Abstract: Multipliers 21a and 21b output values, which are obtained by multiplying a total drive command value Es by first and second gains G1 and G2, respectively, as first and second drive command values E1 and E2. Controllers 23a and 23b control first and second actuators (motors) 5 and 7, respectively, on the basis of the first and second drive command values. The detection values of the drive amounts of the actuators are denoted by Ef1 and Ef2, respectively, and the detection value of the drive amount of a driven body is denoted by Ef. A gain calculator 27 calculates the gains G1 and G2 on the basis of Ef1, Ef and Ef2. An upper limit value of Ef, which denotes the drive amount of the driven body, is denoted by Lmax. When Ef1, Ef2 or Ef approaches zero, the first gain G1 is brought close to (Ef1?Lmax/2)/(Ef?Lmax).

Abstract: A 0-axis current calculator 7 configured to calculate a target value of the 0-axis current by setting the current of the open phase to be zero when one of the phases becomes open, or determines that the target value of the 0-axis current is zero when there is no open phase is provided. Based on the target values of the d-axis current and the q-axis current, the target value of the 0-axis current calculated by the 0-axis current calculator 7, and the d-axis current, the q-axis current, and the 0-axis current transformed by the d-q-0 transformer 8, the current supplied to each phase of the motor are controlled.

Abstract: A 0-axis current calculator 7 configured to calculate a target value of the 0-axis current by setting the current of the open phase to be zero when one of the phases becomes open, or determines that the target value of the 0-axis current is zero when there is no open phase is provided. Based on the target values of the d-axis current and the q-axis current, the target value of the 0-axis current calculated by the 0-axis current calculator 7, and the d-axis current, the q-axis current, and the 0-axis current transformed by the d-q-0 transformer 8, the current supplied to each phase of the motor are controlled.

Abstract: Multipliers 21a and 21b output values, which are obtained by multiplying a total drive command value Es by first and second gains G1 and G2, respectively, as first and second drive command values E1 and E2. Controllers 23a and 23b control first and second actuators (motors) 5 and 7, respectively, on the basis of the first and second drive command values. The detection values of the drive amounts of the actuators are denoted by Ef1 and Ef2, respectively, and the detection value of the drive amount of a driven body is denoted by Ef. A gain calculator 27 calculates the gains G1 and G2 on the basis of Ef1, Ef and Ef2. An upper limit value of Ef, which denotes the drive amount of the driven body, is denoted by Lmax. When Ef1, Ef2 or Ef approaches zero, the first gain G1 is brought close to (Ef1?Lmax/2)/(Ef?Lmax).

Abstract: The PWM signal generator of the present invention generates a first pulse waveform in which a first on-time ?T1 calculated by a first on-time calculator (401) is used as an on-duration, and a second pulse waveform in which a second on-time ?T2, calculated by a second on-time calculator (402) when a preset delay time has elapsed from the start of the calculation of the first on-time ?T1, is used as an on-duration. Also, a PWM signal generator (413) generates a PWM signal on the basis of a composite pulse in which the generated first pulse waveform and second pulse waveform are combined, and the first on-time calculator (401) calculates the first on-time ?T1 at the end of the composite pulse waveform.

Abstract: An arc detecting device includes a detector for acquiring time series data concerning a characteristic quantity, such as a voltage or a current in a circuit, targeted for detecting an arc; a basic data generator for generating basic data made of a plurality of frequency components, through frequency analysis from the acquired time series data; a data processor for statistically processing the generated basic data, thereby converting the basic data to an evaluation value highly correlative to an occurrence of the arc; and an arc judging unit for judging the occurrence of the arc, if the evaluation value exceeds a predetermined arc judgment threshold value. In this manner, the arc detecting device that is capable of effectively detecting the arc in a direct-current power supply circuit is provided.

Abstract: In CDMA communications, a base station detects a difference between a reference phase of a spreading code and a phase of a received signal of each terminal station, and feeds a phase jump signal PJ-i representative of the phase difference back to each terminal station. After timing acquisition, the reception operation is performed using the reference phase, and a shift amount between the phase of a received signal and the reference phase is fed back to each terminal station as phase synchronization control information PC-i. Each terminal station coarsely adjusts the phase of the spreading code in accordance with the phase jump signal PJ-i, and thereafter finely adjusts the phase of its transmitting signal in accordance with the phase synchronization control information PC-i. It is therefore possible to synchronize the phases of the signals transmitted from terminal stations and received at the base station. Accordingly, an orthogonal code is used for spreading on the reverse links.

Abstract: The PWM signal generator of the present invention generates a first pulse waveform in which a first on-time ?T1 calculated by a first on-time calculator (401) is used as an on-duration, and a second pulse waveform in which a second on-time ?T2, calculated by a second on-time calculator (402) when a preset delay time has elapsed from the start of the calculation of the first on-time ?T1, is used as an on-duration. Also, a PWM signal generator (413) generates a PWM signal on the basis of a composite pulse in which the generated first pulse waveform and second pulse waveform are combined, and the first on-time calculator (401) calculates the first on-time ?T1 at the end of the composite pulse waveform.

