DC / DC boost converter based on charge pump, chip and energy storage equipment

Abstract

The embodiment of the invention provides a DC / DC boost converter based on a charge pump, a chip and energy storage equipment. The DC / DC boost converter based on the charge pump comprises a switch controller, a pre-stage main circuit and a post-stage charge pump circuit, wherein the pre-stage main circuit and the post-stage charge pump circuit are connected in parallel in an interleaving manner; the pre-stage main circuit comprises a rechargeable battery, a first inductor, a second inductor, a first switch and a second switch; wherein the source electrode of the first switch is connected with the post-stage charge pump circuit; the source electrode of the second switch is connected with the post-stage charge pump circuit; the post-stage charge pump circuit comprises a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, a first diode, a second diode, a third diode, an output diode, a load capacitor and a load resistor; the switch controller is connected with the source electrode of the first switch and the source electrode of the second switch in the front-stage main circuit so as to provide switch control signals for the first switch and the second switch, control the switching states of the first switch and the second switch and control the output voltage in the rear-stage charge pump circuit, and therefore high-gain boosting is achieved based on the small duty ratio.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of energy storage devices, and specifically to a DC / DC boost converter, chip and energy storage device based on a charge pump. Background Art

[0002] The grid-connected household photovoltaic energy storage system can save transmission and distribution costs, achieve lower costs, improve power quality and energy efficiency, and solar energy has excellent environmental protection characteristics, renewable energy characteristics and sustainable development characteristics. In a specific example, solar photovoltaics can be used to charge batteries. At this time, the battery voltage needs to pass through a DC / DCboost (DC-DC boost) converter to boost it to a high-voltage bus voltage of about 400V, and finally converted to 220V AC through an inverter.

[0003] However, the battery voltage is generally around 20V-40V. If a conventional non-isolated boost converter is used to increase the voltage to 400V, the circuit switch tube of the Boost converter needs to have a higher duty cycle, that is, the voltage stress on the circuit switch tube of the Boost converter is directly output as the output voltage, which requires the Boost converter to have a higher device stress and its output efficiency (that is, the ratio of output power to input power) is significantly reduced.

[0004] It can be seen that providing what kind of DC / DC converter to achieve high-gain boost based on a smaller duty cycle has become a technical problem that technical personnel in this field need to solve urgently. Summary of the invention

[0005] In view of this, embodiments of the present application provide a DC / DC boost converter, chip, and energy storage device based on a charge pump to achieve high-gain boost based on a smaller duty cycle.

[0006] To solve the above problems, an embodiment of the present application provides a DC / DC boost converter based on a charge pump, comprising: a switch controller and a front-stage main circuit and a rear-stage charge pump circuit connected in parallel;

[0007] The front-stage main circuit includes a rechargeable battery, a first inductor, a second inductor, a first switch and a second switch; wherein the rechargeable battery is used to provide a battery voltage, the positive electrode of the rechargeable battery is connected to the first node of the positive electrode of the first inductor and the second inductor connected in parallel on the branch; the negative electrode of the rechargeable battery is connected to the second node of the gate electrode of the first switch and the second switch connected in parallel on the branch; the negative electrode of the first inductor is connected to the source electrode of the first switch; the source electrode of the first switch is connected to the rear-stage charge pump circuit; the negative electrode of the second inductor is connected to the source electrode of the second switch; the source electrode of the second switch is connected to the rear-stage charge pump circuit;

[0008] The post-stage charge pump circuit includes a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, a first diode, a second diode, a third diode, an output diode, a load capacitor and a load resistor; wherein the first capacitor and the third capacitor are connected in parallel, and the second capacitor and the fourth capacitor are connected in parallel; the first diode, the second diode, the third diode and the output diode are connected in series; and the positive electrode of the first diode is connected to the negative electrode of the first capacitor, the positive electrode of the second diode is connected to the negative electrode of the second capacitor, the positive electrode of the third diode is connected to the negative electrode of the third capacitor, and the positive electrode of the output diode is connected to the negative electrode of the fourth capacitor; the negative electrode of the load capacitor is connected to the positive electrode of the load resistor, and the negative electrode of the load resistor is connected to the positive electrode of the first diode; the positive electrode of the load capacitor is connected to the negative electrode of the output diode; and the negative electrode of the load capacitor is grounded;

[0009] The switch controller is connected to the source of the first switch and the source of the second switch in the front-stage main circuit to provide a switch control signal to the first switch and the second switch to control the switch state of the first switch and the second switch to control the output voltage in the rear-stage charge pump circuit.

