output circuit, a thyristor driving circuit, a thyristor switch, a capacitor and an inductor. The current detecting part of a failed arc and a current detection part of a passive filtering are shared, a same detection signal is used, a common master control unit is used to carry out fault arc analysis and harmonic content calculation, thus the device can be sampled before of the filtering of the failed arc characteristic current, and the accurate detection of a failed arc is ensured. According to the fault arc detection method, the judgment result of a current difference parameter is used as a premise, a harmonic ratio and change rate are used to judge the failed arc, the interference of a nonlinear load can be effectively eliminated, four judgment means are used to carry out judgment at the same time, and the failed arc is accurately detected.

Charging time of a capacitor is shortened while avoiding erroneous firing due to distortion of a power supply voltage and sustaining an inrush current at a constant level. In the charge control method of a capacitor in a thyristor converter comprising a thyristor for rectifying an AC voltage, a CPU delivering an on/off control signal to a thyristor driver for driving the thyristor, a voltage detection sensor for measuring the AC voltage and the capacitor charging voltage, and the capacitor connected with a DC circuit, the AC voltage and the capacitor charging voltage are measured by means of the voltage detection sensor, differential voltage between the firing phase voltage of the thyristor and the capacitor charging voltage is determined, and the thyristor is fired only when the firing phase voltage of the thyristor becomes lower than a specified voltage determined from the differential voltage.

The invention discloses a phase-controlled type AC-AC (alternating current) frequency converter real-time trigger pulse generation system and method thereof. The system comprises a voltage and current measurement unit, a signal conditioning unit, a pulse real-time generation and coding unit, a serial port communication unit, an interrupt signal source, a frequency converter logical judgment unit,a synchronous parallel unit, a pulse decoding unit and a thyristor driving unit which are all interconnected, wherein a system power supply unit is connected with the signal conditioning unit, the series port communication unit, the pulse real-time generation and coding unit, the frequency converter logical judgment unit, the synchronous parallel unit and the pulse decoding unit through power lines. The method comprises: the phase-controlled type AC-AC (alternating current) frequency converter real-time trigger pulse generation system adopts a multi-pointer method to realize the real-time generation of pulse, and also can reduce the direct current component and subharmonic component of the output voltage. Therefore, the system can be applied to all kinds of high-power AC transmission systems including frequency dividing wind power generation systems.

The invention relates to a resistance welding constant-current control device. The device is characterized in that a sensor is arranged on a welding electrode and is connected with a welding current synchronous circuit; a pedal switch and an electromagnetic valve are separately connected with an optoelectronic isolating circuit; and the welding current synchronous circuit, a net voltage synchronous circuit, a tablet computer, a silicon controlled thyristor drive circuit and the optoelectronic isolating circuit are separately connected with a SCM control unit circuit. The current value collected by the device at a wielding point is calculated by a SCM to compare the actual current value with the defined value, the silicon controlled thyristor control angle of the next welding cycle can be adjusted according to the current power factor, and the constant current electrical resistance welding value can be obtained. The obtained good control effects are as follows: when the net voltage changes between 340V to 420V, the fluctuation of the constant-current control accuracy is less than +/-1%; and the stability and reliability of the long-term operation of the device are high.

Disclosed is a thyristor contactor current detection device, which comprises a display panel and a mainboard connected with each other, wherein the mainboard is provided with a microprocessor; the microprocessor is connected with modules including a thyristor driving circuit, a thyristor status detection circuit, a current detection circuit, a power supply circuit, a fan driving circuit, a starting control signal detection circuit, a silicon controlled rectifier status indicating lamp, a temperature detection circuit, an overtemperature fault indicating lamp, a starting DO output and a fault DO output; the current detection circuit is connected with a current detection device for detecting a current of a rotor coil; the thyristor driving circuit and the thyristor status detection circuit are connected with a thyristor module for controlling the switching on and off of the rotor coil; the current detection device comprises an outer shell which is internally provided with a hollow coil wound on an insulating support; and the coil is used for being threaded by a conductor, and the coil comprises a connector which is used for being connected with a circuit board for outputting an induced voltage.

The present invention discloses a thyristor fault detection system and method. The system comprises: a thyristor drive control signal output module configured to output drive signals to a thyristor after control signals are received; a thyristor drive signal sampling module configured to collect the drive signals; a thyristor output voltage sampling module configured to collect a first output voltage of the thyristor when there are the drive signals and collect a second output voltage when there is no a thyristor; and a processing module configured to output the control signals and determine the state of the thyristor according to determination of whether there are the drive signals or not and determination of whether there is the first output voltage and/or the second output voltage. Thethyristor fault detection system and method can accurately and effectively detect whether the thyristor has faults or not to facilitate later maintenance of the thyristor and a device where the thyristor is located so as to improve the safety of the thyristor and the device where the thyristor is located.