Abstract: An arc detecting device includes: a detector for acquiring time series data concerning a characteristic quantity, such as a voltage or a current in a circuit, targeted for detecting an arc; a basic data generator for generating basic data made of a plurality of frequency components, through frequency analysis from the acquired time series data; a data processor for statistically processing the generated basic data, thereby converting the basic data to an evaluation value highly correlative to an occurrence of the arc; and an arc judging unit for judging the occurrence of the arc, if the evaluation value exceeds a predetermined arc judgment threshold value. In this manner, the arc detecting device that is capable of effectively detecting the arc in a direct-current power supply circuit is provided.

Abstract: In CDMA communications, a base station detects a difference between a reference phase of a spreading code and a phase of a received signal of each terminal station, and feeds a phase jump signal PJ-i representative of the phase difference back to each terminal station. After timing acquisition, the reception operation is performed using the reference phase, and a shift amount between the phase of a received signal and the reference phase is fed back to each terminal station as phase synchronization control information PC-i. Each terminal station coarsely adjusts the phase of the spreading code in accordance with the phase jump signal PJ-i, and thereafter finely adjusts the phase of its transmitting signal in accordance with the phase synchronization control information PC-i. It is therefore possible to synchronize the phases of the signals transmitted from terminal stations and received at the base station. Accordingly, an orthogonal code is used for spreading on the reverse links.

Abstract: In CDMA communications, a base station detects a difference between a reference phase of a spreading code and a phase of a received signal of each terminal station, and feeds a phase jump signal PJ-i representative of the phase difference back to each terminal station. After timing acquisition, the reception operation is performed using the reference phase, and a shift amount between the phase of a received signal and the reference phase is fed back to each terminal station as phase synchronization control information PC-i. Each terminal station coarsely adjusts the phase of the spreading code in accordance with the phase jump signal PJ-i, and thereafter finely adjusts the phase of its transmitting signal in accordance with the phase synchronization control information PC-i. It is therefore possible to synchronize the phases of the signals transmitted from terminal stations and received at the base station. Accordingly, an orthogonal code is used for spreading on the reverse links.

Abstract: In CDMA communications, a base station detects a difference between a reference phase of a spreading code and a phase of a received signal of each terminal station, and feeds a phase jump signal PJ-i representative of the phase difference back to each terminal station. After timing acquisition, the reception operation is performed using the reference phase, and a shift amount between the phase of a received signal and the reference phase is fed back to each terminal station as phase synchronization control information PC-i. Each terminal station coarsely adjusts the phase of the spreading code in accordance with the phase jump signal PJ-i, and thereafter finely adjust the phase of its transmitting signal in accordance with the phase synchronization control information PC-i. It is therefore possible to synchronize the phases of signals transmitted from terminal stations and received at the base station. Accordingly, an orthogonal code is used for spreading on reverse links.

Abstract: In CDMA communications, a base station detects a difference between a reference phase of a spreading code and a phase of a received signal of each terminal station, and feeds a phase jump signal PJ-i representative of the phase difference back to each terminal station. After timing acquisition, the reception operation is performed using the reference phase, and a shift amount between the phase of a received signal and the reference phase is fed back to each terminal station as phase synchronization control information PC-i. Each terminal station coarsely adjusts the phase of the spreading code in accordance with the phase jump signal PJ-i, and thereafter finely adjusts the phase of its transmitting signal in accordance with the phase synchronization control information PC-i. It is therefore possible to synchronize the phases of the signals transmitted from terminal stations and received at the base station. Accordingly, an orthogonal code is used for spreading on the reverse links.

Abstract: In CDMA communications, a base station detects a difference between a reference phase of a spreading code and a phase of a received signal of each terminal station, and feeds a phase jump signal PJ-i representative of the phase difference back to each terminal station. After timing acquisition, the reception operation is performed using the reference phase, and a shift amount between the phase of a received signal and the reference phase is fed back to each terminal station as phase synchronization control information PC-i. Each terminal station coarsely adjusts the phase of the spreading code in accordance with the phase jump signal PJ-i, and thereafter finely adjusts the phase of its transmitting signal in accordance with the phase synchronization control information PC-i. It is therefore possible to synchronize the phases of the signals transmitted from terminal stations and received at the base station. Accordingly, an orthogonal code is used for spreading on the reverse links.

Abstract: In CDMA communications, a base station detects a difference between a reference phase of a spreading code and a phase of a received signal of each terminal station, and feeds a phase jump signal PJ-i representative of the phase difference back to each terminal station. After timing acquisition, the reception operation is performed using the reference phase, and a shift amount between the phase of a received signal and the reference phase is fed back to each terminal station as phase synchronization control information PC-i. Each terminal station coarsely adjusts the phase of the spreading code in accordance with the phase jump signal PJ-i, and thereafter finely adjusts the phase of its transmitting signal in accordance with the phase synchronization control information PC-i. It is therefore possible to synchronize the phases of the signals transmitted from terminal stations and received at the base station. Accordingly, an orthogonal code is used for spreading on the reverse links.

Abstract: A communication system having a central station and a plurality of terminal stations coupled through a bi-directional communication path such that the terminals communicate with each other through the central station, has dedicated communication channels assigned to couple a terminal station with another terminal station and common communication channels simultaneously assigned to the plurality of terminal stations in a multiplexing manner. The central station has a control unit for selecting one from the dedicated communication channels and the common communication channels in response to a communication request from a terminal station.