[0010] Optionally, the source of the first switch is connected to the subsequent charge pump circuit specifically: the source of the first switch is connected to a seventh node on a parallel connection branch of a second capacitor and a fourth capacitor in the subsequent charge pump circuit;

[0011] The source of the second switch is connected to the subsequent charge pump circuit specifically: the source of the second switch is connected to the eighth node on the parallel connection branch of the first capacitor and the third capacitor in the subsequent charge pump circuit.

[0012] Optionally, the switch control signal provided by the switch controller to the first switch is a first switch control signal, and the second switch control signal provided to the second switch is a second switch control signal;

[0013] The first switch control signal and the second switch control signal have the same time period and duty cycle, and the waveforms of the first switch control signal and the second switch control signal are associated with each other.

[0014] Optionally, the waveforms of the first switch control signal and the second switch control signal are associated with each other in the following manner: a phase difference between a waveform phase of the first switch control signal and a waveform phase of the second switch control signal is 180°.

[0015] Optionally, corresponding to the first switch control signal and the second switch control signal,

[0016] If the first switch and the second switch are turned on, the rechargeable battery in the front-stage main circuit forms a loop with the first inductor and the second inductor respectively, and the output voltage of the load resistor in the rear-stage charge pump circuit corresponds to the load capacitance;

[0017] If the first switch is turned off and the second switch is turned on, the rechargeable battery in the front-stage main circuit forms a loop with the first inductor, the first diode and the third diode in the rear-stage charge pump circuit are turned off, and the second diode and the output diode are turned on; and the current flowing through the first inductor in the front-stage main circuit is used to discharge the first capacitor and the fourth capacitor in the rear-stage charge pump circuit, and to charge the second capacitor, the third capacitor and the load capacitor in the rear-stage charge pump circuit;

[0018] If the first switch is turned on and the second switch is turned off, the rechargeable battery in the front-stage main circuit forms a loop with the second inductor, the first diode and the third diode in the rear-stage charge pump circuit are turned on, and the second diode and the output diode are turned off; and the current flowing through the second inductor in the front-stage main circuit is used to charge the first capacitor and the fourth capacitor in the rear-stage charge pump circuit, and to discharge the second capacitor and the third capacitor in the rear-stage charge pump circuit.

[0019] Optionally, the switch controller includes a feedforward module and a feedback module, the feedforward module is used to obtain the voltage of the rechargeable battery, and calculate the duty cycle of the drive waveform according to the voltage of the rechargeable battery and the output reference voltage; the feedback module is used to obtain the output voltage corresponding to the load resistor, calculate the voltage error according to the output voltage corresponding to the load resistor and the output reference voltage, and adjust the duty cycle of the drive waveform according to the voltage error.

[0020] An embodiment of the present application further provides a chip, which includes the above-mentioned DC / DC boost converter based on charge pump.

[0021] An embodiment of the present application further provides an energy storage device, which includes the DC / DC boost converter based on the charge pump as described above.

[0022] Compared with the prior art, the technical solution of the embodiment of the present application has the following advantages:

[0023] The charge pump-based DC / DC boost converter provided in the embodiment of the present application can achieve high-gain boost based on a smaller duty cycle by including a switch controller and a front-stage main circuit and a rear-stage charge pump circuit staggered in parallel, and can be applied to practical scenarios such as grid-connected household photovoltaic energy storage systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0025] Figure 1 This is a schematic diagram of the structure of a grid-connected household photovoltaic energy storage system;

[0026] Figure 2 Schematic diagram of the structure of a DC / DC boost converter based on a charge pump provided in an embodiment of the present application;

[0027] Figure 3 is an optional schematic diagram of driving waveforms of the first switch control signal S1' and the second switch control signal S2' provided in an embodiment of the present application;

[0028] Figure 4 is the circuit state of the DC / DC boost converter based on the charge pump corresponding to the situation a provided in the embodiment of the present application;

[0029] Figure 5 is the circuit state of the DC / DC boost converter based on the charge pump corresponding to the situation b provided in the embodiment of the present application;

