Ryuya Yoshida

A novel A-D conversion for digital control switching power supply

This paper proposes a novel A-D conversion method for the digital P-I-D control in order to improve the transient response in the switching power supply. The P-I-D control circuit has a delay time mainly due to the calculation and sampling. This delay heavily affects the transient responses. In the presented method, the P-I-D is divided into two parts, the P control and the I-D control, independently. In the P control, the high speed and low resolution A-D converter is used to realize the quick control for the transient response. In the I-D control, the high resolution and low speed A-D converter is used to realize the accurate regulation characteristics. The cost of proposed method which is used two A-D converter is lower than the high resolution and high speed A-D converter. As result, it is confirmed that the proposed method have equivalent transient response to the high-cost one. This suggests that the proposed method is the efficient approach to realize the high performance design of the control circuit in low cost.

Digital Fast P Slow ID Control DC–DC Converter Using A–D Converters in Different Resolutions

The purpose of this paper is to present a digital fast P and slow ID control dc-dc converter using A-D converters in different resolutions. In the proposed method, the operation parts are divided into the P control and the ID control. Moreover, the high-speed and low resolution A-D converter is set for the P control, and the very low-speed and high resolution one is set for the ID control. In the transient response experiment, the convergence time is improved by about 77% compared with the conventional PID control method. As a result, it is possible to achieve the low cost design with keeping the superior transient response.

A new improved fast digital PID control DC-DC converter using a complementing low-resolution fast A-D converter

In the previous research, the fast P control method is proposed. In this method, the PID control part is divided into the P control and I-D control parts. The high speed-low resolution A-D converter and low speed-high resolution A-D converter are required for the P control and I-D control, respectively. These two A-D converters are lower cost than the high-speed and high-resolution A-D converter. Therefore, in this method, it is possible to reduce the cost. However, the minimum number of bits of A-D converter for the P control is not discussed yet. It is necessary to discuss the number of bits of A-D converter for the P control. This paper presents a new fast digital PID control dc-dc converter using a complementing low-resolution fast A-D converter. The minimum number of bits of A-D converter is discussed in both the existing fast P and proposed methods. As a result, the number of bits of A-D converter for P control reduces 3 bits compared to the existing fast P method.

Transient response of novel P-I-D digital control switching power supply for HVDC system

This paper presents a novel 800W proto type digital P-I-D control switching power supply for the high voltage direct-current(HVDC) power feeding system The digital control circuit for HVDC power feeding system has some problems. Especially, the conversion time of A-D converter and the processing time of digital controller exert a bad influence upon the dynamic characteristics. In the proposed method, the calculation processes of P and I-D controls are parallel. The delay time of P control is less than that of I-D control. The results against the step change of load are discussed. As a result, it is revealed that the proposed circuit has the superior transient response.

Digital fast-P slow-ID control DC-DC converter

This paper presents a new digital control method for dc-dc converter which consists of two A-D converters with different sampling frequencies. In the presented method, the calculation process of P and ID controls are parallel. The sampling frequency for the P control is higher than the switching frequency and one for ID control is lower than the switching frequency. Therefore, the P control and ID control have different sampling frequency each other. Even in such different setting compared with the conventional PID control method, our presented method can realize the superior transient response. The presented method also contributes the low-cost design of A-D converters. In the experiments, it is obtained that the undershoot of the output voltage and the convergence time are improved by 44% and 78% respectively in the transient response. From the results, it is confirmed that our presented method can provide superior transient characteristics and the low cost implementation simultaneously.

Digital fast-P slow-ID control DC-DC converter using A-D converters in different resolutions

The purpose of this paper is to present a digital fast-P and slow-ID control dc-dc converter using A-D converters in different resolutions. In the proposed method, the operation parts are divided into the P control and the ID control. Moreover, the high-speed and low resolution A-D converter is set for the P control, and the very low-speed and high resolution one is set for the ID control. In the transient response experiment, the convergence time is improved by about 77% compared with the conventional PID control method. As a result, it is possible to achieve the low cost design with keeping the superior transient response.

A new quick response digital control switching power supply unit for HVDC system

The purpose of this paper is to present a new digital control switching power supply for the HVDC system in data center. The two stage converters are proposed to address the problem of input voltage drop. It consists of the boost converter and the phase-shifted full bridge converter. Since the first stage boost converter make the output voltage constant, good regulation characteristics against the input voltage of the server as the load and superior transient response are achieved with keeping high efficiency in this proposed converter for HVDC. A digital peak current mode control and the existing fast P control are implemented. And then the transient responses of converters in parallel operation are discussed because it is needed in the data center. The digital control method presented in this paper achieves the superior response compared with the existing digital control. It is experimentally verified with 800W prototypes that this unit has superior static and dynamic characteristics.

Transient response of novel fast digital PID control DC-DC converter

This paper proposes a new fast response digital PID control circuit for dc-dc converter and its transient response. In the conventional digital PID control method, the switching frequency of dc-dc converter and the sampling frequency of A-D converter is the same and the calculation process of the PID control is series of operation. On the other hand, in the proposed method, the PID control is divided into two parts, the PD control and the I control, independently. The sampling frequency of the I control is same to the conventional method. However, the sampling frequency of the PD control is higher than that of the I control. The results against the step change of load are discussed. As a result, it is revealed that the proposed circuit has the superior transient response.

Transient response of fast digital PID control switching power supply

The purpose of this paper is to present the transient response in the proposed digitally controlled dc-dc converter under the various changes. The digital PID control circuit has a delay time mainly due to the calculation and sampling. This delay time heavily affects the transient responses. In the proposed method, a twist is added to the PID control in order to achieve fast response. In addition, two kinds of low-cost A-D converters are used to realize low-cost design of the digital control circuit. As a result, the convergence time of proposed method is improved about 75% as compared with conventional method. Similarly, the undershoot of output voltage is improved about 45%. It is confirmed that the proposed method have superior transient response under the various changes.

A fast response digitally controlled full bridge converter

This paper presents a fast response digitally controlled full bridge converter in parallel operation. The digital controlled circuit has some problem. One of the main problems is the delay time. The delay time includes the conversion time of A-D converter and processing time of digital controller. It exerts a bad influence on the dynamic characteristic. In the proposed method, the sample timing for P control is contrived, thus the delay time for P control is minimized. The proposed fast P control method is applied to the full bridge converters in parallel operation. It is confirmed that the proposed method has superior transient response compared to the conventional method. The proposed digitally controlled parallel full bridge converter is suitable to the power converter for automotive.