Insulation resistance detection circuit, power supply circuit and energy storage equipment

The invention provides an insulation resistance detection circuit, a power supply circuit and energy storage equipment, the insulation resistance detection circuit comprises a first switch unit, a second switch unit, a third switch unit, a fourth switch unit, a first resistor unit, a second resistor unit and a control unit, and the control unit can control each switch unit. The negative direct current bus voltage, the positive direct current bus voltage and the positive electrode input end voltage of the voltage conversion circuit in different working states are obtained; according to the negative direct-current bus voltage and the positive direct-current bus voltage in different working states, the voltage of the positive input end of the voltage conversion circuit, the resistance value of the first resistor unit and the resistance value of the second resistor unit; and calculating the insulation resistance between the positive input end of the voltage conversion circuit and the common end and the insulation