[0030] Figure 6 is the circuit state of the DC / DC boost converter based on the charge pump corresponding to the situation c provided in the embodiment of the present application;

[0031] Figure 7 is a schematic diagram of an optional structure of a switch controller provided in an embodiment of the present application;

[0032] Figure 8 Schematic diagram of the waveform of the output voltage Vout of the DC / DC boost converter based on the charge pump provided in the embodiment of the present application. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0034] As described in the background technology, the grid-connected household photovoltaic energy storage system can save transmission and distribution costs, achieve lower costs, and improve power quality and energy efficiency. Figure 1The schematic diagram of the structure of a grid-connected household photovoltaic energy storage system is shown as an example. Figure 1 As shown, it includes a photovoltaic power generation module, a controller, a 20V battery, a DC / DC boost converter, a DC / AC converter and a power supply.

[0035] Among them, the photovoltaic power generation module is a collection of a certain number of photovoltaic component strings, in which multiple electrically connected solar cells are packaged to form a unit with rated voltage and current output under light, and is the smallest power generation unit that can be used independently in the photovoltaic power generation system. In the photovoltaic power generation system, after several photovoltaic components are connected in series, a circuit unit with a certain DC output voltage is formed.

[0036] The controller includes a maximum power point tracking module (MPPT Module) and a battery charger. The maximum power point tracking module can detect the power generation voltage of the photovoltaic power generation module in real time and track the maximum voltage and current value (VI), so that the system can charge the battery with maximum power output.

[0037] When the photovoltaic power generation module in the grid-connected household photovoltaic energy storage system charges the battery, the battery voltage (20V) needs to be boosted to a DC voltage of about 400V through a DC / DC boost converter (DC / DC boost converter). This DC voltage is called the high-voltage bus voltage, and finally converted into 220V AC power through an inverter to obtain a power supply that meets the 50Hz frequency and 220V voltage requirements of the power grid.

[0038] However, if the battery voltage is 20V, a conventional non-isolated boost converter is used to increase the voltage to 400V. The circuit switch tube of the Boost converter needs to have a higher duty cycle, that is, the voltage stress on the circuit switch tube of the Boost converter is directly output as the output voltage, which requires the Boost converter to have a higher device stress and significantly reduces its output efficiency (that is, the ratio of output power to input power).

[0039] As an optional implementation, multiple boost converters can be cascaded to achieve boosting, but this will increase the overall device size and device cost of the converter. As another optional implementation, flyback, half-bridge, full-bridge and other isolated topologies can be used for boosting, but the transformer design will be more complicated and the capacitor used will be larger.

[0040] In view of this, the embodiments of the present application provide an improved DC / DC boost converter solution, which can achieve high-gain boost based on a smaller duty cycle by including a switch controller and a front-stage main circuit and a rear-stage charge pump circuit that are staggered in parallel, and can be applied to actual scenarios such as grid-connected household photovoltaic energy storage systems.

[0041] Furthermore, under the control of the switch controller, compared with the conventional non-isolated Boost, the DC / DC boost converter based on the charge pump has a higher voltage gain and a smaller duty cycle required to achieve the boost; compared with the isolated converter, the transformer design is simpler, and the overall device size of the converter is smaller and the cost is lower.

[0042] Based on the above ideas, Figure 2 The structure diagram of the DC / DC boost converter based on the charge pump provided in the embodiment of the present application is shown as an example. Figure 2 As shown, the DC / DC boost converter based on the charge pump may include: a front-stage main circuit 1 and a rear-stage charge pump circuit 2 connected in parallel, and a switch controller ( Figure 2 The switch controller is not shown in the figure, and point AB can be understood as the connection point of the switch controller).

[0043] The front-stage main circuit 1 includes a rechargeable battery X, a first inductor L1, a second inductor L2, a first switch S1 and a second switch S2.

[0044] The rechargeable battery X is used to provide a battery voltage ViX, and the positive electrode of the rechargeable battery is connected to the first node T1 of the parallel connection branch of the positive electrodes of the first inductor L1 and the second inductor L2.

[0045] In a specific example, the first switch S1 and the second switch S2 may be field effect transistors. Thus, the negative electrode of the rechargeable battery X is connected to the second node T2 of the parallel connection branch of the gates of the first switch S1 and the second switch S2.

