摘要:
A multi-phase voltage converting device includes voltage converters each performing voltage conversion based on a control period selected from among a plurality of predetermined control periods, and a control device indicating the control period to the voltage converters. The control device updates the control period of voltage converters in a predetermined period related commonly to the plurality of control periods. The update period is a least common multiple of the plurality of control periods. The plurality of voltage converters are n in number, and the control device successively updates the control periods for the plurality of voltage converters with a time difference equal to 1/n of the update period. Thereby, the multi-phase voltage converting device suppressing output voltage ripples can be provided.
摘要:
A voltage boost converter includes: a main voltage boost portion that has a first switch and a first coil, and that raises output voltage of a direct-current power source by using counter electromotive force of the coil caused by the switch performing a switching action on the coil; and a subsidiary voltage boost portion which has a capacitor that adjusts potential difference between two poles of the switch by amount of electricity stored, and which reduces switching loss of the switch by adjusting the amount of electricity in the capacitor during the switching action, and which has a second switch and a second coil. The second coil is formed by winding a wire around at least a portion of a core formed of a magnetic body. The core is provided with a gap formed of a non-magnetic body. A core region formed of a magnetic body is adjacent to the gap.
摘要:
A voltage conversion circuit apparatus that adjusts a timing skew between the switching control of the first switching element and the switching control of the second switching element includes: a skew storage portion that stores a timing skew between the switching controls of the first and second switching elements after the voltage conversion circuit apparatus is manufactured; and a timing adjustment portion that corrects the stored timing skew and thereby adjusts the timing relation between a first pulse signal and a second pulse signal so as to bring within a permissible range the timing skew that occurs when the switching controls of the first and second switching elements are performed by using the first pulse signal and the second pulse signal.
摘要:
A fuel cell system is configured to have: a voltage superimposing unit that superimposes a predetermined AC signal on an output voltage of a fuel cell; a unit that detects an output voltage value of a battery device, the output voltage value varying as the fuel cell output voltage value on which the AC signal has been superimposed varies; a battery device voltage comparison unit that compares the detected battery device output voltage value with a predetermined threshold voltage; and a measurement permission determination unit that determines whether the AC impedance measurement is permitted or not based on whether or not the battery device output voltage value exceeds the threshold voltage. The fuel cell system can protect the battery device in the impedance measurement of the fuel cell based on an AC impedance method.
摘要:
When the operation point of a DC/DC converter, which steps up/down the output voltage of a fuel cell stack, is in a range of reduction in response capability and further there is issued a request of determining an AC impedance, a controller switches numbers of the drive phases of the DC/DC converter to determine an AC impedance of the fuel cell stack. If the operation point of the DC/DC converter is in the range of reduction in response capability and further the precision of determining the AC impedance is reduced, then the determination of AC impedance in the range of reduction in response capability is inhibited and the switching of the phases of the DC/DC converter is implemented, thereby causing the operation point of the DC/DC converter to be out of the range of reduction in response capability, with the result that the precision of determining the AC impedance can be raised.
摘要:
A converter device which is configured by connecting three converter circuits in parallel is provided between a secondary battery serving as a first power supply and a fuel cell serving as a second power supply. A control unit includes a PID control module which controls the converter device by PID control, for executing desired voltage conversion; a module for modifying the number of drive phases which changes the number of drive phases of the converter device in response to an electric power passing through the converter device; and a gain switching module which switches feedback gains in the PID control when the number of drive phases is changed.
摘要:
A converter device which is configured by connecting three converter circuits in parallel is provided between a secondary battery serving as a first power supply and a fuel cell serving as a second power supply. A control unit includes a PID control module which controls the converter device by PID control, for executing desired voltage conversion; a module for modifying the number of drive phases which changes the number of drive phases of the converter device in response to an electric power passing through the converter device; and a gain switching module which switches feedback gains in the PID control when the number of drive phases is changed.
摘要:
A fuel cell system capable of improving the voltage controllability of a converter provided in the system is provided. A controller judges whether or not a passing power of a DC/DC converter falls within a reduced response performance area for the number of active phases as of the present moment. When the controller determines that the passing power of the DC/DC converter falls within the reduced response performance area, the controller determines the number of phases which avoids the driving within the reduced response performance area, and outputs a command for switching to the determined number of phases (phase switching command) to the DC/DC converter.
摘要:
A driving frequency setting portion is provided. The driving frequency setting portion sets a switching frequency of a switching element on the basis of a notification from a driving phase number switching portion. A ripple current detected by a current sensor is in inverse proportion to inductance of reactor. Since a ripple current becomes the largest in the single-phase driving, in this embodiment, considering both the ripple current and switching loss, a switching frequency for the single-phase driving is set higher than a switching frequency for multiphase driving.
摘要:
Provided is a converter control device which detects an on-failure of an auxiliary switch constituting an auxiliary circuit of a soft switching converter and can prevent element failures. A current sensor for detecting the current flowing in a coil is provided between a fuel cell and the. A controller sequentially detects current by use of the current sensor and makes a judgment as to whether or not the detected current has exceeded an overcurrent threshold value stored in a memory (not shown). When the controller judges that the current has exceeded the overcurrent threshold value, the controller judges that a second switching element has an on-failure, and performs a fail-safe operation by stopping the driving of a converter (for example, a U-phase converter) of an auxiliary circuit provided with this second switching element.