摘要:
An electric load apparatus (100) includes a DC power source (B), a voltage sensor (10, 20), system relays (SR1, SR2), a capacitor (11, 13), a DC/DC converter (12), an inverter (14), a current sensor (24), a rotation sensor (25), a control apparatus (30), and an AC motor (M1). The control apparatus (30) restricts an increase amount of consumed power in the AC motor (M1) in a range in which the driving operation of the electric load apparatus (100) can be maintained, when the increase amount of the consumed power in the AC motor (M1) exceeds an allowable power that can be supplied from the capacitor (13) to the inverter (14).
摘要:
On end of a reactor (L1) is connected to a positive electrode of a battery (B1) and the other end is connected to a power line via a transistor (Q1) and to the ground via a transistor (Q2). By PWM control of the transistors (Q1, Q2), an arbitrary increased voltage is obtained in the power line. It is possible to obtain an optimal inverter input voltage (power line voltage) according to the motor drive state, thereby increasing efficiency. Thus, it is possible to optimize the inverter input voltage according to the motor drive condition.
摘要:
An electronic control unit (40) calculates the current flowing through a reactor (L) by dividing an output required BP* of a battery (32), obtained from converting the power required by a motor (22), by a terminal voltage Vb of the battery (32). A carrier frequency (optimum carrier frequency) is set for transistors (T7, T8) where the loss of a DC/DC converter (34) is minimized from the calculated current, and the DC/DC converter (34) is controlled at the set switching frequency.
摘要:
A power plant outputs motive power by driving a motor (22) using electric power from a direct-current power source (32). When the direct-current power source (32) has a low temperature, the direct-current power source is rapidly heated, whereby the performance can fully be demonstrated. In the power plant in which a capacitor (30) is installed so as to connect a positive electrode bus (26) and a negative electrode bus (28) of an inverter circuit (24) and the direct-current power source (32) is also installed so as to connect the negative electrode bus (28) of the inverter circuit (24) and a neutral point of the motor (22), when a power source temperature (Tb) of the direct-current power source (32) detected by a temperature sensor (50) is less than or equal to a threshold temperature (Tblow) at which supply of required electric power to the motor (22) is possible, an electronic control unit (40) sets a voltage between terminals of the capacitor (30) higher than normal and also sets a frequency of a carrier wave lower than normal, and performs switching control of transistors (T1 to T6) Thus, a ripple of a neutral point current which flows into the direct-current power source (32) can be increased, whereby it is possible to promote calorification of the direct current power source (32).
摘要:
When the absolute values of the negative voltage V− and the positive voltage V+ of a rectangular wave to be applied to the three phase coils of the motor driven using a rectangular-waved voltage are different, time T1 and time T2 for the rectangular wave are adjusted such that the area A representing the absolute value of a time integration value of the negative voltage V− and the area B representing the absolute value of a time integration value of the positive voltage V+ becomes equal to each other. With this adjustment, the average voltage of the rectangular wave becomes of value 0, so that a DC component current is prevented from flowing into the three phase coils of the motor.
摘要:
A direct-current power supply (40) is connected between the neutral points of two three-phase coils (24, 26) of a 2Y motor (22) constituted of the windings of the two three-phase coils (24, 26), which are connected in Y-connection and wound on a same stator, and to which three-phase alternating current power is severally supplied with a phase difference of a shifted angle between the windings from two inverter circuits (30, 32) having a positive pole bus (34) and a negative pole bus (36) for common use. A capacitor (38) is connected between the positive pole bus (34) and the negative pole bus (36). The electric potential difference between the neutral points of the three-phase coils (24, 26) is made larger or smaller than the voltage of the direct-current power supply (40) through the switching control of the inverter circuits (30, 32). Thereby, the capacitor (38) can be charged or discharged. Consequently, an inverter input voltage can be adjusted within a wide range.
摘要:
A direct-current power supply connecting the negative pole bus of an inverter circuit and the neutral point of a motor and a capacitor connecting the positive pole bus of the inverter circuit and the neutral point of the motor are provided for performing the switching control of the transistors T1-T6 of the inverter circuit on the basis of a phase voltage command value formed by the addition of a direct-current component and an alternating-current component. The voltage between the terminals of the capacitor is controlled on the direct-current component, and the driving control of the motor is performed on the alternating-current component. The supply voltage of the direct-current power supply can be made to be lower than a voltage necessary to drive the motor. Moreover, the withstand voltage of the capacitor can be made to be smaller and the relay circuit can be simplified in comparison with an apparatus equipped with a capacitor connected between the positive pole bus and the negative pole bus of an inverter circuit. As a result, the downsizing of an apparatus and the reduction in costs can be achieved, and the durability and the reliability of the apparatus can be improved.
摘要:
To improve accuracy in controlling battery output, a charge-storage element is connected in parallel to a plurality of power source units. Each power source unit includes a power source element, and power transmission and reception between the power source element and a neutral point N side can be controlled by controlling the ratio of time over which an open/close switch remains closed, determined according to which among the voltage at the power source element or a voltage across the power source unit is larger or smaller. As an output of each power source element can be controlled, accuracy in output control for the combination battery can be improved.
摘要:
In regenerative braking mode, an inverter converts, according to PWMC signal from a control unit, an AC voltage generated by a motor into a DC voltage to supply the converted DC voltage to an up-converter which down-converts the DC voltage to charge a DC power supply. The control unit receives voltage V2 from a voltage sensor to stop the up-converter if voltage V2 is higher than a predetermined value. The control unit further receives voltage Vf from a voltage sensor that is applied to a DC/DC converter and stops the up-converter if voltage Vf is higher than a predetermined value. Moreover, the control unit receives voltage V1 of the DC power supply from a voltage sensor to stop the up-converter if voltage V1 does not match voltage V2.
摘要:
In regenerative braking mode, an inverter converts, according to PWMC signal from a control unit, an AC voltage generated by a motor into a DC voltage to supply the converted DC voltage to an up-converter which down-converts the DC voltage to charge a DC power supply. The control unit receives voltage V2 from a voltage sensor to stop the up-converter if voltage V2 is higher than a predetermined value. The control unit further receives voltage Vf from a voltage sensor that is applied to a DC/DC converter and stops the up-converter if voltage Vf is higher than a predetermined value. Moreover, the control unit receives voltage V1 of the DC power supply from a voltage sensor to stop the up-converter if voltage V1 does not match voltage V2.