[0046] A cathode of the first inductor L1 is connected to a source of the first switch S1 .

[0047] The source of the first switch S1 is connected to the subsequent charge pump circuit 2 .

[0048] A cathode of the second inductor L2 is connected to a source of the second switch S2 .

[0049] The source of the second switch S2 is connected to the subsequent charge pump circuit 2 .

[0050] The post-stage charge pump circuit 2 includes a first capacitor C1, a second capacitor C2, a third capacitor C3, a fourth capacitor C4, a first diode D1, a second diode D2, a third diode D3, an output diode Dout, a load capacitor Cout and a load resistor Rout.

[0051] The first capacitor C1 and the third capacitor C3 are connected in parallel, and the second capacitor C2 and the fourth capacitor C4 are connected in parallel.

[0052] The first diode D1, the second diode D2, the third diode D3 and the output diode Dout are connected in series, and the anode of the first diode D1 is connected to the cathode of the first capacitor C1, the anode of the second diode D2 is connected to the cathode of the second capacitor C2, the anode of the third diode D3 is connected to the cathode of the third capacitor C3, and the anode of the output diode Dout is connected to the cathode of the fourth capacitor C4.

[0053] The negative electrode of the load capacitor Cout is connected to the positive electrode of the load resistor R, and the negative electrode of the load resistor R is connected to the positive electrode of the first diode D1.

[0054] The positive electrode of the load capacitor Cout is connected to the negative electrode of the output diode Dout, and the negative electrode of the load capacitor Cout is grounded GXD.

[0055] The switch controller is connected to the source of the first switch S1 and the source of the second switch S2 in the front-stage main circuit to provide a switch control signal to the first switch S1 and the second switch S2 to control the switch state of the first switch S1 and the second switch S2 to control the output voltage Vout in the rear-stage charge pump circuit.

[0056] As an optional implementation, the first switch S1 and the second switch S2 are field effect transistors. In a specific example, the source of the first switch S1 is connected to the subsequent charge pump circuit, which can be specifically connected to the third node T3 of the parallel connection branch of the second capacitor C2 and the fourth capacitor C4 in the subsequent charge pump circuit. The source of the second switch S2 is connected to the subsequent charge pump circuit, which can be specifically connected to the fourth node T4 of the parallel connection branch of the first capacitor C1 and the third capacitor C3 in the subsequent charge pump circuit.

[0057] In some embodiments, the switch control signal provided by the switch controller to the first switch S1 may be a first switch control signal, and the switch control signal provided to the second switch S2 may be a second switch control signal.

[0058] The first switch control signal and the second switch control signal may have the same time period and duty cycle, and the driving waveforms of the first switch control signal and the second switch control signal are associated with each other.

[0059] It should be noted that the correlation relationship between the driving waveforms of the first switch control signal and the second switch control signal may be a time delay relationship of the waveforms. As an optional implementation, the correlation relationship between the driving waveforms of the first switch control signal and the second switch control signal may be: the phase difference corresponding to the waveform phase of the first switch control signal and the waveform phase of the second switch control signal is 180°. As another optional implementation, the correlation relationship between the driving waveforms of the first switch control signal and the second switch control signal may be: the driving waveform of the first switch control signal and the driving waveform of the second switch control signal differ in time by Ts / 2.

[0060] Figure 3 An optional schematic diagram of the driving waveforms of the first switch control signal S1' and the second switch control signal S2' is shown as an example. Figure 3 As shown, the driving waveforms of S1' and S2' have the same period Ts and duty cycle d1 = d2 = d, and the driving waveforms of S1' and S2' differ in phase by 180°. Corresponding to S1' and S2', the first switch and the second switch can correspond to three working states, namely mode1, mode2 and mode3. Among them, when the driving waveform is at a high level, it indicates that the switch is turned on; when the driving waveform is at a low level, it indicates that the switch is turned off.

[0061] In some embodiments, see Figure 3 The driving waveform diagram shown corresponds to the first switch control signal S1' and the second switch control signal S2'. The three working states corresponding to the first switch and the second switch are: a. Both the first switch and the second switch are turned on; b. The first switch is turned off and the second switch is turned on; c. The first switch is turned on and the second switch is turned off.

