Abstract: A frequency detector detects a system frequency from an AC voltage on an AC power line to which a power conditioner performing system interconnection of a distributed power supply is connected. A power converter is configured to inject lead reactive power or delay reactive power into the AC power line. A controller controls reactive power output from the power converter to output the lead reactive power in response to an increase in the system frequency while outputting the delay reactive power in response to a decrease in the system frequency.

Abstract: In an uninterruptible power supply apparatus, AC current, which includes a feedback component having a value corresponding to deviation between terminal-to-terminal voltage of a capacitor and reference voltage, and a feed forward component obtained by multiplying load current by a gain, is passed into a converter such that the terminal-to-terminal voltage of the capacitor becomes the reference voltage. The gain is set to a first gain in an iverter power feed mode and a bypass power feed mode, and the gain is set to a second gain smaller than the first gain in a switching period of switching between the inverter power feed mode and the bypass power feed mode, to prevent the terminal-to-terminal voltage of the capacitor from exceeding an upper limit voltage in a lap power feed mode.

Abstract: A control device is a control device of a power conversion device, and includes a conversion value calculation unit that acquires a current value of a current flowing in an alternating-current capacitor connected to a capacitor circuit in an output circuit on an alternating-current side of an inverter circuit and performs conversion of the current value to obtain a predetermined conversion value, and a failure detection unit that compares the conversion value obtained by the conversion value calculation unit and a predetermined determination value to be used in failure detection to detect a failure of the alternating-current capacitor.

Abstract: A motor drive system of the embodiment includes a power converter, a state detector, a frequency calculator, a frequency correction command generator, a drive amount limiter, and a speed controller. The power converter drives a motor by PWM control. The state detector detects a drive state of the motor. The frequency calculator detects a size of a specific frequency component which fluctuates according to the drive state by using an index value indicating the drive state. The frequency correction command generator generates a correction command of a carrier frequency used for the PWM control on the basis of a detected result of periodic fluctuation of the drive state. The drive amount limiter limits a drive amount of the motor.

Abstract: A discharge unit of an embodiment includes a drain pan, a discharge portion having an insulation property, a grounded drain piping, and a liquid separation part having an insulation property. The drain pan receives a liquid. The discharge portion is connected to the drain pan and drains the liquid remaining in the drain pan. The liquid separation part prevents the liquid from flowing continuously between the discharge portion and the drain piping.

Abstract: A power conversion device with a three-level TNPP circuit, includes: a voltage detection unit; a test pulse output unit that outputs a test pulse to an inner switching device connected in a forward direction from the DC neutral point to an AC output terminal when the voltages detected by the voltage detection unit rise and exceed a predetermined threshold; and a determination unit that determines, when the test pulse output unit outputs a test pulse to the inner switching device connected in the forward direction from the DC neutral point to the AC output terminal, upon drop in the voltage between the DC neutral point and the DC negative electrode detected by the voltage detection unit, that an outer switching device connected to the DC negative electrode has a short circuit failure.

Abstract: Inside a heating space of a heating chamber, a first heating treatment of moving a substrate along a substrate moving direction is performed by a first conveyor. After that, first conveyance processing of moving the substrate along a conveying direction is performed by a second conveyor. At this time, source mist is sprayed on the substrate by first thin film forming nozzles. Subsequently, second heating treatment is performed by a third conveyor. After that, second conveyance processing is performed by a fourth conveyor. At this time, source mist is sprayed on the substrate by second thin film forming nozzles.

Abstract: A power conversion device includes: a power conversion circuit connected to a direct-current power supply and a power system and configured to perform conversion between direct-current power and alternating-current power; a phase-locked loop circuit configured to output a phase instruction value based on a system alternating-current voltage phase of the power system; and a control circuit configured to control the power conversion circuit based on the phase instruction value from the phase-locked loop circuit. The phase-locked loop circuit includes: a phase difference calculation section configured to calculate a phase difference in a predetermined cycle, the phase difference representing a deviation of the phase instruction value from the system alternating-current voltage phase of the power system; a phase difference correction section; and a phase instruction value generation section configured to output the phase instruction value based on an output of the phase difference correction section.

Abstract: An object of the present invention is to provide a SCADA web HMI system that can reduce a load for processing an alarm signal in a large-scale system. An HMI server apparatus performs buffering processing and alarm filtering processing. In the buffering processing, in a case where a received block data includes a set of alarm signals, at least the set of alarm signals included in the block data is temporarily stored in an alarm buffer memory. In the alarm filtering processing, the set of alarm signals stored in the alarm buffer memory is taken out for every second period that is longer than a first period, and the alarm signal having a value varied from a previous value is extracted from the taken-out set of alarm signals.

Abstract: A distributed-power-supply power conversion system includes a plurality of power inverters configured to invert DC power to AC power; and a control device configured to select at least one power inverter from the plurality of power inverters as a power inverter used for testing, and configured to perform an energization test of the power inverter used for testing in a state where an AC side of the power inverter used for testing is disconnected from a system, and is connected to an AC power supply device and to a load bank, and a voltage on the AC side of the power inverter used for testing is established. The distributed-power-supply power conversion system can perform an energization test of a power inverter before a system receives power.

