A Wireless Power Transfer Charger with Hybrid Compensation Topology for Constant Current/Voltage Onboard Charging
Round 1
Reviewer 1 Report
In paper “A Wireless-Power-Transfer Charger with Hybrid 2 Compensation Topology for Constant Current/Voltage 3 Onboard Charging” proposed a wireless charging device with implemented CC and CV and high design freedom of the transfer gain modes DS-LCC compensation topology.
Remarks
- In the paper overview is mentioned about three categories of WPT schemes. Below, only two categories are presented. Where is the third one?
- According Fig. 5 (a) and (b), it seems that there is ZPA point not only for f = 85 kHz but also for f = 110 kHz. It should be briefly discussed why ZPA point for f = 85 kHz is better.
- "Figure 5. (a) Input phase angle of the input equivalent impedance; (b) transconductance gain of the DS-LCC topology." In Fig. 5 all is vice versa. You should swap (a) and (b) in the caption to the figure. The same situation is with Fig. 9.
- It is unclear how formula (11) is obtained from (10) if the imaginary part of (10) is
jω(Lp-L1-1/(ω^2*CF1))RAC = 0 -> L1 = Lp - 1/(ω^2*CF1).
- “As shown in Figure 9(b), when the operating frequency is less than the resonant frequency, QIN is positive, indicating that the system presents inductive.” According to Fig. 9(b) this statement is wrong for Rbat = 7Ω.
- “… can implement a CV charging mode regardless of the variation of battery equivalent resistance.” The statement “regardless of the variation of battery equivalent resistance” is unsubstantiated.
- Fig. 12 is very uninformative.
- if kV = Vref/Vb, comparator positive pin signal C+ is always equal C+ = Vb*kV= Vref. Hence C+ = C- = Vref. Therefore, circuit does not work properly.It would be better if kV = Vref/Vbmax, where Vbmax is boundary voltage from CC to CV mode.
- if kV = Vref/Vbmax , according Fig. 12(b) we can define
Vb < Vbmax (CC mode) -> S1 = 0, S2 = 1,
Vb = Vbmax (CV mode), S1=1, S2=0,
but in Fig. 12 (a) all is vice versa. So, the comparator input signals (Vb and Vref) should be swapped;
- also for clarity of Fig. 12(a) it would be better to use battery voltage Vb on axes “x” instead time.
- Formulas (15) is unclear:
- in the paper is mentioned “the WPT charging systems, the input voltage can be 306 modulated by the FBI into a square wave voltage with a 0.5-T duty cycle”. So, voltage Uin is directly after FBI and before compensation circuit, duty cycle = 0.5 and Uin is a square wave, therefore Uin = Udc;
- for Idc = Iin*2*2^0.5/pi it is necessary to connect capacitor Cin directly after Udc as dc filter, Fig. 6. For proposed topology Idc = Iin, because Iin is inverted current of Idc, therefore their RMS values are equal.
You should show how formulas (15)-(18) are derived.
- For 100 V charger C3M0030090K transistors with drain to source voltage 900 V are used. This looks out of place.
- In the paper some parameters have different notifications:
- input phase angle is defined both symbols QIN and θIN;
- output voltage – Uo and Vo;
- battery voltage – Ub and Ubat.
- In the paper https://www.mdpi.com/2073-8994/12/9/1453/pdf
also hybrid compensation topology is proposed. What benefits has your solution compared to this one?
Author Response
Thank you for reviewer's comments. All responses are included in the attached file. Please see the attachment.
Author Response File: 
Author Response.docx
Reviewer 2 Report
The paper proposes a 12 constant current/voltage (CC/CV) charging compensation topology with near-communication 13 based on receiving-side hybrid-topology switching, which is unaffected by the dynamic loads. The paper is interesting; however, I have some comments:
Please, indicate when references are needed, regarding implemented equations.
Please, enhance the quality of Figure 14. It is hard to observe the figure and read the captions.
Rest of paper is correct.
Author Response
Thank you for reviewer's comments. All responses are included in the attached file. Please see the attachment.
Author Response File: Author Response.docx