[0062] If the first switch and the second switch are turned on, that is, case a, Figure 4 The circuit state of the DC / DC boost converter based on the charge pump corresponding to case a is shown as an example. Figure 4 As shown, the rechargeable battery X in the front-stage main circuit can form a loop with the first inductor L1 and the second inductor L2 respectively, and the output voltage Vout of the load resistor R in the back-stage charge pump circuit corresponds to the load capacitor Cout. Moreover, the four diodes (i.e., the first diode D1, the second diode D2, the third diode D3 and the output diode Dout) are not conducting, and the capacitors C1, C2, C3 and C4 maintain their original states.

[0063] If the first switch is off and the second switch is on, that is, case b, Figure 5 The circuit state of the DC / DC boost converter based on the charge pump corresponding to case b is shown as an example. Figure 5 As shown, the rechargeable battery X in the front-stage main circuit forms a loop with the first inductor L1, the first diode D1 and the third diode D3 in the rear-stage charge pump circuit are turned off, the second diode D2 and the output diode Dout are turned on, and see Figure 5 As shown by the arrow indicating the direction of current flow in the front-stage main circuit, the current flowing through the first inductor L1 in the front-stage main circuit is used to discharge the first capacitor C1 and the fourth capacitor C4 in the rear-stage charge pump circuit, charge the second capacitor C2, the third capacitor C3 and the load capacitor Cout in the rear-stage charge pump circuit, and provide energy to the output voltage Vout corresponding to the load resistor R.

[0064] correspond Figure 5 As shown, the equation for the voltage corresponding to the inductor L1 is:

[0065]

[0066] Among them, V AN is the voltage between point A and point N, V C1 、V C2 、V C3 、V C4 is the voltage across capacitors C1, C2, C3, and C4, ViN is the voltage of the rechargeable battery, Vout is the output voltage, and d is the duty cycle of the drive waveform of switches S1 and S2.

[0067] If the first switch is turned on and the second switch is turned off, that is, case c, Figure 6 The circuit state of the DC / DC boost converter based on the charge pump corresponding to case c is shown as an example. Figure 6 As shown, the rechargeable battery X in the front-stage main circuit forms a loop with the second inductor L2, the first diode D1 and the third diode D3 in the rear-stage charge pump circuit are turned on, the second diode D2 and the output diode Dout are turned off, and see Figure 6 As shown by the arrow indicating the direction of current flow in the front-stage main circuit, the current flowing through the second inductor L2 in the front-stage main circuit is used to charge the first capacitor C1 and the fourth capacitor C4 in the rear-stage charge pump circuit, and discharge the second capacitor C2 and the third capacitor C3 in the rear-stage charge pump circuit, and the output voltage Vout corresponding to the load resistor R is provided with energy by the output capacitor Cout.

[0068] correspond Figure 6 As shown, the equation for the voltage corresponding to the inductor L2 is:

[0069]

[0070] Among them, V BN is the voltage between point B and point N.

[0071] Corresponding to the current flow conditions of case b and case c, if the capacitance C1 = C2 = C3 = C4 is set in the front-stage main circuit, according to equations (1) and (2), we can obtain:

[0072]

[0073] Substituting formula (3) and formula (4) into formula (1), we can get the output gain function:

[0074]

[0075] The gain ratio of the output voltage Vout to the voltage Vin of the rechargeable battery is Compared with the gain of a traditional boost converter, the voltage gain of the embodiment of the present application is increased by 4 times.

[0076] In some embodiments, Figure 7 The optional structural diagram of the switch controller is shown as an example. Figure 7 As shown, the switch controller includes a feedforward module M1 and a feedback module M2.

[0077] The feedforward module M1 is used to obtain the voltage of the rechargeable battery X, and calculate the duty cycle of the driving waveform according to the voltage of the rechargeable battery and the output reference voltage. The feedback module M2 is used to obtain the output voltage corresponding to the load resistor R, calculate the voltage error according to the output voltage corresponding to the load resistor and the output reference voltage, and adjust the duty cycle of the driving waveform according to the voltage error.

[0078] In a specific example, the feedforward module obtains the voltage Vin of the rechargeable battery X and the output reference voltage Vref, and substitutes Vin and Vref into the following formula to calculate the duty cycle d of the driving waveform:

[0079]

[0080] The feedback module obtains the output voltage Vout and calculates the voltage error between Vout and Vref. Moreover, according to the obtained voltage error, the duty cycle of the driving waveform can be fine-tuned through PI control, thereby reducing the output error, improving the stability of the system, and ensuring that the DC / DC boost converter based on the charge pump achieves high gain boost based on a small duty cycle.