Disclosed is a converter controlled generator. The generator converts a direct current outputted from a converter constituted of semiconductor rectifying elements for rectifying an output of a magnet generator into an AC. The conduction of thyristors is determined by a thyristor drive unit to control the voltage output of the converter to a target voltage level. The target voltage level is set to a positive value corresponding to the speed of the generator. The target voltage level is lowered when the generator is operated at a lower speed range and elevated when at a higher speed range. Accordingly, the output of the magnetic generator is increased substantially in proportion to the speed.

The invention discloses a power supply control device for a polycrystalline silicon reduction furnace, which comprises a voltage current module, a temperature sensing module, a digital filtering module, a phase tracking module, an input and output module, a control module, a light triggering module, a field bus module, a thyristor driving module and an HMI (Human Machine Interface) module. The voltage current module changes high voltages and large currents on silicon rods into analog signals of less than 5V; the temperature sensing module changes temperatures of the silicon rods of the original furnace into analog signals of less than 5V; high-frequency interference signals are filtered from the analog signals by the digital filtering module and the sampling is carried out to generate digital signals which can be identified by a computer; the control module implements a control strategy according to the digital signals; the control on the currents of the silicon rods and the conversion of a connection method are implemented by the light triggering module or the input and output module; and the thyristor driving module can directly drive a high voltage primary part and is isolated by optical fibers and a lowe voltage part. The invention solves the unbalance problem of a parallel loop of the power supply control device for the reduction furnace.

The invention relates to the technical field of the protection of a storage battery, and discloses an overtemperature warning device for the storage battery and an overtemperature warning method for the storage battery. The warning device comprises a temperature detecting and controlling circuit, an executing mechanism and an acousto-optic warning circuit, wherein the temperature detecting and controlling circuit is formed by the means that a temperature detecting circuit is connected with a temperature controlling circuit, and the temperature controlling circuit is connected with the executing mechanism and the acousto-optic warning circuit. The overtemperature warning method comprises the following steps of: magnifying an electric signal of an electric contact temperature gauge Q by a transistor V1 when the temperature of the storage battery is increased or exceeds a set temperature value 40 DEG C, triggering a thyristor VT, driving a relay K to work, and triggering the acousto-optic warning circuit and the executing mechanism to work. The invention can overcome the faults that the inner part of the storage battery is heated, a clapboard is damaged, and an inner circuit board falls off since the charging time is overlong; and the accident potential can be eliminated in a budding status, the safe and reliable running of a direct-current source of a power system transformer substation can be guaranteed, and the device and method provided by the invention have the characteristics of being wide in applicable scope, simple in circuit, economical and applicable.

The invention provides a thyristor detecting method for a semiconductor motor dicing resistance controller. A main board is arranged; and a display board is arranged on the main board. A microprocessor and an acceleration controller are arranged at the main board; the microprocessor is connected with a power source and commercial power is provided for the microprocessor through the power source; and a fan driving circuit is connected to the microprocessor and the microprocessor is connected with and controls a fan through the fan driving circuit. A startup control signal detecting module is arranged at the microprocessor; the microprocessor is connected to the acceleration controller through a thyristor driving circuit; the acceleration controller is connected to the microprocessor througha thyristor state detecting module; and the acceleration controller is connected to the microprocessor through a voltage detecting circuit. According to the invention, a forward control input signaland a reverse control input signal are inputted simultaneously without conduction, so that simultaneous conduction is avoided and thus a sending short-circuit risk is prevented. Moreover, the accelerated contactor control is realized and the quality of an internal silicon controlled rectifier is measured additionally.

The invention discloses a lossless thyristor driving circuit, and relates to the technical field of thyristor driving circuits. The lossless thyristor driving circuit comprises a thyristor Qa, a resistor R2, a rectifying diode D1, triodes Q1-Q3, diodes D2-D4, a resistor R1, resistors R3-R4, a capacitor C1 and a transformer T, wherein lossless driving is completely realized on the primary side of the transformer in the driving circuit. Compared with a lossy driving circuit (Fig. 2), the driving circuit is additionally provided with a VCC2 power supply of which the value is lower than that of VCC1. The VCC1 is used for providing peak driving current for the thyristor, and the VCC2 is used for providing platform driving current for the thyristor. The VCC2 can be obtained by using the VCC1 and a simple switch step-down chip. Through the driving circuit, the driving circuit loss, the demand of power supply power, the driving cost and the temperature of the driving circuit are lowered effectively, the area of a thyristor driving plate is reduced, and the reliability of the driving circuit is improved.