Piezoelectric energy collection system based on inductor

Abstract

The invention discloses a piezoelectric energy collection system based on an inductor and relates to the technical field of the power management chip. The system comprises a piezoelectric element, a synchronous alternating switch circuit, a zero-cross detection circuit, a signal generation circuit, a rectification circuit and a load. According to the novel piezoelectric energy acquisition circuit based on the inductor, two sets of synchronous switches are arranged in a synchronous alternating switch circuit, the used synchronous switches are alternately switched in each half period, the directions of currents flowing through the inductor and a sampling resistor are always consistent, and the circuit structure is greatly simplified; and the signal generation circuit processes the information of the sampling resistor in the synchronous alternating switch circuit at a 1 / 2 resonance period, accurately generates a control signal of a synchronous switch, improves the voltage overturning efficiency, reduces the loss, and improves the output power of a circuit system.

Description

technical field [0001] The invention relates to the technical field of power management chips, in particular to an inductance-based piezoelectric energy harvesting system. Background technique [0002] With the development of science and technology, piezoelectric energy harvesting technology has been widely used due to its advantages of high energy density, easy implementation and small size. In order to improve the efficiency of piezoelectric energy harvesting, scholars at home and abroad have proposed synchronous switch technology. Technology has high requirements on the accuracy of synchronous control signals. If the signal delay is large, it will cause large energy loss. [0003] The existing piezoelectric energy harvesting circuit based on synchronous switch technology has a complex structure, is difficult to implement, and the control of the synchronous switch is not accurate enough. The basic P-SSHI circuit has very high requirements for the accuracy of the synchronou...

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Problems solved by technology

[0002] With the development of science and technology, piezoelectric energy harvesting technology has been widely used due to its advantages of high energy density, easy implementation and small size. In order to improve the efficiency of piezoelectric energy harvesting, scholars at home and abroad have proposed synchronous switch technology. Technology has high requirements on the accuracy of synchronous control signals. If the signal delay is large, it will cause large energy loss

[0003] The existing piezoelectric energy harvesting circuit based on synchronous switch technology has a complex structure, is difficult to implement, and the control of the synchronous switch is not accurate enough. The basic P-SSHI circuit has very high requirements for the accuracy of the synchronous switch. If it cannot be within 1 / 2 The resonant cycle stops resonating and enters the next stage, which will cause the following effects:

[0004] 1) When the synchronous switch is turned off, the energy of the inductor is not fully transmitted to the capacitor or the capacitor starts to transfer energy to the inductor again, and there is still residual energy in the inductor. With the disconnection of the resonant circuit, the electric energy is converted by electric sparks, etc. For other forms of energy loss, the output power of the circuit system is reduced;

[0005] 2), without considering the loss, the voltage across the capacitor cannot reach -(V L +2V D ), the voltage inversion efficiency decreases, V PT decreases, the output voltage of the circuit system decreases

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