摘要:
Embodiments of the present disclosure relate to a method, apparatus for operating a conduction assembly, a start device, and a computer-readable medium. The conduction assembly is coupled between an AC power supply and an inductive load, and comprises a first switch device and a second switch device which are in anti-series connection, the first switch device comprises a first body diode in anti-parallel connection with the first switch device, and the second switch device comprises a second body diode in anti-parallel connection with the second switch device. The method comprises: conducting the conduction assembly at a first conduction angle in a first cycle; conducting the conduction assembly in a second cycle at a second conduction angle that is greater than the first conduction angle, wherein in the first cycle and second cycle, a turn-off timing of the first switch device or the second switch device in anti-parallel connection with the first body diode or second body diode having a conduction direction the same as a current direction is determined based on the current flowing through the conduction assembly. The method proposed here may reduce the power loss of the soft start circuit.
摘要:
A semi-controllable device driving method and apparatus and a hybrid device of the present disclosure belong to the electrical field, and are particularly a driving method, with no driving dead zone or with an extremely small driving dead zone, that is applicable to a semi-controllable device such as a thyristor; a semi-controllable driving apparatus, with no conduction dead zone or with an extremely small conduction dead zone, that is applicable to a driving loop of a semi-controllable device such as a thyristor; and a hybrid device with no conduction dead zone or with an extremely small conduction dead zone. In the semi-controllable device driving method, a voltage detection switch is used; an input end of the voltage detection switch is connected to two ends of a semi-controllable device that needs to be driven; the voltage detection switch is connected, in series, in a driving loop of the semi-controllable device; the voltage detection switch is turned on when a potential difference at the two ends of the semi-controllable device is not greater than an on-state voltage of the semi-controllable device; and the voltage detection switch is turned off after detecting that the semi-controllable device is turned on. The present disclosure has an advantage of no driving dead zone or an extremely small driving dead zone.
摘要:
Driver circuit in which a capacitor (4), in a manner controlled by a switch control device (9) which is connected downstream of a current measuring device (8), is charged to a reference voltage (Ur) by means of a charging current (Ic2), and the charged capacitor is discharged in an oscillating manner via an inductor coil (1), wherein the discharging operation is terminated when the current (Ia) through the inductor coil has passed through an entire oscillation period or several oscillation periods, wherein a first controllable switch (5) is connected in series between a first non-reactive resistor (6) and the first capacitor (4) in one of two input paths. Furthermore, a second controllable switch (7) and a fourth controllable switch (14) are connected into two output paths, and a second non-reactive resistor (13) is connected between a second connection (X2) of the inductor coil (1) and a connection for Na reference potential (Um). The current measuring device (8) is connected between the fourth controllable switch (14) and the first capacitor (4).
摘要:
A switching device is provided for disconnecting or connecting an electric machine, a converter or a plurality of electrical loads supplied with AC power from a power supply and controlled by a control unit. The switching device includes a current sink and at least one mechanical switch in the switching device are arranged in a circuit. The current sink is arranged, upon receipt of a signal, to close and sink the current, and the at least one mechanical switch is arranged to open and break the current on receipt of a signal to open supplied to the electric machine when the current load is at or close to zero. A method and a computer program for carrying out the method are described.
摘要:
Device and method for generating brief strong current pulses in a coil for generating magnetic field pulses which according to the electromagnetic induction principle induce stimulation currents in the body tissue triggering an action potential of the nerve and/or muscle cells, where the coil is positionable close to the body tissue to be stimulated so that its magnetic field passes through the body tissue, and where the device comprises a power generating unit that can generate a freely selectable temporal course of the current through the coil during the current pulse. A method for determining an optimized temporal course of a brief strong current pulse through the coil, where the temporal course of the current pulse is calculated using a method which numerically simulates the electrical behavior of nerve and/or muscle cells and the coil and optimizes the course of the current pulse regarding at least one parameter, or which by means of stimulating the nerve and/or muscle cells with predetermined current pulses optimizes the temporal course of the current pulse regarding at least one parameter and therefrom determines essential parameters of nerve and/or muscle cells.
摘要:
A method and a circuit for detecting an overheating of an electronic switch of power supply of a load by an A.C. voltage, in which a voltage representative of the temperature in the vicinity of the switch is compared with a threshold, the result of this comparison being sampled at frequency corresponding to an even multiple of the frequency of the A.C. power supply voltage, to provide a signal indicative of the fact that a temperature threshold has been exceeded.
摘要:
A method and a circuit for controlling at least one thyristor constitutive of a rectifying bridge with a filtered output, including closing the thyristor when the voltage thereacross becomes greater than zero, and making the gate current of the thyristor disappear when the current therein exceeds its latching current.
摘要:
A bidirectional switch, including a first bidirectional switch between two power terminals of the switch, a low-voltage storage element between a first power terminal and a control terminal of the switch, and a control stage adapted to cause, upon each halfwave beginning of an A.C. supply voltage applied between the power terminals and when the switch is on, the charge of the storage element with a biasing depending on the sign of the halfwave.
摘要:
A zero crossing control circuit of a bidirectional switch including two transistors of complementary types connected in parallel between the gate of the bidirectional switch and the main reference terminal of the bidirectional switch, the gate of the bidirectional switch being connected to a control source via a first resistor, and each of the control terminals of the transistors being connected to the second main terminal of the bidirectional switch via a second resistor of high value, a zener diode being interposed between the second resistor and each of the control terminals according to a biasing adapted to turning on each of the transistors when the zener threshold is exceeded.
摘要:
A control arrangement and method is provided for a power electronic system configured as a high-speed source-transfer switching systems (HSSTSS). The HSSTSS supplies an electrical load with alternating current from either a first source or a second source via respective first and second solid-state switches. The HSSTSS also includes a controller that samples the voltage waveforms of each of the first and second sources to detect when transfer between the sources is desirable, e.g. outages or voltage that is either too low or too high. The controller provides appropriate control signals to control operation of the solid-state switches and transfer supply of the load therebetween. The control arrangement avoids undesirable current flow between sources via a comparison of the voltages of the sources and current in the outgoing source, i.e. a polarity comparison to ensure that the current that will flow in the incoming source after transfer will be in opposition to the current flowing in the outgoing source before transfer. Thus, the transfer is delayed until the polarity comparison is satisfied. Additionally, the control arrangement minimizes undesirable transfer delays by establishing appropriate transfer conditions before issuing control signals to perform the transfer between sources, i.e. the transfer to turn on the incoming switch is delayed until after appropriate conditions establish that the outgoing source is off or can be effectively turned off. One form of appropriate conditions include the establishing of forced commutation conditions, preferably established by the incoming source voltage differential and the outgoing current being of the same polarity such that the voltage differential across the solid-state switch that is being turned on is sufficient to establish an initial change in current flow in opposition to the current flow in the solid-state switch to be turned off. The appropriate forced commutation is established by the voltage differential between the two sources being of sufficient magnitude to force the outgoing current to zero. Additionally, under certain conditions, the transfer is accomplished by awaiting the next current zero.