Abstract: A bus connection system according to an embodiment of the invention includes a control device that is connected to one end of a first bus and operates as a first node, and a bus connection device that is located between another end of the first bus and a first battery pack operating as a second node and between the other end of the first bus and a second battery pack operating as the second node. The bus connection device includes a first switch located between the first battery pack and the other end of the first bus, a second switch located between the second battery pack and the other end of the first bus, and a contact switching circuit sequentially opening and closing the first switch and the second switch.

Abstract: A power conversion apparatus capable of supplying a required reactive power while dynamically changing a dead band near 0 reactive current and maintaining a balance of DC voltage is provided. The power conversion apparatus including a three-level converter, a PWM controller for the three-level converter, an input current detector of the three-level converter, a coordinate converter that converts the current into a d-axis and q-axis current feedback, the reactive power control unit that controls a reactive power and outputs an reactive current reference, a d-axis current control unit having a dead band part for setting the d-axis current reference with hysteresis characteristics in the q-axis current feedback, and outputs the d-axis voltage reference, a q-axis current control unit that outputs a q-axis voltage reference based on the q-axis current reference, an inverse coordinate converter that outputs a three-phase AC voltage command based on the d-axis and q-axis voltage reference.

Abstract: A drawing creating device generates HMI configuration data for a system monitoring screen from a network configuration diagram drawn by drag-and-drop operation. An HMI server device executes a system monitoring process by applying HMI configuration data to a predetermined server runtime library, and transmits a display signal according to the communication status of a monitored device. An HMI client device draws the system monitoring screen on a web browser and changes the display statuses of the parts positioned on the system monitoring screen according to the received display signal. According to the present invention, the system monitoring function of an industrial plant can be implemented in a non-programmable graphical manner.

Abstract: In preset calculation, a plurality of cooling banks are set to be feedforward or feedback banks, and each of water injection amounts in these banks is calculated. In cooling history management, a recalculation position for re-executing the feedback calculation is set. In feedback calculation, a temperature correction value for compensating a delay due to a conveyance time period from a position of the feedback bank to a position of a delivery side pyrometer, and a response delay of the feedback bank is calculated, when a segment reaches the recalculation position. In the feedback calculation, each of water injection amounts in the feedback banks that is calculated in the preset calculation is changed for each of segments based on a delivery side temperature target value, a delivery side temperature actual value calculated for each of the segments, a delivery side temperature prediction value that is recalculated, and the temperature correction value.

Abstract: A SCADA web HMI system dynamically distributes server connection priority lists from web HMI servers to HMI clients in accordance with order of assignment which takes load balancing into account. As a result, preliminary settings associated with connection priority do not need to be made on the HMI clients. Also, since the server connection priority lists are assigned to the HMI clients in accordance with the order of assignment which takes load balancing into account, the numbers of clients connected to the individual web HMI servers are equalized and the load balancing can be ensured. The SCADA web HMI system can reduce the operating costs necessary in client settings while ensuring redundancy and load balancing of servers.

Abstract: Each of a plurality of unit converters includes: a main circuit; a control circuit that controls the plurality of switching elements according to a control signal received from the controller; a power supply that lowers a voltage of a first capacitor to generate a power supply voltage and supplies the power supply voltage to the control circuit; and a current-limiting resistance circuit having a variable resistance value and disposed between the main circuit and the power supply. The power supply includes a second capacitor, an overcharge suppression circuit, a power supply circuit, and a controller. The controller includes: an overcharge suppression control circuit that controls the overcharge suppression circuit in accordance with a magnitude of a voltage of the second capacitor; and a resistance switching circuit that changes a resistance value of the current-limiting resistance circuit in accordance with a magnitude of a voltage of the first capacitor.

Abstract: An external storage device for a control apparatus of a power conversion system to which data from a power conversion system can be written even by a program small in size. The external storage device for the control apparatus of the power conversion system includes: a plurality of file storage areas each configured to store data from the power conversion system; and a file management area configured to manage data for setting a format not using a file system applied to a terminal apparatus, as a format for storage of the data in the plurality of file storage areas.

Abstract: A power supply includes a second capacitor, an overcharge suppression circuit, a power supply circuit, and a controller. The controller includes: an overcharge suppression control circuit that controls the overcharge suppression circuit in accordance with a magnitude of a voltage of the second capacitor; and a resistance switching circuit that changes a resistance value of the current-limiting resistance circuit depending on whether a gate block state occurs or not and in accordance with a magnitude of the voltage of the first capacitor. In the gate block state, each of the switching elements is fixed in a non-conductive state.

Abstract: A power conversion device includes an inverter, a current detector, a frequency analysis processor, a storage, a determination unit, a reference rotational rate change unit, and a rate controller. The determination unit determines a frequency at which a signal component having a magnitude exceeding a prescribed value has been detected among frequency components of a load current, generates restriction information for excluding a reference rotational rate for a rotational rate corresponding to the detected frequency based on a determination result after the determination, and causes the storage to store the generated restriction information. The reference rotational rate change unit changes a reference rotational rate of an electric motor so that mechanical resonance of the detected frequency is avoided based on the stored restriction information. The rate controller controls a rotational rate of the inverter using the changed reference rotational rate.

Abstract: When a general-purpose operation part (22, 23) is hidden by a window part (24), it becomes hard for an operator to visually check an association state between a field device (10A, 10B) and a hardware switch (3). If such a display state has occurred, an HMI server (5) stops a health check signal which is being output to a PLC (6). The PLC (6) detects the stop of the health check signal and forcibly cancels the association state between the field device (10A, 10B) and the hardware switch (3). Thus, a human error can be prevented.