[0081] It can be seen that under the control of the switch controller, compared with the conventional non-isolated Boost boost, the DC / DC boost converter based on the charge pump has a higher voltage gain and a smaller duty cycle required to achieve the boost; compared with the isolated converter, the transformer design is simpler, the overall device size of the converter is smaller, and the cost is lower.

[0082] It should be noted that, in order to realize the control of the driving waveform by the switch controller, the switch controller of the embodiment of the present application can be a hardware device obtained based on the software system implementation, or it can be a hardware device obtained based on the circuit design, and the embodiment of the present application does not limit this.

[0083] In order to verify the high gain boost effect of the DC / DC boost converter based on the charge pump of the present application, simulation verification is performed using MATLAB / simulink. The circuit parameters of the DC / DC boost converter based on the charge pump are shown in Table 1:

[0084] parameter value Battery voltage (Vin) 20V Output voltage reference voltage (Vref) 400V Inductors L1, L2 100uH Capacitors C1, C2, C3, C4 60uF Output capacitor Cout 220uF Output resistance R 800Ω PWM waveform frequency 100KHz Simulation time 0.5s

[0085] Table 1

[0086] Corresponding to the parameter settings in Table 1, Figure 8 The waveform diagram of the output voltage Vout of the DC / DC boost converter based on the charge pump in the embodiment of the present application is shown as an example. Figure 8 As shown, the final output voltage Vout can be stabilized at 400V, and the DC / DC boost converter based on the charge pump in the embodiment of the present application has a better voltage stabilization effect and has continuous working response capability.

[0087] It can be seen that the DC / DC boost converter based on the charge pump in the embodiment of the present application can achieve high-gain boost based on a smaller duty cycle by including a switch controller and a front-stage main circuit and a rear-stage charge pump circuit that are staggered in parallel, and can be applied to actual scenarios such as grid-connected household photovoltaic energy storage systems.

[0088] Furthermore, under the control of the switch controller, compared with the conventional non-isolated Boost, the DC / DC boost converter based on the charge pump has a higher voltage gain and a smaller duty cycle required to achieve the boost; compared with the isolated converter, the transformer design is simpler, and the overall device size of the converter is smaller and the cost is lower.

[0089] An embodiment of the present application also provides a chip, which includes a DC / DC boost converter based on a charge pump as provided in the embodiment of the present application.

[0090] An embodiment of the present application also provides an energy storage device, which may be, for example, a battery, a lithium battery cell, a mobile power supply, a photovoltaic energy storage device, etc. The energy storage device may include a DC / DC boost converter based on a charge pump as provided in an embodiment of the present application.

[0091] The above describes multiple implementation schemes provided by the embodiments of the present application. The various optional methods introduced in each implementation scheme can be combined and cross-referenced with each other without conflict, thereby extending a variety of possible implementation schemes, which can all be considered as implementation schemes disclosed and open in the embodiments of the present application.

[0092] Although the embodiments of the present application are disclosed above, the present application is not limited thereto. Any person skilled in the art may make various changes and modifications without departing from the spirit and scope of the present application. Therefore, the scope of protection of the present application shall be subject to the scope defined by the claims.

