TAILIEUCHUNG - Advances in PID Control Part 11

Tham khảo tài liệu 'advances in pid control part 11', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 190 Advances in PID Control Furthermore the arbitrary frequency characteristics can be created by introducing a new frequency characteristic. Here the design method and system stability of the proposed control technique is examined by using buck converter as a simple example. 2. Converter analysis For the design of the control system it is necessary to grasp correctly the characteristics of the converter in detail. The buck converter as a controlled object is shown in Fig. 1. The dynamic characteristics of buck converter can be derived by applying the state space averaging method 8 9 . The transfer function of duty to output voltage of buck converter is derived following equation Gdv s - AVp s AD s Gdvo s P s 1 where P s s s 2f 1 2 - 3 R rL - LC R rc 4 Fig. 1. Synchronous buck converter. s_ L C Rrc rL R rc 2ạ LC R r R rL 5 1 cc esr 6 Figure 2 shows the block diagram of analog system. From Fig. 2 the loop gain of analog controlled converter can be derived following equation Pole-Zero-Cancellation Technique for DC-DC Converter 191 T s AV s Gdv s G s K K PWM AVO s P s s 7 where Gc s Transfer function of phase compensator K DC gain of error amp. Ks Sense gain of output voltage PWM transfer gain of voltage to duty In order to evaluate the validity of the analytical result the experimental circuit is implemented by means of the specifications and parameters shown in Table 1. Symbol Description Value Vi Input Voltage 12V Vo Io Load Condition 5A L Filter Inductor 22pH C Filter Capacitor 470pF rL DC Resistance of L 100mQ rc ESR of C 10mQ R Load Resistance 1Q Ks Sense Gain K Feedback DC Gain 5 PWM PWM Gain fs Switching Frequency 100kHz Table 1. Circuit parameters and specifications. Figure 3 shows the loop gain of the buck converter with p-control in analog control. As shown in Fig. 3 the analytical and experimental results are agreed well. However as shown in Fig. 4 the big difference is shown in phase characteristics at high frequency side between analog .

TỪ KHÓA LIÊN QUAN
TÀI LIỆU MỚI ĐĂNG
Đã phát hiện trình chặn quảng cáo AdBlock
Trang web này phụ thuộc vào doanh thu từ số lần hiển thị quảng cáo để tồn tại. Vui lòng tắt trình chặn quảng cáo của bạn hoặc tạm dừng tính năng chặn quảng cáo cho trang web này.