Claims

1. A DC / DC boost converter based on a charge pump, characterized in that: include: A switch controller and a front-stage main circuit and a rear-stage charge pump circuit connected in parallel; The front-stage main circuit includes a rechargeable battery, a first inductor, a second inductor, a first switch and a second switch; wherein the rechargeable battery is used to provide a battery voltage, the positive electrode of the rechargeable battery is connected to the first node of the positive electrode of the first inductor and the second inductor connected in parallel on the branch; the negative electrode of the rechargeable battery is connected to the second node of the gate electrode of the first switch and the second switch connected in parallel on the branch; the negative electrode of the first inductor is connected to the source electrode of the first switch; the source electrode of the first switch is connected to the rear-stage charge pump circuit; the negative electrode of the second inductor is connected to the source electrode of the second switch; the source electrode of the second switch is connected to the rear-stage charge pump circuit; The post-stage charge pump circuit includes a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, a first diode, a second diode, a third diode, an output diode, a load capacitor and a load resistor; wherein the first capacitor and the third capacitor are connected in parallel, and the second capacitor and the fourth capacitor are connected in parallel; the first diode, the second diode, the third diode and the output diode are connected in series; and the positive electrode of the first diode is connected to the negative electrode of the first capacitor, the positive electrode of the second diode is connected to the negative electrode of the second capacitor, the positive electrode of the third diode is connected to the negative electrode of the third capacitor, and the positive electrode of the output diode is connected to the negative electrode of the fourth capacitor; the negative electrode of the load capacitor is connected to the positive electrode of the load resistor, and the negative electrode of the load resistor is connected to the positive electrode of the first diode; the positive electrode of the load capacitor is connected to the negative electrode of the output diode; and the negative electrode of the load capacitor is grounded; The switch controller is connected to the source of the first switch and the source of the second switch in the front-stage main circuit to provide a switch control signal to the first switch and the second switch to control the switch state of the first switch and the second switch to control the output voltage in the rear-stage charge pump circuit.

2. The DC / DC boost converter based on charge pump according to claim 1, characterized in that: The source of the first switch is connected to the subsequent charge pump circuit specifically: the source of the first switch is connected to the third node of the parallel connection branch of the second capacitor and the fourth capacitor in the subsequent charge pump circuit; The source of the second switch is connected to the subsequent charge pump circuit specifically: the source of the second switch is connected to the fourth node on the parallel connection branch of the first capacitor and the third capacitor in the subsequent charge pump circuit.

3. The DC / DC boost converter based on charge pump according to claim 2, characterized in that: The switch control signal provided by the switch controller to the first switch is a first switch control signal, and the switch control signal provided by the switch controller to the second switch is a second switch control signal; The first switch control signal and the second switch control signal have the same time period and duty cycle, and the driving waveforms of the first switch control signal and the second switch control signal are associated with each other.

4. The DC / DC boost converter based on charge pump according to claim 3, characterized in that: The correlation relationship between the driving waveforms of the first switch control signal and the second switch control signal is: the phase difference corresponding to the waveform phase of the first switch control signal and the waveform phase of the second switch control signal is 180°.

5. The DC / DC boost converter based on charge pump according to claim 4, characterized in that: Corresponding to the first switch control signal and the second switch control signal, If the first switch and the second switch are turned on, the rechargeable battery in the front-stage main circuit forms a loop with the first inductor and the second inductor respectively, and the output voltage of the load resistor in the rear-stage charge pump circuit corresponds to the load capacitance; If the first switch is turned off and the second switch is turned on, the rechargeable battery in the front-stage main circuit forms a loop with the first inductor, the first diode and the third diode in the rear-stage charge pump circuit are turned off, and the second diode and the output diode are turned on; and the current flowing through the first inductor in the front-stage main circuit is used to discharge the first capacitor and the fourth capacitor in the rear-stage charge pump circuit, and to charge the second capacitor, the third capacitor and the load capacitor in the rear-stage charge pump circuit; If the first switch is turned on and the second switch is turned off, the rechargeable battery in the front-stage main circuit forms a loop with the second inductor, the first diode and the third diode in the rear-stage charge pump circuit are turned on, and the second diode and the output diode are turned off; and the current flowing through the second inductor in the front-stage main circuit is used to charge the first capacitor and the fourth capacitor in the rear-stage charge pump circuit, and to discharge the second capacitor and the third capacitor in the rear-stage charge pump circuit.

6. The DC / DC boost converter based on charge pump according to claim 1, characterized in that: The switch controller includes a feedforward module and a feedback module, wherein the feedforward module is used to obtain the voltage of the rechargeable battery and calculate the duty cycle of the driving waveform according to the voltage of the rechargeable battery and the output reference voltage; The feedback module is used to obtain the output voltage corresponding to the load resistor, calculate the voltage error according to the output voltage corresponding to the load resistor and the output reference voltage, and adjust the duty cycle of the driving waveform according to the voltage error.

7. A chip, characterized in that: A DC / DC boost converter based on a charge pump comprising any one of claims 1 to 6.

8. An energy storage device, characterized in that: It comprises a DC / DC boost converter based on a charge pump as claimed in any one of claims 1 to 6.

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